Systems, apparatus, and methods for access to subdural space

Abstract

Systems, devices, and methods for accessing a subdural space are disclosed herein. In some embodiments, a device may include a shaft configured to be slidably disposed within a lumen of a catheter. The shaft may be configured to advance distally from a distal end of the catheter and into a blood vessel of a subject. The shaft may include a perforated tip including an energy element configured to generate radiofrequency energy to form an opening through a wall and dura mater of the blood vessel of the subject and into an extravascular lumen of the subject. A bending section may be configured to be radially constrained within the lumen of the catheter and bend toward the wall of the blood vessel and the dura mater upon exiting the lumen of the catheter such that the energy element is positioned to form the opening.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a continuation-in-part of U.S. patent application No. 18 / 469,437, filed on September 18, 2023, which is a continuation-in-part of U.S. patent application No. 17 / 976,667, filed on April 27, 2021, which is a continuation-in-part of PCT application No. PCT / US2021 / 029276, filed on April 27, 2021, which claims priority to U.S. provisional application No. 63 / 016,613, filed on April 28, 2020, the contents of each of which are incorporated herein by reference in their entirety.

[0003] This application also claims priority to and is a continuation-in-part of U.S. Provisional Application No. 18 / 469,376, filed September 18, 2023, and claims priority to U.S. Provisional Application No. 63 / 422,799, filed November 4, 2022, the contents of each of which are incorporated herein by reference in their entirety. U.S. Patent Application No. 18 / 469,376, filed September 18, 2023, also claims priority to U.S. Provisional Application No. 63 / 422,799, filed November 4, 2022. Technical Field

[0004] The devices, systems, and methods herein relate to minimally invasive procedures for accessing an intracranial extravascular space within a subject, including but not limited to treating a subdural hematoma. Background Art

[0005] Subdural hematoma (SDH) is an accumulation of blood outside the brain, usually caused by head trauma and often associated with blood thinners. If surgical drainage is not performed, SDH may cause increased pressure within the skull, destroy fragile brain tissue, and be life-threatening. Initially, acute SDH (aSDH) is usually formed by a hard clot, but may gradually liquefy into viscous subacute SDH (saSDH) over the next few days, which tends to persist and expand into chronic SDH (cSDH). Chronic subdural hematoma (cSDH) is an accumulation of blood on the surface of the brain, which usually begins to form and expands several weeks after head trauma, with the possibility of causing brain compression, neurological deficits and death. It is estimated that by 2030, cSDH will be the most common neurosurgical diagnosis in the United States, and has an in-hospital mortality rate of 16.7%, a 1-year mortality rate of 32%, only 21.1% of hospitalized patients return home, and is associated with a significant reduction in patient life expectancy. cSDH is becoming a public health concern in the aging population because it is associated with brain atrophy in elderly patients and with anticoagulation using blood thinners. Furthermore, acute-on-chronic SDH (acSDH) occurs in more than 10% of patients with cSDH and may be formed by an encapsulated liquefied hematoma mixed with a solid subdural clot.

[0006] The current standard of care for symptomatic SDH is surgical evacuation. For example, two burr holes are formed to drain relatively thin cSDH, and a craniotomy (e.g., a large bone 'window') is used to drain the viscous fluid and / or clots of aSDH and acSDH. Surgical evacuation may be effective initially, but the failure rate is as high as about 37%. Even when initial conventional treatment fails and the patient undergoes a second surgical treatment, further recurrence is common; the recurrence rate of cSDH can be as high as about 46%. In addition, open surgical intervention may bring additional risks to the patient, including temporary discontinuation of anticoagulant and antiplatelet drugs (e.g., thereby increasing the risk of ischemic complications) and the use of general anesthesia, which may result in morbidity and mortality rates of up to about 25% and about 11%, respectively.

[0007] Surgical evacuation is often combined with the placement of drains in the subdural space, which typically remain in place for about three days. Although drains reduce recurrence and six-month mortality by about 50%, they can also lead to other complications, such as brain damage, bleeding from the new membrane, and infection.

[0008] Intravascular middle meningeal artery (MMA) embolization is an intravascular procedure used to reduce the recurrence of SDH after surgery. It involves injecting an embolic agent into the MMA, whereby the hematoma is slowly resorbed, reducing the pressure effect on the brain over a period of weeks to months. MMA embolization can be used to treat cSDH and reduce recurrence in high-risk patients with aSDH, saSDH, and acSDH (i.e., coagulopathy or the need for blood thinners).

[0009] Surgical evacuation for rapid brain decompression has been used in conjunction with endovascular MMA as a preoperative or postoperative adjunct to the treatment of SDH. However, this combination carries its aforementioned risks and requires two separate procedures, which can increase hospitalization, recovery time, and healthcare costs. Therefore, it may be desirable to provide an endovascular procedure to access the subdural space to facilitate evacuation of SDH and arterial embolization. Summary of the Invention

[0010] Described herein are systems, devices, and methods for minimally invasive surgical procedures. These systems, devices, and methods can, for example, access the subdural space (e.g., intradural cavity) and treat an intracranial hematoma in a 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 intravascular intervention (e.g., approach) are described herein.

[0011] In some embodiments, a device for draining a subdural hematoma disposed in an extracranial cavity of a patient's intracranial blood vessel may include a suction catheter that may be disposed within the patient's intracranial blood vessel, the suction catheter defining a lumen. A shaft may be configured to be advanced through the lumen of the catheter until the distal end portion of the shaft is disposed within the intracranial blood vessel. The shaft may include a perforating element configured to cut through the wall and dura mater of the patient's intracranial blood vessel to create a slit that serves as a passage from the lumen of the intracranial blood vessel to the extracranial cavity of the intracranial blood vessel. A distal segment may be coupled to the distal end portion, the distal segment having a cross-section having a first lateral dimension greater than a second lateral dimension so that the shaft bends in a first plane and is constrained to bend in a second plane perpendicular to the first plane. The suction catheter may be configured to be advanced through the slit and reach the subdural hematoma to allow fluid or material from the subdural hematoma to be drained from the extracranial cavity of the intracranial blood vessel via the lumen of the catheter.

[0012] In some embodiments, the perforating element can be configured to deliver between about 1200 A / m 2 and about 12000A / m 2In some embodiments, the perforated element can be configured to deliver a power between about 10 W and about 100 W. In some embodiments, the perforated element can include a tip bending stiffness of up to about 15 gf. In some embodiments, the shaft has a column strength of up to about 100 gf.

[0013] In some embodiments, the shaft may further include a wider section having a lateral dimension that is equal to or substantially equal to the inner diameter of the lumen of the suction catheter to prevent ovalization of the suction catheter when the suction catheter is advanced through the longitudinal slit. In some embodiments, the suction catheter may include a proximal end portion that is configured to be coupled to a suction source so that the suction source can apply suction to the lumen to drain the fluid or substance from the subdural hematoma. In some embodiments, the perforating element may have an atraumatic shape. In some embodiments, the shaft may further include a proximal section having an outer diameter that tapers from a first outer diameter that is substantially equal to the inner diameter of the suction catheter to a second outer diameter so that the proximal section is configured to limit the length by which the shaft can be advanced distally beyond the distal end portion of the suction catheter.

[0014] In some embodiments, the device may further include a sheath defining a sheath lumen configured to receive the aspiration catheter. The aspiration catheter may include a distal segment comprising a proximal portion having an outer diameter tapered from a first outer diameter substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion is configured to limit the length to which the distal segment can be distally advanced beyond the distal end of the sheath.

[0015] In some embodiments, a device for draining a subdural hematoma disposed in an extracranial cavity of an intracranial blood vessel of a patient may include a suction catheter that may be disposed within the intracranial blood vessel of the patient, the suction catheter defining a lumen. An axis may be configured to advance through the lumen of the suction catheter until the distal end portion of the axis is disposed within the intracranial blood vessel, the distal end portion being coaxial with the axis. The axis may include a perforating element disposed at the distal end of the distal end portion, the perforating element being configured to obliquely cut through the wall and dura mater of the intracranial blood vessel of the patient to create a passage from the intracranial blood vessel to the extracranial cavity of the intracranial blood vessel. The suction catheter may be configured to advance through the passage and reach the subdural hematoma to allow fluid or material from the subdural hematoma to be drained out of the extracranial cavity of the intracranial blood vessel via the lumen of the catheter.

[0016] In some embodiments, the perforating element can be configured to deliver between about 1200 A / m 2 and about 12000A / m 2In some embodiments, the perforated element can be configured to deliver a power between about 10 W and about 100 W. In some embodiments, the perforated element can include a tip bending stiffness of up to about 15 gf. In some embodiments, the shaft can have a column strength of up to about 100 gf.

[0017] In some embodiments, the shaft may further include a wider section having a lateral dimension equal to or substantially equal to the inner diameter of the lumen of the aspiration catheter to prevent ovalization of the aspiration catheter as it is advanced through the longitudinal slit.

[0018] In some embodiments, the suction catheter may include a proximal end configured to be coupled to a suction source such that the suction source can apply suction to the lumen to drain the fluid or material from the subdural hematoma. In some embodiments, the perforating element may have an atraumatic shape. In some embodiments, the shaft may further include a proximal section having an outer diameter tapered from a first outer diameter substantially equal to the inner diameter of the suction catheter to a second outer diameter such that the proximal section is configured to limit the length to which the shaft can be advanced distally beyond the distal end of the suction catheter.

[0019] In some embodiments, the device may further include a sheath defining a sheath lumen configured to receive the aspiration catheter. The aspiration catheter may include a distal segment comprising a proximal portion having an outer diameter tapered from a first outer diameter substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion is configured to limit the length to which the distal segment can be distally advanced beyond the distal end of the sheath.

