Systems, devices, and methods for accessing an extravascular space and removal of fluids therefrom

Abstract

Systems, devices, and methods for accessing an intracranial extravascular space may include advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. A perforating element may be advanced through at least a portion of a lumen of the catheter. A wall of the intracranial vessel may be obliquely perforated using the perforating element while the perforating element extends substantially parallel to the intracranial vessel to form an opening into the intracranial extravascular space. The distal end of the perforating element may be advanced within the intracranial extravascular space. The catheter may be advanced over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space. A surgical procedure may be performed after the distal end of the catheter is disposed in the intracranial extravascular space.

Description

SYSTEMS, DEVICES, AND METHODS FOR ACCESSING AN EXTRA VASCULAR SPACE AND REMOVAL OF FLUIDS THEREFROMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 645,039, filed May 9, 2024, U.S. Provisional Application No. 63 / 645,053, filed May 9, 2024, and U.S. Provisional Application No. 63 / 753,808, filed February 4, 2025, the content of each of which are hereby incorporated by reference in their entirety.TECHNICAL FIELD

[0002] Devices, systems, and methods herein relate to minimally invasive procedures for accessing an extravascular space in a subject, including, for example, accessing a subdural space and treating a subdural hematoma.BACKGROUND

[0003] A subdural hematoma (SDH) is a collection of blood outside the brain generally resulting from head trauma and commonly associated with blood thinners. If not surgically drained, an SDH may cause an increase in the pressure inside the skull, damage delicate brain tissue, and become life-threatening. Initially, an acute SDH (aSDH) is generally formed by stiff clots, but may progressively liquefy in subsequent days into a viscous subacute SDH (saSDH), which tends to perpetuate and expand into a chronic SDH (eSDH). A chronic subdural hematoma (eSDH) is a collection of blood on the brain's surface that generally begins forming weeks after head trauma and expands, with the potential to cause brain compression, neurologic deficits, and death. eSDH is expected to be the most common neurosurgical diagnosis in the United States by the year 2030 and has an in-hospital mortality rate of 16.7%, a 1-year mortality rate of 32% with only 21.1% of patients admitted returning home, and is associated with a marked reduction in patient life expectancy. eSDH is becoming a public health issue in aging populations as it is associated with brain atrophy in elderly patients and anti-coagulation with the use of blood thinners. Furthermore, acute-on- chronic SDH (acSDH) occurs for more than 10% of patients with eSDH and may be formed by encapsulated liquefied hematoma mixed with solid subdural clots.

[0004] The current standard of treatment for symptomatic SDH is surgical evacuation. For example, two burr holes are formed to drain the relatively thin eSDH, and craniotomies (e.g., large bone ‘windows’) are used to drain the viscous fluids and / or clots of an aSDH and acSDH. Surgical evacuation may be initially effective, but have a failure rate of up to about 37%. Even when an initial conventional treatment fails and patients undergo a second surgical treatment, further recurrences are common; recurrence for eSDH can be up to about 46%. Furthermore, open surgical intervention may pose additional risks to a patient including temporary discontinuation of anti coagulation and antiplatelet medications (e.g., thereby increasing the risk of ischemic complications) and the use of general anesthesia may contribute to morbidity and mortality rates as high as about 25% and about 11%, respectively.

[0005] Surgical evacuation is commonly combined with the introduction of drains in the subdural space, which generally remain in place for up to about three days. While drains may reduce the recurrence rate and the 6-month mortality rate by about 50%, they may also result in other complications such as brain injury, hemorrhage from neomembranes, and infection.

[0006] Endovascular middle meningeal artery (MMA) embolization is an endovascular procedure used to reduce postoperative recurrence of SDH that includes the injection of embolic agents in the MMA whereby the hematoma is slowly reabsorbed, thus reducing the mass effect on the brain over a period of weeks to months. MMA embolization may be used to treat eSDH and reduce recurrence in high-risk patients with aSDH, saSDH, and acSDH (i.e., coagulopathy or requiring blood thinners).

[0007] Surgical evacuation for rapid brain decompression has been used with endovascular MMA as a preoperative or postoperative adjunct to treat SDH. However, such a combination carries their aforementioned risks and further requires two separate procedures that may increase hospitalization, recovery time, and healthcare costs. Accordingly, it may be desirable to provide a single endovascular procedure to access a subdural space to facilitate evacuation of an SDH and embolization of an artery.SUMMARY

[0008] Described here are systems, devices, and methods useful for minimally invasive surgical procedures. These systems, devices, and methods may, for example, access an extravascular space (e.g., subdural space, intradural cavity) and treat a subdural hematoma ofa subject. For example, drainage of one or more of intracranial extravascular fluid, thrombus, and particulate matter (e.g., subdural hematoma) and embolization of the middle meningeal artery in a single endovascular intervention (e.g., approach) are described herein.

[0009] In some embodiments, a method of accessing an intracranial extravascular space of a patient may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. A wall of the intracranial vessel may be obliquely perforated using the perforating element while the perforating element extends substantially parallel to the intracranial vessel to form an opening into the intracranial extravascular space.

[0010] The distal end of the perforating element may be advanced within the intracranial extravascular space. The catheter may be advanced over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space. An extravascular procedure may be performed via the catheter after the distal end of the catheter is disposed in the intracranial extravascular space. After performing the endovascular procedure, the opening may be closed.

[0011] In some embodiments, an epidural channel may be formed using the perforating element. Closing the opening may include placing an occlusion device in the intracranial extravascular space and occluding the epidural channel and the intracranial vessel using the occlusion device. In some embodiments, closing the opening includes: implanting an occlusion device, delivering an embolization agent, or applying energy to a portion of the intracranial vessel.

[0012] In some embodiments, performing the surgical procedure includes at least one of: draining fluid or matter from the intracranial extravascular space, performing a biopsy of brain matter, or delivering a therapy or a device. In some embodiments, advancing the catheter over the perforating element may include advancing the catheter over the perforating element by more than 0.5 cm within the intracranial extravascular space.

[0013] In some embodiments, obliquely perforating the wall of the intracranial vessel may include applying energy via the perforating element to the wall of the intracranial vessel. Insome embodiments, the dura may be obliquely perforated to form a passageway into the subdural space. The extravascular procedure may be performed in the subdural space. In some embodiments, the intracranial vessel may be the middle meningeal artery.

[0014] Also described are methods. In some embodiments, a method of forming a passageway through a wall of an intracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within the intracranial vessel. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. The perforating element may be directionally guided towards a wall of the intracranial vessel and the dura using anatomical features proximate to the intracranial vessel. The wall of the intracranial vessel and the dura may be obliquely perforated using the perforating element while the perforating element is directionally guided toward the wall of the intracranial vessel and the dura to form a passageway into the intracranial extravascular space.

[0015] In some embodiments, obliquely perforating the wall of the intracranial vessel and the dura may include applying energy using the perforating element to the wall of the intracranial vessel and the dura to perforate therethrough.

[0016] In some embodiments, rotating or applying torque to the perforating element may enable circumferential application of energy to vaporize the wall of the intracranial vessel and the dura to form the passageway into the transcranial extravascular space.

[0017] In some embodiments, the passageway may be formed at the lower skull. In some embodiments, the anatomical feature may include at least one of: a bony ridge of an inner surface of the skull, a bony overhang of the skull, or a bony channel of the skull.

[0018] In some embodiments, the perforating element may have a linear tip, and directionally guiding the perforating element toward the wall of the intracranial vessel and the dura includes using a bony feature of the skull adjacent to the intracranial vessel to direct the linear tip of the perforating element toward the wall of the intracranial vessel and the dura.

[0019] In some embodiments, the perforating element may have a curved tip configured to curve toward the wall of the intracranial vessel and the dura. In some embodiments, the intracranial vessel may be the middle meningeal artery. In some embodiments, the catheter may be advanced over the perforating element and into the intracranial extravascular space. Fluid or matter may be drained from the intracranial extravascular space via the catheter.

[0020] In some embodiments, the catheter may be advanced over the perforating element and into the intracranial extravascular space. A therapy or a device may be delivered to the intracranial extravascular space via the catheter.

[0021] Also described herein are methods. In some embodiments, a method of forming a passageway through a wall of an intracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. A wall of the intracranial vessel and the dura may be perforated using the perforating element to form a passageway into the intracranial extravascular space. A dilation device may be advanced over the perforating element through the passageway. An expandable member of the dilation device may be transitioned into an expanded configuration to enlarge the passageway.

[0022] In some embodiments, the expandable member may include a balloon, a stent, or a basket. In some embodiments, the expandable member in the expanded configuration includes a tapered structure that increases in diameter proximally. In some embodiments, transitioning the expandable member into the expanded configuration may cause compression against the dura and nearby bony structure to secure the dilation device in position for enlarging the passageway.

[0023] In some embodiments, after enlarging the passageway, the expandable member may transition back to an unexpanded configuration. The catheter may be advanced over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space. A surgical procedure may be performed via the catheter after the distal end of the catheter is disposed in the intracranial extravascular space. In some embodiments, performing the surgical procedure includes at least one of: draining fluid or matter from theintracranial extravascular space, performing a biopsy of brain matter, or delivering a therapy or a device.

[0024] Also described herein are apparatuses. In some embodiments, an apparatus may comprise an elongate body defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel. A plurality of apertures may be disposed on the distal end of the elongate body. The plurality of apertures may be configured to drain fluid or matter from an intracranial extravascular space. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be advanced into the intracranial vessel to perforate a wall of the intracranial vessel and to form a passageway into the intracranial extravascular space. The elongate body may be further configured to be advanced over the perforating device into the intracranial extravascular space such that the plurality of apertures can drain fluid or matter from the intracranial extravascular space.

[0025] In some embodiments, the plurality of apertures may be disposed on a distal length of the elongate body having a length of between about 1 cm and about 10 cm. In some embodiments, the plurality of apertures may include at least one of holes, slits, or slots. In some embodiments, the plurality of apertures may have one or more of a circle, an oval, an ellipse, a square, a star, a diamond, a rectangle, or an elongate shape. In some embodiments, the distal end of the elongate body may be formed from a braid that defines the plurality of apertures. In some embodiments, the distal end of the elongate body may be configured to transition to a treatment configuration having a non-linear, shaped section.

[0026] In some embodiments, the non-linear shaped section may include one or more markers configured to indicate a shape or a location of the non-linear shaped section. In some embodiments, one or more expandable elements or protrusions may be configured to reduce an occlusion of one or more of the plurality of apertures. In some embodiments, a pull wire or a magnet may be configured to enable the elongate body to be steered within a vasculature to the location in the intracranial vessel.

[0027] Also described herein are apparatuses. In some embodiments, an apparatus may comprise an elongate body defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel, the lumen including a distal curve. Anopening may be disposed on the distal end of the elongate body, the opening being in communication with the lumen. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be guided via the distal curve and out through the opening toward a wall of the intracranial vessel to perforate the wall and form a passageway into the intracranial extravascular space.

[0028] In some embodiments, a pull wire or a magnet may be configured to enable the elongate body to be steered within a vasculature to the location in the intracranial vessel. In some embodiments, the distal curve may be configured to direct the perforating device out through the opening at an angle of between about 5 degrees and about 90 degrees from a plane perpendicular to a longitudinal axis of the elongate body. In some embodiments, one or more markers may be configured to indicate a position of the elongate body within the intracranial vessel.

[0029] Also described herein are apparatuses. In some embodiments, an apparatus may comprise an elongate body defining a lumen, the elongate body including a proximal end having a first coupling portion and a distal end configured to be disposed in an intracranial vessel. A perforating device may include a second coupling portion. The perforating device may be configured to be advanced through the lumen of the elongate body until the second coupling portion of the perforating device engages with the first coupling portion of the elongate body. The perforating device, when advanced such that the first and second coupling portions are engaged, may be further configured to perforate through a wall of the intracranial vessel to form a passageway into the intracranial extravascular space. In some embodiments, a wire may be coupled to the proximal end of the elongate body. The wire may be configured to distally advance the elongate body.

[0030] In some embodiments, the perforating device may include a paddle structure configured to apply energy to the wall of the intracranial vessel to form the passageway into the intracranial extravascular space. The paddle structure may be configured to act as a heat sink during application of the energy. In some embodiments, the perforating device may include an insulating material disposed along a length of the perforating device proximal of the paddle structure. The paddle structure may have an outer diameter that provides a smooth transition from the insulating material to the paddle structure.

[0031] In some embodiments, the perforating device may include a needle configured to mechanically perforate the wall of the intracranial vessel to form the passageway into the intracranial extravascular space. In some embodiments, the needle may include one or more of an angled opening, a circumferential spiral cut opening, a spiral opening, or external threading.

[0032] In some embodiments, at least one of the elongate body or the perforating device may include one or more fluoroscopic markers configured to be imaged by a visualization device to indicate a location or a configuration of the at least one of the elongate body or the perforating device.

[0033] In some embodiments, an expandable element may be configured to expand to anchor the elongate body within the intracranial vessel.

[0034] In some embodiments, an energy delivery device may be configured to be advanced through the lumen and into the intracranial vessel. The energy delivery device may be configured to deliver bipolar energy to the intracranial vessel to coagulate the intracranial vessel.

[0035] In some embodiments, the perforating device may be further configured to apply energy to the intracranial vessel to coagulate the intracranial vessel.

[0036] In some embodiments, a hemostatic device may be configured to occlude the intracranial vessel. In some embodiments, the hemostatic device may include a carrier structure and a hydrogel disposed around the carrier structure, the hydrogel configured to expand to occlude the intracranial vessel.

[0037] In some embodiments, the hemostatic device may be configured to transition to a preformed shape that facilitates anchoring to the wall of the intracranial vessel or nearby anatomy.

[0038] In some embodiments, the apparatus may comprise a pressure sensor configured to capture pressure measurements at a distal end of the perforating device to monitor a location or state of the perforating device.

[0039] Also described herein are apparatuses. In some embodiments, an apparatus may comprise an elongate body (e.g., catheter) defining a lumen, the elongate body including a distal end configured to be advanced through an intracranial vessel and into an intracranial extravascular space over a shaft. The elongate body may further include a proximal end configured to be coupled to a source of therapy such that the therapy can be delivered to the intracranial extravascular space via the catheter. An anchor may be coupled to the elongate body and configured to expand to releasably anchor the elongate body to tissue.

[0040] In some embodiments, the intracranial vessel may be the middle meningeal artery. In some embodiments, the shaft may comprise a perforating device that is configured to perforate a wall of the intracranial vessel to form a passageway into the intracranial extravascular space, the elongate body being configured to be advanced over the shaft and through the passageway into the intracranial extravascular space. In some embodiments, a sensor may be configured to monitor a state of the elongate body or a condition within the intracranial extravascular space.BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG. 1 is a schematic coronal cross-sectional view of a subdural hematoma of a subject, according to embodiments.

[0042] FIG. 2 is a schematic perspective view of a subject undergoing surgical evacuation, according to embodiments.

[0043] FIG. 3 A is a schematic representation of a side view of a head of a subject, according to embodiments. FIGS. 3B-3D are coronal cross-sectional views of a head of a subject, according to embodiments.

[0044] FIG. 4 is a schematic representation of a lateral view of a head of a subject, according to embodiments.

[0045] FIG. 5 is a schematic block diagram of a system, according to embodiments.

[0046] FIG. 6A is a schematic side view of a catheter, according to embodiments. FIG. 6B is a schematic cross-sectional diagram of a catheter, according to embodiments.

[0047] FIGS. 7A and 7G are schematic side views of a catheter, according to embodiments. FIGS. 7B and 7C are schematic cross-sectional diagrams of a catheter, according to embodiments. FIG. 7D is a cross-sectional front view of a catheter including apertures, according to embodiments. FIGS. 7E and 7F are schematic side views of catheters including apertures, according to embodiments.

[0048] FIG. 8 is a schematic side view of a catheter, according to embodiments.

[0049] FIG. 9 are schematic side and cross-sectional side views of a catheter, according to embodiments.

[0050] FIG. 10A are schematic side views of a catheter, according to embodiments. FIG. 10B is a schematic side view of a catheter, according to embodiments. FIG. 10C are schematic side and front views of a catheter, according to embodiments. FIG. 10D are schematic lateral views of a catheter in a head of a subject, according to embodiments.

[0051] FIG. 11 A is a schematic side view of a catheter, according to embodiments. FIG. 1 IB is a schematic side views of a catheter in a first configuration, according to embodiments. FIG. 11C is a schematic side view of a catheter in a second configuration, according to embodiments.

[0052] FIGS. 12A-12C are schematic side views of catheters, according to embodiments.

[0053] FIG. 13 A is a schematic side view of a catheter in a first configuration, according to embodiments. FIG. 13B is a schematic side view of a catheter in a second configuration, according to embodiments.

[0054] FIG. 14A is a schematic cross-sectional side view of a catheter assembly, according to embodiments. FIG. 14B is a schematic cross-sectional side view of the catheter assembly depicted in FIG. 14A in a head of a subject, according to embodiments.

[0055] FIG. 15A is a schematic cross-sectional side view of a catheter, according to embodiments. FIG. 15B are schematic detailed cross-sectional side and perspective views of a catheter, according to embodiments. FIGS. 15C, 15D, and 15F are schematic detailed cross- sectional side view of catheters, according to embodiments. FIG. 15E is a schematic detailed side view of a catheter, according to embodiments.

[0056] FIG. 16A is schematic cross-sectional side view of a catheter, according to embodiments. FIG. 16B is a schematic cross-sectional front view of the catheter depicted in FIG. 16 A, according to embodiments.

[0057] FIG. 17A is an X-ray image of arterial blood flow in a head of a subject, according to embodiments. FIG. 17B is a schematic cross-sectional view of a catheter assembly in a head of a subject, according to embodiments.

[0058] FIGS. 18A-18D are schematic cross-sectional side views of a catheter assembly, according to embodiments.

[0059] FIGS. 19A-19D are schematic detailed cross-sectional side views of a catheter assembly, according to embodiments.

[0060] FIGS. 20A and 20B are schematic cross-sectional side views of a catheter assembly, according to embodiments.

[0061] FIG. 21 is an X-ray image of arterial blood flow in a head of a subject and exemplary perforating devices, according to embodiments.

[0062] FIGS. 22A-22C are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments.

[0063] FIGS. 23 A-23F are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments.

[0064] FIGS. 24A - 24C are schematic side views of respective perforating elements of perforating devices, according to embodiments. FIG. 24D is a schematic detailed cross- sectional side view and front view of the perforating element depicted in FIG. 24C, according to embodiments.

[0065] FIG. 25A is a schematic cross-sectional side view of a perforating device, according to embodiments. FIG. 25B is a schematic cross-sectional side view of a catheter, according to embodiments. FIG. 25C is a schematic cross-sectional side view of a catheter assembly, according to embodiments.

[0066] FIGS. 26A, 26B, and 26E are schematic cross-sectional side views of a catheter assembly, according to embodiments. FIG. 26C is a schematic cross-sectional front view of a catheter assembly, according to embodiments. FIG. 26D is a schematic cross-sectional perspective view of a catheter assembly, according to embodiments. FIGS. 26F and 26G are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments.

[0067] FIGS. 27A and 27B are schematic cross-sectional side views of a catheter assembly, according to embodiments.

[0068] FIGS. 28A and 28B are schematic cross-sectional side views of a perforating device, according to embodiments.

[0069] FIG. 29 is a schematic diagram of a system, according to embodiments.

[0070] FIG. 30A is a schematic diagram of a perforating device, according to embodiments. FIG. 30B is a detailed schematic diagram of the perforating device depicted in FIG. 30A, according to embodiments.

[0071] FIG. 30C is a schematic diagram of a perforating device, according to embodiments. FIG. 30D is a detailed schematic diagram of the perforating device depicted in FIG. 30A, according to embodiments. FIG. 30E is a detailed schematic diagram of the perforating devices depicted in FIGS. 30A and 30C, according to embodiments.

[0072] FIG. 31 is a schematic diagram of a perforating device, according to embodiments.

[0073] FIG. 32 is a flow diagram of a method of accessing an extravascular space, according to embodiments.

[0074] FIGS. 33A and 33B are schematic diagrams of cross-sectional side views of a catheter in a head of a subject, according to embodiments.

[0075] FIG. 34A is a schematic diagram of a cross-sectional side view of a catheter, according to embodiments. FIGS. 34B-34D are schematic cross-sectional views of a catheter assembly in a head of a subject, according to embodiments.

[0076] FIG. 35 A is a schematic side view of perforating devices, according to embodiments. FIGS. 35B and 35C are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments.

[0077] FIGS. 36A-36D are schematic side and cross-sectional top views of catheter assemblies, according to embodiments.

[0078] FIGS. 37A-37D are schematic side and cross-sectional top views of catheter assemblies, according to embodiments. FIG. 37E is a schematic side view of a catheter assembly, according to embodiments.

[0079] FIGS. 38A-38E are schematic side views of catheter assemblies, according to embodiments.

[0080] FIGS. 39A-39D are schematic cross-sectional side views of a method of accessing an extravascular space, according to embodiments.

[0081] FIGS. 40A-40C are schematic cross-sectional side views of a method of accessing an extravascular space, according to embodiments.

[0082] FIGS. 41A-41C are schematic cross-sectional side views of a catheter assembly and a method of accessing an extravascular space, according to embodiments. FIG. 4 ID is a schematic cross-sectional side view of a method of accessing an extravascular space, according to embodiments.

[0083] FIGS. 42A and 42B are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments.

[0084] FIGS. 43 A and 43B are schematic cross-sectional top and side views of catheter assemblies, according to embodiments.

[0085] FIGS. 44A-44C are schematic cross-sectional side views of catheter assemblies, according to embodiments.

[0086] FIG. 45 A are schematic side views of perforating elements, according to embodiments. FIG. 45B are schematic cross-sectional side views of a perforating element in a head of a subject, according to embodiments.

[0087] FIGS. 46A-46E and 46B are schematic cross-sectional side views of a perforating element and catheter assembly in a head of a subject, according to embodiments.

[0088] FIGS. 47A and 47B are schematic cross-sectional side views of a catheter assembly in a head of a subject, according to embodiments. FIG. 47C is a schematic cross-sectional top view of a catheter assembly in a head of a subject, according to embodiments. FIG. 47D is a cross-sectional side view of the catheter assembly, according to embodiments.

[0089] FIG. 48 are schematic side and front views of perforating elements, according to embodiments.

[0090] FIGS. 49A-49G are schematic cross-sectional side views of catheter assemblies in a head of a subject, according to embodiments. FIG. 49H is a detailed cross-sectional side view of a proximal end of a catheter assembly configured to be coupled to a catheter, according to embodiments.

[0091] FIGS. 50A and 50C are schematic cross-sectional top views of a catheter assembly in a head of a subject, according to embodiments. FIG. 50B is a schematic cross-sectional side view of a catheter assembly in a head of a subject, according to embodiments.

[0092] FIG. 51 A are schematic side views of a catheter and a perforating element, according to embodiments. FIG. 5 IB are schematic cross-sectional side views of a catheter and a perforating element in a head of a subject, according to embodiments.

[0093] FIG. 52A is a schematic cross-sectional side view of an occlusion device, according to embodiments. FIG. 52B is a schematic cross-sectional side view of a catheter assembly and an occlusion device in a head of a subject, according to embodiments.

[0094] FIG. 53 are schematic side views of an occlusion device in a head of a subject, according to embodiments.

[0095] FIG. 54 are X-ray images of a middle meningeal artery (MMA) and a hemostatic device, according to embodiments.

[0096] FIG. 55 are schematic perspective and side views of pressure sensor-based devices, according to embodiments.

[0097] FIGS. 56A-56E are schematic cross-sectional views of a catheter assembly in a head of a subject, according to embodiments.

[0098] FIG. 57 is a schematic cross-sectional view of a catheter assembly in a head of a subject, according to embodiments.

[0099] FIG. 58 is a schematic cross-sectional side view of a handle assembly, according to embodiments.

[0100] FIG. 59 is a schematic cross-sectional side view of an indwelling catheter assembly in a head of a subject, according to embodiments.

[0101] FIGS. 60A-60B are coronal cross-sectional views of a head of a subject, according to embodiments.

[0102] FIG. 61 A is a schematic cross-sectional axial view of a head of a subject, according to embodiments. FIG. 61B is a schematic cross-sectional coronal view of a head of a subject, according to embodiments. FIG. 61C is a schematic cross-sectional sagittal view of a head of a subject, according to embodiments. FIG. 6 ID is a diagram of a coordinate system, according to embodiments. FIG. 6 IE is a schematic side view of imaging of a head of a subject, according to embodiments.

[0103] FIG. 62 is a flow diagram of a method of accessing an extravascular space, according to embodiments.

[0104] FIGS. 63 A-63D are schematic cross-sectional views of a catheter assembly in a head of a subject, according to embodiments.

[0105] FIG. 64A is a schematic cross-sectional view of a catheter assembly, according to embodiments. FIG. 64B is a schematic perspective view of a catheter assembly, according to embodiments. FIG. 64C is a schematic cross-sectional axial view of a catheter assembly in a head of a subject, according to embodiments. FIG. 64D is a schematic cross-sectional coronal view of a catheter assembly in a head of a subject, according to embodiments. FIG. 64E is a schematic cross-sectional sagittal view of a catheter assembly in a head of a subject, according to embodiments.

[0106] FIG. 65 A is a schematic side view of a catheter assembly in a head of a subject, according to embodiments. FIG. 65B is a schematic side view of a catheter assembly in first and second configurations, according to embodiments.

[0107] FIGS. 66A-66C are schematic diagrams of a catheter assembly, according to embodiments.

[0108] FIGS. 67A-67E are schematic cross-sectional views of a shaft of a catheter assembly, according to embodiments.

[0109] FIGS. 68A-68C are schematic diagrams of catheter assemblies in head of a subject, according to embodiments.DETAILED DESCRIPTION

[0110] Described here are systems, devices, and methods for use in minimally invasive surgical procedures enabling transvascular neurosurgery without opening the skull or spine. For example, the systems, devices, and methods described herein may improve access to an extravascular space (e.g., subdural space, epidural space, subarachnoid space, extravascular spinal intradural space, spinal cord space) and extravascular organ (e.g., brain, spinal cord, nerve roots) of a subject by: being performed under minimal sedation; reducing one or more of procedural complexity, sterile field management, and time; enabling continual use of anti coagulation and antiplatelet medications; providing quicker post-surgical recovery and shortening hospitalization time; and reducing complications when compared to conventional open surgical procedures. For example, access to an extravascular space may include navigation within a body compartment without blood extravasation while the blood vessel is patent and absent tissue damage (e.g., due to perforation). In some embodiments, access to the subdural space may be used to facilitate drainage of subdural fluid.

[0111] While conventional solutions require separate procedures to evacuate a subdural hematoma (SDH) and to embolize an artery, the systems, devices, and methods disclosed herein may be performed within a single endovascular approach. For example, the systems, devices, and methods described herein may facilitate immediate brain decompression through transvascular drainage of an SDH and prevention of hematoma recurrence throughembolization of the MMA within the same procedure, thereby obviating the need for a second and separate invasive open surgical procedure.

[0112] In some embodiments, a method of accessing an intracranial extravascular space of a patient may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. A wall of the intracranial vessel may be obliquely perforated using the perforating element while the perforating element extends substantially parallel to the intracranial vessel to form an opening into the intracranial extravascular space.

[0113] In some embodiments, a method of forming a passageway through a wall of an intracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within the intracranial vessel. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. The perforating element may be directionally guided towards a wall of the intracranial vessel and the dura using anatomical features proximate to the intracranial vessel. The wall of the intracranial vessel and the dura may be obliquely perforated using the perforating element while the perforating element is directionally guided toward the wall of the intracranial vessel and the dura to form a passageway into the intracranial extravascular space.

[0114] In some embodiments, a method of forming a passageway through a wall of an intracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. A wall of the intracranial vessel and the dura may be perforated using the perforating element to form a passageway into the intracranial extravascular space. A dilation device may be advanced over the perforating element through the passageway. An expandable member of the dilation device may be transitioned into an expanded configuration to enlarge the passageway.

[0115] In some embodiments, an apparatus may comprise an elongate body (e.g., catheter) defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel. A plurality of apertures may be disposed on the distal end of the elongate body. The plurality of apertures may be configured to drain fluid or matter from an intracranial extravascular space. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be advanced into the intracranial vessel to perforate a wall of the intracranial vessel and to form a passageway into the intracranial extravascular space. The elongate body may be further configured to be advanced over the perforating device into the intracranial extravascular space such that the plurality of apertures can drain fluid or matter from the intracranial extravascular space.

[0116] In some embodiments, an apparatus may comprise an elongate body defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel, the lumen including a distal curve. An opening may be disposed on the distal end of the elongate body, the opening being in communication with the lumen. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be guided via the distal curve and out through the opening toward a wall of the intracranial vessel to perforate the wall and form a passageway into the intracranial extravascular space.

[0117] In some embodiments, an apparatus may comprise an elongate body (e.g., catheter) defining a lumen, the elongate body including a distal end configured to be advanced through an intracranial vessel and into an intracranial extravascular space over a shaft. The elongate body may further include a proximal end configured to be coupled to a source of therapy such that the therapy can be delivered to the intracranial extravascular space via the catheter. An anchor may be coupled to the elongate body and configured to expand to releasably anchor the elongate body to tissue.

[0118] In some embodiments, systems and devices may comprise a first catheter configured to traverse through a blood vessel and perforate through a vessel wall and dura without injuring the brain. The first catheter may then be advanced atraumatically through one or perforations through an epidural space and subdural space and into an SDH fordrainage using a second catheter. Once the viscous fluid of the SDH has been evacuated, the second catheter or a third catheter may be used to occlude the arteriotomy formed by the first catheter without bleeding. Some of the endovascular systems described herein may be used to perform surgical procedures including one or more of endovascular evacuation, embolization, drug or biological delivery, device delivery (e.g., including electrodes), tissue sampling, and combinations thereof.

[0119] In some embodiments, a method may comprise positioning a distal end of a catheter disposed within an intracranial vessel of a subject near a target location, and advancing a perforating device (e.g., shaft) through a lumen of the catheter. The perforating device may be extended out of the distal end of the catheter to create an opening through the wall of the vessel and dura of the subject and into an extravascular intracranial space. The catheter may be advanced over the perforating device and into the extravascular intracranial space. The SDH will then drain or negative pressure may be applied to a lumen of the catheter to suction fluid from the SDH.

[0120] In some embodiments, an apparatus may comprise a perforating device configured to be slidably disposed within a lumen of a catheter. The perforating device may be configured to be advanced distally from a distal end of the catheter and into a blood vessel of a subject. In some embodiments, the perforating device may include a perforating tip configured to form an opening through a wall of the blood vessel and dura of the subject and into an extravascular space of the subject. A drainage catheter may be configured to advance through vasculature in a delivery configuration and transition to an expanded treatment configuration within an SDH for drainage.

[0121] In addition to examples and embodiments described herein, other suitable examples of systems, devices, and methods are described in International Application No.PCT / US2021 / 029276, filed on April 27, 2021, and International Application No. PCT / US2023 / 078841, filed on November 6, 2023, the disclosure of each of which is hereby incorporated by reference in their entirety.

[0122] Systems, devices, and methods described herein can be used to access an extravascular space of a subject, including, for example, intradural extravascular spaces along a spinal cord of a subject or in a brain of a subject. FIG. 1 is a schematic coronal cross- sectional view of a subject 100 including a skull 110 encasing each of a brain 120, a duramater (dura) 130, a superior sagittal sinus (SSS) 140, and a subdural hematoma (SDH) 150. An SDH is a type of bleeding in which a collection of blood, usually associated with a traumatic brain injury, gathers between the inner layer of the dura mater 130 and the arachnoid mater of the meninges surrounding the brain 120. It usually results from tears in bridging veins that cross the subdural space followed by persistent bleeding from microvessels. Subdural hematomas may cause an increase in the pressure inside the skull, which in turn can cause compression of and damage to delicate brain tissue. The SDH 150 is depicted in FIG. 1 between the brain 120 and the dura 130 and typically faces the convexity of the cerebral hemisphere. Though not shown in FIG. 1, an SDH 150 may be in proximity to the vascular structures of the dura 130 including a middle meningeal artery (MMA), a middle meningeal vein (MMV), a superior sagittal sinus (SSS) 140, an inferior sagittal sinus (IS S), a superior petrosal sinus (SPS), and a transverse-sigmoid junction or the transverse sinus (TS).