[0020] In some embodiments, a method may include: positioning the distal end of a catheter disposed within an intracranial blood vessel of a subject near a target location; advancing a shaft through the lumen of the catheter; extending the distal end portion of the shaft outside of and coaxial with the distal end of the catheter to position a radio frequency (RF) element of the distal end portion against a wall of the blood vessel and at an oblique angle relative to an overlying surface of the dura mater; activating the radio frequency (RF) element to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the blood vessel of the subject and into an extravascular intracranial cavity; advancing the distal end of the shaft into the extravascular intracranial cavity substantially parallel to the surface of the dura mater; and advancing the catheter over the shaft and into the extravascular intracranial cavity.

[0021] In some embodiments, the method may further include: advancing the distal end of the shaft into the subdural hematoma; and advancing the catheter over at least a portion of the shaft and into the subdural hematoma; and after the catheter is positioned within the subdural hematoma, applying suction to the lumen of the catheter to remove fluid from the subdural hematoma. In some embodiments, the method may further include: withdrawing the catheter toward the opening created in the wall of the artery; and delivering a hemostatic element or RF device through the lumen of the catheter to close the opening.

[0022] In some embodiments, a device may include a shaft configured to be slidably disposed within the lumen of a catheter. The shaft may be configured to be advanced distally from the distal end of the catheter and into a subject's blood vessel. The shaft may include a perforated tip comprising an energy element. The energy element may be configured to generate radiofrequency (RF) energy to form an opening through the wall and dura mater of the subject's blood vessel and into the subject's extravascular lumen. A curved segment may be configured to be radially constrained within the lumen of the catheter. The curved segment may be configured to bend toward the wall and dura mater of the blood vessel upon exiting the lumen of the catheter, such that the energy element is positioned to form the opening. A first discontinuity may be disposed between the perforated tip and the curved segment. A second discontinuity may be disposed proximal to the curved segment. The second discontinuity is configured to orient the curve to follow the curve of the blood vessel as the shaft is advanced within the lumen of the catheter.

[0023] In some embodiments, the first discontinuity comprises a bend in the shaft. In some embodiments, the curved segment has a first radius of curvature, and the first discontinuity comprises a segment of the shaft having a second radius of curvature that is smaller than the first radius of curvature. In some embodiments, the curved segment can be configured to transition into a curved configuration as the curved segment travels through the opening and into the extravascular lumen.

[0024] In some embodiments, the curved section may have a cross-section having a first lateral dimension that is greater than a second lateral dimension. In some embodiments, the second discontinuity may comprise a bend in the shaft. In some embodiments, the second discontinuity may comprise a partial spiral or twist in the shaft. In some embodiments, the curved section may have a first curved section comprising a convex curvature, and the shaft further comprises a second curved section proximal to the first curved section, the second curved section comprising a concave curvature. In some embodiments, the shaft may comprise a wider section having a lateral dimension that is equal to or substantially equal to the inner diameter of the lumen of the catheter to prevent ovalization of the catheter as the catheter is advanced through the opening. In some embodiments, the length of the opening is equal to or substantially equal to the length of the energy element.

[0025] In some embodiments, a system may include a catheter having a proximal end and a distal end, and defining a lumen between the proximal end and the distal end. The distal end of the catheter may be configured to be positioned within a blood vessel of a subject. A shaft may be slidably disposed within the lumen, the shaft including a perforated tip having an energy element configured to generate RF energy to penetrate the wall and dura mater of the blood vessel of the subject. The shaft may also include a bending section configured to transition from a radially constrained configuration to a curved configuration. The shaft may be configured to be advanced along the catheter such that the bending section is oriented to bend along the curve of the blood vessel and away from the distal end of the catheter. The bending section may be configured to bend toward the wall of the blood vessel such that the perforated tip is positioned against the wall of the blood vessel and, when the energy element is activated, can penetrate the wall of the blood vessel and the dura mater and enter the extravascular lumen.

[0026] In some embodiments, the distal end of the catheter may include a radiopaque element. In some embodiments, the shaft may include a first radiopaque element disposed at the perforated end and a second radiopaque element disposed proximal to the curved section. In some embodiments, the catheter may be configured to be advanced over the shaft into the extravascular cavity. The shaft may also include a wider section disposed proximal to the curved section that prevents ovalization of the catheter as the catheter is advanced into the extravascular cavity. In some embodiments, the distal end of the catheter may include a first radiopaque element, and the shaft may include a second radiopaque element disposed proximal to the wider section so that the wider section can be aligned with the distal end of the catheter before advancing the catheter into the extravascular cavity.

[0027] In some embodiments, the shaft is a first RF device, and the system further comprises a second RF device comprising a linear tip configured to penetrate the membrane of a subdural hematoma. In some embodiments, the second RF device is configured to deliver RF energy to close the vessel lumen of the blood vessel.

[0028] In some embodiments, a method includes: positioning a distal end of a catheter disposed within an intracranial blood vessel of a subject near a target location; advancing a shaft through a lumen of the catheter so that a curved segment of the shaft bends in a direction along the curve of the blood vessel, the curved segment being constrained within the lumen of the catheter; extending the curved segment of the shaft beyond the distal end of the catheter so that the curved segment bends toward a wall of the blood vessel, and positioning an RF element disposed at the distal end of the shaft against the wall of the blood vessel; activating the RF element to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the blood vessel of the subject and into an extravascular intracranial cavity; advancing the distal end of the shaft into the extravascular intracranial cavity until the curved segment transitions to an unconstrained configuration within the extravascular intracranial cavity; and advancing the catheter over the shaft and into the extravascular intracranial cavity.

[0029] In some embodiments, the method further comprises: advancing the distal end of the shaft into the subdural hematoma; advancing the catheter over at least a portion of the shaft and into the subdural hematoma; and after the catheter is positioned within the subdural hematoma, applying suction to the lumen of the catheter to remove fluid from the subdural hematoma. In some embodiments, the method further comprises: withdrawing the catheter toward the opening created in the wall of the artery; and delivering a hemostatic element or RF device through the lumen of the catheter to close the opening. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic coronal cross-sectional view of a subdural hematoma in a subject according to an embodiment.

[0031] Figure 2 is a schematic perspective view of a subject undergoing surgical evacuation, according to an embodiment.

[0032] Figure 3A is a schematic representation of a side view of a subject's head, according to an embodiment. Figures 3B to 3D is a coronal cross-sectional view of a subject's head, according to an embodiment.

[0033] Figure 4A and Figure 4B is an X-ray image of arterial blood flow in the head of a subject according to an embodiment. Figure 4C is an X-ray image of a subject's head according to an embodiment.

[0034] Figure 5 is a schematic block diagram of a system according to an embodiment.

[0035] Figure 6 is a schematic diagram of a system according to an embodiment.

[0036] Figure 7A and Figure 7C is a schematic diagram of a shaft according to an embodiment. Figure 7B 、 Figure 7D and Figure 7E are respectively Figure 7A and Figure 7C Detailed schematic diagram of the axis depicted in .

[0037] Figures 8A to 8C is an image of the axis according to the embodiment.

[0038] Figure 9 is a schematic diagram of a shaft according to an embodiment.

[0039] Figure 10 is a flow chart of a method of accessing an extravascular lumen, according to an embodiment.

[0040] Figures 11A to 11L is an image of a method of accessing an extravascular intracranial space according to an embodiment.

[0041] Figure 12A and Figure 12B is a schematic diagram of tissue impedance according to an embodiment.

[0042] Figure 13A 、 Figure 13B 、 Figure 13D 、 Figure 13E 、 Figure 13G and Figure 13I is a coronal cross-sectional view of a subject's head, according to an embodiment. Figure 13C is a schematic axial cross-sectional view of a subject's head, according to an embodiment. Figure 13F 、 Figure 13H and Figure 13J is a side view of a subject's head, according to an embodiment.

[0043] Figure 14A 、 Figure 14C and Figure 14E is a coronal cross-sectional view of a subject's head, according to an embodiment. Figure 14B 、 Figure 14D and Figure 14F is a side view of a subject's head, according to an embodiment.

[0044] Figure 15A is an image of a dissected cadaver head, according to an embodiment. Figure 15B is a side view of a 3D computed tomography scan of a subject's head, according to an embodiment.

[0045] Figure 16 is a perspective cross-sectional view of a subject's head according to an embodiment.

[0046] Figure 17Aare schematic sagittal and axial cross-sectional views of a subject's head, according to an embodiment. Figures 17B to 17E is a schematic sagittal cross-sectional view of a subject's head, according to an embodiment.

[0047] Figure 18 is a plot of fluid shear rate and viscosity for chronic and subacute subdural hematomas, according to an embodiment.

[0048] Figure 19A It is a top view of the hematoma heat map. Figure 19B is an overlay of a hematoma heatmap and a set of arterial perforation trajectories according to an embodiment. Figure 19C is an overlay of a hematoma heatmap and a set of arterial perforation locations according to an embodiment. Figure 19D is a plot of probabilities that the set of arterial perforation trajectories intersect the set of arterial perforation locations, according to an embodiment.

[0049] Figure 20A is a three-dimensional image of a set of veins and dural sinuses in a subject's head, according to an embodiment. Figure 20B is a coronal cross-sectional view of a subject's head, according to an embodiment.

[0050] Figure 21A is a schematic top view of a subject's head according to an embodiment. Figure 21B is a schematic coronal cross-sectional view of a subject's head according to an embodiment.

[0051] Figure 22 are schematic top and coronal cross-sectional views of a subject's head according to an embodiment.

[0052] Figure 23 are schematic side and cross-sectional views of a shaft according to an embodiment.

[0053] Figure 24 are schematic top and coronal cross-sectional views of a subject's head, according to an embodiment.

[0054] Figure 25 is a schematic coronal cross-sectional view of a subject's head, according to an embodiment.

[0055] Figure 26 is a plot of dielectric constant and frequency for a set of tissue types, according to an embodiment.

[0056] Figure 27 is a plot of dielectric constants for a set of tissue types for a set of RF frequencies, according to an embodiment.

[0057] Figure 28 is a coronal cross-sectional view of a catheter assembly positioned in a subject's head, according to an embodiment. DETAILED DESCRIPTION

[0058] Described herein are systems, devices, and methods for minimally invasive surgical procedures that enable transvascular neurosurgery to be performed without opening the skull. For example, systems, devices, and methods described herein can improve access to the extravascular space (e.g., subdural space, epidural space, subarachnoid space, extravascular spinal space) and extravascular organs (e.g., brain, spinal cord) of a subject by the following: perform under minimal sedation; reduce one or more of procedure complexity, sterile field management, and time; enable the continued use of anticoagulant and antiplatelet drugs; provide faster postoperative recovery and shorten hospital stay; and reduce complications compared to conventional open surgical procedures. For example, access to the extravascular space can include navigation within a body cavity without blood extravasation when a vessel is unobstructed or (e.g., due to perforation) tissue destruction. In some embodiments, access to the subdural space can be used to facilitate drainage of subdural fluid.

[0059] While conventional solutions require separate procedures to drain a subdural hematoma (SDH) and embolize an artery, the systems, devices, and methods disclosed herein can be performed within a single intravascular approach. For example, the systems, devices, and methods described herein can facilitate immediate brain decompression through transvascular drainage of an SDH and prevention of hematoma recurrence by embolizing an MMA within the same procedure, thereby eliminating the need for a second and separate invasive open surgical procedure.

[0060] In some embodiments, the system and apparatus may include a first catheter configured to be self-oriented within the blood vessel so as to cut through the vessel wall and the dura mater without damaging the brain in a non-propelled and depth-controlled manner. Then, a second catheter may be used to atraumatically advance the first catheter through one or more of the subdural and epidural spaces and into the SDH for drainage. Once the viscous fluid of the SDH is emptied, a second catheter or a third catheter may be used to occlude the arteriotomy formed by the first catheter without bleeding. Some surgical systems in the surgical system described herein may be used to perform surgical procedures including one or more of surgical evacuation, embolization, drug or biological delivery, device delivery (e.g., including electrodes), tissue sampling, and combinations thereof.

[0061] In some embodiments, a method may include positioning a distal end of a catheter disposed within an intracranial blood vessel of a subject near a target location; and advancing a shaft through the lumen of the catheter such that a curved segment of the shaft bends in a direction along the curve of the blood vessel. For example, the curved segment may be constrained within the lumen of the catheter. The curved segment of the shaft may extend beyond the distal end of the catheter such that the curved segment bends toward the wall of the blood vessel and an RF element disposed at the distal end of the shaft is positioned against the wall of the blood vessel. The RF element may be activated to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the blood vessel of the subject and into an extravascular intracranial cavity. The distal end of the shaft may be advanced into the extravascular intracranial cavity until the curved segment transitions to an unconstrained configuration within the extravascular intracranial cavity. The catheter may be advanced over the shaft and into the extravascular intracranial cavity.

[0062] In some embodiments, a device may include a shaft configured to be slidably disposed within the lumen of a catheter. The shaft 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 shaft may include a perforated tip comprising an energy element configured to generate RF energy to form an opening through the wall and dura mater of the subject's blood vessel and into the subject's extravascular lumen. A curved section of the shaft may be configured to be radially constrained within the lumen of the catheter. The curved section may be configured to bend toward the wall and dura mater of the blood vessel upon exiting the lumen of the catheter, such that the energy element is positioned to form the opening. A first discontinuity may be disposed between the perforated tip and the curved section, and a second discontinuity may be disposed proximal to the curved section. The second discontinuity is configured to orient the shaft to follow the curve of the blood vessel as it is advanced within the lumen of the catheter.

[0063] In some embodiments, a system may include a catheter having a proximal end and a distal end, and defining a lumen between the proximal end and the distal end. The distal end of the catheter may be configured to be positioned within a blood vessel of a subject. A shaft may be slidably positioned within the lumen. The shaft may include a perforated tip having an energy element configured to generate RF energy to penetrate the wall and dura mater of the blood vessel of the subject. The shaft may also include a bending section configured to transition from a radially constrained configuration to a curved configuration. The shaft may be configured to be advanced along the catheter such that the bending section is oriented to bend along the curve of the blood vessel and away from the distal end of the catheter. The bending section may be configured to bend toward the wall of the blood vessel such that the perforated tip is positioned against the wall of the blood vessel and, when the energy element is activated, can penetrate the wall of the blood vessel and the dura mater and enter the extravascular lumen. Other suitable examples of systems, devices, and methods are described in international application serial number PCT / US2021 / 029276, filed on April 27, 2021, the disclosure of which is incorporated herein by reference in its entirety.

[0064] The systems, devices, and methods described herein can be used to access an extravascular space of a subject, including, for example, an intradural extravascular space along the spinal cord of a subject or in the brain of a subject. Figure 1 is a schematic coronal cross-sectional view of a subject 100 including a skull 110 enclosing each of a brain 120, the dura mater (dura mater) 130, the superior sagittal sinus (SSS) 140, and a subdural hematoma (SDH) 150. An SDH is a type of hemorrhage in which an effusion of blood, typically associated with a traumatic brain injury, collects between the inner layer of the dura mater and the arachnoid membrane of the meninges that surround the brain. The SDH is typically caused by a tear in a bridging vein that passes through the subdural space, followed by ongoing bleeding from microvessels. A subdural hematoma can lead to increased pressure within the skull, which in turn can lead to compression and destruction of delicate brain tissue. The SDH 150 is Figure 1 It is depicted between the brain 120 and the dura mater 130 and generally faces the convex surface of the cerebral hemispheres. Figure 1 Not shown, the SDH may be located near the vascular structures of the dura mater 130, including the middle meningeal artery (MMA), the middle meningeal vein (MMV), the superior sagittal sinus (SSS) 140, the inferior sagittal sinus (ISS), the superior petrosal sinus (SPS), and the transverse-sigmoid junction or transverse sinus (TS).

[0065] The SSS140 is a valveless midline vein that extends along the falx cerebri from near the coronary artery to the sinus confluence at the posterior cranial fossa. The SSS140 faces both cerebral hemispheres and typically has a length between about 31 cm and about 38 cm and receives between about 12 and about 20 venous branches from the left and right cerebral hemispheres. Typically, the SSS140 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 SSS140 may be between about 15 mm and about 20 mm. 2 About 90mm 2 The angle between the sinus wall and the midline can be between about 25° and about 65°. The typical distance between the SSS 140 and the subdural hematoma 150 is generally less than about 35 mm. The SSS 140 is generally surrounded by the dura mater 130 and is separated from the brain 120 by the arachnoid mater and the subarachnoid space, which are filled with cerebrospinal fluid. Brain atrophy may cause the space between the SSS 140 and the brain 120 to widen. For example, in subjects with chronic SDH, the space between the surface of the brain 120 and the dura mater 130 may be between about 1 mm and about 20 mm (e.g., between about 2 mm and about 8 mm).

[0066] A brief discussion of conventional approaches used to treat subdural hematomas may be further helpful. Figure 2 A schematic perspective view 200 of a subject undergoing surgical evacuation of a hematoma is depicted. In particular, a first burr hole 210 and a second burr hole 212 are formed in the subject's skull near a hematoma 230 that is located at Figure 2 Saline solution 220 can be introduced into the first burr hole 210 so that fluid 232 (including hematoma 230) can flow out of the second burr hole 212.

[0067] In some embodiments, a single intravascular approach may be performed to gain access to the extravascular lumen of a subject. For example, Figures 3A to 3D are side and cross-sectional views of a subject's head 300 , 302 , 304 , 306 . Figure 3A300 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., cannula, delivery catheter, guide catheter, intermediate catheter) 360 can be advanced through one or more of the internal maxillary artery 340 and the MMA 342. A catheter 362 (e.g., an embolization catheter) can be advanced from the distal end of the sheath 360 and configured to deliver a hemostatic element 370 (e.g., an occlusive element, an embolic material, an embolic fluid, microparticles, a coil) to a set of branches of the MMA 342 for reducing bleeding from one or more branch vessels of the MMA 342. In some embodiments, the sheath 360 can 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., carpal artery), brachial artery, carotid artery, etc.

[0068] The MMA 342 is typically the third branch of the first portion of the internal maxillary artery 340. Each side of the head may include an MMA 342 that branches from the internal maxillary artery 340 in the infratemporal fossa, passes through the foramen spinosum, and enters the intracranial compartment, wherein the MMA 342 deviates anteriorly and laterally at an angle of between about 60° and about 120° relative to the longitudinal axis of the foramen spinosum.

[0069] like Figures 3B to 3D As shown, the MMA 342 is typically located on the lateral side of the dura mater 330. The MMA 342 typically bifurcates parallel to the dura mater 330. The MMA 342 can supply blood to the dura mater 330, the outer layer of the meninges, and the calvaria. The main trunk of the MMA 342 can typically be between about 14 mm and about 34 mm. The MMA 342 typically bifurcates into frontal and parietal branches (and other small branches). The average diameter of the main trunk of the MMA 342 can be between about 0.6 mm and about 1.2 mm. However, subjects with cSDH may have an average 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 SDH. Figure 3C A catheter 362 and a shaft 364 are depicted being advanced into the MMA 342 between the dura mater 330 and the skull 310. The shaft 364 can be configured to be slidably disposed within the lumen of the catheter 362. As described in greater detail herein, the shaft 364 can be configured to form an opening through the wall of a blood vessel (e.g., the MMA 342) and the dura mater 330 and into the extravascular lumen of the subject to facilitate access to the intradural space between the dura mater 330 and the brain 320. Figure 3D Depicted is the delivery of a hemostatic element 370 into the MMA 342 via a catheter 362 .