[0123] The SSS 140 is a midline vein without valves that courses along the falx cerebri from the vicinity of the crista galli to the confluence of sinuses at the posterior cranium. The SSS 140 faces both cerebral hemispheres and generally has a length of between about 31 cm and about 38 cm, and receives between about 12 and about 20 venous tributaries from the left and right cerebral hemispheres. Generally, the SSS 140 has a triangular shape with a width between about 3 mm and about 18 mm and a height between about 3 mm and about 14 mm. The cross-sectional area of the SSS 140 may be between about 15 mm2and about 90 mm2, and the angle between the sinus wall and a midline may be between about 25° and about 65°. A typical distance between the SSS 140 and the subdural hematoma 150 is usually less than about 35 mm. The SSS 140 is typically surrounded by dura 130 and is separated from the brain 120 by the arachnoid and subarachnoid space filled with cerebrospinal fluid. Brain atrophy may result in widened spaces between the SSS 140 and the brain 120. For example, a space between a surface of the brain 120 and the dura 130 may be between about 1 mm and about 20 mm (e.g., between about 2 mm and about 8 mm) for subjects having chronic SDH.

[0124] It may further be helpful to briefly discuss conventional approaches to treatment of subdural hematomas. FIG. 2 depicts a schematic perspective view 200 of a subject undergoing surgical evacuation of a hematoma. In particular, a first bore hole 210 and a second bore hole 212 are formed in the subject’s skull in proximity to a hematoma 230, shown for the sake of illustration in FIG. 2 without the overlying portion of the skull. Salinesolution 220 may be introduced into the first bore hole 210 such that fluid 232 (including hematoma 230) may flow out of the second bore hole 212.

[0125] In some embodiments, a single endovascular approach may be performed to access an extravascular space of a subject. For example, FIGS. 3A-3D are lateral and cross-sectional views of a head 300, 302, 304, 306 of a subject. The head 300 of FIG. 3 A depicts a skull 310, an internal maxillary artery 340 coupled to a middle meningeal artery (MMA) 342, and a subdural hematoma (SDH) 350. In some embodiments, a sheath (e.g., sleeve, delivery catheter, guide catheter, intermediate catheter) 360 may be advanced through one or more of the internal maxillary artery 340 and the MMA 342. A catheter 362 (e.g., embolization catheter) may be advanced from a distal end of the sheath 360 and configured to deliver a hemostatic element 370 (e.g., occlusion element, embolic material, embolic fluid, micro particles, coil) into a set of branches of the MMA 342 for reducing (e.g., occluding) the hemorrhaged vessels of the MMA 342. In some embodiments, the sheath 360 may be advanced through any suitable vascular access point (e.g., peripheral arterial vasculature) such as the femoral artery (e.g., groin), radial artery (e.g., wrist), brachial artery, carotid artery, and the like.

[0126] The MMA 342 is generally the third branch of the first portion of the internal maxillary artery 340. Each side of the head 300 may include an MMA 342 that branches off the internal maxillary artery 340 in the infratemporal fossa, through the foramen spinosum and into the intracranial compartment where the MMA 342 deflects anteriorly and laterally at an angle between about 60° and about 120° relative to a longitudinal axis of the foramen spinosum.

[0127] As shown in FIGS. 3B-3D, the MMA 342 is typically located on the epidural side of the dura 330. The MMA 342 generally bifurcates parallel to the dura 330. The MMA 342 may supply blood to the dura 330, the outer meningeal layer, and the calvaria. A main trunk of the MMA 342 may generally be between about 14 mm and about 34 mm. The MMA 342 generally bifurcates into a frontal and a parietal branch (as well as other minor branches). A mean diameter of the main trunk of the MMA 342 may be between about 0.6 mm and about 1.2 mm. However, subjects having eSDH may have a mean diameter of the main trunk of the MMA 342 between about 1 mm and about 2 mm. The MMA 342 may supply blood to pathological membranes that maintain and / or expand the SDH. FIG. 3C depicts a catheter362 and a perforating device 364 (e.g., shaft) advanced into the MMA 342 between the dura 330 and skull 310. The perforating device 364 may be configured to be slidably disposed within a lumen of the catheter 362. As described in more detail herein, the perforating device 364 may be configured to form an opening through a wall of the blood vessel (e.g., MMA 342) and dura 330 and into an extravascular space of the subject to facilitate access to the intradural space between the dura 330 and the brain 320. FIG. 3D depicts delivery of a hemostatic element 370 into the MMA 342 from a lumen of the catheter 362.

[0128] Systems, devices, and methods described herein can be used to access an extravascular space of a subject using an endovascular approach including one or more arterial access sites such as a femoral artery, radial artery, carotid artery, subclavian artery, and axillary artery. For example, systems and devices described herein may be advanced through vasculature to common carotid arteries such as the MMA. For example, FIG. 4 is a lateral view 400 of a head of a subject including bone (e.g., skull) 410, internal maxillary artery 420, and middle meningeal artery (MMA) 430. As shown in FIG. 4, a delivery catheter (e.g., sheath) 440 may be disposed within the internal maxillary artery 420 and a proximal portion of the MMA 430. A catheter 450 (e.g., drainage catheter, suction catheter, occlusion catheter) as described in more detail herein may be slidably disposed within a lumen of the delivery catheter 440 and advanced from a distal end of the delivery catheter 440. The catheter 450 may be configured to be advanced into a subdural hematoma (SDH) 420 from the MMA 430. As described in more detail herein, suction 420 (e.g., aspiration, drainage) of the SDH 420 may be performed through a lumen of the catheter 450.I. SYSTEM AND DEVICES

[0129] Systems and devices described herein can be configured to enable transvascular surgery including, but not limited to, improving access to an extravascular space, treatment of a subdural hematoma, delivery of a drug or therapeutic agent, delivery of a device (e.g., sensor, electrode, biopsy device, ablation device, catheter, draining system), tissue sampling, implantation of a device, etc. FIG. 5 is a schematic block diagram of a system 500 including a catheter assembly 502, a vacuum source 550, a signal generator 560, and a visualization device 570. The catheter assembly 502 may be configured to form an opening from a blood vessel to an extravascular space of a subject. In some embodiments, the catheter assembly 502 may include a catheter 510 (e.g., elongate body), a perforating device (e.g., shaft) 520, ahemostatic device 530, one or more optional sensors 540, and an optional sheath (e.g., delivery catheter, guide catheter) (not depicted).

[0130] In some embodiments, one or more components of the catheter assembly 502 may include one or more of a hypotube, a single solid rod, multiple rods, a bundle, a tube (with one or more lumens), shaft strands, a cable (e.g., two or more wires running side by side, bonded, twisted, or braided), a coil, a braid, combinations thereof, and the like. In some embodiments, one or more components of the catheter assembly 502 may include one or more of stainless steel, a superelastic material, nitinol, a nitinol alloy, silver, titanium, copper, cobalt chromium, nickel chromium, platinum iridium, polymer, nylon, polyamides, fluoropolymers, polyolefins, polythetrafluoroethylene, high density polyethylene, polyurethanes and polyimides, ceramic, bio-absorbable or dissolvable material, combinations thereof, and the like.

[0131] In some embodiments, one or more components of the catheter assembly 502 may have a tip bending stiffness between about 0.0002 lb. / in2and about 0.15 lb. / in2, inclusive of all ranges and subranges therebetween. The components of the catheter assembly 502 may have a variable tip bending stiffness along a respective length of each component.

[0132] In some embodiments, one or more components of the catheter assembly 502 may include scoring configured to increase flexibility (e.g., to traverse the curves of a foramen spinosum). The scoring may include, but is not limited to, a spiral scoring pattern (e.g., continuous, interrupted), a radial scoring pattern, a bespoke scoring pattern, a radial ring pattern, a longitudinal scoring, an oblique scoring, a window, a tab, a hole, combinations thereof, and the like.

[0133] In some embodiments, one or more components of the catheter assembly 502 may have a cross-sectional shape including, but not limited to, a circle, an oval, a square, a star, a diamond, a rectangle, a flat shape, combinations thereof, and the like. One or more of a cross- sectional shape and diameter of the catheter assembly 502 may vary along a length of the catheter assembly 502.Catheter

[0134] The catheter 510 (e.g., elongate body) can be configured to remove fluid from and / or deliver fluids or devices to an extravascular space. In some embodiments, a catheter assembly 502 may be sufficiently small and flexible to navigate intracranially by crossing multiple complex angles and have high and precise torqueability to direct a perforation towards the subdural space from an access site more than about 170 cm away. These challenges are exacerbated by subject variations including the degree of aortic and meningo- cervical vascular tortuosity, the location of the arterial perforation point along a squama of a temporal bone, the fluid viscosity, and the presence of thick membranes and septations.

[0135] In some embodiments, the catheter 510 (e.g., elongate body) may be configured to transition between different configurations such as a delivery configuration (e.g., first configuration) for advancement through vasculature and a treatment configuration (e.g., second configuration) for removal of an SDH. For example, the catheter 510 in the delivery configuration may have a constrained shape configured to minimize size and facilitate delivery of the catheter 510 to a treatment site. In the delivery configuration, the catheter 510 may traverse tortuous vasculature that follows the curvature of the skull and the relatively long intravascular corridors in the epidural space or dura such that the catheter 510 has a constrained, generally linear shape. The catheter 510 in the treatment configuration may have an expanded shape configured to allow fluid and material to be efficiently removed from the SDH, as described in more detail herein.

[0136] As described in more detail herein, a catheter 510 (e.g., elongate body) may define a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel. A plurality of apertures may be disposed on the distal end of the elongate body. The plurality of apertures may be configured to drain fluid or matter from an intracranial extravascular space. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be advanced into the intracranial vessel to perforate a wall of the intracranial vessel and to form a passageway into the intracranial extravascular space. The elongate body may be further configured to be advanced over the perforating device into the intracranial extravascular space such that the plurality of apertures can drain fluid or matter from the intracranial extravascular space. Forexample, the catheter 510 may include one or more apertures 514 and a coupling portion 516. The catheter 510 may define a lumen (having a corresponding inner diameter) extending from a proximal end to a distal end of the catheter 510. In some embodiments, one or more apertures 514 may be disposed along a distal portion 512 of the catheter 510. A proximal portion 513 may be coupled to the distal portion 512. In some embodiments, the catheter 510 may include a plurality of lumens and one or more distal openings. In some embodiments, one or more of the lumens and / or apertures 514 may be configured for one or more of drainage, suction, and fluid delivery. In some embodiments, the coupling portion 516 may be configured to releasably couple to one or more components of the catheter assembly 502 such as a guidewire and a perforating device 520 (e.g., shaft, perforating element 524).

[0137] In some embodiments, a shape of an aperture 514 may comprise one or more of a circle, an oval, an ellipse, a square, a star, a diamond, a rectangle, longitudinal (e.g., slit), an elongate shape, combinations thereof, and the like. In some embodiments, a plurality of apertures 514 may be distributed homogenously along a predetermined length and / or circumference of the catheter 510. For example, the plurality of apertures 514 may be distributed around a complete circumference of the catheter 510 with the apertures 514 evenly spaced apart from each other. Alternatively, the plurality of apertures 514 may be distributed along a length and circumference of the catheter 510 in a spiral pattern with a predetermined width and spacing. In some embodiments, one or more of a size and shape of the apertures 514 may be based on a location of the aperture 514 along a length of the catheter 510. For example, a size of an aperture 514 may increase in a distal direction of the catheter 510 such that smaller apertures are disposed proximally and larger apertures are disposed distally (or vice versa). Similarly, a shape of an aperture 514 may be based on a location along a length of the catheter 510. For example, a proximal portion 513 of the catheter 510 may comprise a first aperture shape (e.g., slits) and a distal portion 512 of the catheter 510 may comprise a second aperture shape (e.g., circular). In some embodiments, a density of apertures 514 may be based on a location along a length of the catheter 510. For example, a density of apertures 514 may increase in a distal direction of the catheter 510 such that less apertures are disposed proximally and more apertures are disposed distally (or vice versa).

[0138] In some embodiments, the catheter 510 may comprise one or more fiducials 518 configured to aid one or more of navigation, positioning, and visualization of the catheter510. For example, a distal portion 512 of the catheter 510 may include one or more fiducials 518 at a distal end of the distal portion 512, a proximal end of the distal portion 512, and / or a portion there-b etween. The position of the fiducials 518 relative to each other may indicate, for example, the location of the catheter 510 within the body (e.g., within the MMA, within the subdural space). Furthermore, the relative positions of the fiducials 518 may indicate a configuration of the catheter 518. For example, a linear set of fiducials 518 may indicate that the catheter 518 is in a delivery configuration (e.g., first configuration) while the fiducials 518 having a non-linear shape may indicate that the catheter 518 is in a treatment configuration (e.g., second configuration) where a distal portion 512 of the catheter 510 is biased towards its unconstrained shape. In some embodiments, the fiducial 518 may comprise one or more of a radiopaque element such as gold, tungsten, barium sulfate, and alloys thereof. The non-linear shaped section may include one or more fiducials 518 (e.g., markers) configured to indicate a shape or a location of the non-linear shaped section.

[0139] The catheter 510 can be configured to have high flexibility. In some embodiments, the catheter 510 has sufficient flexibility so as to take the shape of a perforating device 520 slidably disposed therein. However, the shape of the catheter 510 and perforating device 520 may be constrained by the shape of the lumen or body cavity (e.g., artery, subdural space) in which the catheter 510 is disposed.

[0140] In some embodiments, an inner diameter of a catheter may be maximized while ensuring navigation of the catheter through an intracranial vessel to a perforation point. For example, for a perforation point in the MMA, the catheter 510 may have a distal inner diameter of between about 0.005 inches and about 0.060 inches, and between about 0.012 inches and about 0.03 inches, inclusive of all ranges and subranges therebetween.

[0141] In some embodiments, a catheter configured to reach a radial and / or a femoral access point may have a working length of at least about 120 cm, and between about 130 cm and 170 cm, inclusive of all ranges and subranges therebetween. In some embodiments, the catheter 510 may be configured to advance through a minimal curve angle of 70° without kinking to facilitate advancement into an intracranial compartment through a foramen spinosum.

[0142] In some embodiments, the catheter 510 has sufficient column strength to generate greater than about 1 N forward load without kinking, ovalizing, or herniating into a vessel(e.g., branching artery) to perforate the MMA and dura, as well as receive a negative pressure of greater than about 29 inHg without collapsing for fluid removal.

[0143] In some embodiments, an inner and / or outer diameter of the catheter 510 may be tapered. In some embodiments, an inner diameter at a distal portion 512 (e.g., distal end) of the catheter 510 may be smaller than an inner diameter at a proximal portion 513 (e.g., proximal end) of the catheter 510, e.g., to facilitate increased fluid flow (e.g., during suction).

[0144] In some embodiments, the catheter 510 may be slidably disposed within a lumen of a sheath. For example, the sheath may include one or more of a guide catheter, intermediate delivery catheter, and a microcatheter.

[0145] In some embodiments, one or more components of the catheter 510 may include one or more of a coating (e.g., hydrophobic coating) configured to decrease transvascular bleeding around the catheter 510. For example, a catheter 510 coating may be composed of polymers including, but not limited to, polystyrene (PS), polybutadiene (PB), polyisoprene (PI), poly(methyl methacrylate) (PMMA), poly(methylacrylate) (PMA), polypropylene oxide) (PPO), poly(hydroxyethylmethacrylate) (PHEMA), poly(vinyl ether) (PVE), poly(vinyl methyl ether) (PVME), poly(vinyl butyl ether) (PVBE), polyimide and poly(dimethylsiloxane) (PDMS), and poly(N-isopropylacrylamide) (PNIPAM). In some embodiments, the coating of the catheter 510 may vary in composition, thickness, and properties along a length of the catheter 510.

[0146] In some embodiments, an inner diameter of the catheter 510 may include a coating (e.g., hydrophilic coating) configured to decrease resistance to fluid flow and enhance drainage of an SDH. For example, the inner diameter coating of the catheter 510 may be composed of polymers including, but not limited to, poly(lactams) such as polyvinylpyrrolidone (PVP), polyurethane, homopolymers and copolymers of acrylic acid and methacrylic acid, polyvinyl alcohol, polyvinyl ether, maleic anhydride copolymers, polyesters, vinylamines, polyethyleneimines, Polyethylene oxide, poly (carboxylic acid), polyamide, polyanhydride, polyphosphazene, cellulose (e.g., methylcellulose), carboxymethylcellulose, hydroxymethylcellulose, and hydroxypropylcellulose, heparin, dextran, polypeptides (e.g., collagen, fibrin, and elastin), sugars (e.g., chitosan), hyaluronic acid, alginate, gelatin, and chitin, polyesters (e.g., Rirakuchido, polyglycolide, polycaprolactones, polypeptides). Additionally or alternatively, an inner diameter coating ofthe catheter 510 may be configured to reduce thrombosis and occlusion. For example, the inner diameter coating of the catheter 510 may comprise one or more of heparin, an anticoagulant (e.g., Dabigatran, Rivaroxaban, Apixaban, Warfarin, Enoxaparin, Edoxaban, Aspirin, Arixtra), a thrombolytic substance, a thrombin inhibitor, combinations thereof, and the like.

[0147] In some embodiments, at least one portion (e.g., distal portion 512, proximal portion 513) of an outer surface of the catheter 510 may include a coating (e.g., hydrophilic coating, hydrophobic coating). For example, a distal portion 512 of the catheter 510 may comprise a hydrophilic coating configured to facilitate transvascular access. In some embodiments, the distal portion 512 may comprise a length from a distal end of the catheter 510 of up to about 10 cm, of up to about 8 cm, of up to about 5 cm, of up to about 3 cm, of up to about 1 cm, inclusive of all ranges and subranges therebetween. In some embodiments, a proximal portion of the catheter 510 may comprise a hydrophobic coating configured to minimize bleeding at a transvascular access site. In some embodiments, the proximal portion 513 may comprise a length of up to about 10 cm, of up to about 8 cm, of up to about 5 cm, of up to about 3 cm, of up to about 1 cm, inclusive of all ranges and subranges therebetween.

[0148] FIG. 6A is a schematic side view of a catheter 600 and FIG. 6B is a detailed cross- sectional diagram of the catheter 600 including an outer portion 610 (e.g., outer layer) and an inner portion 620 (e.g., inner layer). In some embodiments, the outer portion 610 may include one or more structures 630 (e.g., reinforcements) configured to modify one or more characteristics of the catheter 600 such as a strength, flexibility, pushability, torqueability, and the like. The structures 630 may vary along a length of the catheter 600 to provide different characteristics to different portions (e.g., distal portion, proximal portion) of the catheter 600. In some embodiments, the structure 630 may comprise one or more materials and elements different from the outer portion 610. In some embodiments, a coating 640 may be disposed over one or more portions of the outer portion 610. The coating 640 may be configured to increase or decrease lubricity. For example, the coating 640 may be hydrophilic or hydrophobic. In some embodiments, the catheter 600 may comprise one or more lumens 650. A distal portion of the catheter 610 may be coupled to a connector (e.g., luer) configured to connect to a fluid source (e.g., syringe, tubing, aspirator) such as for fluid irrigation, drainage, and suction. One or more fiducials 602 (e.g., radiopaque element) may be disposed at a distal portion of the catheter 600.

[0149] In some embodiments, one or more components of the catheter 600 may include one or more of a hypotube, a single solid rod, multiple rods, a bundle, a tube (with one or more lumens), shaft strands, a cable (e.g., two or more wires running side by side, bonded, twisted or braided), a coil, a braid, combinations thereof, and the like. In some embodiments, one or more components of the catheter 600 may include one or more of a polymer, polytetrafluoroethylene (PTFE), polyethylene block amide (PEB AX), polyurethanes, pellethane, tecothane, combinations thereof, and the like.

[0150] In some embodiments, one or more structures 630 may comprise a fiducial (e.g., radiopaque element), a mesh, and a metal reinforcement including one or more of stainless steel, nitinol, tungsten, and polymer reinforcement. In some embodiments, the structure 630 may include one or more of a braid, a coil, a cut tube, and slots. For example, slots in the outer portion 610 of the catheter 600 may be configured to modify a flexibility of the catheter 600. In some embodiments, one or more apertures (not shown) may be disposed within an outer portion 610 and / or inner portion 620 of a catheter 600. For example, the apertures may be disposed within a structure 630 (e.g., reinforcement) configured as a filter. In some embodiments, one or more of a braid, a coil, a slotted hypotube, and combinations thereof may define one or more apertures. In this manner, the structural integrity and the mechanical characteristics (e.g., pushability, kink resistance) of the catheter 600 may be maintained. Furthermore, the apertures having the structure(s) 630 may be configured to reduce obstruction by functioning as a barrier for fluid (e.g., particulate matter) inflow into the catheter lumen 650. In some embodiments, the inner portion 610 may be configured to facilitate the smooth advancement of one or more of a perforating device and guidewire within a lumen of the catheter independent of an area of the apertures. For example, a predetermined number of apertures (including the structure(s) 630 and the inner portion 620) may have a diameter of between about 200 pm and about 500pm at a distal portion of the catheter 600. The apertures may be located between about 2 cm and about 5 cm from a distal end of the catheter 600.

[0151] In some embodiments, apertures may be disposed circumferentially around the catheter to enable aspiration of fluid into the catheter lumen 650 through the catheter sidewall (e.g., outer portion 630, inner portion 620). This may facilitate fluid flow even when a distal opening of the catheter (or least a circumferential arc of the distal opening) is occluded by particulate matter (e.g., membranes). That is, the apertures may be configured to maintain andaugment the flow (e.g., drainage, suction) of subdural hematoma into a lumen of the catheter 600 even when the distal tip portion is occluded.

[0152] In some embodiments, a filter (e.g., mesh) may be disposed between the outer portion 610 and the inner portion 620, and / or over an aperture of the catheter. The mesh may be configured to allow fluid to enter the catheter lumen during aspiration and prevent particulate matter having a predetermined size (e.g., clots, brain tissue, membranes, septations) from entering the lumen, thereby preventing occlusions. The mesh may comprise one or more of a textile, polymer braid, microaggregate blood filter, Pall SQ40, thin film nitinol, combinations thereof, and the like.

[0153] In some embodiments, the inner portion 620 may comprise a polymer (e.g., inert, lubricious) such as PTFE and the outer portion 610 may comprise a combination of polymer materials of differing hardness (e.g., durometer). For example, a proximal portion of the outer portion 610 may comprise a first material having a first durometer configured to facilitate pushability and a distal portion of the outer portion 610 may comprise a second material having a second durometer less than the first durometer (e.g., softer than the proximal portion) to promote flexibility and facilitate navigation of tortuous distal vessels. In some embodiments, a distal tip of the catheter 600 may have an atraumatic shape including blunt, squared, rounded, tapered, combinations thereof, and the like. In some embodiments, a distal tip of the catheter 600 may be angled (e.g., beveled) to aid transvascular advancement of the catheter 600 through the dura and into a subdural space.

[0154] FIG. 7A is a schematic side view of a catheter 700 including one or more apertures 710 and one or more lumens 720. FIG. 7B is a cross-sectional front view of a catheter 702 having a single lumen 722 and a plurality of apertures 710. FIG. 7C is a cross-sectional front view of a catheter 704 having a plurality of lumens 724, 726 where the plurality of apertures 710 are fluidically coupled to a respective lumen of the plurality of lumens 726 disposed, for example, along a circumference of the catheter 704. A central lumen 724 may extend along a longitudinal axis of the catheter 704. The central lumen 724 may have a larger diameter than each of the plurality of lumens 726. In some embodiments, one or more of the lumens 722, 724, 726 may be configured for one or more of drainage, suction (e.g., aspiration), and fluid delivery. In some embodiments, a distal portion of the catheters 700, 702, 704 may comprise one or more apertures 710 at a distal end of a respective catheter 700, 702, 704 and along arespective sidewall of the catheter 700, 702, 704. In some embodiments, a distal portion of the catheter 700, 702, 704 may comprise a length from a distal end of the catheter 700, 702, 704 of up to about 10 cm, of up to about 8 cm, of up to about 5 cm, of up to about 3 cm, of up to about 1 cm, inclusive of all ranges and subranges therebetween. For example, the plurality of apertures may be disposed on a distal length of the elongate body having a length of between about 1 cm and about 10 cm, inclusive of all ranges and subranges therebetween.

[0155] In a similar manner as described with respect to apertures 514, a shape of the apertures 710 may comprise one or more of a circle, an oval, an ellipse, a square, a star, a diamond, a rectangle, longitudinal or elongate (e.g., slit), combinations thereof, and the like. In some embodiments, the plurality of apertures 710 may be distributed homogenously along a predetermined length and / or circumference of a catheter 700, 702, 704. For example, the plurality of apertures 710 may be distributed around a complete circumference of the catheter 700, 702, 704 with the apertures 710 evenly spaced apart from each other. Alternatively, the plurality of apertures 710 may be distributed along a length and a circumference of the catheter 710 in a spiral pattern with a predetermined width and spacing. In some embodiments, one or more of a size and shape of the apertures 710 may be based on a location of the aperture 710 along a length of the catheter 700, 702, 704. For example, a size of an aperture 710 may increase in a distal direction of the catheter 700, 702, 704 such that smaller apertures are disposed proximally and larger apertures are disposed distally (or vice versa).

[0156] In some embodiments, a distal portion of the catheter 700, 702, 704 may have between about 1 aperture and about 1,000 apertures, between about 1 aperture and about 800 apertures, between about 1 aperture and about 600 apertures, between about 1 aperture and about 500 apertures, between about 1 aperture and about 300 apertures, between about 1 aperture and about 100 apertures, between about 1 aperture and about 50 apertures, between about 1 aperture and about 20 apertures, between about 1 aperture and about 10 apertures, between about 1 aperture and about 5 apertures, between about 50 apertures and about 800 apertures, between about 100 apertures and about 600 apertures, between about 200 apertures and about 500 apertures, and between about 300 apertures and about 400 apertures, inclusive of all ranges and subranges therebetween.

[0157] In some embodiments, the apertures described herein (e.g., apertures 514, 710) may be formed by one or more of drilling, skiving, and laser ablation such that the apertures have atraumatic (e.g., tapered, rounded) edges. In some embodiments, the plurality of apertures may have the same or different diameters. For example, a diameter of an aperture of at least about 15 pm may allow fluid to enter a catheter 700, 702, 704 while also restricting (e.g., filtering) larger material (e.g., SDH membranes) from entering a lumen 720, 722, 726 of the catheter 700. Accordingly, a diameter of an aperture may be between about 15 pm and about 500 pm, between about 15 pm and about 300 pm, between about 15 pm and about 100 pm, between about 15 pm and about 50 pm, between about 15 pm and about 30 pm, between about 30 pm and about 50 pm, between about 50 pm and about 500 pm, between about 100 pm and about 500 pm, between about 150 pm and about 500 pm, between about 200 pm and about 500 pm, and between about 300 pm and about 500 pm, inclusive of all ranges and subranges therebetween.

[0158] FIG. 7D is a cross-sectional front view of a catheter 706 defining a lumen 720 and spaced apart apertures 710. For example, one or more apertures 710 may be disposed in planes at different degrees (e.g., 0 degrees, 90 degrees, 180 degrees, 270 degrees, etc.) around a circumference of the catheter 706. FIGS. 7E and 7F are schematic side views of catheters 706 including apertures 710. In some embodiments, apertures 710 of the catheter 700, 702, 704, 706 may be one or more of holes (e.g., circular holes), slots, and slits. As shown in FIG. 7E, the apertures 710 may be spaced apart (e.g., incrementally) along a length of the distal end of the catheter. For example, the apertures 710 may be disposed at different distances DI, D2, D3, D4, D5, D6, D7, and D8 from the distal end of the catheter. FIG. 7F shows a catheter 706 including one or more apertures 710 disposed at different degrees around the circumference of the catheter 706 and disposed incrementally at different distances (e.g., spaced apart) along the length of the catheter 706.

[0159] FIG. 7G includes schematic views of a catheter 700 including a braid 730, 740, 750 having respective apertures 710. Braid 730 includes a 1 wire over 2 wires under 2 wires pattern, braid 740 includes a 2 wires over 2 wires under 2 wires pattern, and braid 750 includes a 1 wire over 1 wire under 1 wire pattern. An aperture 710 between crossing wires (e.g., picks) may be quantified in terms of picks per inch (PPI) where a lower PPI corresponds to a larger the space between wires, thereby facilitating fluid flow therethrough. Conversely, a higher PPI corresponds to less space between wires, thereby reducing fluidflow and increasing filtering. In some embodiments, the catheters described herein (e.g., 510, 700, 702, 704, elongate body) may have a PPI of between about 80 PPI and about 130 PPI, between about 80 PPI and about 105 PPI, between about 105 PPI and about 130 PPI, and between about 90 PPI and about 110 PPI, inclusive of all ranges and subranges therebetween. In some embodiments, coils may be wrapped around an inner portion of a catheter without crossing itself. A space between coil wires may be defined as a pitch. A size of an aperture (e.g., about 15 pm or more) may be based on a pitch of a coil.

[0160] In some embodiments, a diameter of a catheter 800 may decrease monotonically distally along its length. For example, FIG. 8 is a schematic side view of a catheter 800 defining a lumen having a first portion 810 having a first diameter, a second portion 820 having a second diameter less than the first diameter, a third portion 830 having a third diameter less than the second diameter, and a fourth portion 840 having a fourth diameter less than the third diameter. Tapered portions 850 may couple adjacent portions to each other (e.g., the first portion 810 to the second portion 820, second portion 820 to the third portion 830, etc.). A larger diameter facilitates higher fluid flow rates such that the fluid flow rate through the catheter 800 increases proximally through the catheter 800. For example, aspiration of about 10 mL of fluid would take about 92 seconds assuming a viscosity of an SDH of about 3 mPas, an applied negative pressure (e.g., suction, vacuum) of about 90 kiloPascals (kPa), a catheter length of about 150 cm, a catheter inner diameter of about 0.027 inches, a first portion 810 having an inner diameter of about 0.042 inches for about 120 cm, a second portion 820 having an inner diameter of about 0.037 inches for about 10 cm, a third portion 830 having an inner diameter of about 0.035 inches for about 10 cm, and a fourth portion 840 having an inner diameter of about 10 cm.

[0161] In some embodiments, a distal tip portion of a catheter may be configured to transition to have a larger diameter than a proximal portion of the catheter. For example, FIG. 9 depicts a catheter 900 having a distal tip portion 910 having a funnel shape that may be preformed or configured to transition between a delivery configuration (e.g., unexpanded, tubular shape) and a treatment configuration (e.g., expanded, funnel shape). For example, the distal tip portion 910 may be constrained within a delivery catheter (not shown) and configured to expand when advanced distal to the delivery catheter. That is, the distal tip portion 910 may bias to a funnel configuration corresponding to a treatment configuration.