[0070] Figure 4A and Figure 4B are X-ray images 400, 402 of arterial blood flow in a subject's head. For example, Figure 4A Blood flow through the middle meningeal artery (MMA) 410 is shown, and Figure 4B Blood flow through the MMA 410 after occlusion of the MMA 410 is shown. Figure 4C is an X-ray image 404 of a subject's head with two burr hole locations 420 connected to the cranium and a catheter 430 disposed within an MMA 410 .

[0071] I. System

[0072] The systems and devices described herein can be configured to enable transvascular procedures, including but not limited to improving access to the extravascular lumen, treating subdural hematomas, delivering drugs or therapeutic agents, delivering devices (e.g., sensors, electrodes, biopsy devices, ablation devices, catheters, drainage systems), tissue sampling, implanting devices, etc. Figure 5 5 is a schematic block diagram of a system 500 comprising a catheter assembly 502, a vacuum source 550, a signal generator 560 and a visualization device 570. The catheter assembly 502 can be configured to form an opening between a blood vessel and the extravascular cavity of a subject. In some embodiments, the catheter assembly 502 can comprise a catheter 510, a shaft 520, a hemostasis device 530, one or more optional sensors 540 and an optional sheath (e.g., a delivery catheter, a guide catheter) (not depicted).

[0073] 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 roads, a bundle, a tube (having one or more lumens), a strand, a cable (two or more wires running side by side, bonded, twisted, or braided), a coil, a braid, combinations thereof, etc. In some embodiments, one or more components of the catheter assembly 502 may include one or more of stainless steel, nitinol, silver, titanium, copper, cobalt chromium, nickel chromium, platinum iridium, polymers, nylon, polyamides, fluoropolymers, polyolefins, polytetrafluoroethylene, high-density polyethylene, polyurethanes and polyimides, ceramics, bioabsorbable or dissolvable materials, combinations thereof, etc.

[0074] In some embodiments, one or more components of the catheter assembly 502 may have a flow rate between about 0.0002 lb / in. 2 and about 0.15 lb / in 2 , including all ranges and subvalues ​​therebetween. The components of the catheter assembly 502 can have variable tip bending stiffness along the respective length of each component.

[0075] In some embodiments, one or more components of the catheter assembly 502 may include scores configured to increase flexibility (e.g., to pass through the curve of the foramen spinosum). Scores may include, but are not limited to, spiral score patterns (e.g., continuous, discontinuous), radial score patterns, custom score patterns, radial ring patterns, longitudinal scores, angled scores, windows, tabs, holes, combinations thereof, and the like.

[0076] In some embodiments, one or more components of the catheter assembly 502 can have cross-sectional shapes including, but not limited to, circular, oval, square, star-shaped, diamond-shaped, rectangular, flat, combinations thereof, and the like.

[0077] catheter

[0078] Conduit 510 can be configured to remove fluid from the extravascular cavity and / or fluid or equipment are delivered to the extravascular cavity.In some embodiments, catheter assembly can be enough little and flexible to navigate in the cranium by crossing over a plurality of complex angles, and has high and accurate torsional property to guide perforation towards the subdural space from the far entry site exceeding approximately 170cm.These challenges aggravate due to the variation of experimenter, and these variations comprise the degree of aorta and meningeal-neck blood vessel curvature, the position of the arterial perforation point along the temporal bone squama, fluid viscosity and the existence of thick film and diaphragm.

[0079] In some embodiments, the catheter 510 can be slidably disposed within the lumen of a sheath. For example, the sheath can include one or more of a guide catheter (e.g., a 5F Asahi Fubuki guide catheter), an intermediate delivery catheter (e.g., a DAC 044, Stryker), and a microcatheter (e.g., a 0.027" Phenom 27 microcatheter, Medtronic).

[0080] The catheter 510 can be designed to be highly flexible. In some embodiments, the catheter 510 is flexible enough to assume the shape of the shaft 520 slidably disposed therein. However, the shape of the catheter 510 and the shaft 520 may be constrained by the shape of the lumen or body cavity (e.g., an artery, the subdural space) in which the catheter is disposed.

[0081] In some embodiments, the catheter assembly can be configured to prevent catheter protrusion, catheter ovalization, and catheter sticking against the opening during advancement. Additionally, the catheter can be configured to remain patent without kinking when the shaft is retracted and not collapse when negative suction is applied through the lumen of the catheter.

[0082] In some embodiments, the inner diameter of the catheter can be maximized while ensuring navigation of the catheter through the intracranial vessels to the perforation site. For example, for a perforation site in an MMA, the catheter 510 can have a distal inner diameter between about 0.005 inches and about 0.060 inches and between about 0.012 inches and about 0.03 inches, including all ranges and subvalues ​​therebetween.

[0083] In some embodiments, the catheter configured to reach the radial and / or femoral entry points can have a working length of at least about 120 cm and between about 140 cm and 160 cm, including all ranges and subvalues ​​therebetween. In some embodiments, the catheter 510 can be configured to advance through a minimum bend angle of 70° without kinking to facilitate advancement through the foramen spinosum into the intracranial cavity.

[0084] In some embodiments, the catheter 510 has sufficient column strength to generate a forward load greater than about 1 N to perforate the MMA and dura without kinking, ovalizing, or protruding into a vessel (e.g., a branch artery), and to receive a negative pressure greater than about 29 inHg for fluid removal without collapsing.

[0085] The catheter 510 can define a lumen (with a corresponding inner diameter) extending from a proximal end to a distal end of the catheter 510. In some embodiments, the inner diameter and / or outer diameter of the catheter 510 can be tapered. In some embodiments, the inner diameter at the distal end of the catheter 510 can be smaller than the inner diameter at the proximal end of the catheter 510, e.g., to facilitate increased fluid flow (e.g., during aspiration).

[0086] In some embodiments, the distal end of the catheter 510 can include a radiopaque element. The radiopaque element can be configured to facilitate alignment between the distal end of the catheter 510 and a feature of the shaft (e.g., a wider or larger region of the shaft to prevent ovalization), as further described below.

[0087] In some embodiments, the catheter can include multiple lumens and one or more distal openings. In some embodiments, one or more of the lumens can be configured for aspiration and / or fluid injection. For example, the catheter can be configured to inject non-ionic glucose during RF energy delivery to reduce current leakage, thereby improving vaporization efficiency of the target tissue.

[0088] In some embodiments, the catheter can be configured to minimize, prevent and / or process catheter occlusion, and the catheter includes a slidable element and a deployable element. For example, the catheter may include two telescopic hypotubes. The outer catheter (e.g., proximal hypotube) may have an inner diameter sufficient to accommodate an inner catheter (e.g., distal hypotube) that is advanced using, for example, a push wire. These inner hypotubes and outer hypotubes may include one or more tapers to gradually reduce the gap between the inner hypotube outer diameter and the outer hypotube inner diameter until there is no significant gap left for the predetermined section of the catheter. The predetermined section may be configured to form a seal that maximizes cross-section and attraction and flow. In addition, the double hypotube catheter may have the following advantages: utilizing the catheter to obtain flow occlusion in intraosseous or extracranial MMA while providing a lumen for use in MMA and by performing distal instrumentation via vascular access.

[0089] In some embodiments, the catheter 510 may include a proximal segment configured for navigation, which is coupled to a distal segment defining a lumen. For example, the proximal segment may be configured to control translation (e.g., longitudinal bidirectional movement, pushing, pulling) of the catheter 510 through a blood vessel. In some embodiments, the proximal segment may not have a lumen to assist in pushability. For example, the proximal segment may include a hypotube, a single solid rod, a wire (e.g., having one or more cross-sectional shapes including circular, flat, square, or diamond), a plurality of tracts, bundles, one or more tubes (having one or more lumens), a plurality of shaft strands, cables (e.g., two or more wires extending side by side, bonded, twisted, or braided), a coil, a braid, a wire (e.g., circular, flat, square, or diamond), a combination thereof, or the like. The distal segment may include a second catheter defining a lumen, which is configured to receive one or more of an axis 520, negative pressure, SDH, a hemostasis device 530, or the like. The proximal segment may have a diameter smaller than that of the distal segment. In some embodiments, the distal segment of catheter 510 can have a length between about 7 cm and about 20 cm.

[0090] In some embodiments, the proximal portion of the distal segment may have an outer diameter that substantially matches the inner diameter of the distal portion of the sheath, such that the distal segment can be coupled to the sheath via a friction fit. In some embodiments, the distal segment includes a proximal portion having an outer diameter that tapers from a first outer diameter that is substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion is configured to limit the length to which the distal segment can be advanced distally beyond the distal end of the sheath. In some embodiments, the inner diameter of the distal end of the sheath can be gradually and / or gradually incremented to decrease or narrow. Thus, the catheter 510 can be advanced through the sheath until the proximal portion of the distal segment of the catheter 510 abuts the distal portion of the sheath at a "sealing zone" where the inner diameter of the sheath substantially matches the outer diameter of the catheter 510.

[0091] Figure 28 A coronal cross-sectional view 2800 of a catheter assembly disposed within an MMA 2810 in a subject's head is depicted. The catheter assembly can include a sheath 2820 and a catheter 2830 disposed within the lumen of the sheath 2820. The catheter 2830 can include a proximal segment 2840 (e.g., a pushwire) coupled to a distal segment 2850 defining the lumen. A proximal portion 2852 of the distal segment 2850 can have an outer diameter that substantially matches the inner diameter of the distal portion of the sheath 2820, such that the distal segment 2850 can be coupled to the inner diameter of the sheath 2820 via a friction fit. In some embodiments, the distal segment 2850 includes a proximal portion 2852 having an outer diameter that tapers from a first outer diameter that is substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion 2852 is configured to limit the length to which the distal segment 2850 can be distally advanced beyond the distal end of the sheath 2820. The proximal segment 2840 can be coupled to the inner diameter of the proximal portion 2852 of the distal segment 2850 .