[0162] In some embodiments, one or more wires and rings may be configured to transition the distal tip portion of the catheter from a delivery configuration to an expanded configuration. For example, the wires 920 and rings 930 may be disposed between an outer portion and an inner portion of a catheter and coupled to an actuator (e.g., slider) disposed within a handle (not shown). One or more wires 920 may extend through a length of the catheter 900. One or more rings 930 may be disposed along a length of a distal portion of the catheter 900 and be configured to constrain a shape of the distal portion (e.g., distal end) of the catheter 0900. Activating the actuator (e.g., pushing the slider distal) may advance the wires 920 relative to the rings 930 to allow the distal end of the catheter 900 to bias to the treatment (e.g., expanded) configuration, thereby forming a funnel shape at the distal tip portion of the catheter 900. In some embodiments, a distal portion of the catheter 900 may comprise a durometer of between about 20 Shore A and about 40 Shore A. For example, the catheter 900 may comprise a polymer. In some embodiments, a distal portion of the catheter 900 may comprise a self-expanding structure (e.g., nitinol stent).

[0163] In some embodiments, the distal tip portion may be configured to transition between a delivery configuration (e.g., linear configuration) and a treatment configuration (e.g., nonlinear configuration, shaped section) having a predetermined (e.g., pre-formed, pre-shaped) bias. For example, the distal tip portion 910 may be constrained within one or more of a delivery catheter, a guidewire, and a perforating wire, and the distal tip portion 910 may be configured to expand when advanced distal to the delivery catheter such as when disposed within an SDH. In another example, the distal tip portion 910 may be configured to transition between a delivery configuration having a linear shape when a coaxial wire is disposed within a lumen of the catheter 900 and an expanded configuration (e.g., having a 3D shape) when the wire is removed from the lumen and the catheter 900 is unconstrained in a subdural space.

[0164] In some embodiments, the catheter 900 may be advanced in a delivery configuration (e.g., linear configuration) over a guidewire to a perforation point inside the MMA. Then, the perforation element may be advanced into the vascular lumen via the catheter 900 and actuated to create an opening in the vessel wall to provide access to the subdural space and to occlude the vessel to prevent fluid from entering the intracranial space or refluxing into the vessel. The catheter 900 may then be advanced over the perforation element into the subdural space in the delivery configuration. The perforation element may be withdrawn and thecatheter 900 inside the subdural space may transition to the expanded configuration (e.g., having the 3D shape), thereby confirming its location within the subdural space. In some embodiments, fluoroscopic visualization may confirm the expanded configuration of the catheter 900 within the subdural space. These features may improve navigation and drainage. For example, during intravascular advancement or when positioned intra or epidurally, the catheter 900 may not be constrained by the vessel wall and dura and may therefore maintain a linear configuration. Withdrawal of the wire coupled with the catheter maintaining the linear configuration corresponds to the catheter 900 positioned outside the subdural space.Moreover, the expanded configuration (e.g., 3D shape) of the catheter 900 combined with the plurality of apertures may improve drainage of fluid. For example, for a catheter having a 3D spiral shape in the expanded configuration, subdural fluid may be drained by most if not all of the apertures. Drainage of fluid will result in a reduction in volume of the SDH with a corresponding movement of the brain toward the inner dura, which will eventually lead to occlusion of the apertures of the catheter facing tissue, but with patency of inward facing apertures.

[0165] In some embodiments, the distal tip portion may comprise one or more of a braid, coil, wire, may be heat-biased, and / or mechanically actuated (e.g., via pull wires). For example, pull wires may be configured to articulate, deflect and / or steer the catheter.

[0166] In some embodiments, a distal tip portion of a catheter may be configured to form a predetermined three-dimensional shape inside a sack of an SDH between the brain and the dura to facilitate aspiration of the SDH and reduce clogging. Depending on the geometry (e.g., volume, shape) of the subdural hematoma, a distal tip portion can be selected to fill or substantially fill the volume of the SDH. With respect to FIGS. 10A-13B, fluid from an SDH may be drained more efficiently and completely when apertures of a catheter are minimally occluded by a membrane of the SDH sack.

[0167] FIG. 10A is a schematic side view of a catheter 1000 having a distal tip portion 1010 and a plurality of apertures 1020. The distal tip portion 1010 may generally have a pigtail shape that may curl around 360 degrees. FIG. 10B is a schematic side view of a catheter 1002 having a distal tip portion 1010 and a plurality of apertures 1020. The distal tip portion 1010 may generally have a spiral shape which may include one or more spirals. FIG. 10C is a schematic side view and corresponding front view of a catheter 1004 having a distaltip portion 1010 and a plurality of apertures 1020. The distal tip portion 1010 may generally have a plurality of angular bends (e.g., joints) along a length of the catheter 1004. For example, a first bend may be formed along a first plane (e.g., X-plane) and a second bend may be formed along a second plane (e.g., Y-plane) perpendicular to the first plane. In some embodiments, the apertures 1020 located at or adjacent to an apex of a curvature may have a slit shape in order to increase an area of the aperture and to facilitate shaping of the catheter curvature in a treatment (e.g., non-linear, expanded) configuration.

[0168] In some embodiments, a length of the distal tip portion may be between about 1 cm and about 10 cm, between about 1 cm and about 5 cm, between about 5 cm and about 10 cm, and between about 3 cm and about 7 cm, inclusive of all ranges and subranges therebetween. In some embodiments, a diameter of the distal tip portion of the catheter may be between about 0.010 inches and about 0.055 inches, between about 0.020 inches and about 0.055 inches, between about 0.010 inches and about 0.030 inches, and between about 0.020 inches and about 0.055 inches, inclusive of all ranges and subranges therebetween.

[0169] FIG. 10D are schematic lateral views of respective catheters 1000, 1002, 1004 in a head of a subject. For example, each of catheters 1000, 1002, 1004 are in a treatment configuration where the catheters 1000, 1002, 1004 are unconstrained and disposed within a respective SDH 1030, 1040, 1050. As SDH fluid is suctioned through the catheters 1000, 1002, 1004, the volume of the SDH decreases such that the membranes forming the outer perimeter (e.g., sack) of the SDH 1030, 1040, 1050 surround and contact the catheters 1000, 1002, 1004. Due to the three-dimensional shapes and volumes provided by the catheters 1000, 1002, 1004 in the treatment configuration, the catheters 1000, 1002, 1004 may continue to suction the SDH fluids even as the membrane of the SDH 1030, 1040, 1050 occludes a portion of the plurality of apertures 1020 of the catheters 1000, 1002, 1004. In some embodiments, one or more shaped segments of the catheter (e.g., a portion of the catheter configured to bend, deform, or flex) may include one or more fiducials (e.g., indicators). In some embodiments, one or more shaped segments may include one or more radiopaque markers visible under fluoroscopy such as, for example, radiopaque fillers disposed in and / or integrated into a material (e.g., polymer) of the catheter 1000, 1002, 1004 used in construction; radio-fluorescent metals for a braid, coil or hybrid reinforcement structure; and / or radiopaque marker bands embedded in a wall of the catheter shaft and / or outside the catheter shaft.

[0170] FIG. 11 A is a schematic side view of a catheter 1100 including a plurality of apertures 1110, a suction lumen 1112 (e.g., drainage lumen), one or more expandable members 1120 (e.g., balloons), and an optional inflation lumen 1122. The plurality of apertures 1110 and expandable members 1120 may be disposed at a distal portion of the catheter. The plurality of apertures 1110 may be fluidically coupled to the suction lumen 1112 extending along a length of the catheter 1100. In some embodiments, one or more expandable members 1120 may be disposed distal and / or proximal to the plurality of apertures 1110. One or more expandable members 1120 may be configured to reduce obstruction (e.g., occlusion) of the apertures 1110. The inflation lumen 1122 may be fluidically coupled to the one or more expandable members 1120, and the inflation lumen 1122 may be configured to inflate the one or more expandable members 1120.

[0171] FIGS. 1 IB and 11C are schematic side views of a catheter 1102 including a plurality of apertures 1110, a suction lumen 1112, one or more expandable members 1130, and optionally one or more pull wires 1140. In some embodiments, the expandable member 1130 may comprise a frame (e.g., metal) or stent that may be configured to self-expand or be mechanically actuated between a delivery configuration (e.g., unexpanded, compact) and a treatment configuration (e.g., expanded). The expandable member 1130 may comprise one or more rings 1132 coupling the frame or stent to the catheter 1102. For example, the rings 1132 may include a distal ring and a proximal ring, and the expandable member 1130 and plurality of apertures 1110 may be coupled between them. The pull wires 1140 may be configured to transition the expandable member 1130 between a delivery configuration shown in FIG. 1 IB and a treatment configuration shown in FIG. 11C. The expandable member 1130 may be configured to center the catheter 1102 within a fluid cavity (e.g., SDH sac) to prevent particulate matter from occluding (e.g., clogging) the catheter 1102, thereby allowing the fluid to be drained via the apertures 1110.

[0172] In some embodiments, one or more of the rings 1132 may be configured to move relative to (e.g., along a length of) the catheter 1102 when actuated by the pull wires 1140 to transition between the delivery configuration and the treatment configuration. For example, a distal ring 1132 may be pulled proximally to transition the frame 1110 to the treatment configuration. In the treatment configuration, a membrane of an SDH sack may contact the expandable member 1120, 1130 to reduce occlusion of the apertures 1110, thus increasing efficiency of SDH removal. For a self-expanding frame 1130, the expandable member 1130may be in the delivery configuration when a catheter (e.g., perforation wire, guidewire) is disposed in the suction lumen 1112 and may transition to the treatment configuration when unconstrained.

[0173] FIGS. 12A-12C are schematic side views of catheters 1200, 1202, 1204 each including a plurality of apertures 1210, a suction lumen 1212 (e.g., drainage lumen), and one or more protrusions 1210 disposed on a surface of the catheter 1200, 1202, 1204 and configured to provide a barrier to reduce occlusion of the apertures 1210 during suction. The protrusions 1210 may be adjacent to one or more of the apertures 1210. The protrusions 1210 may be atraumatic and include one or more bumps, ridges, ribs, indentations, and the like. For example, the protrusions 1220 in FIG. 12B may be configured in an array pattern such that the protrusions 1220 are disposed between each aperture 1210. As shown in FIG. 12A, the protrusions 1220 may be disposed circumferentially about the catheter 1200. In FIG. 12C, the protrusions 1220 may be disposed parallel to a longitudinal axis of the catheter 1204 between rows of apertures 1210. In some embodiments, the protrusions may have a dimension between about 10% and about 200% larger than the diameter of the catheter. One or more protrusions 1210 may be configured to reduce obstruction (e.g., occlusion) of the apertures 1210.

[0174] FIGS. 13A and 13B are schematic side views of a catheter 1300 including a plurality of apertures 1310 (e.g., slits, slots) extending along a longitudinal axis of the catheter, a suction lumen 1312 (e.g., drainage lumen), and optionally one or more pull wires 1330. As shown in FIG. 13 A, the apertures 1310 may be circumferentially and / or longitudinal parallel to each other with respect to the longitudinal axis of the catheter 1300. In some embodiments, the catheter 1300 may be configured to self-expand or be mechanically actuated between a delivery configuration (e.g., unexpanded, compact) and a treatment configuration (e.g., expanded) where a diameter of the catheter 1300 increases corresponding to a location of the apertures 1310. The apertures 1310 in the treatment configuration may be configured to facilitate suction of fluid (e.g., an SDH). For example, the pull wires 1330 may be configured to transition the plurality of apertures 1310 between a delivery configuration shown in FIG. 13A and a treatment configuration shown in FIG. 13B. The pull wires 1330 may be coupled to an actuator (e.g., slider) disposed within a handle. One or more pull wires 1330 may extend through a length of the catheter 1300. Activating the actuator (e.g., retracting the slider proximal) may retract the wires relative to the catheter 1300 to allow thedistal end of the catheter to bias to the expanded configuration, thereby increasing a size of the apertures 1310.

[0175] In some embodiments, a distal portion of the catheter 1300 comprising the apertures 1310 may have a predetermined (e.g., pre-formed, pre-shaped) bias. For example, the catheter 1300 may comprise shaped metal strips between the apertures 1310 configured to bias (e.g., bow) outward when unconstrained.

[0176] In some embodiments, a guidewire disposed within a lumen 1312 of the catheter 1300 may be configured to provide tension that maintains the catheter 1300 in the delivery configuration. Withdrawal of the guidewire from the lumen 1312 of the catheter 1300 may relieve the tension in the catheter 1300 and facilitate radial expansion of the catheter 1300 to transition the catheter 1300 into the treatment configuration. In some embodiments, a perforation element may be configured to control tension of the catheter 1300.

[0177] Additionally or alternatively, a distal portion of the catheter 1300 including the plurality of apertures 1310 may be constrained within a delivery catheter (not shown) and configured to expand when advanced distal to the delivery catheter. The apertures 1310 may have the same or different length and width. The location and number of apertures 1310 is not particularly limited. For example, the plurality of apertures 1310 may include a first set of apertures 1314 at a distal end of the catheter 1300 and a second set of apertures 1316 proximal to the first set of apertures 1314. In some embodiments, a mesh (e.g., filter) may be coupled to the apertures 1310 (e.g., within a catheter wall, over the catheter) and configured to allow fluid to enter the catheter lumen during aspiration and prevent particulate matter having a predetermined size (e.g., clots, brain tissue, membranes, septations) from entering the lumen 1312, thereby preventing occlusions.

[0178] In some embodiments, a catheter assembly (e.g., apparatus) may comprise a catheter (e.g., elongate body) defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel, and the lumen including a distal curve. An opening may be disposed on the distal end of the elongate body, the opening being in communication with the lumen. The elongate body may be configured to be steerable to a location in the intracranial vessel. The elongate body may be further configured to receive a perforating device through the lumen such that the perforating device can be guided via the distal curve and out through the opening toward a wall of the intracranial vessel to perforatethe wall and form a passageway into the intracranial extravascular space. For example, FIG. 14A is a schematic cross-sectional side view of a catheter assembly 1400 including a catheter 1410 and a perforating device (e.g., shaft) 1420 disposed therein. The catheter 1410 may comprise a lumen 1412 therethrough coupled to a distal opening 1414 (e.g., window) along a sidewall of the catheter 1410. A distal end of the perforating device 1420 may comprise a perforating element 1422 and be configured to advance through the lumen 1412 and out of the distal opening 1414. The lumen 1412 may include a distal curve 1416 (e.g., ramp, lateral deflector) configured to guide (e.g., deflect) the perforating device 1420 or perforating element medially, laterally, or any angle thereof in between. In some embodiments, the ramp or lateral deflector can direct the shaft or perforating element at an angle a between about 5 degrees and about 90 degrees, from a plane perpendicular to a longitudinal axis of the catheter device, smoothly out of the distal opening 1414. In some embodiments, the catheter 1410 may further comprise one or more fiducials 1418 (e.g., radiopaque markers) configured to aid positioning of the catheter 510 within the vessel 1440. For example, a distal portion of the catheter 1410 may include a first fiducial distal to the distal opening 1414 and a second fiducial proximal to the distal opening 1414. The position of the fiducials 518 relative to each other may indicate, for example, the location of the distal opening 1414 within the body (e.g., within the MMA). In some embodiments, the perforating element 1422 may comprise a fiducial (e.g., radiopaque marker) configured to facilitate orientation of the perforating element 1422 relative to subject anatomy. In some embodiments, the fiducial may comprise a shape including one or more of a linear shape, T-shape, I-shape, J-shape, U-shape, C-shape, V-shape, an M-shape, an S-shape, a helix, a spiral, a coil, and combinations thereof. For example, visualization of the perforating element 1422 may confirm that the perforating element 1422 is directed toward the dura 1450 and SDH 1460 rather than bone 1430.

[0179] FIG. 14B is a schematic cross-sectional side view of a catheter assembly 1400 disposed within a head of a subject including a skull 1430, a vessel 1440 (e.g., MMA), a dura 1450, an SDH 1460, and brain 1470. For example, the catheter 1410 may be disposed within the vessel 1440 and the perforating device 1420 may be configured to penetrate the vessel wall 1440, the dura 1450, and the SDH 1460. In some embodiments, the distal curve 1416 and distal opening 1414 may be configured to direct the perforating device 1420 toward predetermined anatomy such as a vessel wall 1440 and / or dura 1450.

[0180] FIG. 43A depicts a catheter assembly 4300 including an inflatable (i.e., expandable) lumen and / or a balloon element 4350 at or near a distal opening of the catheter. The expandable member (e.g., balloon) 4350 may be configured to inflate or expand to a predetermined diameter (e.g., corresponding to a diameter of a vessel 4310). For example, the expandable member 4350 may be configured to transition between a delivery configuration and an expanded configuration. In some embodiments, the expandable member 4350 can be configured to inflate to a diameter between about 20 mm and about 80 mm, inclusive of all ranges and subranges therebetween. The expandable member 4350 in an expanded configuration as shown in 4301, 4302 can form any suitable shape such as, for example, a round shape, a flat shape, or an oblong shape. In 4302, a perforating element 4360 may be advanced out of an aperture of the assembly 4300. In some embodiments, the expandable member 4350 when inflated can at least partially fill the vessel 4310 and compress against (i.e., press against, abut, etc.) the dura 4320 and bone 4330, thereby securing (e.g., anchoring) the catheter 4300 in a position for perforation and occluding the vessel, thereby preventing fluid from entering the intracranial space or refluxing into the vessel.

[0181] In some embodiments, the expandable member 4350 having a flat or oblong shape can expand in a two-dimensional direction such that the expandable member 4350 forms a substantially flat geometry or low-profile geometry. The substantially flat geometry can orient an opening defined in a distal end of the catheter 4300 to face toward the dura 4320 and / or subdural space, using the skull bone 4330 as a backstop (i.e., a surface for the expandable member 4350 to conform to or press against) as the expandable member 4350 expands outward. In some embodiments, the opening of the catheter 4300 may face toward the bone 4330 when the expandable member 4350 expands outward. In some embodiments, a perforating element 4360 of a perforating device can be used to determine if the distal opening is oriented toward the subdural space or toward the bone 4330. In some embodiments, the perforating element 4360 may include an indicator and / or marker (e.g., a radiopaque marker at a tip of the catheter 4300), and when the marker of the perforating element 4360 is inserted through the catheter 4300, the marker can be visible to the user under visualization and indicate to the user whether a distal end of the perforating element 4360 is tracking toward the subdural space or toward the skull bone 4330.

[0182] FIG. 43B shows a catheter assembly 4300 including an expandable member 4350 including one or more electrode(s) 4340 disposed thereon. The expandable member 4350 inan expanded configuration is shown in 4304. A side view of the expandable member 4350 in the expanded configuration is shown in 4305. The side view of 4306 illustrates the catheter assembly 4300 in a vessel (e.g., MMA) between the skull bone 4330 and the dura 4320. In some embodiments, one or more electrodes 4340 may be disposed along a center line (e.g., longitudinal axis) of the catheter 4300 and / or otherwise disposed (e.g., skewed) such that the electrodes 4340 can contact the vessel wall and / or dura 4320. In some embodiments, the electrodes 4340 can be connected (e.g., electrically connected) via lead (e.g., supply wire) 4310. The lead 4310 may be configured to extend along a length of the catheter 4350 to a proximal connector (not shown for the sake of clarity). In some embodiments, the proximal connector may be configured to connect to a power source (e.g., a radiofrequency generator). For example, the power source may be configured to activate the electrode 4340 via the lead 4310. When activated, the electrodes 4340 may be configured to vaporize the tissue, thereby creating a passageway in the subdural space to enable a perforating element 4360, guide wire, microcatheter, hemostatic device, etc. to access the subdural space.

[0183] In some embodiments, a catheter can be configured to improve drainage (e.g., suction) of fluid including an SDH. FIG. 15A is a schematic cross-sectional side view of a catheter 1500 including a first catheter 1510 coupled proximal to a second catheter 1520. The first catheter 1510 may include a first lumen 1512 and the second catheter 1520 may include a second lumen 1522. In some embodiments, the second catheter 1520 may be fit into the first catheter 1510 where an inner diameter of the first catheter 1510 is substantially equal to an outer diameter of the second catheter 1520, thereby facilitating relative motion between the first catheter 1510 and the second catheter 1520 as well as a fluid-tight seal. In some embodiments, an outer diameter of a proximal portion of the second catheter 1520 may be between about 0.00025 inches and about 0.005 inches smaller than an inner diameter of a distal end of the first catheter 1510 to form an airtight seal. When the first catheter 1510 and the second catheter 1520 are coupled via friction fit, negative pressure applied through the first catheter 1510 may propagate through the second catheter 1520 and facilitate drainage of a SDH.

[0184] In some embodiments, that first catheter 1510 has a first length and the second catheter 1520 has a second length less than the first length. Accordingly, an inner diameter of the catheter assembly may increase proximally. For example, a first catheter may have a length of between about 110 cm and about 140 cm, a first distal inner diameter of betweenabout 0.040 inches and about 0.055 inches, and a second catheter may have a length of between about 10 cm and about 25 cm, and a second inner diameter of between about 0.016 inches and about 0.030 inches.

[0185] In some embodiments, the second catheter 1520 may be coupled to a proximal segment 1530 (e.g., push wire, pull wire) configured to extend proximally. In some embodiments, the proximal segment may be configured for navigation. For example, the proximal segment may be configured to control translation (e.g., longitudinal bidirectional movement, push, pull) of the second catheter 1520 through a vessel. In some embodiments, the proximal segment 1530 may be absent a lumen to aid pushability. For example, the proximal segment 1530 may comprise one or more of a hypotube, a single solid rod, a wire (e.g., with one of more cross-sectional shapes including round, flat, square, diamond), a plurality of rods, a bundle, one or more tubes (with one or more lumens), a plurality of shaft strands, a cable (e.g., two or more wires running side by side, bonded, twisted or braided), a coil, a braid, a wire (e.g., round, flat, square, diamond), combinations thereof, and the like. The second lumen 1522 may be configured to receive one or more of a shaft, negative pressure, SDH, hemostatic device, combinations thereof, and the like. The proximal segment may have a smaller diameter than the second catheter 1520.

[0186] In some embodiments, the proximal segment 1530 may comprise one or more of stainless steel, nitinol, nitinol alloy, combinations thereof, and the like. The proximal segment 1530 may comprise one or more of a round cross-section having an outer diameter of between about 0.010 inches and about 0.030 inches, a flat wire cross-section having a width of between about 0.008 inches and about 0.020 inches, and a length of between about 0.012 inches and about 0.030 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the proximal segment 1530 may comprise a connecting portion configured to connect to a proximal wall of the catheter. For example, the connecting portion may comprise a flatted portion (where the proximal segment otherwise has a round cross-section) having a length of between about 3 mm and about 3 cm, inclusive of all ranges and subranges therebetween.

[0187] In some embodiments, a proximal end 1532 of the proximal segment 1530 may comprise a handle 1532 (e.g., hook, eyelet, grip) configured to be grasped and manipulated by an operator. For example, the proximal segment 1530 may be translated relative to thefirst catheter 1510 to insert or withdraw the second catheter 1520 within the first catheter 1510. The proximal segment 1530 may be coupled directly or indirectly to a sidewall of a proximal portion of the second catheter 1522. FIGS. 15B-15F are schematic detailed cross- sectional side views of exemplary proximal segments 1530, 1532. For example, FIG. 15B depicts a wire 1530 coupled to a ring 1540 (e.g., radiopaque ring) configured to couple to an inner diameter of the second catheter 1520. FIG. 15C depicts a wire 1530 coupled to a braid 1542, FIG. 15D depicts a wire 1530 coupled to a coil 1544, and FIG. 15F depicts a wire 1530 coupled to a reinforcement 1546. As shown in FIG. 15E, a distal portion of a wire 1532 may comprise a coil shape 1532.

[0188] FIG. 16A is schematic cross-sectional side view of a catheter configured for electromagnetic navigation. For example, a catheter 1600 may include a lumen 1602, a sidewall 1610, a closed loop return wire 1620, an insulator 1630, a coiled wire 1640, and a plurality of magnets 1650. FIG. 16B is a schematic cross-sectional front view of the catheter 1600 depicting the plurality of magnets 1650 disposed circumferentially within the sidewall 1610 with the coiled wire 1640 and insulator 1630 disposed circumferentially around the plurality of magnets 1650. In some embodiments, one or more of the plurality of magnets 1650 may extend along a predetermined length of the catheter 1600 such that the steerable portions of the catheter 1600 correspond to those portions including magnets 1650. In some embodiments, each magnet of the plurality of magnets 1650 may have an atraumatic shape (e.g., rounded ends) to facilitate coupling with an adjacent magnet and provide flexibility (e.g., flexing, bending, swiveling, etc.) to the catheter 1600. In some embodiments, the magnet 1650 may have a diameter of between about 0.005 inches and about 0.007 inches, between about 0.005 inches and about 0.006 inches, and between about 0.006 inches and about 0.007 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the magnet 1650 may have a length of between about 0.5 mm and about 5 mm, between about 0.5 mm and about 4 mm, between about 0.5 mm and about 3 mm, between about 0.5 mm and about 2 mm, between about 0.5 mm and about 1 mm between about 1 mm and about 5 mm between about 2 mm and about 5 mm, between about 3 mm and about 5 mm, and between about 4 mm and about 5 mm, inclusive of all ranges and subranges therebetween.

[0189] In some embodiments, a coiled wire 1640 may be coupled to each magnet 1650. For example, as shown in FIG. 16B, the coiled wire 1640 may surround the plurality of magnets1650. In some embodiments, the coiled wire 1640 may be a closed loop conductive wire comprising one or more of copper, brass, aluminum, stainless steel, combinations thereof, and the like. In some embodiments, the plurality of magnets 1650 and coiled wire 1640 may be disposed within the insulator 1630 such as a polymer. The coiled wire 1640 may be configured to electrically couple to a closed loop return wire 1620 that extends to a proximal portion of the catheter 1600 (e.g., to a handle). For example, the closed loop return wire 1620 may be disposed on an outer surface of the insulator 1630.

[0190] In some embodiments, an electromagnetic field generated by current applied to the coiled wire 1640 may be used to navigate (e.g., steer, bend, articulate) the catheter 1600 through a body. A change in current density and / or coil pitch and / or length of the magnets may modify the electromagnetic field, thereby changing a degree of articulation. For example, a change in current direction will change the direction of the articulation, thereby providing a steerable catheter. In some embodiments, one or more of external magnetic conductors (e.g., disposed external to the body) and Magnetic Resonance Imagining (MRI) may be used to navigate the catheter 1600 using magnetic gradients to control deflections. For example, a head-mounted device (e.g., helmet) may comprise a plurality of spaced apart magnetic conductors configured to generate a magnetic field for steering a catheter 1600 disposed in the head.

[0191] In some embodiments, a hardness (e.g., durometer) of the catheter 510 (e.g., elongate body) may vary along a length of the catheter 510 from between about 40 Shore A and about 100 Shore A, between about 20 Shore D and about 100 Shore D, and between about 50 Rockwell R and about 120 Rockwell R to provide flexibility in predetermined portions of the catheter 510. For example, a hardness of a proximal portion 513 may be greater than a hardness of a distal portion 512 thereby facilitating navigation of tortuous vessels at a distal portion of the catheter 510 while providing pushability with a relatively stiff proximal portion 512.

[0192] In some embodiments, a catheter assembly 2600 may comprise a multi-lumen catheter 2610 having a perforating device (e.g., shaft) 2620 and guidewire 2630 disposed therein. For example, FIGS. 26A, 26B, and 26E are schematic cross-sectional side views of a catheter assembly 2600 including a catheter 2610 having a first lumen 2612 and a second lumen 2614. A perforating device (e.g., shaft) 2620 may be disposed within the first lumen2612 and a guidewire 2630 may be disposed within the second lumen 2614. In some embodiments, an actuator 2640 may be coupled to a proximal end of the perforating device 2620 and configured to translate the perforating device 2620 relative to the catheter 2610. For example, the actuator 2640 may include a locking mechanism. The perforating device 2620 may be one or more of a flexible needle and a hypodermic tube defining a lumen 2622. The first lumen 2612 may be configured to receive the perforating device 2620 and negative pressure to suction fluid (e.g., SDH). The second lumen 2614 may be configured to receive the guidewire 2630 for navigation through vasculature. In some embodiments, a distal portion of the catheter 2610 may include a ramp 2615 configured to direct the perforating device 2620 through opening 2613 at a predetermined angle relative to a longitudinal axis of the catheter 2610. The opening 2713 may be disposed along one or more of a sidewall and a distal end of the catheter 2610. For example, as shown in FIG. 26E, the ramp 2615 and opening 2613 may facilitate advancement of a perforating device 2620 out of the catheter 2610 at an oblique angle when the actuator 2640 is advanced in a distal direction. In some embodiments, the sidewalls of the perforating device 2620 may comprise one or more cut patterns (e.g., slots, slits, cuts, and spirals) configured to increase flexibility and promote deflection of the perforating device 2620 relative to the ramp 2615. For example, a higher number and / or density of slots, slits, cuts, spirals, etc. along a first side of the perforating device 2620 will increase flexibility relative to a second side opposite the first side having a relatively fewer number and / or density of slots, slits, cuts, spirals, etc. FIG. 26C is a schematic cross-sectional front view of the catheter 2610 depicting the first lumen 2612 and the second lumen 2614. FIG. 26D is a schematic cross-sectional perspective view of the catheter 2610 showing the first lumen 2612, second lumen 2614, and opening 2613.

[0193] FIGS. 26F and 26G are schematic cross-sectional side views 2650, 2660 of a catheter assembly in a head of a subject. In some embodiments, the catheter 2610 may comprise a first fiducial 2616 distal to the opening 2613 and a second fiducial 2618 proximal to the opening 2613. For example, the first fiducial 2616 may comprise a T-shape or I-shape disposed along a sidewall of the catheter 2610 opposite the opening 2613 in order to provide visual confirmation that the opening 2613 faces a predetermined access site (e.g., perforation point in the vessel wall). In step 2650, a guidewire 2630 may be advanced into a vessel 2680 through a second lumen 2614 of the catheter 2610. For example, the guidewire 2630 may be advanced into a side branch of the MMA to orient the catheter device along a two-dimensional plane between the bone 2670 (e.g., skull) and dura 2690, thereby allowing a perforating device 2620 to orient obliquely or perpendicularly to the dura 2690 and directing a perforating element of the perforating device 2620 towards a SDH 2695. FIG. 26G depicts in step 2660 the perforating device 2620 obliquely perforating the vessel wall 2680, the dura 2690, and SDH 2695.

[0194] In some embodiments, the catheter 2610 may comprise a single lumen configured to receive each of the perforating device 2620 and guidewire 2630. For example, a guidewire 2630 may be advanced through the first lumen 2612 and into predetermined vasculature. The catheter 2610 may be advanced over the guidewire 2630, and then the guidewire 2630 may be retracted. The perforating device 2620 may be advanced through the first lumen 2612 and through the opening 2613 to perforate one or more of the vessel wall 2680, dura 2690, and SDH 2695. The guidewire 2630 may be advanced through the lumen 2622 of the perforating device 2620 and into the subdural compartment for facilitating navigation of an aspiration catheter.Catheter and Shaft Coupling

[0195] In some embodiments, a catheter assembly (e.g., apparatus) may include a catheter (e.g., elongate body) and a perforating device (e.g., shaft) each having corresponding portions of a coupling mechanism configured to releasably couple the catheter to the perforating device. For example, the perforating device may include a perforation element configured to be used co-axially with a catheter including a proximal push wire and a distal tubular portion. Mechanically coupling the catheter to the perforating device facilitates forward force transmission (e.g., pushability for transvascular access and advancement through small vessels such as those in head and the perforation site), which may be particularly beneficial when the catheter is designed with thin sidewalls (e.g., to maximize an inner lumen diameter) and / or proximally coupled to a low-profile push wire that may be intentionally small to maximize a cross-sectional luminal area in the catheter assembly despite suboptimal pushability and stiffness.

[0196] In an exemplary method of transvascular drainage of subdural hematoma, the MMA may be embolized and a delivery catheter may be advanced into the extracranial MMA. Then, a distal tubular portion of a catheter may be introduced inside a sheath (e.g., delivery catheter) using, for example, a hemostatic rotational valve. The sheath and catheter may beco-axially advanced over a guidewire into the MMA by pushing the push wire of the catheter. The guidewire may then be removed from the catheter assembly, and the perforating device may be introduced inside the sheath, parallel to the push wire of the catheter. The perforating device may be advanced distally until it enters the lumen of the tubular portion of the catheter and extends distal to a distal end of the catheter. The perforating device may be further advanced to the perforation point in the lumen of the MMA, and then actuated to create an opening to provide transvascular access to the subdural space. The perforating device may be further advanced in the subdural space (e.g., between about 1 cm and about 5 cm) such that the perforating device mechanically couples with the tubular portion of the catheter. After coupling, the catheter’s push wire and the perforating device may be advanced together, thereby resulting in transvascular advancement of the catheter into the subdural space with maximum force transmission. The perforating device may then be withdrawn from the catheter assembly, and the telescoping catheter assembly formed by the sheath (located proximally of the distal end of the catheter) and the distal tubular catheter (still coupled to a push wire) may be connected to a vacuum source to drain the subdural collection (e.g., hematoma). After draining the subdural hematoma, the distal tubular portion of the catheter may be withdrawn into the vascular lumen by pulling on the pull wire. The arteriotomy may thereafter be closed.

[0197] In some embodiments, the coupling mechanism can be single or multiple, and be disposed in any of the proximal end of a tubular portion of the catheter, along the length of the tubular portion of the catheter, or at a distal end of a tubular portion of the catheter.

[0198] In some embodiments, a proximal portion of the perforating device may have an outer diameter that substantially matches an inner diameter of a distal portion of a catheter such that the perforating device may be coupled to the catheter via a friction fit. In some embodiments, the perforating device includes a proximal portion having an outer diameter that tapers from a first outer diameter substantially equal to an inner diameter of the catheter to a second outer diameter, such that the proximal portion is configured to restrict a length that the perforating device can advance distally beyond the distal end of the catheter. In some embodiments, an inner diameter of a distal end of a catheter may decrease or narrow gradually and / or in step-wise increments. Accordingly, a perforating device may be advanced through a catheter until a proximal portion of the perforating device abuts a distal portion ofthe catheter where the inner diameter of the catheter substantially matches the outer diameter of the perforating device.

[0199] In some embodiments, a catheter assembly (e.g., apparatus) may comprise an elongate body defining a lumen, the elongate body including a proximal end having a first coupling portion and a distal end configured to be disposed in an intracranial vessel. A perforating device may include a second coupling portion where the perforating device may be configured to be advanced through the lumen of the elongate body until the second coupling portion of the perforating device engages with the first coupling portion of the elongate body. The perforating device, when advanced such that the first and second coupling portions are engaged, may further be configured to perforate through a wall of the intracranial vessel to form a passageway into the intracranial extravascular space. FIGS. 18A-18D are schematic cross-sectional side views of respective catheter assemblies 1800, 1802, 1804, 1806. In some embodiments, the catheter assembly may include a coupling mechanism where the catheter includes a first coupling portion and the perforating device (e.g., shaft) includes a second coupling portion configured to couple (e.g., mate, interlock, secure, hold) to the first coupling portion. For example, the catheter assembly 1800 of FIG. 18A includes a catheter 1810 releasably coupled to a perforating device (e.g., shaft) 1820. The catheter 1810 may include a first coupling portion 1812 and a push wire 1814 coupled to a proximal portion of the catheter 1810. The wire 1814 may be configured to distally advance the catheter 1810 (e.g., elongate body). The perforating device 1820 may be configured to be disposed within a lumen of the catheter 1800 and includes a second coupling portion 1822 configured to mate with the first coupling portion 1812 via an interference fit. The catheter assemblies 1800, 1802, 1804, 1806 differ in the geometry of their respective second coupling portions 1822, 1824, 1826, 1828. For example, the second coupling portion 1822 may have a tapered (e.g., conical, parabolic, ground segment) shape such that a diameter of the second coupling portion 1822 increases beyond an inner diameter of the first catheter 1810. The perforating device 1820 of FIG. 18B has a second coupling portion 1822 having a step with an outer diameter larger than an inner diameter of a lumen of the catheter 1810 such that translation of the perforating device 1820 through the catheter 1810 is limited to a predetermined range. In some embodiments, as shown in FIG. 18C, the second coupling portion 1826 may include a plurality of tapered portions to provide flexibility for catheters 1810 having various inner diameters. The perforating device 1820 of FIG. 18D has a second coupling portion 1828having a tapered (e.g., conical, parabolic) shape and a first coupling portion 1812 has a corresponding tapered shape configured to receive the second coupling portion 1828. Although depicted in FIGS. 18A-18D at a proximal end of the catheter 1810, the first coupling portion 1812 may be disposed along any portion of the catheter 1810, such as at a distal end of the catheter as described with respect to FIGS. 20A and 20B.

[0200] FIGS. 44A-44C are schematic cross-sectional side views of respective catheter assemblies 4400, 4500, 4600. In some embodiments, the catheter assemblies 4400, 4500, 4600 may respectively include a coupling mechanism including a tapered inner lumen catheter including a first coupling portion 4412, 4512, 4612 and a perforating device (e.g., shaft) 4420, 4520, 4620 including a second coupling portion 4422, 4522, 4622 configured to be coupled (e.g., mate, interlock, secure, hold) to the first coupling portion 4412, 4512, 4612. For example, the catheter assembly 4400 of FIG. 44 A includes a catheter 4410 releasably coupled to a perforating device 4420. The catheter 4410 may include a first coupling portion 4412. The perforating device 4420 may be configured to be disposed within a lumen of the catheter 4400 and includes a second coupling portion 4422 configured to mate with the first coupling portion 4412 via an interference fit. The catheter assemblies 4400, 4500, 4600 can differ in the geometry of the second coupling portions 4422, 4522, 4622. For example, the second coupling portion 4422 may have a tapered (e.g., conical, parabolic, ground segment) shape such that an outer diameter of the second coupling portion 4422 increases beyond (e.g., is larger than) an inner diameter of the first coupling portion 4412 of the first catheter 4410. The perforating device 4520 of FIG. 44B can include a second coupling portion 4522 including a step with an outer diameter larger than an inner diameter of a lumen of the catheter 4510 at the first coupling portion 4612 such that translation of the perforating device 4520 through the catheter 4510 is limited to a predetermined range. In some embodiments, as shown in FIG. 44C, the second coupling portion 4622 may include a plurality of tapered portions 4624, 4626 to provide flexibility for catheters 4610 having various inner diameters. Although depicted in FIGS. 44A-44C near a proximal end of the catheter 4410, 4510, 4610, the first coupling portion 4412, 4520, 4620 may be disposed along any portion of the catheter 4410, 4510, 4610, such as at a distal end of the catheter 4410, 4510, 4610, as described with respect to FIGS. 20 A and 20B.

[0201] FIGS. 19A-19D are schematic cross-sectional side views of respective catheter assemblies 1900, 1902, 1904, 1906. Similar to FIGS. 18A-18D, the catheter assembly 1900of FIG. 19A includes a catheter 1910 releasably coupled to a perforating device (e.g., shaft) 1920. The catheter 1900 may include a first coupling portion 1912 (e.g., detent, recess, groove). The perforating device 1920 may be configured to be disposed within a lumen of the catheter 1910 and includes a second coupling portion 1922 (e.g., protrusion, bump) configured to mate with the first coupling portion 1912 via a snap fit. The catheter assemblies 1900, 1902, 1904, 1906 differ in the geometry of their respective coupling portions 1912, 1922. For example, the coupling portions 1912, 1922 of catheter assembly 1900 may have rounded shapes, the coupling portions 1912, 1922 of catheter assembly 1902 may have a step (e.g., square) shape, and the coupling portions of catheter assemblies 1904, 1906 may have tapered (e.g., triangular inward, triangular outward) shapes. Additionally or alternatively, the first and second coupling portions 1912, 1922 may comprise one or more of male and female threads, and magnets. In some embodiments, the location of the coupling portions 1912, 1922 may determine a length that the perforating device 1920 may extend distal to a distal end of the catheter 1910. In some embodiments, friction between the first and second coupling portions 1912, 1922 may be modified based on surface features including one or more of roughness and hydrophobic coatings.

[0202] In some embodiments, a distal end of a catheter and a perforating device may have corresponding portions of a coupling mechanism configured to provide stiffness and strength to the distal end of the catheter when coupled to the perforating device in order to facilitate transvascular passage through a vessel wall and / or dura and into an extravascular intracranial space. FIGS. 20 A and 20B are schematic cross-sectional side views of catheter assemblies 2000, 2002. The catheter assembly 2000 of FIG. 20A includes a catheter 2010 releasably coupled to a perforating device (e.g., shaft) 2020. The catheter 2000 may include one or more fiducials 2030. The perforating device 2020 may be configured to be disposed within a lumen of the catheter 2010 and includes a coupling portion 2022 (e.g., protrusion, bump) configured to mate with a distal end of the catheter 2010 via an interference fit. For example, an inner diameter of a lumen at a distal end of the catheter 2010 may be substantially the same as an outer diameter of the coupling portion 2022 of the perforating device 2020. Occupying the inner lumen of the catheter 2010 with the coupling portion 2022 of the perforating device 2020 for a length of between about 0.5 cm and about 15.0 cm including all ranges and subvalues therebetween may increase the stiffness and strength of the catheter assembly 2000, 2002 to reduce deformation (e.g., ovalization of the catheter 2010) thereby facilitating theadvancement of the catheter 2010 through an opening. In some embodiments, the coupling portion 2022 of the perforating device 2020 may be configured to expand an opening (e.g., arteriotomy) and / or transvascular corridor. Expanding the opening using the coupling portion 2022 may further provide occlusion to prevent bleeding into and / or through the opening. Additionally or alternatively, an inner diameter of a lumen at a distal end of the catheter 2010 may be smaller relative to an inner diameter of the lumen at other portions of the catheter 2010 to improve coupling between the catheter 2010 and the coupling portion 2022 of the perforating device 2020. In this manner, a load may be transmitted distally from the perforating device 2020 to the catheter 2010. In some embodiments, coupling the catheter 2010 and the perforating device 2020 may elongate a distal portion of the catheter shaft thereby reducing the outer diameter up to 30% during force transmission allowing the catheter to slidably navigate through the opening (e.g., perforation) and into the intracranial space. The catheter 2010 will then return to the original outer diameter, relaxing the perforating device 2020, thereby allowing the perforating device 2020 to have increased fluid flow for drainage as well as occluding the perforated opening and vessel and preventing fluid to flow into the intracranial space or refluxing into the vessel.

[0203] In some embodiments, the coupling portion 2022 of the perforating device 2020 may include one or more fiducials 2032 where the fiducials 2030, 2032 facilitate alignment of the perforating device 2020 relative to the catheter 2010 via fluoroscopic visualization. For example, prior to perforation of tissue (e.g., vessel, dura), visualization of the catheter 2010 and perforating device 2020 may confirm that the coupling portion 2022 of the perforating device 2020 is coupled to and aligned with a distal end of the catheter 2010.

[0204] In some embodiments, a coupling mechanism of a catheter assembly may synergistically facilitate translation through vasculature and perforation of a vessel wall and / or dura by increasing stiffness and strength to the catheter assembly. FIG. 25A is a schematic cross-sectional side view of a catheter 2500 including a first portion 2502, a second portion 2504, a third portion 2506, and a lumen 2501 therethrough. The first portion 2502 may correspond to a distal portion of the catheter 2500 and comprise a plurality of apertures 2503 (e.g., disposed around a circumference of the first portion 2502). The first portion 2502 (e.g., distal portion) may have a length L3 and an inner diameter 02. In some embodiments, the inner diameter 02 of the first portion 2502 may be between about 0.018 inches and about 0.027 inches, between about 0.018 inches and about 0.023 inches, betweenabout 0.023 inches and about 0.027 inches, and between about 0.020 inches and about 0.025 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the length L3 of the first portion 2502 of the catheter 2500 may be between about 1 cm and about 10 cm, between about 1 cm and about 5 cm, between about 5 cm and about 10 cm, and between about 3 cm and about 7 cm, inclusive of all ranges and subranges therebetween.

[0205] The second portion 2504 of the catheter 2500 may have a length L4 and comprise a taper. In some embodiments, the length L4 of the second portion 2504 of the catheter 2500 may be between about 1 cm and about 30 cm, between about 1 cm and about 15 cm, between about 15 cm and about 30 cm, and between about 10 cm and about 20 cm, inclusive of all ranges and subranges therebetween.

[0206] The third portion 2506 (e.g., proximal portion) of the catheter 2500 may have an inner diameter 04 and may be coupled to a push wire 2508. The inner diameter 02 of the first portion 2502 may be less than an inner diameter 04 of the third portion 2506. In some embodiments, the inner diameter 04 of the catheter 2500 may be between about 0.027 inches and about 0.055 inches, between about 0.027 inches and about 0.034 inches, between about 0.034 inches and about 0.055 inches, and between about 0.030 inches and about 0.037 inches, inclusive of all ranges and subranges therebetween

[0207] FIG. 25B is a schematic cross-sectional side view of a perforating device (e.g., shaft) 2510 configured to be disposed within the lumen 2501 of the catheter 2500 and includes a coupling portion 2514 (e.g., protrusion, bump) configured to mate with the first portion 2502 (e.g., catheter coupling portion) of the catheter 2500. The perforating device 2510 may comprise a first portion 2512, a second portion 2516, and a third portion 2518. The first portion 2512 may correspond to a distal portion of the perforating device 2510 and comprise a perforating element 2513 and the coupling portion 2514. Additionally or alternatively, the coupling mechanism of catheter assembly 2520 (e.g., coupling portion 2514 and first portion 2502) may comprise any of the coupling mechanisms described herein.

[0208] The first portion 2512 of the perforating device 2510 may have a length Li and an inner diameter 0i. In some embodiments, the inner diameter 0i of the first portion 2512 of the perforating device 2510 may be between about 0.010 inches and about 0.018 inches, between about 0.010 inches and about 0.014 inches, between about 0.014 inches and about .018 inches, and between about 0.012 inches and about 0.016 inches, inclusive of all rangesand subranges therebetween. In some embodiments, the length Li of the first portion 2512 of the perforating device 2510 may be between about 3 cm and about 20 cm, between about 3 cm and about 12 cm, between about 12 cm and about 20 cm, and between about 8 cm and about 15 cm, inclusive of all ranges and subranges therebetween. In some embodiments, the first portion 2512 may have a constant diameter 0i. The coupling portion 2514 of the perforating device 2510 may have an outer diameter 02 substantially matching the inner diameter 02 of the first portion 2502 of the catheter 2500. For example, the outer diameter 02 of the coupling portion 2514 may be between about 0.018 inches and about 0.027 inches, between about 0.018 inches and about 0.023 inches, between about 0.023 inches and about 0.027 inches, and between about 0.020 inches and about 0.025 inches, inclusive of all ranges and subranges therebetween.

[0209] The second portion 2516 of the perforating device 2510 may have a length L2 and comprise a taper. In some embodiments, the length L2 of the second portion 2516 of the perforating device 2510 may be between about 1 cm and about 30 cm, between about 1 cm and about 15 cm, between about 15 cm and about 30 cm, and between about 10 cm and about 20 cm, inclusive of all ranges and subranges therebetween.

[0210] The third portion 2518 (e.g., proximal portion) may have an outer diameter 03. In some embodiments, the outer diameter 03 of the perforating device 2510 may be less than an inner diameter 04 of the third portion 2506 of the catheter 2500. In some embodiments, the outer diameter 03 of the perforating device 2510 may be between about 0.018 inches and about 0.038 inches, between about 0.018 inches and about 0.028 inches, between about 0.028 inches and about 0.038 inches, and between about 0.023 inches and about 0.033 inches, inclusive of all ranges and subranges therebetween.

[0211] FIG. 25C is a schematic cross-sectional side view of a catheter assembly 2520 including the perforating device (e.g., shaft) 2510 coupled to the catheter 2500 via respective first portion 2502 and coupling portion 2514. In some embodiments, one or more of the first portion 2502 and coupling portion 2514 may comprise a fiducial configured to facilitate confirmation of coupling between the perforating device 2510 and catheter 2500. When coupled, a predetermined length Ls of the perforating device 2510 may extend distal to a distal end 2502 of the catheter 2500. In some embodiments, the length Ls of the perforating device 2510 may be between about 0.1 cm and about 15 cm, between about 0.1 cm and about8 cm, between about 8 cm and about 15 cm, and between about 5 cm and about 10 cm, inclusive of all ranges and subranges therebetween. Additionally or alternatively, the catheter 2500 and perforating device 2510 may be configured to couple via an interference fit where the inner diameter 04 of the third portion 2506 of the catheter 2500 may substantially match the outer diameter 03 of the third portion 2518 of the perforating device 2510. In this manner, the catheter assembly 2520 including the coupled catheter 2500 and perforating device 2510 may provide sufficient stiffness and strength to facilitate transvascular passage through a vessel wall and / or dura and into an extravascular intracranial space.Perforating Device or Shaft

[0212] The perforating devices (e.g., shafts) described herein may be configured to fulfill a complex set of requirements. In some embodiments, a catheter assembly may be navigated intracranially through the MMA and have a perforating device configured to self-orient within the MMA for forming an opening in the MMA and dura in a predetermined orientation (e.g., direction away from the skull), as well as indicate to the operator that the perforating device has completed self-orientation. For example, for middle meningeal artery transvascular access, the combination of opposing curves (e.g., proximal curve, distal curve) along different segments of the perforating device may be configured to induce perforating device rotation (e.g., self-orientation) to align a proximal curve of the perforating device to a curvature of the foramen spinosum and middle cranial fossa (e.g., lateral concavity), and to align a distal curve of the perforating device to a curve of the cranial fossa and cranial vault (e.g., medial concavity).

[0213] The perforating device may be configured to form a transvascular opening having a length, width, and / or diameter sufficient for passage of a catheter such as, for example, the catheter 510 described herein (e.g., drainage catheter, 0.027 inch microcatheter, elongate body). For example, the transvascular opening can be circular oval or longitudinal (e.g., slit). In some embodiments, the perforating device 520 may comprise a plurality of portions having one or more different diameters, shapes, durometers, and the like. For example, a multi-durometer perforating device 520 may be formed by combining a proximal stainless steel core wire having a first stiffness with a distal nitinol wire having a second stiffness less than the first stiffness. Additionally or alternatively, the nitinol wire may be tapered in order to provide proximal stiffness with progressively decreasing distal stiffness.

[0214] In some embodiments, the perforating device 520 may be coupled to the signal generator 560. As described in more detail herein, the perforating device 520 may include a distal tip portion 522 having a perforating element 524 configured to create (e.g., form) an opening in a wall of a blood vessel and a dura of the subject. For example, the perforating device 520 may be configured to form a transvascular passageway into an intracranial space using electrocautery. In some embodiments, the perforating device 520 may have a predetermined bias configured to orient a predetermined portion of the perforating device 520 in a predetermined orientation as the perforating device 520 is advanced into an extravascular intracranial space.

[0215] In some embodiments, the perforating device may be configured to prevent extravasation of fluid. For example, the perforating device may include one or more of a taper, focal enlargement in the outer diameter, surface modifications, expandable elements, and the like.

[0216] In some embodiments, the perforating device 520 may have a predetermined shape at a predetermined portion (e.g., at a focal point along its length) configured to steer the advancing catheter away from a dural edge at an arteriotomy / durotomy site. In some embodiments, the predetermined shape may include one or more of a linear shape, J-shape, U-shape, C-shape, V-shape, an M-shape, an S-shape, a T-shape, an I-shape, a helix, a spiral, a coil, and combinations thereof. For example, the shape may form a mountain-like shape configured to force an edge away or lift the dura.

[0217] In some embodiments, the perforating device 520 may include shape memory material (e.g., nitinol) wire having a polymer jacket. As described in more detail herein, the different shapes and configurations of the perforating device may improve one or more of flexibility, pushability, and support.

[0218] In some embodiments, the perforating device may be formed having a set of constant diameter distal segments and proximal segments having different diameters between about 0.014 inches and 0.027 inches, inclusive of all ranges and subranges therebetween.

[0219] In some embodiments, the shape memory material of the perforating device may have a proximal diameter of between about 0.010 inches and about 0.025 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the shape memory material ofthe perforating device may have a tapered distal diameter of between about 0.006 inches and about 0.014 inches, inclusive of all ranges and subranges therebetween.

[0220] In some embodiments, the distal segment of the shape memory material may be flattened to a width of between about 0.008 inches and about 0.018 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the distal segment of the shape memory material may have a thickness of between about 0.003 inches and about 0.008 inches, inclusive of all ranges and subranges therebetween.

[0221] In some embodiments, a perforating device may be configured to be slidably disposed within a lumen of a catheter. For example, the perforating device may be configured to be advanced distally from a distal end of the catheter and into a blood vessel (e.g., MMA) of a subject. The perforating device may include a perforating tip optionally including an energy element. The energy element may be configured to generate RF energy to form an opening through a wall of the blood vessel and dura of the subject and into an extravascular space of the subject. A curved section may be configured to be radially constrained within the lumen of the catheter. The curved section may be configured to curve toward the wall of the blood vessel and the dura upon exiting the lumen of the catheter such that the energy element is positioned to form the opening.

[0222] In some embodiments, the perforating device may include one or more lumens with one or more openings. The one or more lumens may be configured for one or more of fluid injection and aspiration (e.g., for coupling). For example, injection of a non-ionic dextrose through a first lumen of the perforating device during RF energy delivery may reduce or eliminate alternative current paths and result in more efficient vaporization of a target tissue. A second lumen of the perforating device may be configured to provide aspiration (e.g., suction) to improve wall apposition to the RF electrode and / or collapse an arterial vessel during RF mediated arterial occlusion. In some embodiments, a proximal end of the perforating device may be coupled to a signal generator (e.g., RF generator) via a pushbutton electrosurgical pencil.

[0223] In some embodiments, a perforating device 520 may be configured to have a predetermined shape based on a predetermined transvascular location to direct the perforating device 520 (e.g., a perforation element 524) into an extravascular space with a predetermined trajectory. In some embodiments, a method of forming a passageway through a wall of anintracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within the intracranial vessel. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. The perforating element may be directionally guided towards a wall of the intracranial vessel and the dura using anatomical features proximate to the intracranial vessel. The wall of the intracranial vessel and the dura may be obliquely perforated using the perforating element while the perforating element is directionally guided toward the wall of the intracranial vessel and the dura to form a passageway into the intracranial extravascular space. For example, FIG. 21 is an X-ray image 2100 of arterial blood flow (e.g., MMA) in a head of a subject including a first vascular segment 2110, a second vascular segment 2120, and a third vascular segment 2130 that may be selected for perforation through a vessel wall. In some embodiments, a first perforating device (e.g., shaft) 2112 having a curved shape may be selected for use in the first vascular segment 2110 in order to direct a perforation element into the subdural compartment and due to the decreasing diameter of the vessel. A second perforating device (e.g., shaft) 2122 having a linear shape may be selected for use in the second vascular segment 2120 since the vasculature and adjacent bone structure directs a perforation element into the subdural compartment. A third perforating device (e.g., shaft) 2132 having a J-shape may be selected for use in the third vascular segment 2130 since the vasculature has a relatively larger diameter to facilitate directional perforation into the subdural compartment. In each of these segments, one or more anatomical features of nearby structures (e.g., skull) can be used to directionally guide or point the perforating device toward the wall of the vessel and / or dura. For example, such features can include a bony ridge of the inner surface of the skull, a bony overhang, or a bony channel.

[0224] In some embodiments, a trajectory of a catheter assembly within an extravascular space may depend on a combination of a geometry (e.g., curvature) of the catheter assembly, a geometry of the vessel (e.g., MMA) in which the catheter assembly is disposed, a geometry of an inner table of the skull (e.g., MMA groove) from a perforation point for about 20 mm of a distal end of the catheter assembly. For example, FIG. 22A is a schematic cross-sectional side views of a catheter assembly 2210 (e.g., perforating device) in a head of a subject. A perforating device (e.g., shaft) having a curved distal portion with a radius of curvature smaller than a curvature of the MMA (which follows the curve of the inner surface of theskull) may bias to transverse the vascular wall and dura and emerge into the subdural space following an oblique trajectory (e.g., path). For example, as shown in step 2200 in FIG. 22A, the perforating device 2210 may be disposed within the MMA 2204 prior to generating transvascular passageway through the dura 2206. In step 2202, the perforating device 2210 may create an opening in a wall of the intracranial blood vessel 2204 and dura 2206 at an oblique relative to the vessel 2204. For example, the perforating device 2210 may comprise a curve or predetermined bias.

[0225] As shown in the cross-sectional side views 5003-5005 of FIG. 50B, the MMA 5016 is situated anatomically between the dural membrane 5020 and the bone of the skull 5012. Due to this anatomy, the meningeal arteries and veins create grooves 5015 in the skull as shown in top views 5003 and 5008 of respective FIGS. 50A and 50C. These grooves 5015 define a rigid pathway for the catheter assembly (e.g., access device, therapy device) described herein. In some embodiments, the grooves 5015 in the skull 5012 by which the meningeal arteries and veins traverse may be configured to directionally point the distal tip of the device (e.g., catheter assembly, access device, therapy device, etc.) laterally or medially along a convexity of the skull 5012. In some anatomies, the skull 5012 forms a bony prominence 5014, as shown in images 5006-5008 of FIG. 50C, including an overhang that covers (e.g., overlying, on top of) a vessel (e.g., artery, vein). Accordingly, the bony prominence 5014 may prevent a perforating element from directionally traversing through the bony prominence 5014 to the top of the skull 5012 in the subdural space 5030. However, in some embodiments, the bony prominence 5014 can be used advantageously if the perforation of the vessel wall and dura 5020 is located adjacent the overhang where the bony prominence 5014 can be used to mechanically direct a trajectory of the perforating element, similar to the embodiment described in FIG. 22C. For example, if the perforation point of the vessel and dura 5020 is formed proximal to the bony prominence 5014, then the bony prominence 5014 can be used to bias (e.g., guide, direct) the catheter assembly into the subdural space 5030 (e.g., SDH) by pushing the catheter assembly distally against the bony prominence 5014 to facilitate transvascular access. In some embodiments, if a perforation point is distal to the bony prominence 5014, the overhang can be used to bias the catheter assembly into the subdural space 5030 (e.g., SDH) by pulling the catheter assembly proximally against the bony prominence 5014 to facilitate transvascular access.

[0226] In some embodiments, the bony groove 5015 can be used to facilitate transvascular access. For example, a distal end portion of a perforating element can include a radially expandable portion (e.g., a basket, whisk). In some embodiments, the radially expandable portion 5010 may be configured to transition to an expanded configuration having a diameter between about 0.1 mm and about 80.0 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the radially expandable portion 5010 may include one or more electrodes (e.g., wires) that may be activated with RF energy. The electrodes of the expandable portion 5010 may have one or more of a round, square, and flat shape. In some embodiments, the radially expandable portion 5010 can be disposed in the bony groove 5015 and can press into the dura 5020 as the radially expandable portion transitions to the expanded configuration. The radially expandable portion 5010 in the expanded configuration may expand into the subdural space 5030 as the diameter of the expandable portion 5010 increases beyond the diameter of the bony groove 5015 such that the radially expandable portion 5010 is mechanically forced out of the bony groove 5015. Thereafter, the radially expandable portion may be energized (e.g., activated) such that tissue (e.g., vessel wall, dura) is vaporized, thereby creating a transvascular passageway between the vessel and subdural space 5030. In some embodiments, a bony prominence 5014 can be used as an advantage in achieving transvascular access using the aforementioned methodology. For example, the bony prominence 5014 may provide a counterforce to push and / or guide the perforating element toward the dura 5020 and into the subdural space 5030.Distal Tip Portion

[0227] In some embodiments, a perforating element 524 of a perforating device 520 may include an electrode (e.g., RF ablation tip). Delivery of RF energy using an electrode may rapidly increase tissue temperature to convert fluid to steam (e.g., vaporization), resulting in focal tissue disruption and void. Vaporization may result in a fenestration from the vascular lumen (and through the dura) to the intracranial compartment.

[0228] In some embodiments, penetration of the dura may be achieved with mechanical (e.g., cutting) elements. In some embodiments, the perforating device may include a needle configured to mechanically perforate the wall of the intracranial vessel to form the passageway into the intracranial extravascular space. In some embodiments, the needle may include one or more of an angled opening, a circumferential spiral cut opening, a spiralopening, or external threading. For example, a needle penetration force of between 0.29 to 1.29 N (0.68 ± 0.24 N) may be required to penetrate the dura such that the dura is a very resistant tissue requiring both high sharpness and strong penetrating forces. However, conventional sharp needle tips may result in catheter skiving or scratching along curvatures and unintended brain perforation. Furthermore, high penetration forces require high catheter column strength and pushability, which are obtained by using stiff materials and construction that oppose the strength and pushability requirements for navigating conventional catheters through tortuous vascular geometry. In some embodiments, a distal tip portion 522 of a perforating device 520 may have a tip bending stiffness between about 0.5 gf and about 15 gf (e.g., when a distal end of the perforating device 520 is attached about 5 mm, about 10 mm, and about 20 mm from a distal end of the distal tip portion 522), inclusive of all ranges and subranges therebetween.

[0229] RF tissue ablation without mechanical cutting may allow the perforating device 520 to have reduced column strength compared to mechanical cutters such as needles that require high pushability. Furthermore, an atraumatic perforating element may be less likely to damage a catheter 510 relative to a perforating device having a needle (or other mechanical cutting) tip. Ablation resulting in voided tissue may also reduce edge catching as a catheter 510 is advanced through the tissue opening. In some embodiments, a distal portion (e.g., up to about 300 mm from the distal tip portion 522) of the perforating device 520 may have a column strength of up to about 50 gf, between about 10 gf and about 50 gf, between about 50 gf and about 100 gf, inclusive of all ranges and subranges therebetween

[0230] In some embodiments, RF energy may be used to facilitate ingress into a hematoma through one or more of the surrounding membranes, perforation of septations associated with mixed-aged SDH and chronic SDH, and unclogging of a catheter. Furthermore, RF energy may be used to coagulate tissue to facilitate one or more of tissue opening formation and closure. In some embodiments, catheter assemblies described herein can include a coagulation device configured to apply energy to coagulate an intracranial vessel.

[0231] In some embodiments, an energy delivery device may be configured to be advanced through the lumen and into the intracranial vessel. For example, the perforating element 524 may include two or more electrodes. For example, the perforating element 524 may include two or more tubular elements. In some embodiments, a plurality of electrodes may beconnected individually in parallel to a signal generator 560 in a monopolar configuration and share the same grounding pad. In another embodiment, the energy delivery device may be configured to deliver bipolar energy to the intracranial vessel to coagulate the intracranial vessel. For example, a first electrode may be connected to the signal generator 560 and a second electrode may be connected to ground in a bipolar configuration. In a bipolar configuration, the current may be concentrated between the first and second electrode.

[0232] In some embodiments, the perforating element 524 may include a first electrode and the catheter 510 may include a second electrode in a bipolar configuration. In this configuration, the perforating element 524 and the catheter 510 may be advanced concurrently to maintain the current delivered to tissue, or the perforating element 524 may be advanced relative to the catheter 510 to reduce current delivery as tissue is disrupted and decrease the likelihood of brain injury.

[0233] In some embodiments, the perforating element 524 may include one or more of platinum iridium, stainless steel, copper, titanium, and nickel -titanium alloys and be configured as one or more of a fluoroscopic marker and RF electrode. For example, at least one of the elongate body (e.g., catheter) or the perforating device may include one or more fluoroscopic markers configured to be imaged by a visualization device to indicate a location or a configuration of the at least one of the elongate body or the perforating device. The perforating element 524 including an electrode may be coated with one or more silver and gold to reduce tissue sticking and electrode charring. The perforating element 524 may have an atraumatic shape (e.g., tubular, blunt, rounded distal end). For example, the perforating element 524 may have a shape including one or more of tapered, a bullet, a cone, a truncated cone, a cylinder, a sphere, a dome, a ring, a semi-annular shape, an ellipse, a bevel, and an arrowhead. In some embodiments, an electrode of the perforating element 524 may be uninsulated or partially insulated and may be made of and / or coated with a conductive and a biocompatible material with high radiopacity such as stainless steel, silver, gold, platinum, combinations thereof, and the like. In such embodiments, the perforating device may be covered with an insulating material such as PTFE, polyolefin, paraffin, of the like with a thickness of between about 0.0005 inches and about 0.0010 inches along its length, with the electrode at its distal end being uninsulated or covered in a conductive material.