[0092] In some embodiments, the outer diameter of the proximal portion 2852 of the distal segment 2850 of the catheter 2830 can be between about 0.001 inches and about 0.005 inches smaller than the inner diameter of the distal end of the sheath 2820 to form an airtight seal. When the distal segment 2850 and the sheath 2820 are coupled via a friction fit, negative pressure applied through the sheath 2820 can propagate through the catheter 510 and facilitate drainage of the SDH. Additionally, the inner diameter of the distal segment 2850 can be smaller than the inner diameter of the sheath 2820 to promote a higher flow rate through the catheter assembly when negative pressure is applied through the sheath (e.g., based on the Hagen-Poiseulle equation).

[0093] axis

[0094] Axis described herein can be configured to meet the requirements of one group of complexity.In some embodiments, catheter assembly can be navigated through MMA in cranial cavity and has axis, and this axis is configured to self-orient in MMA for forming opening in MMA and dura mater in the correct direction (for example, away from skull), and indicates axis to operator and has completed self-orientation.For example, for middle meningeal artery enters through blood vessel, the combination of relative curve (for example, proximal curve, distal curve) along the different sections of axis can be configured to cause axis rotation (for example, self-orientation), with the proximal curve of axis aligned with the curvature of foramen spinosum and middle cranial fossa (for example, outer concave surface), and the distal curve of axis aligned with the curve of cranial fossa and skull top (for example, inner concave surface).

[0095] The shaft can be configured to form a transvascular opening having a length, width, and / or diameter sufficient to allow passage of a catheter, such as catheter 510 described above (e.g., an aspiration catheter, a 0.027" microcatheter). The opening can be circular, oval, or longitudinal (e.g., a slit).

[0096] In some embodiments, the shaft 520 may be coupled to a signal generator 560. As described in more detail herein, the shaft 520 may include a distal end portion 522 having a perforating element 524 configured to create (e.g., form) an opening in the wall and dura mater of a subject's blood vessel. For example, the shaft may be configured to form a transvascular passage into the subdural space using electrocautery. In some embodiments, the shaft 520 may also include an offset 526 (e.g., a discontinuity, a bend) configured to orient a predetermined portion of the shaft 520 in a predetermined orientation as the shaft 520 is advanced within the lumen and blood vessel of the catheter 510. The shaft 520 may include multiple portions having one or more different diameters, shapes, hardnesses, and the like. For example, a multi-hardness shaft 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 to provide proximal stiffness and gradually decreasing distal stiffness.

[0097] In some embodiments, the shaft can be configured to prevent the ovalization of the catheter, thereby preventing the catheter from getting stuck against the opening formed by the shaft. For example, the space between the inner diameter of the catheter and the outer diameter of the shaft (e.g., a difference, a step (shelf)) may cause the catheter to be compressed into an oval shape, which may increase the possibility of the catheter getting stuck against the edge of the tissue opening (e.g., a slit), thereby preventing the catheter from being advanced outside the MMA and into the subdural space. In some embodiments, the shaft can be configured so that the predetermined portion of the shaft can have an outer diameter similar to (e.g., substantially equal to) the inner diameter of the predetermined portion of the catheter, so that the step between the shaft and the catheter can be ignored, so that the catheter can maintain a circular (e.g., non-elliptical) cross-sectional shape along a predetermined length, so as to pass through the formed tissue opening. For example, the outer diameter or maximum lateral dimension of the shaft can be increased at the position of a reference or radiopaque marker. As described above, before the catheter is advanced through the opening in the vessel wall or dura mater together with the shaft, the radiopaque marker on the shaft can be aligned with the radiopaque marker on the distal end of the catheter. The larger size of the shaft at this location prevents the catheter from ovating as it is advanced through the opening while minimally impacting the overall increase in friction that would be achieved by the negligible step between the shaft and the catheter along the longer segment. The relatively high overall friction between the shaft and the catheter may prevent rotation (e.g., self-orientation) of a shaft used for directional perforation into the subdural space as described herein.

[0098] In some embodiments, the shaft can be configured to prevent extravasation of fluids. For example, the shaft can include one or more of a taper, a localized expansion of the outer diameter, a surface modification, an expandable element, and the like.

[0099] In some embodiments, the shaft 520 may have a predetermined shape at a predetermined portion (e.g., at a focal point along the length of the shaft) that is configured to divert the advancing catheter away from the edge of the dura mater at the site of the arteriotomy / dura mater incision. In some embodiments, the predetermined shape may include one or more of a J-shape, a U-shape, a C-shape, a V-shape, an M-shape, an S-shape, a spiral, and combinations thereof. For example, the shape may form a mountain shape that is configured to force the edge away from or lift the dura mater.

[0100] In some embodiments, the shaft 520 may comprise a shape memory material (e.g., Nitinol) wire having a polymer jacket. As described in more detail herein (e.g., Figure 6 8 ), the shaft may include a flattened (e.g., compacted) portion configured to self-orient within the intracranial MMA. As described in greater detail herein, different shaft shapes and configurations (e.g., J-curves, curves and reverse curves, bends, offsets, diameter variations) may improve flexibility, pushability, and support.

[0101] In some embodiments, the shaft can be formed with a set of constant diameter distal and proximal segments having varying diameters between approximately 0.014 inches and 0.027 inches, including all ranges and subvalues ​​therebetween.

[0102] In some embodiments, the shape memory material of the shaft can have a proximal diameter of about 0.010 inches and about 0.025 inches, including all ranges and subvalues ​​therebetween. In some embodiments, the shape memory material of the shaft can have a tapered distal diameter of about 0.0060 inches and about 0.014 inches, including all ranges and subvalues ​​therebetween.

[0103] In some embodiments, the distal segment of the shape memory material can be flattened to a width of between about 0.008 inches and about 0.018 inches, including all ranges and subvalues ​​therebetween. In some embodiments, the distal segment of the shape memory material can have a thickness of between about 0.003 inches and about 0.008 inches, including all ranges and subvalues ​​therebetween.

[0104] In some embodiments, the shaft can be configured to be slidably disposed within the lumen of a catheter. The shaft can be configured to be advanced distally from the distal end of the catheter and into a subject's blood vessel (e.g., MMA). The shaft can include a perforated tip that includes an energy element. The energy element can be configured to generate RF energy to form an opening that passes through the wall and dura mater of the subject's blood vessel and enters the subject's extravascular cavity. A curved segment can be configured to be radially constrained within the lumen of the catheter. The curved segment can be configured to bend toward the wall and dura mater of the blood vessel when leaving the lumen of the catheter, so that the energy element is positioned to form the opening. A first discontinuity can be provided between the perforated tip and the curved segment. A second discontinuity can be provided proximal to the curved segment. The second discontinuity is configured to orient the curve to follow the curve of the blood vessel when the shaft is advanced within the lumen of the catheter.

[0105] In some embodiments, the first discontinuity can comprise a bend in the shaft. In some embodiments, the curved segment can have a first radius of curvature, and the first discontinuity comprises a segment of the shaft having a second radius of curvature that is smaller than the first radius of curvature. In some embodiments, the curved segment can be configured to transition into a curved configuration as the curved segment travels through the opening and into the extravascular lumen.

[0106] In some embodiments, the curved section may have a cross-section having a first lateral dimension that is greater than a second lateral dimension. In some embodiments, the second discontinuity may comprise a bend in the shaft. In some embodiments, the second discontinuity may comprise a partial spiral or twist in the shaft. In some embodiments, the curved section may have a first curved section comprising a convex curvature, and the shaft may further comprise a second curved section proximal to the first curved section. The second curved section may comprise a concave curvature. In some embodiments, the shaft may comprise a wider section having a lateral dimension that is equal to or substantially equal to the inner diameter of the lumen of the catheter to prevent ovalization of the catheter as the catheter is advanced through the opening. In some embodiments, the length of the opening is equal to or substantially equal to the length of the energy element.

[0107] In some embodiments, the shaft can include a first radiopaque element disposed at the perforated end and a second radiopaque element disposed proximal to the curved section. The shaft can also include a wider section disposed proximal to the curved section. For example, as described above, the wider section can be configured to prevent ovalization of the catheter as the catheter is advanced into the extravascular cavity. The distal end of the catheter can include the first radiopaque element, and the shaft can include a second radiopaque element disposed proximal to the wider section so that the wider section can be aligned with the distal end of the catheter before the catheter is advanced into the extravascular cavity.

[0108] In some embodiments, the shaft may include one or more lumens having one or more openings. One or more lumens may be configured for one or more of fluid injection and suction (e.g., for connection). For example, injecting non-ionic glucose through a first lumen during RF energy delivery can reduce or eliminate alternative current paths and achieve more efficient vaporization of target tissue. The second lumen may be configured to provide suction (e.g., suction) to improve wall adhesion with the RF electrode and / or collapse the arterial vessel during RF-mediated arterial occlusion. In some embodiments, the proximal end of the shaft may be connected to a signal generator (e.g., an RF generator) via a button-type electrosurgical pencil.

[0109] distal end

[0110] In some embodiments, the perforating element 524 of the shaft 520 can include an electrode (e.g., an RF ablation tip). Using the electrode to deliver RF energy can rapidly increase tissue temperature to convert fluid into vapor (e.g., vaporization), thereby causing local tissue disruption and cavitation. Vaporization can create fenestrations from the vessel lumen (and through the dura mater) to the intradural space.