[0234] In some embodiments, an uninsulated portion of the perforating element 524 may have an area of less than about 16 mm2, between about 1 mm2and about 16 mm2, between about 1 mm2and about 10 mm2, between about 5 mm2and about 15 mm2, between about 10 mm2and about 15 mm2, between about 1 mm2and about 5 mm2, and between about 1 mm2and about 5 mm2, inclusive of all ranges and subranges therebetween. In some embodiments, an energy-delivery portion of the perforating element 524 may have a length of between about 1.0 mm and about 2.0 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the perforating element 524 may be configured to deliver a power of between about 10 Watts and about 100 Watts, between about 10 Watts and about 50 Watts, between about 50 Watts and about 100 Watts, between about 20 Watts and about 75 Watts, inclusive of all ranges and subranges therebetween. In some embodiments, the perforating element 524 may be configured to deliver a current density of between about 1,200 A / m2and about 12,000 A / m2, between about 2,000 A / m2and about 10,000 A / m2, between about 2,000 A / m2and about 5,000 A / m2, between about 5,000 A / m2and about 10,000 A / m2, between about 1,200 A / m2and about 6,000 A / m2, and between about 8,000 A / m2and about 12,000 A / m2, inclusive of all ranges and subranges therebetween. In some embodiments, a distal end of the perforating element 524 may be configured to transition between an open configuration and a closed configuration.

[0235] In some embodiments, one or more non -ionic solutions (e.g., dextrose, iodinated contrast) may be delivered to the area around the perforation element during electrode activation in order to minimizes electrode carbonization, minimize localized blood thromboembolism, and concentrate energy at the target tissue by displacing blood, which is highly conductive.

[0236] In some embodiments, a perforating element 524 of a linear perforating device (e.g., shaft) 520 may be configured to create an opening in one or more of a vessel wall and dura having a length greater than a length of the perforating element. The perforating element may be configured to cut, burst, vaporize, burn, and / or slit the vessel wall and dura. In some embodiments, after creating a transvascular opening, the perforating element and the catheter 510 (e.g., drainage catheter, aspiration catheter) may be advanced into the extravascular space (e.g. and expand to form a 3D shape with a volume larger than the vascular lumen) or may remain in the vessel and drain (e.g., suction) fluid into a lumen of the catheter. In embodiments where the catheter is configured to drain or suction fluid while remaining in thevascular lumen, the catheter may include one or more features (e.g., funnels, baskets, coils) configured to maintain the transvascular passageway open and prevent dural leaflets from folding over the catheter.

[0237] FIG. 23 A is a cross-sectional view of a head of a subject including a blood vessel 2310 (e.g., MMA), dura 2320, and extravascular space 2330 (e.g., SDH). FIGS. 23B-23F illustrate various perforating device embodiments in a head of a subject. FIG. 23B depicts a perforating device (e.g., shaft) 2340 having a linear shape and a perforation element 2342 at a distal tip portion of the perforating device 2340. The perforation element may be coupled to an energy source such as an RF energy source and configured to be energized while being retracted proximally along a predetermined length of the vessel wall 2310 and dura 2320 to create an opening 2322 (e.g., longitudinal slit, window) having the predetermined length.

[0238] As shown in FIG. 23C, a perforation element (e.g., distal tip) of perforating device (e.g., shaft) 2350 may be angled relative to a longitudinal axis of the perforating device 2350 to facilitate creation of an opening 2322 in one or more of the vessel wall 2310 and dura 2320. For example, the perforation element 2352 may comprise an angle relative to the longitudinal axis of the perforating device 2350 of between about 60 degrees and about 120 degrees, between about 60 degrees and about 90 degrees, between about 90 degrees and about 120 degrees, and between about 80 degrees and about 100 degrees, inclusive of all ranges and subranges therebetween. In some embodiments, a portion of the perforation element may be angled relative to the longitudinal axis of the perforating device 2350, the portion having a length of between about 0.1 mm and about 5 mm, between about 1 mm and about 5 mm, between about 3 mm and about 5 mm, between about 0.1 mm and about 3 mm, between about 0.1 mm and about 1 mm, and between about 2 mm and about 4 mm, inclusive of all ranges and subranges therebetween. The perforation element (e.g., bare metal) of the perforating device 2350 may be coupled to an energy source such as an RF energy source and configured to be energized while being retracted proximally along a predetermined length of the vessel wall 2310 and dura 2320 to create an opening 2322 having the predetermined length. Additionally or alternatively, the angled portion of the perforation element may comprise a mechanical cutter (e.g., blade) configured to cut one or more of the vessel 2320, dura 2320, and SDH membranes 2330 during one or more of advancement and retraction.

[0239] In some embodiments, a distal portion of a perforating device of a catheter assembly 2360 may comprise a predetermined (e.g., pre-formed, pre-shaped) bias when unconstrained. As shown in FIG. 23D, the perforating device may transition from a linear shape when constrained by the vessel wall 2310 to a J-shape as an opening 2322 is formed in one or more of the vessel wall 2310, dura 2320, and SDH 2330. For example, once a perforating element 2362 of the catheter assembly 2360 penetrates the vessel wall and / or dura distally using RF energy, the kinetic energy built up in the biased perforating device may be released, thereby allowing the perforating device to curl back on itself and enlarging the opening 2322 in the vessel wall and / or dura as it returns to its unconstrained shape. Alternatively, the J-shape can “knuckle” (e.g., form the J-shape, curve, form an angle, etc.) in the vessel and transition from the knuckled J-shape to a straight configuration as a result of one or more of stored (e.g. built up) kinetic energy and the perforating device becoming unconstrained during the perforation.

[0240] In some embodiments, the perforating element 2372 of a perforating device of a catheter assembly 2370 may comprise an expandable member (e.g., inflatable member, balloon) configured to inflate to facilitate creation of a transvascular passageway to an extravascular space. As shown in FIG. 23E, the perforating element 2372 may comprise a conductive wire disposed around the expandable member (e.g., in a spiral pattern,), the wire configured to receive RF energy to create an opening 2322 in one or more of the vessel wall 2310, dura 2320, and SDH membranes 2330.

[0241] In some embodiments, a distal portion of a perforating device of a catheter assembly 2380 may comprise a predetermined S-shape when unconstrained. As shown in FIG. 23F, the perforating device may transition from a linear shape to an S-shape as an opening is formed in one or more of the vessel wall 2310, dura 2320, and SDH 2330. For example, the perforation element 2382 having a predetermined length may be coupled to an energy source (e.g., RF energy source) and configured to be energized while being rotated so as to create an opening 2322 through one or more of the vessel wall 2310, dura 2320, and SDH 2330 having the predetermined length.

[0242] FIG. 45A illustrates respective perforating elements 4550 on a distal portion 4540 having different shapes (e.g., a fixed shape) of a shaft 4530 (e.g., a guidewire) configured to facilitate creation of a transvascular passageway (e.g., opening through a vessel and dura). For example, as depicted in FIG. 45A, the distal portion 4540 may be straight, acutely angled,bent to 90 degrees, obliquely angled, partially and / or fully curved. In some embodiments the distal portion 4540 of the perforating device 4530 can take a geometric shape such as a diamond, square, triangle, polygon, circle, oval, spiral, “S” shape, “Z” shape, combinations thereof, and the like. In some embodiments, the shape can be skewed to have an extreme angled feature at or near the distal end of the perforating device 4530 such that the perforating device more effectively contacts the vessel and dura. For example, the perforating device may include sharp transitions (e.g., acutely angled portions) at the distal end and / or have a feature with a larger width at the distal end. In some embodiments, the distal portion 4540 of the perforating device 4530 can be planar. In some embodiments, the distal portion 4540 of the perforating device 4530 can be multidimensional with between about 2 and about 180 separate distal shapes, between about 2 and about 100 distal shapes, between about 2 and about 50 distal shapes, between about 2 and about 30 distal shapes, between about 2 and about 20 distal shapes, and between about 2 and about 10 distal shapes, inclusive of all ranges and subranges therebetween. For example, the distal portion 4540 of the perforating device 4530 may diverge into a plurality of distal shapes (e.g., between about 2 and about 180 shapes). These distal shapes can be between about 1 mm and about 40 mm in a dimension (e.g., diameter, width), between about 1 mm and about 10 mm, between about 10 mm and about 20 mm, between about 20 mm and about 30 mm, between about 30 mm and about 40 mm, inclusive of all ranges and subranges between. In some embodiments, the distal shapes can be between about 1 mm and about 100 mm in length, between about 1 mm and about 75 mm in length, between about 1 mm and about 50 mm in length, between about 1 mm and about 25 mm in length, between about 25 mm and about 100 mm in length, and between about 50 mm and about 100 mm in length, between about 75 mm and about 100 mm in length, between about 20 mm and about 80 mm in length, and between about 40 mm and about 60 mm in length, inclusive of all ranges and subranges therebetween. These dimensions may be specific to the anatomy for transvascular access such that the diameter enables the device to perforate (e.g., cut) the tissue and / or mechanically push out of the perforation using the skull bone or an overhang of the skull bone as a backstop.

[0243] In some embodiments, the distal portion of the perforating device (e.g., any of the shapes shown in FIG. 45 A and described herein) may be constrained in the catheter during delivery and may be configured to self-expand as the perforating device is extended into the vessel and / or as the catheter is withdrawn relative to the perforating device, thereby exposingthe distal portion of the perforating device to contact with a vessel wall and dura for creation of the transvascular passageway. For example, the distal shape can be formed or set to be larger than the diameter of the vessel and the wall of the dura when the perforating device is in the relaxed (e.g., unconstrained, expanded, etc.) configuration such that when the perforating element is activated (e.g., energized with RF energy) it can vaporize the tissue to form a transvascular passageway. In some embodiments, the perforating element may be twisted, torqued, or rotated from a proximal end of the perforating device (e.g., by the user) to enable circumferential vaporization (e.g., ablation) of the tissue (e.g., a 360 degree rotation) to form the transvascular passageway. In some embodiments, the shapes of the distal portion of the perforating device can be formed by heat shaping a metallic shaft and / or in the case of geometric shapes, for example, a combination of heat shaping of two or more wires and joining the wires together to form the desired shape.

[0244] FIG. 45B depicts a perforating element of a perforating device (e.g., shaft) in a head of a subject including bone 4580, a vessel 4582, dura 4584, a brain 4586, and an extravascular space (e.g., SDH) 4588. In particular, cross-sectional view 4500 of FIG. 45B shows an example of a distal portion 4540 of a perforating device 4530 including a perforating element 4750 in a delivery (e.g., constrained) configuration in a catheter 4560 (top panel) and the cross-sectional view 4502 of FIG. 45B shows an unconstrained (e.g., relaxed) configuration outside of the catheter 4560 (bottom panel). As shown, the distal portion 4540 in the unconstrained configuration may expand to at least a width of the vessel 4582 in which it is disposed to contact the vessel walls.

[0245] As shown in cross-sectional views 4600-4608 of respective FIGS. 46A-46E, a catheter assembly can include a perforating device (e.g., shaft) 4610 including a perforating element including an S-shape distal portion (e.g., undulating, serpentine shape, sinusoidal shape, etc.). The distal portion may be configured to cross into the intracranial space 4630 such that a catheter can be disposed therethrough (e.g., the catheter 4640 may follow the perforating element 4610 into the intracranial space 4630 from the vessel 4614 as shown in FIG. 46C). For example, when the perforating element 4610 is distal to a catheter 4640 and in an unconstrained configuration (FIG. 46 A), the S-shape can form and contact the vessel 4614 wall and dura 4620 and can be forced or pushed into the intracranial space 4630 by the resistance encountered by the distal portion against the skull bone 4612 (FIG. 46B). When the perforating element 4610 (e.g., the S-shape) is activated (e.g., one or more electrodes areactivated), the perforating element 4610 may create an opening (e.g., passageway) 4650 through the vessel 4614 wall and dura 4620 into the intracranial space 4630 by ablating a portion of the vessel 4614 and dura 4620. In some embodiments, the perforation element 4610 can be rotated or torque (e.g., 0 to 360 degree rotation or more) to cause radial perforation, thereby ensuring that a perforation is formed. As shown in image 4606 of FIG. 46D, once the perforating element 4610 is disposed in the intracranial space 4630, the catheter 4640 may be advanced over the perforating element 4610 and into the subdural space. The shape of the perforating element 4610 (e.g., the S-shape) can cause the catheter 4640 to take the same shape of as the perforating element 4610, thereby indicating to the user that the catheter 4640 system is in the intracranial space 4630, as shown in FIG. 46D. Alternatively, the S-shape distal portion may not retain its shape when the catheter 4640 is slidably forced over the shaft (e.g., guidewire) even when access to the SDH 4660 has been made, as shown in FIG. 46E.

[0246] In some embodiments, the perforating element of a perforating device (e.g., shaft) 4702 may include a perforating element 4710 having a mechanically expandable (e.g., radially expandable) portion configured to cross into the subdural space 4730, as shown in FIGS. 47A-47C. In some embodiments, the perforating element 4710 may be coupled to a pull wire 4740 configured to transition the perforating element 4710 between a delivery configuration (e.g., unexpanded, relaxed, closed, extended configuration, etc.) and an expanded configuration (open configuration, compressed configuration, treatment configuration). For example, when the perforating element is in a delivery configuration with no tension on the pull wire 4740, the perforating element 4710 can have a diameter that corresponds to or is smaller than (e.g., consistent with, substantially equivalent to, etc.) the diameter of the vessel 4750. When the pull wire 4740 is pulled into tension using an actuator 4720 on a handle of the catheter assembly by the user, the perforating element 4710 can expand radially larger than the diameter of the vessel 4750 and dura 4752 such that the perforating element 4710 presses against the skull 4754 and the vessel wall 4750, as shown in FIG. 47B and 47C. When the perforating element 4710 (e.g., comprising an electrode) is activated, the tissue (e.g., vessel 4750, dura 4752) is vaporized and a transvascular passageway 4760 is formed. The pull wire 4740 can then be relaxed or pushed distally such that the perforating element 4710 transitions to the delivery configuration. When the perforating element 4710 is transitioned to the delivery configuration, a catheter 4712 canslidably translate over the perforating element 4710 and be disposed within the intracranial space 4730.

[0247] FIG. 48 shows respective side views and front views of perforating devices having a mechanically expandable distal portion in a delivery configuration 4800 and an expanded configuration. In some embodiments, when a pull wire is put in tension, the perforating device may transition to an expanded configuration having a shape including a linear basket 4802, spiral basket 4804, a single curved (e.g., arched) wire 4806, a diamond shaped basket 4808, 4816 with singular or multiple connections along the extended distal pull wire, a deflecting wire 4810, a single spiral wire 4812, and a single curved (e.g., arched) wire 4814 with a helix or a plurality of wires around a longitudinal axis of the curved wire .

[0248] In some embodiments, a distal portion of a perforating device 4910-4916 illustrated in respective FIGS. 49A-49G can include an electrode of a perforating element 4930 that can be connected to a proximal connector (e.g., Luer connector), as depicted in FIG. 49H, to a radiofrequency generator or radiofrequency surgical accessory via a wire that runs along a length of the perforating device from the electrode to the connector. In some embodiments, a catheter assembly including a perforating device 4910-4916 can be slidably disposed in a vessel 4950 (e.g., artery, vein) such as the middle meningeal artery, for example, over a prepositioned guidewire 4908. The guidewire 4908 can be electrically non-conductive, include an electrically non-conductive portion, and / or be dielectrically insulated along the full length of the guidewire 4908 to prevent the guidewire 4908 from becoming energized when exposed to radiofrequency energy.

[0249] In some embodiments, the distal portion of the perforating device 4910-4916 can include one or more electrodes 4930 and may be positioned in the vessel 4950 where one or more of the electrodes of the perforating element 4930 can be activated with energy (e.g., radiofrequency energy) such that the surrounding tissue is vaporized to create an opening 4960 (e.g., transvascular passageway) between the subdural space and vessel 4950. In some embodiments, the wall of the vessel 4950 and dura 4920 may be the only tissue ablated because the vessel 4950 runs between the dura 4920 and the skull 4912, such that the skull bone 4912 (i.e., any bony area) in the vicinity of the electrode 4930 remains unaffected by the applied energy. In some embodiments, once the opening 4960 is formed in the vessel wall and / or dura, the perforating device 4910-4916 may be retracted proximal to the opening 4960to allow for one or more of the guidewire 4908, catheter, access device, and the like to traverse the opening 4960 into the subdural space, thereby creating a conduit for access and delivery devices to treat the subject.

[0250] In some embodiments, a diameter of a distal portion of the perforating device can be between about 0.014 inches and about 0.080 inches, between about 0.014 inches and about 0.050 inches, between about 0.014 inches and about 0.030 inches, between about 0.030 inches and about 0.080 inches, and between about 0.05 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween. In some embodiments, a length of the distal portion of the perforating device can be between about 0.5 cm and about 30 cm, between about 0.5 cm and about 20 cm, between about 0.5 cm and about 10 cm, between about 10 cm and about 30 cm, between about 20 cm and about 30 cm, and between about 10 cm and about 20 cm, inclusive of all ranges and subranges therebetween.

[0251] In some embodiments, the distal portion of the perforating device can be part of or coupled to a catheter having a diameter between about 0.018 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween, between about 0.018 inches and about 0.080 inches, between about 0.018 inches and about 0.060 inches, between about 0.018 inches and about 0.040 inches, between about 0.030 inches and about 0.080 inches, and between about 0.050 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the distal portion of the perforating device can be part of or coupled to a catheter having a length between about 90 cm and about 225 cm in length, inclusive of all ranges and subranges therebetween.In some embodiments, the guidewire may be between about 0.010 inches and about 0.024 inches in diameter, inclusive of all ranges and subranges therebetween. In some embodiments, the guidewire can be between about 90 cm and about 480 cm in length, between about 90 cm and about 400 cm in length, between about 90 cm and about 300 cm in length, between about 90 cm and about 200 cm in length, between about 90 cm and about 150 cm in length, between about 200 cm and about 400 cm in length, between about 250 cm and about 350 cm in length, inclusive of all ranges and subranges therebetween.

[0252] In some embodiments, the electrode 4930 may include one or more conductive, radiopaque portions (e.g., a “C”-shape marker, a marker extending around half of the circumference, or a marker having an arc length that is smaller than the circumference of thedistal perforating device), as shown in FIGS. 49B, 49C, and 49F. In some embodiments, the electrode 4930 may be disposed between about 0.05 mm and about 15 cm from a distal end of the perforating device, between about 0.05 mm and about 10 cm from a distal end of the perforating device, between about 0.05 mm and about 5 cm from a distal end of the perforating device, between about 0.05 mm and about 2 cm from a distal end of the perforating device, between about 10 cm and about 15 cm from a distal end of the perforating device, and between about 5 cm and about 10 cm from a distal end of the perforating device, inclusive of all ranges and subranges therebetween. In some embodiments, a distal portion of the perforating device may include between about 1 electrode and about 15 electrodes, with each electrode disposed at a distance of between about 0.05 mm and about 15 cm from the distal end of the perforating device, inclusive of all ranges and subranges therebetween. In some embodiments the distance between the electrodes may be predetermined. Additionally or alternatively, a distance between the electrodes may be mechanically changed (e.g., increased, decreased) to create an opening 4960 (e.g., transvascular passageway) in the vessel 4950. For example, as shown in FIG. 49B, as the electrodes of the perforating element 4930 create an opening through tissue 4920, 4950, the perforating device (e.g., shaft) 4911 may transition to an expanded configuration such that a first portion 4917 of the perforating device 4911 is spaced apart from a second portion 4918 of the perforating device 4911 which may be large enough to fully occlude the vessel 4950 distal and proximal to the opening 4960 such that fluid may be aspirated through the perforating device 4911 and into the subdural space. The perforating device 4911 may have an outer diameter between about 0.038 inches and about 0.50 inches.

[0253] In some embodiments, a distal end portion of the perforating device 4911 includes a split portion 4917, 4918 (e.g., bifurcation, divergence, branch, etc.) as shown in FIG. 49B, and when tension and / or compression is applied to the distal end portion of the perforating device, the split portion 4917, 4918 can expands into the vessel wall 4950 and dura 4920 using the skull bone 4912 as a backstop such that the distal perforating device 4911 presses firmly against the vessel wall 4950 and dura 4920 while activated. In some embodiments, the split portion 4917, 4918 of the perforating device 491 Ithat expands into the vessel 4950 wall / dura 5020 can include between about 1 electrode and about 15 electrodes disposed along the length of the split portion 4917, 4918. As shown in FIG. 49C, a distal perforating device 4919 may include a plurality of portions (e.g., divergences) such that the distal end portion ofthe perforating device 4919 radially expands (e.g., blooms) about a longitudinal axis of the perforating device when in tension or when the distal end portion of the perforating device4919 is compressed, thereby transitioning the plurality of portions into an expanded configuration that pushes against the vessel wall 4950, dura 4920, and the skull bone 4912. For example, the perforating device 4911 may include between about 2 and about 12 portions configured to expand, with each portion including between about 1 electrode and about 15 electrodes, inclusive of all ranges and subranges therebetween.

[0254] In some embodiments, a distal end portion of the perforating device 4913 as shown in FIG. 49D may include a spiral (e.g., pigtail) shape and a fiducial 4932. In some embodiments, the distal end portion (having the spiral shape) can include between about 1 and about 15 electrodes, inclusive of all ranges and subranges therebetween. In some embodiments, the spiral shape may be pre-formed and / or biased to form the spiral shape when under tension or compression (e.g., a pull wire coupled to the distal perforating device 4913 is tensioned). For example, the distal end portion of the perforating device 4913 may transition between a delivery configuration and an expanded configuration configured to expand into the vessel wall 4950 and dura 4920 using the skull bone 4912 as a backstop such that the distal perforating device 4913 presses firmly against the vessel wall 4950 and dura4920 while activated.

[0255] In some embodiments, a distal end portion of the perforating device 4914 may have a funnel-like (e.g., weaved basket, cone, tapered) structure as shown in FIG. 49E. In some embodiments, the distal end portion can include a conductive material (e.g., a conductive metal and / or polymer) and can be activated and used as an electrode 4930. In some embodiments, the distal end portion can include a non-conductive material, and may include a conductive wire (e.g., a conductive, metal wire) at a distal tip thereof. For example, the conductive wire may be configured to expand circumferentially and be energized. The distal end portion of the perforating device 4914 may transition between a delivery configuration and an expanded configuration configured to expand into the vessel wall 4950 and dura 4920 using the skull bone 4912 as a backstop such that the distal perforating device 4915 presses firmly against the vessel wall 4950 and dura 4920 while activated. In some embodiments, the funnel-like structure may be covered with a polymer (e.g. elastic PTFE) configured to occlude the perforation and vessel, thereby preventing the fluid from entering the intracranialspace or refluxing into the vessel. The covered funnel-like structure may facilitate expanded entry to promote drainage and prevent the SDH membranes from collapsing.

[0256] In some embodiments, a distal end portion of the perforating device 4915 can open or expand a plurality of elongate members (e.g., fingers, projections, extensions, branches, etc.) as shown in FIG. 49F. For example, the distal end portion of the perforating device 4915 may include between about 2 and about 16 fingers, inclusive of all ranges and subranges therebetween. One or more of the elongate members may be independently articulatable such that the distal end portion of the perforating device 4915 may transition between a delivery configuration where the elongate members are substantially in contact with one another to an expanded configuration where at least a portion of an elongate member is spaced apart from (e.g., not in contact with) another elongate member. In some embodiments, each elongate member may include between about 1 electrode and about 15 electrodes, inclusive of all ranges and subranges therebetween. One or more of the plurality of elongate members may be configured to have a predetermined bias to expand into the vessel wall 4950 and dura 4920 using the skull bone 4912 as a backstop such that the distal perforating device 4915 presses firmly against the vessel wall 4950 and dura 4920 while activated.

[0257] In some embodiments, a distal end portion of the perforating device 4916 can include an expandable portion (e.g., expandable balloon) as shown in FIG. 49G. In some embodiments, the expandable portion can be configured to expand to a diameter between about 0.010 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the expandable portion may have a length between about 1.0 cm and about 5.0 cm, inclusive of all ranges and subranges therebetween. In some embodiments, the expandable portion may include between about 1 electrode and about 15 electrodes around a circumference thereof. In some embodiments, the electrodes may include one or more of an expanding metallic mesh, metallic coil, and a singularly placed electrode pad. The distal end portion of the perforating device 4916 may transition between a delivery configuration and an expanded configuration configured to expand into the vessel wall 4950 and dura 4920 using the skull bone 4912 as a backstop such that the distal perforating device 4916 presses firmly against the vessel wall 4950 and dura 4920 while activated.

[0258] In some embodiments, as shown in FIG. 49H, any of the perforating devices described herein (e.g., perforating device 4910-4916) may be connected to one or more of a proximal connector 4970 that defines a first lumen 4972 for one or more of a guidewire, access device, hemostatic device, etc. to translate along the length of the perforating device, a second lumen (e.g., secondary channel, inflation lumen) configured to provide fluid to inflate an expandable member, provide suction, and / or irrigation, and an electrical connector 4980 configured to electrically couple to a signal generator (e.g., power source, radiofrequency generator, radiofrequency surgical accessory).

[0259] FIG. 51 A and 5 IB illustrate a perforating element 5100 including a radially expandable portion (e.g., basket, whisk) 5110 at a distal end thereof. In some embodiments, the expandable portion 5110 may be coupled to one or more of a perforating device 5112, an insertion element, guidewire, and coupling mechanism via a hinge 5108. For example, the hinge 5108 may include one or more radiopaque markers or materials. The expandable portion 5110 may be configured to rotate in one or more degrees of freedom relative to the perforating device 5112 using the hinge 5108.

[0260] FIG. 5 IB shows a method for forming a transvascular passageway using the perforating element 5110. As described herein, a transvascular opening may facilitate access to an extravascular space (e.g., subdural compartment). For example, any of the catheter assemblies described herein may be configured to drain an SDH through the openings created by the shaft where the catheter may be disposed in each of the SDH, transvascular opening, and vessel. In some embodiments, the perforation element 5110 can be slidably inserted through a catheter 5160 and through a vessel 5150, shown at 5101, where the expandable portion 5110 is in a delivery (e.g., unexpanded) configuration. The expandable portion 5110 may transition to an expanded configuration in 5102 such as by mechanical expansion using a pull wire or when unconstrained by the catheter 5160. As shown in 5102, the perforating element 5110 can be configured to expand in the vessel 5150 to a diameter larger than a diameter of the vessel 5150 to perforate through the vessel wall and surrounding dura 5120 while using the skull bone 5112 as a backstop, shown at 5102, thereby creating a passageway into the intracranial space 5130. As shown in 5103 and 5104, the distal tip of the perforating element 5110 can remain in the vessel 5150 while advancement of the perforating device 5112 rotates the expandable portion 5110 about the hinge 5108 such that a portion of the perforating device 5112 and the expandable portion 5110 are disposed in the intracranialspace 5130. The catheter 5160 may be slidably translated over the perforating device 5112 and through the transvascular passage and into the intracranial space 5130, as shown in 5105 and 5106. Once the catheter 5160 is advanced into the intracranial space 5130, the expandable portion 5110 may transition from the expanded configuration to the delivery configuration, and withdrawn into a lumen of the catheter 5160, as shown in 5107. For example, tension on a pull wire coupled to the expandable portion 5110 may be released to transition the expandable portion 5110 from the expanded configuration to the delivery configuration. Additionally or alternatively, the sidewalls of the catheter 5160 may compress or close the expandable portion 5110 such that the perforating device 5112 and expandable portion 5110 may be withdrawn from the subject through the catheter 5160.

[0261] In some embodiments, a perforating element of a perforating device may have shapes configured to facilitate formation of a transvascular passageway through tissue such as a vessel and dura. In some embodiments, the perforating device may include a paddle structure configured to apply energy to the wall of the intracranial vessel to form the passageway into the intracranial extravascular space. The paddle structure may be configured to act as a heat sink during application of the energy. In some embodiments, the perforating device may include an insulating material disposed along a length of the perforating device proximal of the paddle structure. The paddle structure may have an outer diameter that provides a smooth transition from the insulating material to the paddle structure. For example, a perforating element 2400 of a distal tip portion may comprise an electrode 2410, a conductive wire 2420, and a tapered portion 2430, as shown in the schematic side views of FIGS. 24A-24C. The conductive wire 2420 and a portion of the electrode 2410 may comprise an insulator 2422. For example, the electrode 2410 may comprise a paddle shape configured to provide atraumatic advancement through a vessel and dura by providing a smooth transition between the insulator 2422 and the proximal and distal ends of the electrode 2410. The paddle may provide additional metallic material near the electrode configured to provide a heat sink, thereby localizing the heat effected zone to the paddle and the electrode location and preventing the heat effected zone from traveling proximally into the thinner ground wire, thereby reducing embrittlement of the structure and preventing device failure when delivering RF energy. In some embodiments, the electrode 2410 may have an atraumatic shape (e.g., rounded). For example, an outer diameter of the insulator 2422 may substantially match an outer diameter of the electrode 2410 or the conductive wire 2420 may be coupled (e.g.,welded, soldered) to the electrode 2410. The electrode may be a metallic radio-fluorescent ring or tip such as a domed sleeve 2410 in FIG. 24D comprising a mixture of platinumiridium such as about 90% platinum and about 10% iridium.

[0262] In some embodiments, the electrode 2410 may comprise a diameter of between about 0.35 mm and about 0.70 mm, between about 0.35 mm and about 0.50 mm, between about 0.5 mm and about 0.70 mm, and between about 0.50 mm and about 0.60 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the electrode 2410 may comprise a length of between about 0.7 mm and about 1.5 mm, between about 0.7 mm and about 1.00 mm, between about 1.0 mm and about 1.50 mm, and between about 0.90 mm and about 1.30 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the electrode 2410 may comprise a surface area of between about 1.15 mm2and about 4.75 mm2, between about 1.15 mm2and about 3 mm2, between about 3 mm2and about 4.75 mm2, and between about 2 mm2and about 4 mm2, inclusive of all ranges and subranges therebetween.

[0263] In some embodiments, a single device may be configured to deliver energy (e.g., RF energy) in a bipolar configuration. FIG. 27A is a schematic cross-sectional side view of a perforating device 2700 having a bipolar configuration including a perforating element 2710 and a return electrode 2720 disposed proximal to the perforating element 2710. The perforating element 2710 may be an electrode coupled to a first lead 2712 (e.g., RF supply) having an insulator 2714 along its length. The return element 2720 may comprise a ring electrode coupled to a second lead 2722 (e.g., RF return) having an insulator 2724 along its length. The first lead 2712 and second lead 2722 may be insulated from each other and each couple to a signal generator as described herein. The insulator 2714, 2724 may include a polymer such as PTFE, Polyolefin, polyurethane, and the like. The electrode and ring electrode may be uninsulated. In some embodiments, a distance between the electrode of the perforating element 2710 and ring electrode of the return element 2720 may be between about 1 mm and about 5 mm, between about 1 mm and about 3 mm, between about 3 mm and about 5 mm, and between about 2 mm and about 4 mm, inclusive of all ranges and subranges therebetween.