[0111] In some embodiments, the penetration presented by the dura mater is realized with mechanical (e.g., cutting) elements. It may be necessary to have a needle penetration force between 0.29N and 1.29N (0.68 ± 0.24N) to penetrate the dura mater, because the dura mater is a very tough tissue that requires both high acuity and strong penetrating force. However, a sharp needle tip may cause the catheter to scrape or scrape along the bend and unexpected brain perforation. In addition, high penetrating force requires high catheter column strength and pushability, which are obtained by using rigid materials and structures, and these rigid materials and structures are opposite to the strength and pushability requirements for navigating the catheter through tortuous blood vessel geometry. In some embodiments, the distal end portion 522 of shaft 520 can (e.g., when the distal end of shaft 520 is attached to the distal end of the distal end portion 522 about 5mm, about 10mm, and about 20mm) have a terminal bending stiffness between about 0.5gf and about 15gf, including all ranges and subvalues ​​therebetween.

[0112] RF tissue ablation without mechanical cutting can allow the shaft 520 to have a reduced column strength compared to mechanical cutters such as needles that require high pushability. In addition, the atraumatic perforating element can be less likely to damage the catheter 510 relative to a shaft with a needle tip. Ablation of tissue that produces cavitation can also reduce edge entrapment when the catheter 510 is advanced through a tissue opening. In some embodiments, the distal portion of the shaft 520 (e.g., up to about 300 mm from the distal end portion 522) can 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, including all ranges and subvalues ​​therebetween.

[0113] In some embodiments, RF energy can be used to facilitate perforation of septa associated with mixed-age SDH and chronic SDH, and dredging of catheters through one or more of the surrounding membranes into a hematoma. Additionally, RF energy can be used to coagulate tissue to facilitate one or more of formation and closure of tissue openings.

[0114] In some embodiments, the perforated element 524 may include two or more electrodes. For example, the perforated element 524 may include two or more tubular elements. In some embodiments, a plurality of electrodes may be individually connected in parallel to the signal generator 560 in a monopolar configuration and share the same ground pad. In another embodiment, in a bipolar configuration, a first electrode may be connected to the signal generator 560 and a second electrode may be connected to the ground. In the bipolar configuration, current may be concentrated between the first electrode and the second electrode.

[0115] In some embodiments, in a bipolar configuration, the perforating element 524 can include a first electrode and the catheter 510 can include a second electrode. In this configuration, the perforating element 524 and the catheter 510 can be advanced concurrently to maintain current delivery to the tissue, or the perforating element 524 can be advanced relative to the catheter 510 to reduce current delivery and reduce the likelihood of brain damage as the tissue collapses.

[0116] In some embodiments, the perforating element 524 may include platinum iridium, stainless steel, copper, titanium and nickel titanium alloy, and is constructed as a fluoroscopic marker and RF electrode. 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 comprising one or more of a bullet shape, a cone shape, a truncated cone shape, a cylinder shape, a sphere shape, a dome shape, an annular shape, a semi-annular shape, an elliptical shape, an inclined plane and an arrow shape. In some embodiments, the electrode of the perforating element 524 may be uninsulated or partially insulated and may be made of and / or coated with a conductive and biocompatible material with high radiopacity (such as stainless steel, silver, gold, platinum, a combination thereof, etc.). In such embodiments, the shaft may be covered with an insulating material along its length, wherein the electrode is uninsulated or covered in a conductive material at its distal end. In some embodiments, the uninsulated portion of the perforating element 524 may have a diameter less than about 16 mm. 2 , between about 1mm 2 With about 5mm 2 In some embodiments, the energy delivery portion of the perforating element 524 may have a length between about 1.3 mm and about 1.7 mm, including all ranges and subvalues ​​therebetween. In some embodiments, the perforating element 524 may be configured to deliver a power between about 10 watts and about 100 watts, including all ranges and subvalues ​​therebetween. In some embodiments, the perforating element 524 may be configured to deliver a power between about 1200 A / m 2 and about 12000A / m 2 Between, about 2000A / m 2 About 10000A / m 2 Between, about 2000A / m 2 About 5000A / m 2 Between, about 5000A / m 2 About 10000A / m 2 Between, about 1200A / m 2 and about 6000A / m 2 Between, about 8000A / m 2 and about 12000A / m 2 In some embodiments, the perforated element 524 can be configured to deliver a current density between about 10 watts and about 100 watts, between about 20 watts and about 75 watts, including all ranges and subvalues ​​therebetween. In some embodiments, the distal end of the perforated element 524 can be open or closed. In some embodiments, the perforated element can be tapered.

[0117] Hemostasis equipment

[0118] In some embodiments, the hemostatic device 530 includes a hemostatic element or RF device configured to close the opening formed by the perforating element 524 of the shaft 520. The hemostatic device 530 can optionally be coupled to a signal generator 560. In some embodiments, the catheter 510 can be configured to deliver the hemostatic device 530 to the location of the opening through the vessel wall and / or dura mater (e.g., to seal the opening).

[0119] Linear RF devices

[0120] In some embodiments, shaft assemblies, such as shaft 520 and shaft assembly 900, include a linear tip RF device (e.g., shaft 920) configured to create an opening in a vessel wall and / or dura mater to access, for example, the epidural and / or subdural space. The linear tip RF device may have a shaft and a distal tip portion coupled to the shaft, wherein the longitudinal axis of the shaft is parallel to the 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 facilitate distal access to the subdural space and underlying tissue. The linear tip RF device may be configured to deliver one or more of energy and / or mechanical force between bone and tissue (e.g., vessel wall, dura mater) to create an opening within a vessel or between the epidural and subdural spaces. For example, the energy may include one or more of RF energy, pulsed field ablation, microwaves, diathermy, laser, electrocautery, and cryogenic energy. In some embodiments, the mechanical force may include one or more of cutting, stretching, compression, bending, deformation, and shearing.

[0121] In some embodiments, one or more portions of the shaft can have a cross-section having a first lateral dimension that is greater than a second lateral dimension. In some embodiments, the shaft can include a wider section having a lateral dimension that is equal to or substantially equal to the inner diameter of the lumen of the catheter to prevent ovalization of the catheter as the catheter is advanced through the opening and to facilitate bending of the shaft in a first plane and to constrain bending in a second plane perpendicular to the first plane.

[0122] In some variations, the diameter of the linear tip RF device may be similar to the diameter of the blood vessel to be perforated. In some embodiments, the linear tip RF device can be advanced into the subdural space in a trajectory substantially parallel to the surface of the dura mater and / or the surface of the brain 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 is capable of penetrating the membrane of a subdural hematoma. This may facilitate the entry and exit of a catheter (e.g., a suction catheter) into and out of the 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 the vascular lumen of a blood vessel. For example, when the catheter has been retracted from the extravascular lumen and entered into a blood vessel (e.g., an MMA), the second RF device can be used to seal the opening formed in the MMA. Thus, the second RF device can be used as a hemostatic device.

[0123] In some embodiments, the linear RF device can be configured in a monopolar or bipolar configuration, a single or multiple bipolar configuration. In some embodiments, the linear RF device can have a shape corresponding to a ring or coil configuration for circumferential thermal ablation. In some embodiments, the coil configuration can be provided at the distal end of the linear RF device and have a length between about 3 mm and about 30 mm and a diameter between about 0.01 inches and about 0.05 inches, including all ranges and subvalues ​​therebetween. In some embodiments, the diameter can be continuous or tapered.

[0124] In some embodiments, the linear RF device can include a temperature sensor, such as a thermistor and a thermocouple. In some embodiments, the temperature sensor can be thermally isolated from the RF electrode.

[0125] sensor

[0126] In some embodiments, one or more sensors 540 may be coupled to one or more of the catheter 510, the shaft 520, and the hemostasis device 530. The 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 the operator and the signal generator during the procedure. For example, pressure measurements may indicate to the operator the position and / or orientation of the shaft 520 of the catheter assembly 502, while RF energy may be delivered to the perforating element 524 only when the measured impedance is within a predetermined range to prevent damage to brain tissue.

[0127] In some embodiments, the pressure sensor may include 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 microelectromechanical system pressure sensor, and a piezoelectric pressure sensor. For example, the piezoelectric pressure sensor may include a piezoelectric film disposed along the outer diameter of the perforating element near the distal end. The measured signal may include a peak pressure value associated with penetration of the MMA wall, followed by a pressure drop associated with entry into the subdural space. In some embodiments, the pressure sensor may be configured to measure a pressure waveform (e.g., an arterial waveform, an intracranial waveform, or a venous perforation waveform) upon penetration from the vascular lumen into the intracranial chamber. In some embodiments, tissue spectral values ​​may be measured to monitor perforation and entry into the subdural space.

[0128] In some embodiments, a first pressure sensor may be provided at or adjacent to the distal end of the perforating element and configured to measure pressure on tissue and / or fluid. A second pressure sensor may be provided proximal to the first pressure sensor (e.g., approximately 0.2 mm and approximately 2 mm from the first pressure sensor). The first pressure sensor measurement and the second pressure sensor measurement when the puncture element is advanced through the blood vessel correspond to the nominal blood pressure. When the perforating element contacts the wall of the blood vessel, the first pressure sensor measurement corresponding to the blood 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 an opening is formed in the blood vessel wall, the first pressure measurement and the second pressure measurement may correspond to the fluid pressure of the subdural space.

[0129] In some embodiments, the impedance sensor can be configured to measure the impedance, dielectric constant and / or conductivity of tissue and fluid to monitor perforation and entry into the subdural space. Changes in the impedance (or other dielectric properties) between the artery, dura mater, fluid (e.g., contrast agent, cerebrospinal fluid, subdural hematoma), intradural space and brain can indicate the position of the perforating element throughout the procedure. Impedance measurement can be used to control the energy delivery performed by the signal generator. For example, energy delivery can be modified to optimize cutting and stopped based on the measured impedance.