[0264] In some embodiments, a catheter assembly including a catheter and a perforating device may be configured to deliver energy (e.g., RF energy) where the perforating deviceoperates in a monopolar configuration. FIG. 27B is a schematic cross-sectional side view of a catheter assembly 2702 having a bipolar configuration and including a perforating device 2740 and a catheter 2730 disposed within a lumen of the catheter 2730. The perforating device 2740 may comprise a perforating element 2710 (e.g., electrode) coupled to an insulated first lead 2712 (e.g., RF supply). The catheter 2730 may comprise a return element 2720 including a ring electrode coupled to an insulated second lead 2722 (e.g., RF return). For example, the second lead 2722 may be disposed within a sidewall of the catheter 2730. The first lead 2712 and second lead 2722 may be insulated from each other and each lead may couple to a signal generator as described herein. The electrode and ring electrode may be uninsulated. In some embodiments, a distance between the electrode of the perforating element 2710 and ring electrode of the return element 2720 may be adjustable by translating the perforating device 2730 relative to the catheter 2740. Additionally or alternatively, a catheter assembly may comprise a plurality of pairs of electrodes (e.g., RF supply, RF return) disposed in series along a predetermined length (e.g., up to about 10 cm) of the catheter assembly.

[0265] In some embodiments, a catheter assembly including a perforation element configured to deliver energy (e.g., RF energy) in a bipolar configuration. FIGS. 28A and 28B are schematic cross-sectional side views of a perforation element 2800 including a first electrode 2810 (e.g., RF supply) and a second electrode 2820 (e.g., RF return) in parallel with the first electrode 2810. The perforating element 2800 may comprise an insulator 2830 configured to insulate the first and second electrodes 2810, 2820 from each other and the subject except at a distal end of the electrodes 2810, 2820. Perforation characteristics (e.g., temperature) may be based on the energy waveform delivered and a respective distance yi, yi between the first and second electrodes 2810, 2820. For example, a distal end of the first and second electrodes 2810, 2820 may comprise one or more bends or angles configured to modify (e.g., increase) a distance between the uninsulated portions of the electrodes. In some embodiments, the electrodes 2810, 2820 may be configured with a predetermined bias such that the electrodes 2810, 2820 may have a linear configuration when constrained by a catheter and may transition to an expanded configuration when unconstrained. Additionally or alternatively, each of the electrodes 2810, 2820 may be configured to translate independently with respect to each other.

[0266] In some embodiments, different portions of a perforating element (e.g., perforating wire) may have different characteristics to improve performance based on the anatomy in which it is disposed. For example, FIG. 17A is an X-ray image 1700 of arterial blood flow in a head of a subject where a perforating element 1710 may be advanced within a vessel 1702 (e.g., MMA), as described in more detail herein. The perforating element 1710 may include a distal portion 1712 and a proximal portion 1714. In some embodiments, a distal portion 1712 of the perforating element 1710 may correspond to a transvascular portion configured to facilitate transvascular advancement of the perforating element 1710 from the vessel 1702 to an extravascular intracranial space 1704 (e.g., subdural space). In some embodiments, the distal portion 1712 may have a length of between about 1 mm and about 10 mm, between about 1 mm and about 5 mm, and between about 5 mm and about 10 mm, inclusive of all ranges and subranges therebetween. The distal portion 1712 may have the same distalmost curve as the proximal portion 1714 or have a different angulation or plane. An angulation and plane of the perforating element 1710 may be configured to direct a perforation element cranially or caudally into one or more of the epidural space, intradural corridor, and subdural space. FIG. 17B is a schematic cross-sectional view 1710 of a perforating element 1710 disposed within different planes within a head of a subject.

[0267] In some embodiments, a proximal portion 1714 of the perforating element 1710 may correspond to an orientation portion configured to orient the perforating element 1710 with respect to a geometry of predetermined vasculature. For example, the proximal portion 1714 may be configured to have flexibility, kink resistance, and stiffness sufficient to navigate into the intracranial space, while also having a predetermined (e.g., pre-formed, preshaped) bias when unconstrained. In some embodiments, the predetermined bias of the proximal portion 1714 may correspond to a two-dimensional or three-dimensional shape (e.g., curves). In some embodiments, the proximal portion 1714 may have a length of between about 1 mm and about 100 mm, between about 1 mm and about 50 mm, between about 50 mm and about 100 mm, between about 20 mm and about 80 mm, and between about 40 mm and about 60 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the proximal portion 1714 may have a radius of curvature larger than a radius of a lumen of a vascular structure in which it is disposed. For example, the MMA may have a length between about 10 mm and about 50 mm, and a radius of more than about 5 mm. When the shape of the proximal portion 1714 is substantially similar to the geometry of thevasculature containing the proximal portion 1714, the perforating element 1710 may torque to substantially match the curvature of the proximal portion 1714 to the curvature of the vascular lumen. This release of accumulated elastic energy in the perforating element 1710 may provide rotational movement if it overcomes the friction between the vessel 1702 and perforating element 1710, thereby self-orienting the perforating element 1710 in tortuous vasculature to a predetermined orientation.Linear Device

[0268] In some embodiments, a perforating device assembly such as shaft 520 and shaft assembly 900, including a linear tip RF device (e.g., shaft 3120) configured to create an opening in a vessel wall and / or dura to access, for example, an epidural and / or subdural space. The linear tip RF device may have a shaft and a distal tip portion coupled thereto, where a longitudinal axis of the shaft is parallel to a longitudinal axis of the distal tip portion. That is, the distal tip portion may not form an angle or curve relative to the shaft. The linear tip RF device may be advanced epidurally for a predetermined length to promote distal access to the intracranial space and subjacent tissue. The linear tip RF device may be configured to deliver one or more of energy and / or mechanical force between the bone and tissue (e.g., vessel wall, dura) to create an opening between the intravascular or epidural space and the subdural space. For example, the energy may include one or more of RF energy, pulsed field ablation, microwave, diathermy, laser, electrocautery, and cryogenic energy. In some embodiments, the mechanical forces may include one or more of cutting, tension, compression, bending, torsion, and shear.

[0269] In some embodiments, one or more portions of the shaft may have a cross-section with a first lateral dimension that is greater than a second lateral dimension. In some embodiments, the shaft may include a wider section having a lateral dimension that matches with or substantially matches an inner diameter of the lumen of the catheter to prevent ovalizing of the catheter as the catheter advances through the opening and to facilitate bending of the shaft in a first plane and restrict bending in a second plane perpendicular to the first plane.

[0270] In some variations, a linear tip RF device may have a diameter similar to that of the vessel to be perforated. In some embodiments, a linear tip RF device may be advanced into a intracranial space with a trajectory substantially parallel to a surface of the dura and / or brainsurface in order to prevent brain perforation during advancement into the extravascular subdural space. The linear tip RF device may have a shape that is easily advanced through a sheath and able to penetrate through a membrane of a subdural hematoma. This may facilitate ingress and egress of a catheter (e.g., drainage catheter) into an SDH. For example, the linear tip may include an RF electrode configured to operate in a monopolar configuration. In some embodiments, the second RF device may be configured to deliver RF energy to close a vascular lumen of the blood vessel. For example, when the catheter has been withdrawn from an extravascular space and into a blood vessel (e.g., MMA), the second RF device may be used to seal the opening formed in the MMA. As such, this second RF device can function as a hemostatic device. In some embodiments, a single RF device may be used for transvascular perforation into the subdural space using a monopolar cut mode, arteriotomy, and arterial occlusion using a coagulation monopolar mode. For example, a perforating element having a tip RF electrode composed of platinum iridium may have a length of between about 0.5 mm and about 1.5mm and a diameter of between about 0.015 inches and about 0.03 inches, and may be configured to cut the vascular wall and dura when set in cut monopolar mode with a power of more than about 20 Watts. The perforating element may be configured to occlude the artery in a monopolar coagulation mode with a power of more than about 5 Watts.

[0271] In some embodiments, the linear RF device may be configured in a monopolar or bipolar configuration, single or a plurality of bipolar configuration. In some embodiments, the linear RF device may have a shape corresponding to a ring or a coiled configuration for circumferential thermal ablation. In some embodiments, the coiled configuration may be disposed at a distal end of the linear RF device and have a length of between about 3 mm and about 30 mm, and a diameter of between about 0.01 inches and about 0.05 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the diameter may be continuous or tapered.

[0272] In some embodiments, the linear RF device may include a temperature sensor such as a thermistor and a thermocouple. In some embodiments, the temperature sensor may be thermically isolated from the RF electrode.

[0273] FIGS. 22B and 22C are schematic cross-sectional side views of a catheter assembly2210 in a head of a subject. A catheter assembly 2230 having a linear distal portion may be disposed within a vessel 2204, as shown in step 2220 in FIG. 22B. In step 2222 in FIG. 22B,the linear catheter assembly 2230 may create an opening in a wall of the vessel 2204 and may bias to follow the curvature (e.g., convexity) of the inner skull 2208 within an epidural or intradural space. Access to the intracranial space may subsequently be achieved by creating an opening in the dura. For example, a linear catheter assembly 2230 may be useful for accessing an SDH located higher within the cranial convexity (e.g., in a cranial direction) where the opening in the MMA facilitates advancement of the catheter assembly 2230 through epidural space, thereby minimizing perforation risk to the brain. Once the catheter assembly 2230 is overlying the SDH, an opening in the dura 2206 may be created to access the SDH (not shown for the sake of clarity). In some embodiments, a perforating element having an RF electrode tip may have a diameter of between about 0.010 inches and about 0.20 inches, and a length of between about 0.5mm and about 1.5mm, including all ranges and sub-values therebetween. The perforating element may be advanced epidurally or intradurally when operating in a monopolar cut mode.

[0274] In some methods of use, a bony prominence of the inner surface of the skull may direct a linear shaft towards the dura and the subdural space. For example, a lateral third of the sphenoid ridge (e.g., posterior aspect of the lesser wing of the sphenoid bone) and its continuation along the skull in the pterional region corresponds to a bony prominence that may be configured to direct a linear RF shaft sufficiently medially to create an opening in the vessel wall and dura to gain access to the subdural space. As shown in step 2240 in FIG. 22C, a catheter assembly 2250 having a shaft with a linear distal portion may be disposed within the MMA at a bony prominence 2260. In step 2242, the linear shaft may advance along an angle of the bony prominence 2260 to create an opening in a wall of the intracranial blood vessel 2204 and dura 2206 at an oblique relative to the vessel 2204.Hemostatic Device or Other Implanted Devices

[0275] In some embodiments, a hemostatic device may be configured to occlude the intracranial vessel. In some embodiments, the hemostatic device may include a carrier structure and a hydrogel disposed around the carrier structure, the hydrogel configured to expand to occlude the intracranial vessel. For example, a hemostatic device 530 may include a hemostatic element or an RF device configured to close an opening (e.g., transvascular passageway, perforation) formed by the perforating element 524 of the perforating device 520. The hemostatic device 530 may be optionally coupled to the signal generator 560. Insome embodiments, the catheter 510 may be configured to deliver the hemostatic device 530 to the location of an opening through a vessel wall and / or dura, (e.g., to seal the opening). FIG. 52A illustrates an example of a hemostatic (e.g., embolic, occlusion) device 5200 used to close an opening (e.g., perforation) formed in a vessel (e.g., the MMA). In some embodiments, a hemostatic device 5200 can include a carrier structure 5210 such as a metallic coil, for example. The carrier structure 5210 may include any suitable material such as, for example, platinum, tungsten, platinum-tungsten alloy, gold-tungsten ally, stainless steel, nitinol alloy, or combinations thereof. In some embodiments, the carrier structure 5210 may have an outer diameter between about 0.003 inches and about 0.012 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the carrier structure 5210 may have an inner diameter between about 0.001 inches and about 0.011 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the hemostatic device 5200 may include one or more metallic wires in addition to or in place of the metallic coil 5210. The metallic wire may have a diameter between about 0.0005 inches and about 0.0030 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the metallic wire and / or coil 5210 may include any suitable material such as, for example, platinum, tungsten, platinum-tungsten alloy, gold-tungsten ally, stainless steel, nitinol alloy, polymer filament, and combinations thereof. In some embodiments, a coating 5250 (e.g., hydrogel) may cover the carrier structure 5210. In some embodiments, one or more portions of the carrier structure 5210 may be radiopaque.

[0276] In some embodiments, the coating 5250 (e.g., hydrogel sleeve) may include an outer coil (e.g., a loosely pitched coil) 5240 disposed around the coating 5250. The outer coil 5240 may be formed of a wire having a diameter of between about 0.0005 inches and about 0.005 inches, and the outer coil may have a pitch of between about 0.010 inches and about 0.100 inches, including all ranges and sub-values therebetween. In some embodiments, the outer coil 5240 may have variable pitch along the length of the coil 5240. For example, the pitch near a distal end of the outer coil 5240 may be about 0.001 inches for a length of between about 0.1 cm and about 10.0 cm, and may variably increase by between about 0.001 inches and about 0.010 inches in pitch proximally along the outer coil 5240.

[0277] In some embodiments, the outer coil 5240 may have a diameter larger than a diameter of the coating 5250 such that a metallic wire of the outer coil 5240 may be configured to wrap around the coating 5250. In some embodiments, the outer coil 5240 mayinclude any of the radiopaque materials described herein. In some embodiments, the hemostatic device 5200 in an unhydrated (e.g., dry) state, as shown in 5201, can have a total diameter of between about 0.005 inches and about 0.028 inches, inclusive of all ranges and subranges therebetween.

[0278] In some embodiments, the coating 5250 (e.g., hydrogel) can be configured to expand (e.g., swell), as shown in 5202, when exposed to fluid (e.g., an aqueous environment) to occlude the vessel. For example, the coating 5250 may include one or more polymers including, but not limited to, polystyrene (PS), polybutadiene (PB), polyisoprene (PI), poly(methyl methacrylate) (PMMA), poly(methylacrylate) (PMA), polypropylene oxide) (PPO), poly(hydroxyethylmethacrylate) (PHEMA), poly(vinyl ether) (PVE), poly(vinyl methyl ether) (PVME), poly(vinyl butyl ether) (PVBE), polyimide and poly(dimethylsiloxane) (PDMS), and poly(N-isopropylacrylamide) (PNIPAM). In some embodiments, the coating 5250 may have a first diameter in an unhydrated (e.g., dry) state 5201 and may expand to a second diameter larger than the first diameter in a hydrated (e.g., wet) state 5202. In some embodiments, the second diameter may correspond to a diameter of the vessel such that the hydrogel element 5250 occludes the vessel (shown in FIG. 52B). In some embodiments, the first diameter may be between about 0.014 inches and about 0.027 inches, inclusive of all ranges and subranges therebetween and may swell to a diameter between about 0.040 inches and about 0.080 inches and have a length of between about 3 cm and about 25 cm, inclusive of all ranges and subranges therebetween. In some embodiments, the hydrogel element 5250 can swell to an occlusion diameter in the vessel in between about 1 minute and 10 minutes, inclusive of all ranges and subranges therebetween.

[0279] In some embodiments, the hemostatic device 5200 may include a proximal segment 5260 coupled to the carrier structure 5210 via a coupling mechanism 5626 (e.g., lock, mating mechanism) proximally for navigation. For example, the proximal segment 5260 may be configured to control translation (e.g., longitudinal bidirectional movement, push, pull) of the hemostatic device 5200 through a vessel such as shown in 5203-5205. For example, the proximal segment 5260 may comprise one or more of a hypotube, a single solid rod, a wire (e.g., a metallic wire comprised of stainless steel, nitinol, or nitinol alloy with one of more cross-sectional shapes including round, flat, square, diamond), a plurality of rods, a bundle, one or more tubes (with one or more lumens), a plurality of shaft strands, a cable (e.g., two or more wires running side by side, bonded, twisted or braided), a coil, a braid, a wire (e.g.,round, flat, square, diamond), combinations thereof, and the like. In some embodiments, the coupling mechanism 5626 may include a passive connection such as a hook, catch, press-fit, or screw type mechanism. In some embodiments, the coupling mechanism 5626 may be an active connection that requires an external force for decoupling such as a short burst of electrical energy.

[0280] In some embodiments, one or more of the coupling mechanism 5626 and a distal end 5263 of the hemostatic device 5200 may comprise one or more radiopaque materials such as platinum, iridium, gold, tungsten, and combinations thereof. In this manner, the coupling mechanism 5626 and / or distal end 5263 may serve as fiducials to indicate a relative location of the hemostatic device 5200 with respect to subject anatomy and a sheath 5270 (e.g., delivery catheter).

[0281] In some embodiments, the sheath 5270 may include a thin lubricious polymer such as, for example, high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), Nylon, or Polytetrafluoroethylene (PTFE). In some embodiments, the sheath 5270 may comprise a valve configured to transition a distal end of the sheath 5270 between a closed configuration and an open configuration, thereby controlling the flow of fluid into the distal end of the sheath 5270. This may prevent fluid from entering into a lumen of the sheath 5270 and prematurely transitioning the hemostatic device 5200 from an unhydrated configuration to a hydrated configuration. As shown in 5203, the hemostatic device 5200 in the unhydrated configuration may be advanced into a vessel 5214 and into a subdural space 5230 after the sheath 5270 transitions from the closed configuration to the open configuration. As shown in 5204, the sheath 5270 may be withdrawn relative to the hemostatic device 5200 and the coupling mechanism 5262 may uncouple (e.g., detach, release, seperate) the proximal segment 5260 from the carrier structure 5210. As shown in 5205, the sheath 5270 may be further withdrawn or retracted through the vessel 5214 and the carrier structure 5210 disposed within the vessel 5214, subdural space 5230, and transvascular opening therebetween may transition to a hydrated state where the larger diameter of the hydrated carrier structure 5210 occludes the vessel 5214.

[0282] In some embodiments, the hemostatic devices described herein can include distal features forming one or more of an anchoring mechanism and geometry configured forvisualization of the hemostatic device in an unconstrained configuration in the subdural space. FIG. 53 shows examples of hemostatic (e.g., occlusion, embolic) devices 5300-5305 having distal geometries (e.g., shapes, configurations) disposed in the subdural space. The geometry of the hemostatic device 5300-5305 may be configured to conform to a shape of the intradural, epidural, or intravascular corridor or vessel in which it is disposed when advanced distal to a sheath. A distal portion of the hemostatic devices 5300-5305 may comprise one or more fluoroscopic markers comprising one or more of platinum, iridium, tungsten of the carrier structure, and a coil. The geometry (e.g., shape) of the distal portion of the visualized hemostatic device may indicate that one or more of the vessel and perforation into the subdural space are occluded. For example, visualization of a coil shape corresponding to hemostatic device 5303 provides visual confirmation that the hemostatic device 5303 occludes the MMA and perforation between the MMA, dura, and subdural space. A distal portion of the hemostatic device may have a length between about 0.1 mm and about 30.0 mm, inclusive of all ranges and subranges therebetween. A distal portion of the hemostatic device may have a diameter between about 0.0001 inches and about 0.1000 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the distal portion of hemostatic device 5300 may comprise one or more tines (e.g., between about 2 tines and about 100 tines) that may splay when unconstrained in the subdural space. In some embodiments, the tines may be formed in a plane. In some embodiments, the tines may form a three-dimensional shape that splays (e.g., spreads) outward when unconstrained. In some embodiments, the tines can be constructed using a singular member that is cut using one or more of a laser, water ablation, and mechanical ablation. In some embodiments, the tines can be joined by one or more of a mechanical structure (e.g., sleeve, ring), adhesive, solder, and weld. In some embodiments, the tines may comprise one or more curves (e.g., device 5301). In some embodiments, the distal portion may comprise a three-dimensional spiral (e.g., device 5302). In some embodiments, the distal portion may comprise one or more of a planar spiral (e.g., device 5303), an S-shape (e.g., device 5304), and a curved shape (e.g., device 5305) having any of a V-shape, U-shape, and J-shape.

[0283] FIG. 54 shows X-ray images 5401-5404 of a perforated MMA 5430 (e.g., vessel) occluded via a hemostatic (e.g., occlusion, embolic) device 5400. In some embodiments, the hemostatic device 5400 can include a coil (e.g., packing coil, coil including a hydrogel sleeve). The hemostatic device 5400 may comprise a length between about 1.0 cm and about90 cm, inclusive of all ranges and subranges therebetween. The hemostatic device 5400 may comprise a diameter between about 0.010 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the coil may be configured to be advanced distal to a catheter and into a subdural space through a perforation 5440 in the MMA 5430. A distal portion 5410 of the coil may form an amorphous shape when in an unconstrained configuration in the subdural space, thereby indicating that the distal portion 5410 is in the subdural space when under visualization (e.g., fluoroscopic visualization). In some embodiments, the distal portion 5410 may be retracted into the MMA 5430 and / or the catheter such that the distal portion 5410 begins to transition from the unconstrained configuration shown in image 5401 towards a constrained (e.g., straight) configuration shown in image 5402 where the distal portion 5410 conforms to the shape of the MMA 5430. The straightening of the distal portion 5410 (e.g., coil) indicates that the distal portion of the hemostatic device 5430 is distal to the perforation 5440, whereas a proximal portion of the device 5430 is disposed within the MMA 5430 (e.g., perforated corridor, vessel). As shown in image 5403, the distal portion 5410 may be advanced into the subdural space such that the distal portion 5410 again transitions to the unconstrained configuration having an amorphous shape while a straightened portion of the hemostatic device 5430 is maintained in the MMA 5430, thereby forming a backstop 5420. As shown in image 5404, the hemostatic device 5400 can be retracted into a catheter 5460 as the catheter 5460 is retracted from the MMA 5430 such that the distal portion 5410 occludes 5450 the MMA 5430 by expanding (e.g., packing, breaking) in the MMA 5430 to occlude (e.g., completely) the perforation 5440 and a predetermined portion of the MMA 5430 proximal to the perforation 5440. In some embodiments, a proximal portion of the hemostatic device 5400 may be configured to expand (e.g., pack circumferentially) in one or more of the MMA 5430 and subdural space. In some embodiments, a length of the occlusion within a vessel (e.g., expanded portion of the hemostatic device 5400) may be between about 0.03 mm and about 3.00 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the hemostatic device 5400 may comprise a variable stiffness along a length of the hemostatic device 5400. For example, a distal portion of the hemostatic device (e.g., a distal 0.01 mm to about 1.00 mm portion) can be stiffer than a remaining length of the device, thereby providing a backbone for the device to provide support and / or force to promote packing or breaking of the device 5400 within the MMA 5430. In some embodiment, the hemostatic device 5400 may comprise a variable diameter along a length of the device 5400. For example, a diameter of a distal tip portion ofthe device 5400 (e.g., between about 0.01 mm and about 0.1 mm from the distal tip) can be between about 60% and about 90% of a diameter at the distal tip. In some embodiments, the diameter of the device 5400 may continue increasing with a ratio of between about 60% and 90% for every 0.01 mm to 0.1 mm down the length of the device 5400. In some embodiments, the embolic device 5400 may have a combination of differing stiffnesses and differing diameters along a length of the device 5400.Implantation

[0284] In some embodiments, the transvascular delivery system and / or an ancillary device used with the transvascular delivery system may be designed for long term implantation. Implantation may be required for diagnostic and therapeutic purposes, for example. In some embodiments, at least a portion of a catheter assembly can be implanted for delivery of pharmacological agents into the central nervous system and / or an electrode assembly can be implanted for sensing and / or recording. In some embodiments, a proximal end of the implanted catheter assembly may be coupled to a pump, a reservoir, and / or an injection port for delivery of the pharmacological agents. In some embodiments, a proximal end of the electrode assembly may be coupled to a pulse generator or wireless technology.

[0285] Embodiments for implantation may have one or more features configured to anchor a device assembly (e.g., catheter assembly, electrode assembly, implantable device) in a transvascular location, including expandable members (e.g., balloons, stents, baskets, coils) and deployable elements (e.g., fingers, ribs, fins). In some embodiments, the device assembly may be biased to form a predetermined three-dimensional (3D) shape. For example, the device assembly may have a preformed 3D shape prior to use and may elongate / straighten when constrained in one or more of a vessel, a delivery catheter (e.g., an outer shaft), and a guidewire or inner shaft in the lumen of the device assembly. When the guidewire or constraining outer / inner shaft is removed and / or when a pull wire is actuated, the device assembly may transition from a delivery configuration to an expanded configuration having a 3D (e.g., spiral) shape that results in radial expansion and facilitates anchoring to tissue (e.g., a surrounding vascular wall, bone). The anchoring features described herein may be configured to anchor a device assembly in one or more of an extravascular, transvascular, and intravascular position. For example, after gaining transvascular access to a subdural space, ananchor may be deployed (e.g., actuated, positioned), thereby fixating at least a portion of the device assembly, (e.g., implantable device) to the surrounding tissue.

[0286] In some embodiments, embolic agents may be delivered intravascularly to anchor the device assembly to the vessel and to ensure hemostasis. Embolization agents include, for example, cyanoacrylate glues, and / or ethylene vinyl-alcohol copolymers. In some embodiments, the embolization agents may be delivered by one or more lumens of a catheter assembly with side wall apertures oriented towards the vascular lumen (for example, trunk of the MMA) while the distal segment of the implant is in a transvascular position. For example, the side wall apertures may be substantially close to the transvascular access point in the segment of the device that remains intravascularly. In some methods of use, after gaining transvascular access and placing an implant in a predetermined location, embolic agents may be injected through the accessory lumen into the target vessel, resulting in a cast that surrounds the implant that anchors the implant to the vascular wall, and thereby prevents blood inflow and bleeding. In some embodiments, a cast of an embolization agent may be configured to surround between about 5 mm and about 50 mm of the device proximal to the perforation point, and between about 1 mm and about 20 mm of the vascular segment distal to the perforation point, inclusive of all ranges and subranges therebetween.

[0287] In some embodiments and methods of use, sclerosing agents including ethanol and sodium tetradecyl sulfate may be delivered to contract the artery around the implant resulting in anchoring and hemostasis.

[0288] In some embodiments, expandable substances including hydrogel polymer and gelatin may be included in the assembly design to expand intravascularly and through the perforation point resulting in anchoring and hemostasis.

[0289] In some embodiments, electrosurgery electrodes are included in the device assembly (e.g., catheter assembly and / or the electrode assembly) for electrocoagulation of the vasculature in monopolar or bipolar mode. In some methods of use, after gaining and maintaining transvascular access, electrosurgery energy may be delivered to the intravascular electrodes systems resulting in coagulation of proteins with vascular contraction and clot formation resulting in rapid anchoring and hemostasis.

[0290] In some embodiments, the hemostatic devices described herein can include distal features forming one or more of an anchoring mechanism and geometry configured for visualization of the hemostatic device in an unconstrained configuration in the subdural space. FIG. 53 shows examples of hemostatic (e.g., occlusion, embolic) devices 5300-5305 having distal geometries (e.g., shapes, configurations) disposed in the subdural space. The geometry of the hemostatic device 5300-5305 may be configured to conform to a shape of the intradural, epidural, or intravascular corridor or vessel in which it is disposed when advanced distal to a sheath. A distal portion of the hemostatic devices 5300-5305 may comprise one or more fluoroscopic markers comprising one or more of platinum, iridium, tungsten of the carrier structure, and a coil. The geometry (e.g., shape) of the distal portion of the visualized hemostatic device may indicate that one or more of the vessel and perforation into the subdural space are occluded. For example, visualization of a coil shape corresponding to hemostatic device 5303 provides visual confirmation that the hemostatic device 5303 occludes the MMA and perforation between the MMA, dura, and subdural space. A distal portion of the hemostatic device may have a length between about 0.1 mm and about 30.0 mm, inclusive of all ranges and subranges therebetween. A distal portion of the hemostatic device may have a diameter between about 0.0001 inches and about 0.1000 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the distal portion of hemostatic device 5300 may comprise one or more tines (e.g., between about 2 tines and about 100 tines) that may splay when unconstrained in the subdural space. In some embodiments, the tines may be formed in a plane. In some embodiments, the tines may form a three-dimensional shape that splays (e.g., spreads) outward when unconstrained. In some embodiments, the tines can be constructed using a singular member that is cut using one or more of a laser, water ablation, and mechanical ablation. In some embodiments, the tines can be joined by one or more of a mechanical structure (e.g., sleeve, ring), adhesive, solder, and weld. In some embodiments, the tines may comprise one or more curves (e.g., device 5301). In some embodiments, the distal portion may comprise a three-dimensional spiral (e.g., device 5302). In some embodiments, the distal portion may comprise one or more of a planar spiral (e.g., device 5303), an S-shape (e.g., device 5304), and a curved shape (e.g., device 5305) having any of a V-shape, U-shape, and J-shape.

[0291] FIG. 54 shows X-ray images 5401-5404 of a perforated MMA 5430 (e.g., vessel) occluded via a hemostatic (e.g., occlusion, embolic) device 5400. In some embodiments, thehemostatic device 5400 can include a coil (e.g., packing coil, coil including a hydrogel sleeve). The hemostatic device 5400 may comprise a length between about 1.0 cm and about 90 cm, inclusive of all ranges and subranges therebetween. The hemostatic device 5400 may comprise a diameter between about 0.010 inches and about 0.080 inches, inclusive of all ranges and subranges therebetween. In some embodiments, the coil may be configured to be advanced distal to a catheter and into a subdural space through a perforation 5440 in the MMA 5430. A distal portion 5410 of the coil may form an amorphous shape when in an unconstrained configuration in the subdural space, thereby indicating that the distal portion 5410 is in the subdural space when under visualization (e.g., fluoroscopic visualization). In some embodiments, the distal portion 5410 may be retracted into the MMA 5430 and / or the catheter such that the distal portion 5410 begins to transition from the unconstrained configuration shown in image 5401 towards a constrained (e.g., straight) configuration shown in image 5402 where the distal portion 5410 conforms to the shape of the MMA 5430. The straightening of the distal portion 5410 (e.g., coil) indicates that the distal portion of the hemostatic device 5430 is distal to the perforation 5440, whereas a proximal portion of the device 5430 is disposed within the MMA 5430 (e.g., perforated corridor, vessel). As shown in image 5403, the distal portion 5410 may be advanced into the subdural space such that the distal portion 5410 again transitions to the unconstrained configuration having an amorphous shape while a straightened portion of the hemostatic device 5430 is maintained in the MMA 5430, thereby forming a backstop 5420. As shown in image 5404, the hemostatic device 5400 can be retracted into a catheter 5460 as the catheter 5460 is retracted from the MMA 5430 such that the distal portion 5410 occludes 5450 the MMA 5430 by expanding (e.g., packing, breaking) in the MMA 5430 to occlude (e.g., completely) the perforation 5440 and a predetermined portion of the MMA 5430 proximal to the perforation 5440. In some embodiments, a proximal portion of the hemostatic device 5400 may be configured to expand (e.g., pack circumferentially) in one or more of the MMA 5430 and subdural space. In some embodiments, a length of the occlusion within a vessel (e.g., expanded portion of the hemostatic device 5400) may be between about 0.03 mm and about 3.00 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the hemostatic device 5400 may comprise a variable stiffness along a length of the hemostatic device 5400. For example, a distal portion of the hemostatic device (e.g., a distal 0.01 mm to about 1.00 mm portion) can be stiffer than a remaining length of the device, thereby providing a backbone for the device to provide support and / or force to promote packing or breaking of the device 5400 within theMMA 5430. In some embodiment, the hemostatic device 5400 may comprise a variable diameter along a length of the device 5400. For example, a diameter of a distal tip portion of the device 5400 (e.g., between about 0.01 mm and about 0.1 mm from the distal tip) can be between about 60% and about 90% of a diameter at the distal tip. In some embodiments, the diameter of the device 5400 may continue increasing with a ratio of between about 60% and 90% for every 0.01 mm to 0.1 mm down the length of the device 5400. In some embodiments, the embolic device 5400 may have a combination of differing stiffnesses and differing diameters along a length of the device 5400.