[0130] In some embodiments, the temperature sensor can be configured to measure the temperature of tissue and fluid. For example, the temperature sensor can include a thermocouple arranged at the distal end of the perforated element or adjacent to the distal end of the perforated element. The measured temperature can be used to control the waveform delivery (e.g., impedance, voltage, duty cycle, pulse width) performed by the signal generator. For example, if the measured temperature exceeds a predetermined threshold, energy delivery can be modified to optimize and cut and be stopped to prevent unexpected tissue damage.

[0131] In some embodiments, the perforating element 524 (e.g., an electrode) can be configured to measure electroencephalogram (EEG) signals disposed within approximately 20 mm of the distal end of the perforating element 524. The perforating element 524 can be configured to alternately deliver RF energy and measure EEG signals, impedance signals, etc.

[0132] In some embodiments, a force sensor disposed on or adjacent to the perforating element can be configured to measure the force associated with the shaft penetrating the MMA and the dura. For example, pressure can be measured using a pressure transducer disposed externally to the subject.

[0133] vacuum source

[0134] In some embodiments, a vacuum source 550 can be coupled to the catheter 510. The vacuum source 550 can be configured to provide negative pressure (e.g., suction) to the lumen of the catheter 510. The suction generated by the vacuum source 550 can be configured to remove fluids and substances (e.g., from a subdural hematoma) through the lumen of the catheter 510. In some embodiments, the vacuum source can include one or more of a pump and a syringe. The vacuum source 550 can be configured to operate in one or more modes, including continuous, dynamic, cyclic, pulsatile, low frequency, high frequency, combinations thereof, and the like.

[0135] Signal Generator

[0136] Typically, the signal generator described herein can be configured to provide energy (e.g., energy waveform) to form an opening in tissue to the perforating element. In some embodiments, the signal generator 560 can be coupled to one or more of the shaft 520 and the hemostasis device 530. In particular, the signal generator 560 can be configured to generate energy for delivering the perforating element 524 using the distal end portion 522. The signal generator 560 may include a processor 562, a memory 564, and an input / output device 566, which are configured to control the signal generator 560 and provide an appropriate energy waveform for tissue ablation, and ensure patient safety. In some embodiments, the signal generator can be configured to control waveform generation and delivery in response to received sensor data. For example, energy delivery can be prohibited unless the impedance sensor measurement confirms the tissue type to be ablated.

[0137] The signal generator can generate and transmit several types of signals, including but not limited to RF, pulsed field ablation, microwave, diathermy, laser and electrocautery. For example, diathermy waveforms, laser waveforms and electrocautery waveforms can be used to cut and / or coagulate the membrane surrounding a subdural hematoma, the diaphragm inside the hematoma, or any bleeding source. Diathermy, laser and electrocautery waveforms can also be used to close transvascular channels and vascular lumens, such as MMA. In some embodiments, monopolar or bipolar electrocautery can be separated from or integrated with the catheter and / or shaft. In some embodiments, one or more of the shaft and catheter can be combined with thermal ablation. For example, the signal generator can generate monophasic (DC) pulses and biphasic (DC and AC) pulses. The signal generator may include a processor, a memory, an energy source and a user interface. The processor may be incorporated with data received from one or more of the memory, energy source, user interface and catheter assembly. The memory may further store instructions to enable 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 patient data, clinical data, procedural data, etc. In some embodiments, the signal generator may be configured to generate a waveform in a range between about 250kHz and about 750kHz and between about 120V and about 400V, including all ranges and subvalues ​​therebetween. In some embodiments, the signal generator may be configured to generate an ablation waveform (e.g., a cutting waveform) in a range between about 1W and about 300W, including all ranges and subvalues ​​therebetween. For example, a transvascular opening between the lumen of an MMA and the subdural space may be formed by a signal generator that generates an ablation waveform comprising a power between about 15W and about 60W, a duty cycle of at least about 300ms, and a duration of less than about 5 seconds, including all ranges and subvalues ​​therebetween. For example, an ablation waveform may be generated that lasts less than about 2 seconds.

[0138] Typically, processors described herein (e.g., CPU) can process data and / or other signals to control one or more components of a system. The processor can be configured to receive, process, compile, calculate, store, access, read, write and / or send data and / or other signals. In some embodiments, the processor can be configured to access or receive data and / or other signals from one or more of a sensor (e.g., an impedance sensor, a pressure sensor) and a storage medium (e.g., a memory, a flash drive, a memory card). In some embodiments, the processor can be any suitable processing device configured to run and / or execute a set of instructions or code, and can include one or more data processors, an image processor, a graphics processing unit (GPU), a physical processing unit, a digital signal processor (DSP), an analog signal processor, a mixed signal processor, a machine learning processor, a deep learning processor, a finite state machine (FSM), a compression processor (e.g., for reducing data rate and / or data compression required for memory), an encryption processor (e.g., for secure wireless data and / or power transmission) and / or a central processing unit (CPU). The processor can be, for example, a general-purpose processor, a 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 programs and / or other modules, processes, and / or functions associated with the system. A variety of component types may be provided, including, for example, metal oxide semiconductor field effect transistor (MOSFET) technology such as complementary metal oxide semiconductor (CMOS), bipolar technology such as emitter coupled logic (ECL), polymer technology (e.g., silicon conjugated polymer and metal conjugated polymer-metal structures), mixed analog and digital, and the like.

[0139] The systems, devices, and / or methods described herein may be implemented by software (implemented on hardware), hardware, or a combination thereof. The 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). The software modules (implemented on hardware) may be expressed in a variety of software languages ​​(e.g., computer code), including C, C++, Python, Ruby, Visual and / or other object-oriented, procedural, or other programming languages ​​and development tools. Examples of computer code include, but are not limited to, microcode or microinstructions, machine instructions (such as those generated by a compiler), code for generating network services, and files containing high-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.

[0140] Generally, the ablation devices described herein may include a memory configured to store data and / or information. In some embodiments, the memory may include one or more of a random access memory (RAM), a static RAM (SRAM), a 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), a flash memory, a volatile memory, a non-volatile memory, or a combination thereof. In some embodiments, the memory may store instructions to cause a 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 be associated with a computer storage product having a non-transitory computer-readable medium (also referred to as a non-transitory processor-readable medium) having instructions or computer code thereon for performing various computer-implemented operations. A computer-readable medium (or processor-readable medium) is non-transitory in the sense that it does not itself include a transient propagating signal (e.g., a propagating electromagnetic wave carrying information on a transmission medium such as space or a cable). The media and computer code (also referred to as code or algorithm) may be those designed and constructed for the specific purpose.

[0141] In some embodiments, the system may also include a communication device configured to allow an operator to control the system. The communication device may include a network interface configured to connect the system to another system (e.g., the Internet, a remote server, a database) via a wired or wireless connection. In some embodiments, the system may communicate with other devices (e.g., mobile phones, tablet computers, computers, smart watches, etc.) via one or more wired and / or wireless networks. In some embodiments, the network interface may include one or more of an RF receiver / transmitter, an optical (e.g., infrared) receiver / transmitter, etc., which are configured to communicate with one or more devices and / or networks. The network interface may communicate with one or more of the system, network, database, and server via a wired and / or wireless manner.

[0142] The network interface may include RF circuitry configured to receive and transmit RF signals. The RF circuitry may convert electrical signals into / from electromagnetic signals and communicate with a communication network and other communication devices via the electromagnetic signals. The RF circuitry may include 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 the like.

[0143] Wireless communication by any device may use any of a variety 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 802.11a, IEEE 802.11b, IEEE 802.11b), IEEE 802.11c, IEEE 802.11d ... 802.11g, IEEE802.11n, etc.), Voice over Internet Protocol (VoIP), Wi-MAX, email protocols (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 extended for Instant Messaging and Presence Support (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 can communicate directly with each other without sending data over a network (e.g., without sending data over NFC, Bluetooth, WiFi, RFID, etc.).

[0144] In some embodiments, input devices (e.g., keyboards, buttons, touch screens) and output devices (e.g., display devices) may be configured to receive input data from one or more of a system, a network, a database, and a server. For example, operator control of an input device (e.g., keyboard, buttons, touch screen) may be received by an input / output device, which may then be processed by a processor and memory for the user interface to output control signals to the system. Some embodiments of the input device may include at least one switch configured to generate a control signal. For example, the input device may include a touch surface for an operator to provide input corresponding to a control signal (e.g., finger contact to the touch surface). An input device including a touch surface may be configured to detect contact and movement on the touch surface using any of a variety of touch-sensitive technologies, including capacitive, resistive, infrared, optical imaging, dispersive signals, acoustic pulse recognition, and surface acoustic wave technologies. In embodiments of an input device comprising at least one switch, the switch may include, for example, at least one of a button (e.g., hard key, soft key), a touch surface, a keyboard, an analog stick (e.g., a joystick), a directional pad, a mouse, a trackball, a dial, a stepper switch, a rocker switch, a pointer device (e.g., a stylus), a motion sensor, an image sensor, and a microphone. The motion sensor may receive operator movement data from an optical sensor and classify operator gestures as control signals. The microphone may receive audio data and recognize operator speech as control signals.

[0145] A haptic device can 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, the haptic device can generate a tactile response (e.g., vibration) to confirm an operator input to an input device (e.g., a touch surface). As another example, tactile feedback can notify the operator that the input is overridden by the system.