[0292] In some embodiments, one or more devices may be placed (e.g., implanted) in the extravascular space temporarily or permanently for long term monitoring and / or administration of therapy. For example, the devices may include one or more electrodes, sensors, transmitter, receivers, grids, ports, catheters, biopsy needles or punches, implantable chemotherapy wafers or radiation seeds, combinations thereof, and the like. In some embodiments, an apparatus may comprise an elongate body (e.g., catheter) defining a lumen, the elongate body including a distal end configured to be advanced through an intracranial vessel and into an intracranial extravascular space over a shaft. The elongate body may further include a proximal end configured to be coupled to a source of therapy such that the therapy can be delivered to the intracranial extravascular space via the catheter. An anchor may be coupled to the elongate body and configured to expand to releasably anchor the elongate body to tissue. In some embodiments, the intracranial vessel may be the middle meningeal artery. In some embodiments, the shaft may comprise a perforating device that is configured to perforate a wall of the intracranial vessel to form a passageway into the intracranial extravascular space, the elongate body being configured to be advanced over the shaft and through the passageway into the intracranial extravascular space. In some embodiments, a sensor may be configured to monitor a state of the elongate body or a condition within the intracranial extravascular space.

[0293] FIG. 59 is a schematic cross-sectional side view 5900 of an indwelling catheter 5940 in a head 5910 of a subject. For example, the indwelling catheter 5940 may be disposed in a subdural space 5930 for a predetermined length of time (e.g., days, weeks). In some embodiments, the indwelling catheter 5940 may be advanced through the MMA 5920 at the base of the skull 55910 into the subdural compartment and exit one of an maxillary artery and an external carotid artery (ECA) where it will tunnel under the skin (e.g., based on ultrasoundguidance) and connect to an implantable infusion pump 5950 or injection port, for example, below the clavicle. The indwelling catheter 5490 may be configured to deliver (e.g., infuse) a therapy (e.g., liquid, drug). The indwelling catheter 5490 can be configured to measure or monitor one or more parameters, e.g., via sensors as described herein. For example, the indwelling catheter 5490 can be configured to monitor pressure, temperature, or other conditions within the extravascular space. Additionally or alternatively, the indwelling catheter 5940 may comprise an anchor and configured to be internally anchored to tissue (e.g., FIG. 56) as described herein to prevent the indwelling catheter 5940 from migrating from a predetermined position over time. In some embodiment, the anchor may be releasably coupled (e.g., loosened, collapsed) to tissue to facilitate removal of the indwelling catheter 5490 from the body.Sensors

[0294] In some embodiments, one or more sensors 540 may be coupled to one or more of a catheter 510, a perforating device 520, and a hemostatic device 530. Sensors 540 may be configured to measure one or more parameters including, but not limited to, pressure and impedance. The sensor measurements may be used by one or more of an operator and signal generator during a procedure. For example, pressure measurements may indicate to the operator the location and / or orientation (e.g., a state) of a perforating device 520 of the catheter assembly 502 while RF energy may be delivered to a perforating element 524 only when a measured impedance is within a predetermined range so as to prevent damage to brain tissue.

[0295] In some embodiments, a pressure sensor may be configured to capture pressure measurements at a distal end of the perforating device to monitor a location or state of the perforating device. In some embodiments, a pressure sensor may comprise one or more of a potentiometric pressure sensor, an inductive pressure sensor, a capacitive pressure sensor, a strain gauge pressure sensor, a fiber optic pressure sensor, a variable reluctance pressure sensor, a micro-electromechanical system pressure sensor, and a piezoelectric pressure sensor. For example, a piezoelectric pressure sensor may include a piezoelectric film disposed along an outer diameter of a perforating element in proximity to the distal end. The measured signal may include a peak pressure value associated with penetration through the MMA wall followed by a pressure drop associated with access to the subdural space. In someembodiments, a pressure sensor may be configured to measure a pressure waveform (e.g., arterial, intracranial, or venous perforation waveforms) upon penetration from the vascular lumen into the intracranial compartment. In some embodiments, tissue spectroscopy values may be measured to monitor perforation and access into the subdural space.

[0296] In some embodiments, a first pressure sensor may be disposed at or adjacent a distal end of the perforating element and configured to measure pressure against tissue and / or fluid. A second pressure sensor may be disposed proximal to the first pressure sensor (e.g., about 0.2 mm and about 2 mm from the first pressure sensor). First and second pressure sensor measurements when the perforating element is advanced through a blood vessel correspond to the nominal blood pressure. When the perforating element contacts a wall of a blood vessel, the first pressure sensor measurement corresponding to the vessel wall may be higher than the second pressure measurement corresponding to the blood pressure. During tissue perforation, the first pressure sensor measurement may be lower than the second pressure measurement. After formation of an opening in the vessel wall, the first and second pressure measurements may correspond to the fluid pressure of the subdural space.

[0297] In some embodiments, an impedance sensor may be configured to measure impedance, permittivity, and / or conductivity) of tissue and fluid to monitor perforation and access into the subdural space. Changes in impedance (or other dielectric property) between an artery, dura, fluid (e.g., contrast fluid, cerebrospinal fluid, subdural hematoma), intradural space, and the brain may indicate the location and of the perforating element throughout a procedure. Impedance measurements may be used to control energy delivery by the signal generator. For example, energy delivery may be modified to optimize ablation and be stopped based on the measured impedance.

[0298] In some embodiments, a temperature sensor may be configured to measure a temperature of tissue and fluid. For example, the temperature sensor may include a thermocouple disposed at or adjacent a distal end of the perforating element. The measured temperature may be used to control waveform delivery (e.g., impedance, voltage, duty cycle, pulse width) by the signal generator. For example, energy delivery may be modified to optimize and ablation and stopped if the measured temperature exceeds a predetermined threshold in order to prevent unintended tissue damage.

[0299] In some embodiments, the perforating element 524 (e.g., electrode) may be configured to measure an electroencephalographic (EEG) signal disposed within about 20 mm from a distal end of the perforating element 524. The perforating element 524 may be configured to alternately deliver RF energy and measure an EEG signal, impedance signa, and the like.

[0300] In some embodiments, a force sensor disposed on or adjacent a perforating element may be configured to measure a force associated with penetration of the perforating device through the MMA and dura. For example, pressure may be measured using a pressure transducer disposed outside the subject.

[0301] In some embodiments, a catheter assembly 5500 (e.g., catheter, guidewire, perforation element, etc.) may include a pressure sensor 5530, as shown in FIG. 55. The pressure sensor 5530 can be configured to measure a pressure in the subdural space during injection or aspiration to prevent brain atrophy during therapy. For example, the pressure sensor 5530 may include one or more of an optical fiber 5510 and a microelectromechanical sensor (MEMS) 5520. In some embodiments, the optical fiber 5510 may be configured to measure a change in light intensity to estimate intracranial pressure. For example, an increase in pressure may correspond to a source of light being progressively blocked through a window of the optical fiber 5510. Therefore, the pressure sensor measuring lower light levels may indicate a higher pressure in the subdural space. In some embodiments, the catheter assembly may include a plurality of optical fibers (e.g., between about 2 optical fibers and about 6 optical fibers) in a sidewall of the assembly 5500 that measures a distance therebetween and in turn may be used to estimate a pressure based on the measured distance. In some embodiments, the fiberoptic sensor 5530 can have a diameter between about 0.25 microns and about 500 microns, inclusive of all ranges and subranges therebetween. In some embodiments, the pressure sensor 5530 can be located within about 5 cm or less from a distal end of the catheter assembly 5500. In some embodiments a MEMS sensor 5520 can be disposed near a distal end of the catheter assembly (e.g., catheter, guidewire, perforation element). In some embodiments, the MEMS sensor 5520 can be disposed in the distal 5 cm of the catheter assembly 5500. In some embodiments, the MEMS sensor 5520 can have a size of between about 100 microns and about 500 microns, inclusive of all ranges and subranges therebetween. In some embodiments, the MEMS sensor 5520 can change in capacitance as micro sized plates within the sensor 5520 tilt, compress, and relax in response to an externalforce (e.g., pressure in the subdural space). The sensor 5520 may include a connector (e.g. fiberoptic or electrical wire) that extends through a predetermined length of the catheter assembly 5500. In some embodiments, the connector of the pressure sensor 5520 may be configured to connect to a user-interface configured to display the pressure of the subdural space measured by the pressure sensor to a user.Vacuum Source

[0302] In some embodiments, the vacuum source 550 may be coupled to a proximal portion 513 of the catheter 510 (e.g., elongate body). The vacuum source 550 may be configured to provide negative pressure (e.g., suction) to a lumen of the catheter 510. The suction generated by the vacuum source 550 may be configured to remove fluid and matter (e.g., from a subdural hematoma) through the lumen of the catheter 510. In some embodiments, the vacuum source may include one or more of a pump and syringe. The vacuum source 550 may be configured to operate in one or more modes including continuous, dynamic, cyclical, pulsatile, low frequency, high frequency, combinations thereof, and the like.Signal Generator

[0303] Generally, the signal generators described here may be configured to provide energy (e.g., energy waveforms) to a perforating element to form an opening in tissue. In some embodiments, the signal generator 560 may be coupled to one or more of the perforating device 520 and the hemostatic device 530. In particular, the signal generator 560 may be configured to generate energy for delivery using the perforating element 524 of the distal tip portion 522. The signal generator 560 may include a processor 562, a memory 564, and an input / output device 566 configured to control the signal generator 560 and provide appropriate energy waveforms for tissue ablation and to ensure subject safety. In some embodiments, the signal generator may be configured to control waveform generation and delivery in response to received sensor data. For example, energy delivery may be inhibited unless an impedance sensor measurement confirms a tissue type to be ablated.

[0304] The signal generator may generate and deliver several types of signals including, but not limited to, RF, pulsed field ablation, microwave, diathermy, laser, electrosurgical, and electrocautery. For example, diathermy, laser, and electrocautery waveforms may be used toablate, cauterize, and / or coagulate one or more of a vessel, the membranes surrounding the subdural hematoma, the septations inside the hematoma, and any bleeding source. Diathermy, laser and electrocautery waveforms may also be used to occlude or close the transvascular passageway and a vascular lumen such as the MMA.

[0305] In some embodiments, the signal generator may be configured in a monopolar configuration or a bipolar configuration. For example, the signal generator may generate monophasic (DC) pulses and biphasic (DC and AC) pulses. The monopolar configuration may comprise an external grounding pad attached to the body to close the electrical circuit. The bipolar configuration may comprise a return wire coupled to the signal generator without a grounding pad. In some embodiments, electrosurgery using the systems described herein may be performed in a monopolar configuration and a cut mode configured to deliver high density RF energy localized to the perforating element 524 (e.g., cutting electrode). Electrosurgery performed in a bipolar configuration may be configured to deliver RF energy between a first electrode (e.g., RF supply) and a second electrode (e.g., RF return) or ground, such that energy density depends on a distance between the first and second electrodes. In some embodiments, electrocautery or coagulation using the systems described herein may be performed in a coagulation mode using either a monopolar or bipolar configuration. The bipolar configuration may enable control of perforation characteristics (e.g., temperature) based on the energy waveform, length of coagulation, and distance between the first and second electrodes.

[0306] The signal generator may comprise a processor, memory, energy source, and user interface. The processor may incorporate data received from one or more of memory, energy source, user interface, and catheter assembly. The memory may further store instructions to cause the processor to execute modules, processes and / or functions associated with the system, such as waveform generation and delivery. For example, the memory may be configured to store subject data, clinical data, procedure data, and the like. In some embodiments, the signal generator may be configured to generate a waveform in a range between about 250 kHz and about 750 kHz, and about 120 V and about 400 V, inclusive of all ranges and subranges therebetween. In some embodiments, the signal generator may be configured to generate an ablation waveform (e.g., cutting waveform) in a range between about 1W and about 300W, inclusive of all ranges and subranges therebetween. For example, a transvascular opening between a lumen of an MMA and a subdural space may be formed bythe signal generator generating an ablation waveform including a power of between about 15 W and about 60 W, a duty cycle of at least about 300 ms, and for a duration of less than about 5 seconds, inclusive of all ranges and subranges therebetween. For example, the ablation waveform may be generated for less than about 2 seconds.

[0307] Generally, the processor (e.g., CPU) described here may process data and / or other signals to control one or more components of the system. The processor may be configured to receive, process, compile, compute, store, access, read, write, and / or transmit data and / or other signals. In some embodiments, the processor may be configured to access or receive data and / or other signals from one or more of a sensor (e.g., impedance sensor, pressure sensor) and a storage medium (e.g., memory, flash drive, memory card). In some embodiments, the processor may be any suitable processing device configured to run and / or execute a set of instructions or code and may include one or more data processors, image processors, graphics processing units (GPU), physics processing units, digital signal processors (DSP), analog signal processors, mixed-signal processors, machine learning processors, deep learning processors, finite state machines (FSM), compression processors (e.g., data compression to reduce data rate and / or memory requirements), encryption processors (e.g., for secure wireless data and / or power transfer), and / or central processing units (CPU). The processor may be, for example, a general purpose processor, Field Programmable Gate Array (FPGA), an Application Specific Integrated Circuit (ASIC), a processor board, and / or the like. The processor may be configured to run and / or execute application processes and / or other modules, processes and / or functions associated with the system. The underlying device technologies may be provided in a variety of component types (e.g., metal-oxide semiconductor field-effect transistor (MOSFET) technologies like complementary metal-oxide semiconductor (CMOS), bipolar technologies like emitter- coupled logic (ECL), polymer technologies (e.g., silicon-conjugated polymer and metal- conjugated polymer-metal structures), mixed analog and digital, and the like.

[0308] The systems, devices, and / or methods described herein may be performed by software (executed on hardware), hardware, or a combination thereof. Hardware modules may include, for example, a general-purpose processor (or microprocessor or microcontroller), a field programmable gate array (FPGA), and / or an application specific integrated circuit (ASIC). Software modules (executed on hardware) may be expressed in a variety of software languages (e.g., computer code), including C, C++, Java®, Python, Ruby,Visual Basic®, and / or other object-oriented, procedural, or other programming language and development tools. Examples of computer code include, but are not limited to, micro-code or micro-instructions, machine instructions, such as produced by a compiler, code used to produce a web service, and files containing higher-level instructions that are executed by a computer using an interpreter. Additional examples of computer code include, but are not limited to, control signals, encrypted code, and compressed code.

[0309] Generally, the ablation device described here may comprise a memory configured to store data and / or information. In some embodiments, the memory may comprise one or more of a random access memory (RAM), static RAM (SRAM), dynamic RAM (DRAM), a memory buffer, an erasable programmable read-only memory (EPROM), an electrically erasable read-only memory (EEPROM), a read-only memory (ROM), flash memory, volatile memory, non-volatile memory, combinations thereof, and the like. In some embodiments, the memory may store instructions to cause the processor to execute modules, processes, and / or functions such as signal waveform generation, system control, data and / or signal transmission, data and / or signal reception, and / or communication. Some embodiments described herein may relate to a computer storage product with a non-transitory computer- readable medium (also may be referred to as a non-transitory processor-readable medium) having instructions or computer code thereon for performing various computer-implemented operations. The computer-readable medium (or processor-readable medium) is non-transitory in the sense that it does not include transitory propagating signals per se (e.g., a propagating electromagnetic wave carrying information on a transmission medium such as space or a cable). The media and computer code (also may be referred to as code or algorithm) may be those designed and constructed for the specific purpose or purposes.

[0310] In some embodiments, the system may further comprise a communication device configured to permit an operator to control the system. The communication device may comprise a network interface configured to connect the system to another system (e.g., Internet, remote server, database) by wired or wireless connection. In some embodiments, the system may be in communication with other devices (e.g., cell phone, tablet, computer, smart watch, and the like) via one or more wired and / or wireless networks. In some embodiments, the network interface may comprise one or more of a RF receiver / transmitter, an optical (e.g., infrared) receiver / transmitter, and the like, configured to communicate with one or moredevices and / or networks. The network interface may communicate by wires and / or wirelessly with one or more of the system, network, database, and server.

[0311] The network interface may comprise RF circuitry configured to receive and / or transmit RF signals. The RF circuitry may convert electrical signals to / from electromagnetic signals and communicate with communications networks and other communications devices via the electromagnetic signals. The RF circuitry may comprise well-known circuitry for performing these functions, including but not limited to an antenna system, an RF transceiver, one or more amplifiers, a tuner, one or more oscillators, a mixer, a digital signal processor, a CODEC chipset, a subscriber identity module (SIM) card, memory, and so forth.

[0312] Wireless communication through any of the devices may use any of plurality of communication standards, protocols and technologies, including but not limited to, Global System for Mobile Communications (GSM), Enhanced Data GSM Environment (EDGE), high-speed downlink packet access (HSDPA), high-speed uplink packet access (HSUPA), Evolution, Data-Only (EV-DO), HSPA, HSPA+, Dual-Cell HSPA (DC-HSPDA), long term evolution (LTE), near field communication (NFC), wideband code division multiple access (W-CDMA), code division multiple access (CDMA), time division multiple access (TDMA), Bluetooth, Wireless Fidelity (WiFi) (e.g., IEEE 802. I la, IEEE 802.1 lb, IEEE 802.11g, IEEE 802.1 In, and the like), voice over Internet Protocol (VoIP), Wi-MAX, a protocol for e-mail (e.g., Internet message access protocol (IMAP) and / or post office protocol (POP)), instant messaging (e.g., extensible messaging and presence protocol (XMPP), Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions (SIMPLE), Instant Messaging and Presence Service (IMPS)), and / or Short Message Service (SMS), or any other suitable communication protocol. In some embodiments, the devices herein may directly communicate with each other without transmitting data through a network (e.g., through NFC, Bluetooth, WiFi, RFID, and the like).

[0313] In some embodiments, the input device (e.g., keyboard, buttons, touch screen) and output device (e.g., display device) may be configured to receive input data from one or more of the system, network, database, and server. For example, operator control of an input device (e.g., keyboard, buttons, touch screen) may be received by the input / output device and may then be processed by processor and memory for the user interface to output a control signal to the system. Some embodiments of an input device may comprise at least one switchconfigured to generate a control signal. For example, an input device may comprise a touch surface for an operator to provide input (e.g., finger contact to the touch surface) corresponding to a control signal. An input device comprising a touch surface may be configured to detect contact and movement on the touch surface using any of a plurality of touch sensitivity technologies including capacitive, resistive, infrared, optical imaging, dispersive signal, acoustic pulse recognition, and surface acoustic wave technologies. In embodiments of an input device comprising at least one switch, a switch may comprise, for example, at least one of a button (e.g., hard key, soft key), touch surface, keyboard, analog stick (e.g., joystick), directional pad, mouse, trackball, jog dial, step switch, rocker switch, pointer device (e.g., stylus), motion sensor, image sensor, and microphone. A motion sensor may receive operator movement data from an optical sensor and classify an operator gesture as a control signal. A microphone may receive audio data and recognize an operator voice as a control signal.

[0314] A haptic device may be incorporated into one or more of the input and output devices to provide additional sensory output (e.g., force feedback) to the operator. For example, a haptic device may generate a tactile response (e.g., vibration) to confirm operator input to an input device (e.g., touch surface). As another example, haptic feedback may notify that operator input is overridden by the system.Visualization Device

[0315] In some embodiments, the visualization device 570 may be configured to visualize (e.g., generate one or more images) corresponding to one or more components of the catheter assembly 502 (e.g., catheter 510, perforating device 520, hemostatic device 530) disposed within the subject. As described in more detail herein, the visualization device 570 may facilitate positioning of the catheter assembly 502 within the intravascular and extravascular spaces of the subject (e.g., orientation and placement of the distal tip portion 522 and perforating element 524 relative to the blood vessel).

[0316] In some embodiments described herein, one or more elements of the catheter assembly 502 (e.g., catheter 510, perforating device 520, hemostatic device 530) may include a set of fiducials (e.g., radiopaque elements) spaced along a length of the catheter assembly 502 (e.g., catheter 510, perforating device 520) and configured to be imaged by thevisualization device. For example, the set of fiducials may include radiopaque fluoroscopic markers (FM).

[0317] In some embodiments, a radiopaque element may include one or more of gold, platinum, platinum iridium, tantalum, bismuth, tungsten-filled polymers, combinations thereof, and the like. In some embodiments, a fiducial may be disposed at proximal end of a perforating element 524 to indicate a relative location of a distal end of the perforating element 524. In some embodiments, a fiducial may be configured to indicate rotational orientation.

[0318] For example, visualization may include one or more of optical coherence tomography (OCT) and intravascular ultrasound (IVUS) tomography. With respect to IVUS, dura, dural appendages, cerebrospinal fluid, brain superficial pia mater, cortical gray matter, and white matter are hyperechoic. The subarachnoid space contains numerous vessels visible on a Doppler mode of ultrasound. The subdural collection may have hyperechoic membranes, and may be hyperechoic, hypoechoic, or a combination thereof.

[0319] In some embodiments, visualization may include a combination of invasive (e.g., US, CTO, angioscopy) and non-invasive (fluoroscopy, US, CT, MR) imaging modalities. In some embodiments, the catheter 510 may include an optical sensor (e.g., camera) and / or light source for endoscopic visualization of one or more of catheter advancement in a subdural or epidural space, and transvascular drainage of subdural collection. In some embodiments, the optical sensor may include one or more of an optical fiber, a complementary-symmetry metal-oxide-semiconductor, a scanning fiber endoscope, combinations thereof, and the like.

[0320] In some embodiments, the system 500 may include one or more magnets configured to provide one or more of directionality, penetration, and navigation. For example, a catheter assembly 502 may comprise a first magnet and an external source configured to be placed on an outer surface of the head may comprise a second magnet, where the first and second magnets may be configured to provide one or more of directionality, penetration, and navigation. In some embodiments, the magnet may be a permanent magnet, temporary magnet, and / or electromagnetic. In some embodiments, the magnet may be composed of one or more of neodymium, samarium cobalt, platinum-cobalt, alnico, ceramic, and ferrite.

[0321] In some embodiments, different components of the catheter assembly 502 (e.g., catheter 510, perforating device 520, hemostatic device 530) can be configured to be manipulated / actuated in different degrees of freedom, e.g., allowing for further maneuverability or steering of the catheter assembly within vasculature or positioning of components thereof within the vasculature or extravascular space (e.g., subdural space).Biopsy Device

[0322] In some embodiments, a catheter and / or a catheter assembly may comprise a tissue treatment device such as a biopsy device. FIG. 35 A is a schematic side view of a catheter 3500, 3502, 3504 configured to perform a tissue (e.g., brain) biopsy. In some embodiments, the catheter 3500, 3502, 3504 may comprise a biocompatible material such as stainless steel, nitinol, platinum, tungsten, combinations thereof, and the like. For example, a distal portion of the catheter 3500, 3502, 3504 may comprise one or more of stainless steel, nitinol, nitinol alloy, cobalt chromium, and combinations thereof.

[0323] In some embodiments, the catheters 3500, 3502, 3504 may each include an opening disposed along a sidewall of the catheter 3500, 3502, 3504. The catheter 3500 can be, for example, a catheter device or hypotube, as described herein. The catheters 3502, 3504 can be, for example, a distal catheter segment or hypotube coupled to a push / pull wire or hypotube having a smaller diameter than the distal catheter segment or hypotube, as described herein. In some embodiments, the catheters 3500, 3502, 3504 can have an outer diameter that ranges between about 0.017 inches and about 0.048 inches, inclusive of all ranges and values therebetween, and / or an inner diameter between about 0.010 inches and about 0.044 inches, inclusive of all ranges and values therebetween. In some embodiments, the catheters 3500, 3502, 3504 may each include an opening 3510 disposed along a sidewall of the catheter 3500, 3502, 3504. For example, a distance between a distal end of the catheter and the opening may be between about 3 mm and about 5 mm, between about 3 mm and about 4 mm, between about 4 mm and about 5 mm, and between about 2.5 mm and about 3.5 mm, inclusive of all ranges and subranges therebetween. In some embodiments, the opening 3510 may comprise an arc length of between about 30 degrees and about 180 degrees, between about 30 degrees and about 105 degrees, between about 105 degrees and about 180 degrees, and between about 60 degrees and about 150 degrees, inclusive of all ranges and subranges therebetween. In some embodiments, the opening 3510 may comprise a length of betweenabout 1 mm and about 20 mm, between about 1 mm and about 10 mm, between about 10 mm and about 20 mm, and between about 5 mm and about 15 mm, inclusive of all ranges and subranges therebetween. In some embodiments, one or more edges of the opening 3510 and one or more edges of a distal opening of a second catheter 3530 may comprise one or more cutting features configured to facilitate one or more of tissue cutting, tissue capture, and tissue removal. In some embodiments, the catheter 3500, 3502, 3504 may comprise a first lumen configured to receive and hold tissue (e.g., brain tissue). For example, a distal portion of a lumen of the catheter 3500, 3502, 3504 may be configured to receive and hold captured brain tissue. In some embodiments, the catheter 3500, 3502, 3504 may comprise a second lumen configured to provide irrigation (e.g., saline flush) to assist one or more of tissue capture and removal. For example, a first lumen may have a first diameter and a second lumen may have a second diameter smaller than the first diameter. The second lumen may be disposed along a sidewall of the catheter 3500, 3502, 3504 generally opposite the opening 3510. In some embodiments, fluid irrigation from the second lumen into the first lumen may aid tissue capture and advance tissue proximally through the catheter 3500, 3502, 3504. For example, a distal tip of the first lumen may be irrigated via the second lumen so as to apply fluid pressure to the tissue in the first lumen and push the tissue proximally through the catheter 3500, 3502, 3504.

[0324] In some embodiments, the catheters 3500, 3502, 3504 may each include one or more fiducials 3520 corresponding to any of the fiducials described herein. For example, the fiducials 3520 may be configured to confirm a location and orientation of the opening 3510. For example, the fiducials 3520 may be configured to confirm a position and orientation of the catheter 3430 relative to the brain. In some embodiments, the fiducial 3520 may have a shape comprising one or more of a T-shape, an O-shape, a U-shape, a J-shape, an H-shape, an L-shape, and a geometric shape including one or more of a triangle, a square, a circle, an ellipsoid, a polygon, combinations thereof, and the like.

[0325] In some embodiments, the catheter assembly may include a biopsy device (e.g., catheter 3500, 3502, 3504) disposed within a second catheter 3530 corresponding to any of the catheters described herein (e.g., catheter 510, elongate body). The catheter 3500, 3502, 3504 may be a first catheter. For example, the second catheter 3530 may comprise one or more of an inner layer of PTFE, a braid, a coil, a combination of a braid and a coil, an outer layer of polymer having varying material stiffness (e.g., softer distal portion, stiffer proximalportion), and accelerants for lubricity. In some embodiments, the second catheter 3530 may include one or more additional lumens with one or more distal apertures. The additional lumens may have a diameter of between about 0.003 inches and about 0.018 inches, and can be in fluid communication with an exterior of the second catheter 3530. The apertures can be designed to be in the transvascular segment of the catheter during expected use, or to remain in the intravascular space while the main lumen aperture is disposed in the extravascular space. Transvascular apertures can be configured for delivery of agents or substances to the intradural compartment. Intravascular apertures may be configured for controlling perforation, providing stability to the catheter, and / or delivery of embolization agents. Intravascular apertures of the additional lumens may be located on a sidewall of a distal portion of the second catheter 3530, at a distance of between about 5 mm and about 50 mm from the catheter tip, inclusive of all ranges and values therebetween. In some embodiments, an additional lumen with a sidewall aperture can be beneficial to control the depth of perforation intradurally when a wire is disposed in the lumen of the MMA during transvascular catheter advancement. This assembly (transvascular catheter and intravascular wire emerging from the catheter by sidewall aperture) can also improve the spatial stability of the assembly during transvascular procedures. The additional lumen with an intravascular aperture while the main lumen aperture is transvascular enables the delivery of other devices or therapeutic agents, including embolization material for arteriotomy and arterial occlusion while the catheter is in a transvascular position.

[0326] FIGS. 35B and 35C are schematic cross-sectional side views of a catheter assembly in a head of a subject. For example, a second catheter 3530 comprising one or more fiducials 3532 may be disposed within a vessel 3550 (e.g., MMA) and configured to advance through the dura 3560 at the foramen spinosum of the skull 3540 and into a subdural space including the brain 3570. FIG. 35B depicts a perforating device 3500 (e.g., biopsy device) disposed within the second catheter 3530 and configured to be advanced beyond a distal end of the second catheter 3530 and into the brain 3570. Negative pressure may be applied to a lumen of the perforating device 3500 to suction 3580 tissue (e.g., brain tissue 3570) into the opening 3510 of the perforating device 3500. Once the tissue is captured under vacuum inside the lumen of the perforating device 3500, the perforating device 3500 may be withdrawn 3590 into the second catheter 3530 and subsequently withdrawn from the body, as shown in FIG. 35B. The retraction of the perforating device 3500 relative to the second catheter 3530 willcut tissue disposed around the opening 3510 of the perforating device 3500 using one or more of the edges of the opening 3510 and a distal end of the second catheter 3530. In some embodiments, after withdrawing the perforating device 3500 from the vessel 3550, the second catheter 3530 may be maintained in the transvascular opening between the vessel 3550 and subdural space to reduce bleeding and facilitate the introduction of a hemostatic device configured to close the opening.

[0327] In some embodiments, the catheter assembly may correspond to a biopsy device comprising a plurality of catheters configured to rotate relative to each other. FIGS. 36A-36D are schematic side and cross-sectional top views of a catheter assembly 3630 including a first catheter 3610 (e.g., outer catheter) and a second catheter 3620 (e.g., inner catheter). The first catheter 3610 may comprise a first opening 3612 and a first lumen fluidically coupled to the first opening 3612. The second catheter 3620 may comprise a second opening 3622 and a second lumen fluidically coupled to the second opening 3622. The second catheter 3620 may be configured to be disposed within the first lumen of the first catheter 3610 and configured to translate relative to the first catheter 3610. In some embodiments, one or more edges of the first and second openings 3612, 3622 may comprise one or more cutting features configured to facilitate one or more of tissue cutting, tissue capture, and tissue removal.

[0328] In some embodiments, the first catheter 3610 may further comprise one or more fiducials 3614 (e.g., radiopaque markers) configured to aid positioning of the catheter 3610 within a vessel. For example, a distal portion of the catheter 3610 may include a first fiducial distal to the first opening 3614 and a second fiducial proximal to the first opening 3614. Similarly, the second catheter 3620 may comprise one or more fiducials 3624 such as a first fiducial distal to the second opening 3622 and a second fiducial proximal to the second opening 3624. The position of the fiducials 3614, 3624 relative to each other may indicate, for example, the location of the first and second openings 3612, 3622 within the body (e.g., within the brain).

[0329] In some embodiments, as shown in FIG. 36B, one or more of the openings 3612, 3622 and fiducials 3614, 3624 may be aligned (e.g., overlapping) when the distal ends of the first and second catheters 3610, 3620 are aligned. In some embodiments, the catheter assembly 3630 may be advanced through a perforation point (e.g., wall of the MMA, dura) and into a subdural space. The catheter assembly 3630 may be inserted into tissue (e.g.,brain) in an open configuration (e.g., FIG. 36B) where the first opening 3614 and the second opening 3622 overlap to provide an aperture for receiving tissue into the second lumen of the second catheter 3620. In some embodiments, negative pressure may be applied through the second lumen to suction 3632 brain tissue into the second lumen of the catheter assembly 3630. After a predetermined amount of tissue is suctioned into the catheter assembly 3630, the second catheter 3620 may be rotated 3634 relative to the first catheter 3620 (or vice versa), as shown in FIG. 36C, thereby cutting the brain tissue within and closing the opening between the second lumen and the subdural space. One or more of the first catheter 3610 and the second catheter 3620 may be withdrawn 3636 from the body. For example, FIG. 36D depicts the second catheter 3620 retracted proximally through the first lumen of the first catheter 3610.

[0330] FIGS. 37A-37D are schematic side and cross-sectional top views of catheter assemblies 3700 including a first catheter 3710 and a second catheter 3720. For example, the second catheter 3720 may be disposed within a lumen of the first catheter 3710. The first catheter 3710 may comprise a first opening 3712 and a first lumen fluidically coupled to the first opening 3712. The second catheter 3720 may comprise a second opening 3722 and a second lumen fluidically coupled to the second opening 3722. The second catheter 3720 may be configured to be disposed within the first lumen of the first catheter 3710 and configured to translate relative to the first catheter 3710. In some embodiments, one or more edges of the first and second openings 3712, 3722 may comprise one or more cutting features configured to facilitate one or more of tissue cutting, tissue capture, and tissue removal.

[0331] In some embodiments, the first catheter 3710 may further comprise one or more fiducials 3714, 3716 (e.g., radiopaque markers) configured to aid positioning of the catheter 3710 within a vessel. For example, a distal portion of the catheter 3710 may include a first fiducial 3714 distal to the first opening 3714, a second fiducial 3716 proximal to the first opening 3714 (FIG. 37A), and a third and fourth fiducials 3716 disposed lengthwise parallel and on opposite sides of the first opening 3714 (FIG. 37C). Similarly, the second catheter 3720 may comprise one or more fiducials 3724 such as a first fiducial distal to the second opening 3722, a second fiducial proximal to the second opening 3724, and a third and fourth fiducials 3726 disposed lengthwise parallel and on opposite sides of the second opening 3724. Additionally or alternatively, FIG. 37D depicts third and fourth fiducials 3716, 3726 disposed on a sidewall opposite the respective openings 3712, 3722. The position of thefiducials 3714, 3716, 3724, 3726 relative to each other may indicate, for example, the location of the first and second openings 3712, 3722 within the body (e.g., brain). The fiducials 3714, 3716, 3724, 3726 may comprise a predetermined length and arc length.

[0332] In some embodiments, as shown in FIG. 37B, one or more of the openings 3712, 3722 and fiducials 3714, 3716, 3724, 3726 may be aligned (e.g., overlapping) when the distal ends of the first and second catheters 3710, 3720 are aligned. For example, the openings 3712, 3722 may align (e.g., overlap) and be configured to receive tissue when the fiducials 3714, 3724 overlap and face the same circumferential side as shown in the top view of FIG. 37A corresponding to an anterior-posterior (AP) fluoroscopic view. Similarly, the openings 3712, 3722 may align 3742 when fiducials 3716, 3726 overlap as shown in the top view of FIG. 37C. Additionally or alternatively, the openings 3712, 3722 may be aligned (e.g., overlap) when the fiducials 3714, 3722 are aligned but on opposite circumferential sides.

[0333] In some embodiments, the catheter assembly 3730 may be advanced through a perforation point (e.g., wall of the MMA, dura) and into a subdural space. The catheter assembly 3730 may be inserted into tissue (e.g., brain) in an open configuration where the first opening 3712 and the second opening 3722 are aligned 3740 (e.g., overlap) to provide an aperture for receiving tissue into the second lumen. In some embodiments, negative pressure may be applied through the second lumen to suction tissue (e.g., brain tissue) into the second lumen of the catheter assembly 3730. After a predetermined amount of tissue is suctioned into the catheter assembly 3730, the second catheter 3720 may be rotated 3744, 3746 relative to the first catheter 3720 (or vice versa), as shown in FIGS. 37B and 37D, thereby cutting the tissue within and closing the opening between the second lumen and the subdural space. One or more of the first catheter 3710 and the second catheter 3720 may be withdrawn from the body.

[0334] In some embodiments, the catheter assembly may comprise one or more alignment features configured to align one of more of the catheters to each other. For example, FIG. 37E is a schematic side view of a catheter assembly 3700 comprising a first catheter 3710 and a second catheter 3720. The first catheter 3710 may be coupled to a first connector 3760 (e.g., Luer connector), and the second catheter 3720 may be coupled to a second connector 3762. In some embodiments, an outer surface of the first connector 3760 may comprise a first alignment feature 3750 (e.g., arrow, marker, indicator), and an outer surface of the secondconnector 3752 may comprise a second alignment feature 3752. The first and second alignment features 3750, 3752 may be aligned such that the first opening 3712 and second opening 3722 overlap to form an aperture through the catheter assembly 3700.

[0335] In some embodiments, a multi-component catheter assembly may be configured to biopsy tissue such as brain tissue. FIGS. 38A-38E are schematic side views of a catheter assembly 3800 including a first catheter 3810, a second catheter 3820, and a third catheter 3830 (e.g., biopsy device, perforating device). The first catheter 3810 may comprise a first lumen 3814 and a first fiducial 3812. The second catheter 3820 may be configured to translate through the first lumen 3814 and may comprise a first lumen 3822, a second lumen 3824, and a second fiducial 3826. The first lumen 3822 may have a first diameter and the second lumen 3824 may have a second diameter smaller than the first diameter. The first lumen 3822 may be configured to apply negative pressure and receive tissue. The second lumen 3824 may be configured to receive the third catheter 3830. The third catheter 3832 may comprise a distal portion 3832 coupled to a shaft 3834 (e.g., wire). The distal portion 3832 may be configured to receive, capture, and cut tissue. For example, the distal portion 3832 may have a hollow tapered shape (e.g., conical) and one or more proximal edges of the distal portion 3832 may comprise one or more cutting features. Additionally or alternatively, one or more distal edges of the second catheter 3820 may comprise one or more cutting features. Furthermore, the proximal edge of the distal portion 3832 may comprise a beveled edge relative to a longitudinal axis of the shaft 3834. For example, a proximal edge of the distal portion may have an angle with respect to a longitudinal axis of the shaft of between about 30 degrees and about 60 degrees, between about 30 degrees and about 45 degrees, between about 45 degrees and about 60 degrees, and between about 40 degrees and about 50 degrees, inclusive of all ranges and subranges therebetween. Alternatively, the proximal edge of the distal portion 3832 may be perpendicular to a longitudinal axis of shaft 3834. In some embodiments, the third catheter 3830 may be configured to translate within the second lumen 3824 of the second catheter 3820 such that the distal portion 3832 extends distal to a distal end of the second catheter 3826. In some embodiments, the third catheter 3830 may comprise one or more of a polymer, nylon, metal, stainless steel, nitinol, nitinol alloy, cobalt chromium, combinations thereof, and the like. In some embodiments, the shaft 3834 may comprise a lumen configured for fluid irrigation. For example, the lumen of the shaft 3834may be configured to provide a saline flush at a proximal end of the distal portion 3832 to assist one or more of tissue capture and removal.

[0336] In some embodiments, the catheter assembly 3800 may be advanced through a perforation point (e.g., wall of the MMA, dura) and into a subdural space. At least the third catheter 3830 may be inserted into tissue (e.g., brain) such that tissue is received within a lumen of the distal portion 3832. In some embodiments, negative pressure may be applied through the first lumen 3822 to suction brain tissue into the distal portion 3832 and facilitate tissue capture. One or more of the third catheter 3830 and second catheter 3820 may be translated toward each other to couple a distal end of the second catheter 3820 with the proximal end of the third catheter 3830 to cut tissue and thereby capture tissue within the catheter assembly 3800. For example, the third catheter 3830 may be withdrawn 3842 relative to the first catheter 3810 and the second catheter 3820 may be advanced 3840 relative to the first catheter 3810. FIG. 38E depicts the distal portion 3832 of the third catheter 3830 coupled to the second catheter 3820 such that tissue received within a lumen of the distal portion 3832 and the first lumen 3822 of the second catheter 3820 is captured and held securely within the catheter assembly 3800 for withdrawal from the body.Dilation Device

[0337] In some embodiments, a method of forming a passageway through a wall of an intracranial vessel and dura may comprise advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient. The catheter may define a lumen. A perforating element may be advanced through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel. A wall of the intracranial vessel and the dura may be perforated using the perforating element to form a passageway into the intracranial extravascular space. A dilation device may be advanced over the perforating element through the passageway. An expandable member of the dilation device may be transitioned into an expanded configuration to enlarge the passageway.

[0338] In some embodiments, the expandable member may include a balloon, a stent, or a basket. In some embodiments, the expandable member in the expanded configuration includes a tapered structure that increases in diameter proximally. In some embodiments, transitioning the expandable member into the expanded configuration may cause compressionagainst the dura and nearby bony structure to secure the dilation device in position for enlarging the passageway.

[0339] In some embodiments, after enlarging the passageway, the expandable member may transition back to an unexpanded configuration. The catheter may be advanced over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space. A surgical procedure may be performed via the catheter after the distal end of the catheter is disposed in the intracranial extravascular space. In some embodiments, performing the surgical procedure includes at least one of: draining fluid or matter from the intracranial extravascular space, performing a biopsy of brain matter, or delivering a therapy or a device.

[0340] For example, FIGS. 42 A and 42B are schematic cross-sectional side views 4200, 4202 of a catheter assembly in a head of a subject including a skull 4210, a vessel (e.g., MMA) 4220, a dura 4230, a subdural space 4240, and a brain 4250. A catheter assembly may include a sheath 4270, a perforating device 4280 disposed within a lumen of the sheath 4270, and a dilation device 4290 disposed within a lumen of the sheath 4270. As shown in 4200, the perforating device 4280 (e.g., any of the perforating devices described herein) may be advanced distal to the sheath 4270 and through one or more of the vessel wall 4220 and dura 4230 to create a transvascular passageway 4232 into one or more of the subdural space 4240 and subdural hematoma 4242. In some embodiments, the opening 4232 formed using the perforation device 428 may be relatively small in size (e.g., diameter, length), which may limit access to the subdural space 4240.

[0341] In some variations, a dilation device 4290 may be configured to dilate tissue to enlarge an opening 4232 and improve access to a subdural space. For example, as shown in 4202, a dilation device 4290 may be advanced distal to the sheath 4270 and over the perforating device 4280. In some embodiments, the dilation device 4290 may comprise an expandable member 4232 (e.g., balloon, stent, basket, mesh) configured to inflate or expand to a predetermined diameter. The expandable member 4232 of the dilation device 4290 may be configured to transition between a delivery configuration and an expanded configuration. The expandable member 4232 in an inflated configuration can form any suitable shape such as, for example, a round shape, a flat shape, or an oblong shape. In some embodiments, the expandable member 4232 when inflated can at least partially fill the vessel 4220 andcompress against (i.e., press against, abut, etc.) the dura 4230 and bone 4210, thereby securing (e.g., anchoring) the dilation device 4290 in a position for enlarging the opening 4232. In some embodiments, the dilation device 4290 may comprise a tapered shaft increasing in diameter from distal to proximal configured to mechanically dilate the opening 4232 to a larger diameter. An enlarged opening 4232 may facilitate delivery of larger devices into the subdural space 4240.Handle Assembly

[0342] FIG. 58 are schematic cross-sectional side views 5800, 5802 of a handle assembly 5830. For example, a mechanical handle may be coupled to a proximal end of a catheter assembly including a perforating device 5820 (e.g., shaft) and a catheter 5810. The perforating device 5820 may be slidably disposed within a lumen 5812 of the catheter 5810. The catheter 5810 may comprise an aperture 5814 in a sidewall of the catheter 5810. The perforating device 5820 may comprise a perforating element 5822 that may be advanced out of the aperture 5814 using the handle assembly 5830. A proximal portion 5844 of the perforating device 5820 may be coupled to the handle assembly 5830. In some embodiments, the handle assembly 5840 may comprise an actuator 5840, 5841 configured to translate the perforating device 5820 relative to the catheter 5810. For example, the actuator 5840 may be a slidable switch that may be translated (e.g., pressed) to move between a plurality of spaced apart grooves (e.g., notches) 5842 and provide corresponding movement to the perforating device 5820. Similarly, the actuator (e.g., knob) 5841 may be rotated between a plurality of grooves (e.g., gradations) 5842 to translate the perforating device 5820 in distal and proximal directions. The grooves 5842 may be configured to translate the perforating device 5820 at predetermined increments such that the perforating device 5820 may translate relative to the catheter 5810 at a predetermined length.Example Embodiments

[0343] FIG. 29 is a schematic diagram of a system 2900 including a catheter 2910, perforating device (e.g., shaft) 2920, connector 2940, and a signal generator 2950. The catheter 2910 and perforating device 2920 may include components that are structurally and / or functionally similar to the catheter 510 and perforating device 520, respectively, as described above with reference to FIG. 5. The system 2900 may be configured to form an opening between a blood vessel to an extravascular space of a subject and / or deliver aI l lhemostatic element or an RF device to close an opening formed by the perforating device 2920. In some embodiments, the catheter 2910 may be slidably disposed within a lumen of a sheath.

[0344] In some embodiments, the perforating device 2920 may be coupled to the signal generator 2950. The perforating device 2920 may include a distal tip portion 2922 having a perforating element 2924 configured to create (e.g., form) an opening in a wall of a blood vessel and a dura of the subject. In some embodiments, the distal tip portion 2922 may have a predetermined shape, such as, for example, a J-shaped curve, as further described below. Alternatively, in some embodiments, the distal tip portion 2922 can have a different predetermined or preset shape, e.g., a U-shape, a C-shape, or other atraumatic shape. In some embodiments, the perforating device 2920 (e.g., distal tip portion 2922) may further include an offset (not shown) configured to orient the perforating device 2920 in a predetermined orientation when the perforating device 2920 is advanced within the lumen of the catheter 2910 and a blood vessel. For example, the offset may be configured to rotate (e.g., selforient) the distal tip portion 2922 about a longitudinal axis of the perforating device 2920 such that the perforating element is directed toward the dura and brain while a proximal portion of the J-shaped distal tip portion faces the skull, thereby ensuring that the opening created by the perforating element 2930 is formed within an arc that faces the subdural space and not the skull. In this configuration, the system 2900 may function as a rotating lever, the fixed path of the vessel, bone, and dura may function as a fulcrum, the friction between the system 2900 and vessel functions as resistance, and the release of elastic potential energy corresponding to the predetermined curve of the system 2900 results in rotational motion and self-orientation for entry into a subdural space from vasculature.

[0345] As described in more detail herein, the perforating device 2920 may generally have a rounder cross-sectional shape (e.g., circular or oval) while the offset may have a relatively flatter ovoid cross-sectional shape configured to rotate or twist the distal tip portion 2922 to a desired orientation (e.g., facing away from the skull and towards the dura) when advanced through tortuous vasculature. The J-shaped curve of the distal tip portion 2922 may be advantageous in facilitating atraumatic advancement of the perforating device 2920 through a subdural space. The J-shaped curve may be constrained as the perforating device is advanced through vasculature, but may naturally form within a subdural space after the perforating device 2920 creates an opening through a blood vessel and dura. A distal end of the distal tipportion 2922 may include a perforating element 2930 such as an electrode configured to deliver RF energy. In some embodiments, the perforating element 2930 may be angled relative to the distal tip portion 2922.

[0346] In some embodiments, the connector 2940 may be configured to couple the catheter 2910 and perforating device 2920 to the signal generator 2950 and a vacuum source (not shown). In some embodiments, the signal generator 2950 may be coupled to the perforating device 2920. In particular, the signal generator 2950 may be configured to generate energy (e.g., RF energy) for delivery using the perforating element 2924 of the distal tip portion 2922.

[0347] In some embodiments, the catheter 2910 and / or perforating device 2920 may include a set of fiducials including a first fiducial 2930 and a second fiducial 2932 configured to by imaged and facilitate positioning of the system 2900 within the intravascular and extravascular spaces of the subject.

[0348] FIGS. 30A and 30C are schematic diagrams of a shaft assembly 3000, 3004 and FIGS. 30B, 30D, and 30E are detailed schematic diagrams of the shaft assembly 3002, 3006, 3008 depicted in FIGS. 30A and 30C, respectively. The shaft assembly 3000-3008 may include components that are structurally and / or functionally similar to the shafts described herein.

[0349] The shaft assembly 3000, 3002 shown in FIGS. 30A and 30B may include a handle 3010, a perforating element 3020, a first fiducial 3032, a second fiducial 3034, and a third fiducial 3036. In some embodiments, the first fiducial 3032 corresponds to a location of the perforating element 3020, the second fiducial 3034 facilitates confirmation of shaft selforientation, and the third fiducial 3036 corresponds to the location of the largest outer diameter of the shaft. In some embodiments, the perforating element 3020 and first fiducial 3032 may form an angle with respect to the second fiducial 3034 of between about 5° and about 15°, inclusive of all ranges and subranges therebetween. In some embodiments, the bent portion of the shaft assembly formed by the perforating element 3020 and first fiducial 3032, as shown in FIG. 30B, may have a length extending along a longitudinal axis of the shaft assembly 3000 between about 2.3 cm and about 2.7 cm, inclusive of all ranges and subranges therebetween.

[0350] The shaft assembly 3004, 3006 shown in FIGS. 30C and 30D further depict a distal tip portion 3040 of the shaft. The distal tip portion 3040 may have a perforating element 3020 configured to create (e.g., form) an opening in a wall of a blood vessel and a dura of the subject. In some embodiments, the distal tip portion 3040 may have a predetermined shape such as a J-shaped curve. A distal end of the distal tip portion 3040 may include the perforating element 3020 such as an electrode configured to deliver RF energy. In some embodiments, as shown in FIGS. 30C and 30D, the perforating element 3020 may be angled relative to the distal tip portion 3040. While disposed within a vessel (e.g., MMA), the shape of the distal tip portion 3040 may be constrained by the vessel such that the J-shape is not formed within the vessel. Once the distal tip portion 3040 is advanced out of an opening in the vessel and dura, the unconstrained shape of the distal tip portion 3040 may be formed. In some embodiments, the set of fiducials 3032, 3034, 3036 may be configured to be imaged (e.g., visualized) to facilitate positioning of the shaft assembly 3000-3008 within the intravascular and extravascular spaces of the subject.

[0351] In some embodiments, the shaft may have a length of at least about 130 cm (e.g., between about 160 cm and about 180 cm) from a femoral or a radial access point. The shaft may be shorter when using a cervical access point. In some embodiments, the perforating element 3020 may be angled towards the shaft to concentrate energy delivery by the perforating element 3020 to tissue at a contact point in order to vaporize tissue and minimize heat generation and tissue shrinkage. Additionally or alternatively, higher energy levels that vaporize (e.g., ablate) more tissue may be used to create a transvascular passageway (e.g., when the perforating element 3020 does not include a contact point that focuses energy delivery). In some embodiments, as shown in FIGS. 30C and 30D, the perforating element 3020 may form an angle with respect to a distal end of the distal tip portion 3040 of between about 15° and about 35°, inclusive of all ranges and subranges therebetween.

[0352] In some embodiments, a height of the curved portion of the distal tip portion may be between about 0.5 cm and about 2.0 cm, inclusive of all ranges and subranges therebetween. In some embodiments where the shaft forms a J-shape such as in FIGS. 30C and 30D.

[0353] The perforating element 3020 may have an angle and length configured to provide depth-controlled perforation of an MMA and dura but not the brain. In some embodiments, a distance between a distal end of the perforating element 3030 and a distal end of the shaft(e.g., defined by the curved portion of distal tip portion 3040) may be between about 1 cm and about 1.4 cm, inclusive of all ranges and subranges therebetween.

[0354] In some embodiments, an outer diameter of the shaft may vary along its length in a predetermined manner. For example, the shaft may have a first outer diameter 3033 and a second outer diameter 3035 larger than the first outer diameter 3035. In some embodiments, a first outer diameter 3033 of the shaft may generally be between about 0.020 inches and about 0.027 inches, inclusive of all ranges and subranges therebetween. A second outer diameter 3035 of the shaft may generally be between about 0.0255 inches and about 0.0270 inches, inclusive of all ranges and subranges therebetween. The outer diameter of the shaft may taper from the first outer diameter 3033 to the second outer diameter 3035 and back to the first outer diameter 3033, as shown in FIG. 30E, for a length of between about 4 mm and about 6 mm, inclusive of all ranges and subranges therebetween. In some embodiments, a first fiducial 3032 (e.g., distal most fiducial) may have the second outer diameter 3035 while the rest of the shaft has the first outer diameter 3033.

[0355] In some embodiments, the second outer diameter may substantially match (e.g., within 0.002 inches) an inner diameter of a corresponding catheter so as to reduce and / or restrict longitudinal advancement of the shaft relative to the catheter. This may aid parallel advancement of the shaft and catheter through a subdural space where the shaft and catheter are fixed relative to each other.

[0356] FIG. 31 is a schematic diagram of a shaft assembly 3100 corresponding to a linear tip RF device. The shaft assembly 3100 may include components that are structurally and / or functionally similar to the shafts described herein. The shaft assembly 3100 may include a handle 3110 and a shaft 3120. The shaft 3120 may include a perforating element 3130 and a fiducial 3140. The perforating e...

Claims

1. CLAIMS1. A method of accessing an intracranial extravascular space of a patient, the method comprising: advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient, the catheter defining a lumen; advancing a perforating element through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel; obliquely perforating a wall of the intracranial vessel using the perforating element while the perforating element extends substantially parallel to the intracranial vessel to form an opening into the intracranial extravascular space; advancing the distal end of the perforating element within the intracranial extravascular space; advancing the catheter over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space; performing an endovascular procedure via the catheter after the distal end of the catheter is disposed in the intracranial extravascular space; and closing, after performing the endovascular procedure, the opening.

2. The method of claim 1, further comprising: forming, using the perforating element, an epidural channel, wherein closing the opening includes placing an occlusion device in the intracranial extravascular space and occluding the epidural channel and the intracranial vessel using the occlusion device.

3. The method of claim 1, wherein closing the opening includes: implanting an occlusion device, delivering an embolization agent, or applying energy to a portion of the intracranial vessel.

4. The method of any one of claims 1-3, wherein performing the endovascular procedure includes at least one of: draining fluid or matter from the intracranial extravascular space, performing a biopsy of brain matter, or delivering a therapy or a device.

5. The method of any one of claims 1-4, wherein advancing the catheter over the perforating element includes advancing the catheter over the perforating element by more than 0.5 cm within the intracranial extravascular space.

6. The method of any one of claims 1-5, wherein obliquely perforating the wall of the intracranial vessel includes applying energy via the perforating element to the wall of the intracranial vessel.

7. The method of any one of claims 1-6, further comprising obliquely perforating the dura to form a passageway into the subdural space, wherein the endovascular procedure is performed in the subdural space.

8. The method of any one of claims 1-7, wherein the intracranial vessel is the middle meningeal artery.

9. A method of forming a passageway through a wall of an intracranial vessel and dura, the method comprising: advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within the intracranial vessel, the catheter defining a lumen; advancing a perforating element through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel; directionally guiding the perforating element toward a wall of the intracranial vessel and the dura using anatomical features proximate to the intracranial vessel; and obliquely perforating the wall of the intracranial vessel and the dura using the perforating element while the perforating element is directionally guided toward the wall of the intracranial vessel and the dura to form a passageway into the intracranial extravascular space.

10. The method of claim 9, wherein obliquely perforating the wall of the intracranial vessel and the dura includes applying energy using the perforating element to the wall of the intracranial vessel and the dura to perforate therethrough.

11. The method of claim 10, further comprising rotating or applying torque to the perforating element to enable circumferential application of energy to vaporize the wall of the intracranial vessel and the dura to form the passageway into the transcranial extravascular space.

12. The method of claim 9, wherein the passageway is formed at the lower skull.

13. The method of claim 9, wherein the anatomical features include at least one of: a bony ridge of an inner surface of the skull, a bony overhang of the skull, or a bony channel of the skull.

14. The method of claim 9, wherein the perforating element has a linear tip, and directionally guiding the perforating element toward the wall of the intracranial vessel and the dura includes using a bony feature of the skull adjacent to the intracranial vessel to direct the linear tip of the perforating element toward the wall of the intracranial vessel and the dura.

15. The method of claim 9, wherein the perforating element has a curved tip configured to curve toward the wall of the intracranial vessel and the dura.

16. The method of any one of claims 9-15, wherein the intracranial vessel is the middle meningeal artery.

17. The method of any one of claims 9-15, further comprising: advancing the catheter over the perforating element and into the intracranial extravascular space; and draining, via the catheter, fluid or matter from the intracranial extravascular space.

18. The method of any one of claims 9-15, further comprising: advancing the catheter over the perforating element and into the intracranial extravascular space; anddelivering, via the catheter, a therapy or a device to the intracranial extravascular space.

19. A method of forming a passageway through a wall of an intracranial vessel and dura, the method comprising: advancing a catheter within a vasculature of a patient until a distal end of the catheter is disposed within an intracranial vessel of the patient, the catheter defining a lumen; advancing a perforating element through at least a portion of the lumen of the catheter such that a distal end of the perforating element is disposed in the intracranial vessel; perforating a wall of the intracranial vessel and the dura using the perforating element to form a passageway into the intracranial extravascular space; advancing a dilation device over the perforating element through the passageway; and transitioning an expandable member of the dilation device into an expanded configuration to enlarge the passageway.

20. The method of claim 19, wherein the expandable member includes a balloon, a stent, or a basket.

21. The method of claim 19, wherein the expandable member in the expanded configuration includes a tapered structure that increases in diameter proximally.

22. The method of claim 19, wherein transitioning the expandable member into the expanded configuration causes compression against the dura and nearby bony structure to secure the dilation device in position for enlarging the passageway.

23. The method of claim 19, further comprising: transitioning, after enlarging the passageway, the expandable member back to an unexpanded configuration; advancing the catheter over the perforating element until a distal portion of the catheter is disposed in the intracranial extravascular space; and performing an endovascular procedure via the catheter after the distal end of the catheter is disposed in the intracranial extravascular space.

24. The method of claim 23, wherein performing the endovascular procedure includes at least one of: draining fluid or matter from the intracranial extravascular space, performing a biopsy of brain matter, or delivering a therapy or a device.

25. An apparatus, comprising: an elongate body defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel; and a plurality of apertures disposed on the distal end of the elongate body, the plurality of apertures configured to drain fluid or matter from an intracranial extravascular space, the elongate body configured to be steerable to a location in the intracranial vessel, the elongate body further configured to receive a perforating device through the lumen such that the perforating device can be advanced into the intracranial vessel to perforate a wall of the intracranial vessel and to form a passageway into the intracranial extravascular space, the elongate body further configured to be advanced over the perforating device into the intracranial extravascular space such that the plurality of apertures can drain fluid or matter from the intracranial extravascular space.

26. The apparatus of claim 25, wherein the plurality of apertures are disposed on a distal length of the elongate body having a length of between about 1 cm and about 10 cm.

27. The apparatus of claim 25, wherein the plurality of apertures include at least one of holes, slits, or slots.

28. The apparatus of claim 25, wherein the plurality of apertures have one or more of a circle, an oval, an ellipse, a square, a star, a diamond, a rectangle, or an elongate shape.

29. The apparatus of claim 25, wherein the distal end of the elongate body is formed from a braid that defines the plurality of apertures.

30. The apparatus of any one of claims 25-29, wherein the distal end of the elongate body is configured to transition to a treatment configuration having a non-linear, shaped section.

31. The apparatus of claim 30, wherein the non-linear shaped section includes one or more markers configured to indicate a shape or a location of the non-linear shaped section.

32. The apparatus of any one of claims 25-29, further comprising one or more expandable elements or protrusions configured to reduce an occlusion of one or more of the plurality of apertures.

33. The apparatus of any one of claims 25-29, further comprising a pull wire or a magnet configured to enable the elongate body to be steered within a vasculature to the location in the intracranial vessel.

34. An apparatus, comprising: an elongate body defining a lumen, the elongate body including a distal end configured to be disposed in an intracranial vessel, the lumen including a distal curve; and an opening disposed on the distal end of the elongate body, the opening being in communication with the lumen, the elongate body configured to be steerable to a location in the intracranial vessel, the elongate body further configured to receive a perforating device through the lumen such that the perforating device can be guided via the distal curve and out through the opening toward a wall of the intracranial vessel to perforate the wall and form a passageway into the intracranial extravascular space.

35. The apparatus of claim 34, further comprising a pull wire or a magnet configured to enable the elongate body to be steered within a vasculature to the location in the intracranial vessel.

36. The apparatus of claim 34, wherein the distal curve is configured to direct the perforating device out through the opening at an angle of between about 5 degrees and about 90 degrees from a plane perpendicular to a longitudinal axis of the elongate body.

37. The apparatus of claim 34, further comprising one or more markers configured to indicate a position of the elongate body within the intracranial vessel.

38. An apparatus, comprising: an elongate body defining a lumen, the elongate body including a proximal end having a first coupling portion and a distal end configured to be disposed in an intracranial vessel; a perforating device including a second coupling portion, the perforating device configured to be advanced through the lumen of the elongate body until the second coupling portion of the perforating device engages with the first coupling portion of the elongate body, the perforating device, when advanced such that the first and second coupling portions are engaged, further configured to perforate through a wall of the intracranial vessel to form a passageway into the intracranial extravascular space.

39. The apparatus of claim 38, further comprising a wire coupled to the proximal end of the elongate body, the wire configured to distally advance the elongate body.

40. The apparatus of claim 38, wherein the perforating device includes a paddle structure configured to apply energy to the wall of the intracranial vessel to form the passageway into the intracranial extravascular space, the paddle structure configured to act as a heat sink during application of the energy.

41. The apparatus of claim 40, wherein the perforating device includes an insulating material disposed along a length of the perforating device proximal of the paddle structure, the paddle structure having an outer diameter that provides a smooth transition from the insulating material to the paddle structure.

42. The apparatus of claim 38, wherein the perforating device includes a needle configured to mechanically perforate the wall of the intracranial vessel to form the passageway into the intracranial extravascular space.

43. The apparatus of claim 42, wherein the needle includes one or more of an angled opening, a circumferential spiral cut opening, a spiral opening, or external threading.

44. The apparatus of any one of claims 38-43, wherein at least one of the elongate body or the perforating device includes one or more fluoroscopic markers configured to be imaged by a visualization device to indicate a location or a configuration of the at least one of the elongate body or the perforating device.

45. The apparatus of any one of claims 38-43, further comprising an expandable element configured to expand to anchor the elongate body within the intracranial vessel.

46. The apparatus of any one of claims 38-43, further comprising an energy delivery device configured to be advanced through the lumen and into the intracranial vessel, the energy delivery device configured to deliver bipolar energy to the intracranial vessel to coagulate the intracranial vessel.

47. The apparatus of any one of claims 38-43, wherein the perforating device is further configured to apply energy to the intracranial vessel to coagulate the intracranial vessel.

48. The apparatus of any one of claims 38-43, further comprising a hemostatic device configured to occlude the intracranial vessel.

49. The apparatus of claim 48, wherein the hemostatic device includes a carrier structure and a hydrogel disposed around the carrier structure, the hydrogel configured to expand to occlude the intracranial vessel.

50. The apparatus of claim 48, wherein the hemostatic device is configured to transition to a preformed shape that facilitates anchoring to the wall of the intracranial vessel or nearby anatomy.

51. The apparatus of any one of claims 38-43, further comprising a pressure sensor configured to capture pressure measurements at a distal end of the perforating device to monitor a location or state of the perforating device.

52. An apparatus, comprising:an elongate body defining a lumen, the elongate body including a distal end configured to be advanced through an intracranial vessel and into an intracranial extravascular space over a shaft, the elongate body further including a proximal end configured to be coupled to a source of therapy such that the therapy can be delivered to the intracranial extravascular space via the catheter; and an anchor coupled to the elongate body and configured to expand to releasably anchor the elongate body to tissue.

53. The apparatus of claim 52, wherein the intracranial vessel is the middle meningeal artery.

54. The apparatus of claim 52, wherein the shaft is a perforating device that is configured to perforate a wall of the intracranial vessel to form a passageway into the intracranial extravascular space, the elongate body being configured to be advanced over the shaft and through the passageway into the intracranial extravascular space.

55. The apparatus of claim 52, further comprising a sensor configured to monitor a state of the elongate body or a condition within the intracranial extravascular space.

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