[0146] Visualization equipment

[0147] In some embodiments, visualization device 570 can be configured to be arranged on one or more parts (for example, conduit 510, shaft 520, hemostasis device 530) of the catheter assembly 502 in the subject's body and be visualized (for example, generate one or more images).As described in more detail herein, visualization device 570 can be convenient for the positioning (for example, distal end portion 522 and perforating element 524 with respect to the orientation and placement of blood vessel) of catheter assembly 502 in the intraluminal and extraluminal blood vessels of the subject.

[0148] In some embodiments described herein, one or more elements of the catheter assembly 502 (e.g., catheter 510, shaft 520, hemostasis device 530) may include a set of fiducials (e.g., radiopaque elements) spaced along the length of the catheter assembly 502 (e.g., catheter 510, shaft 520) and configured to be imaged by a visualization device. For example, the set of fiducials may include radiopaque fluoroscopic markers (FM).

[0149] In some embodiments, the radiopaque element can include one or more of gold, platinum, platinum-iridium, tantalum, bismuth, a tungsten-filled polymer, combinations thereof, etc. In some embodiments, a fiducial can be provided at the proximal end of the perforating element 524 to indicate the relative position of the distal end of the perforating element 524. In some embodiments, the fiducial can be configured to indicate rotational orientation.

[0150] For example, visualization can include one or more of optical coherence tomography (OCT) and intravascular ultrasound (IVUS) tomography. With IVUS, the dura mater, dural appendages, cerebrospinal fluid, superficial pia mater, cortical gray matter, and white matter are hyperechoic. The subarachnoid space contains many blood vessels that are visible in Doppler ultrasound mode. Subdural effusions can have a hyperechoic membrane and can be hyperechoic, hypoechoic, or a combination thereof.

[0151] In some embodiments, visualization can include a combination of invasive (e.g., US, CTO, angioscopy) and non-invasive (fluoroscopy, US, CT, MR) imaging modalities. In some embodiments, catheter 510 can include an optical sensor (e.g., a camera) and / or a light source for endoscopic visualization of one or more of catheter advancement in the subdural or epidural space and transvascular drainage of subdural fluid collections. In some embodiments, the optical sensor can include one or more of an optical fiber, a complementary symmetric metal oxide semiconductor, a scanning fiber endoscope, combinations thereof, and the like.

[0152] In some embodiments, system 500 may include one or more magnets that are configured to provide one or more of directionality, penetration, and navigation. For example, catheter assembly 502 may include a first magnet, and the external source configured to be placed on the outer surface of the head may include a second magnet, wherein the first magnet and the second magnet may be configured to provide one or more of directionality, penetration, and navigation. In some embodiments, magnet may be a permanent magnet, a temporary magnet, and / or an electromagnet. In some embodiments, magnet may be made of one or more of neodymium, samarium cobalt, platinum cobalt, alnico, ceramics, and ferrite.

[0153] Example Implementation

[0154] Figure 6is a schematic diagram of a system 600 including a catheter 610, a shaft 620, a connector 640, and a signal generator 650. The catheter 610 and the shaft 620 may include structures and / or functions similar to those described above with reference to Figure 5 Components of the catheter 510 and shaft 520 are depicted. The system 600 can be configured to form an opening between a blood vessel and the extravascular lumen of a subject and / or deliver a hemostatic element or RF device to close the opening formed by the shaft 620. In some embodiments, the catheter 610 can be slidably disposed within the lumen of the sheath.

[0155] In some embodiments, the shaft 620 may be coupled to the signal generator 650. The shaft 620 may include a distal end portion 622 having a perforating element 624 that is configured to create (e.g., form) an opening in the wall and dura mater of a subject's blood vessel. In some embodiments, the distal end portion 622 may have a predetermined shape, such as a J-shaped curve, as further described below. Alternatively, in some embodiments, the distal end portion 622 may have different predetermined or preset shapes, such as a U-shaped, C-shaped or other atraumatic shapes. In some embodiments, the shaft 620 (e.g., distal end portion 622) may also include an offset portion (not shown) that is configured to orient the shaft 620 in a predetermined orientation when the shaft 620 is advanced within the lumen and blood vessel of the catheter 610. For example, the offset can be configured to rotate (e.g., self-orient) the distal tip portion 622 about the longitudinal axis of the shaft 620 so that the perforating element is directed toward the dura mater and brain while the proximal portion of the J-shaped distal tip portion faces the skull, thereby ensuring that the opening created by the perforating element 630 is formed within an arc that faces the subdural space rather than the skull. In this configuration, the system 600 can be used as a rotational lever, with the fixed path of blood vessels, bone, and dura mater acting as a fulcrum, friction between the system 600 and the blood vessels acting as a resistance, and the release of elastic potential energy corresponding to the predetermined curve of the system 600 causing rotational motion and self-orientation for access from the vasculature into the subdural space.

[0156] As described in more detail herein, the shaft 620 can generally have a rounded cross-sectional shape (e.g., circular or elliptical), while the offset portion can have a relatively flat, oval cross-sectional shape that is configured to rotate or twist the distal end portion 622 to a desired orientation (e.g., away from the skull and toward the dura mater) when advancing through tortuous vasculature. The J-shaped curve of the distal end portion 622 can be advantageous in facilitating atraumatic advancement of the shaft 620 through the subdural space. The J-shaped curve can be constrained when the shaft is advanced through the vasculature, but can form naturally within the subdural space after the shaft 620 creates an opening through the blood vessel and the dura mater. The distal end of the distal end portion 622 can include a perforating element 630, such as an electrode configured to deliver RF energy. In some embodiments, the perforating element 630 can be angled relative to the distal end portion 622.

[0157] In some embodiments, the connector 640 can be configured to couple the catheter 610 and the shaft 620 to a signal generator 650 and a vacuum source (not shown). In some embodiments, the signal generator 650 can be coupled to the shaft 620. In particular, the signal generator 650 can be configured to generate energy (e.g., RF energy) for delivery using the perforating element 624 of the distal tip portion 622.

[0158] In some embodiments, the catheter 610 and / or shaft 620 may include a set of fiducials comprising a first fiducial 630 and a second fiducial 632 that are configured to be imaged and facilitate positioning of the system 600 within the intravascular and extravascular lumens of a subject.

[0159] Figure 7A and Figure 7C is a schematic diagram of shaft assemblies 700, 704, and Figure 7B 、 Figure 7D and Figure 7E are respectively Figure 7A and Figure 7C Detailed schematic diagrams of shaft assemblies 702, 706, and 708 are depicted in FIG. Shaft assemblies 700-708 may include components that are similar in structure and / or function to shafts 520, 620, respectively.

[0160] Figure 7A and Figure 7BThe shaft assemblies 700, 702 shown may include a handle 710, a perforating element 720, a first datum 732, a second datum 734, and a third datum 736. In some embodiments, the first datum 732 corresponds to the position of the perforating element 720, the second datum 734 facilitates confirmation of the shaft self-orientation, and the third datum 736 corresponds to the position of the maximum outer diameter of the shaft. In some embodiments, the perforating element 720 and the first datum 732 may form an angle of between about 5° and about 15° relative to the second datum 734, including all ranges and subvalues ​​therebetween. In some embodiments, as Figure 7B As shown, the curved portion of the shaft assembly formed by the perforating element 720 and the first datum 732 can have a length extending along the longitudinal axis of the shaft assembly 700 of between about 2.3 cm and about 2.7 cm, including all ranges and subvalues ​​therebetween.

[0161] Figure 7C and Figure 7D The illustrated shaft assemblies 704, 706 further depict a distal end portion 740 of the shaft. The distal end portion 740 can have a perforating element 720 configured to create (e.g., form) an opening in the wall and dura mater of a subject's blood vessel. In some embodiments, the distal end portion 740 can have a predetermined shape, such as a J-shaped curve. The distal end of the distal end portion 740 can include the perforating element 720, such as an electrode configured to deliver RF energy. In some embodiments, such as Figure 7C and Figure 7D As shown, the perforating element 720 can be angled relative to the distal end portion 740. When disposed in a vessel (e.g., MMA), the shape of the distal end portion 740 can be constrained by the vessel so that a J-shape is not formed within the vessel. Once the distal end portion 740 is advanced beyond the opening in the vessel and the dura mater, the unconstrained shape of the distal end portion 740 can be formed. In some embodiments, the set of fiducials 732, 734, 736 can be configured to be imaged (e.g., visualized) to facilitate positioning of the shaft assemblies 700-708 within the intraluminal and extraluminal cavities of a subject's blood vessels.

[0162] In some embodiments, the shaft can have a length of at least about 130 cm (e.g., between about 160 cm and about 180 cm) from the femoral or radial entry point. When a cervical entry point is used, the shaft can be shorter. In some embodiments, the perforating element 720 can be angled toward the shaft to focus the energy delivered by the perforating element 720 to the tissue at the contact point so as to vaporize the tissue and minimize heat generation and tissue shrinkage. Additionally or alternatively, (e.g., when the perforating element 720 does not include a contact point for focused energy delivery) a higher energy level that vaporizes (e.g., ablates) more tissue can be used to create a transvascular channel. In some embodiments, such as Figure 7C and Figure 7D As shown, the perforating element 720 can form an angle of between about 15° and about 35° relative to the distal end of the distal tip portion 740, including all ranges and subvalues ​​therebetween.

[0163] In some embodiments, the height of the curved portion of the distal tip portion can be between about 0.5 cm and about 2.0 cm, including all ranges and subvalues ​​therebetween. In some embodiments, wherein the shaft forms a J-shape, such as in Figure 7C and Figure 7D middle.

[0164] The perforating element 720 can have an angle and length configured to provide a controlled depth perforation of the MMA and dura mater rather than the brain. In some embodiments, the distance between the distal end of the perforating element 730 and the distal end of the shaft (e.g., defined by the curved portion of the distal tip portion 740) can be between about 1 cm and about 1.4 cm, including all ranges and subvalues ​​therebetween.

[0165] In some embodiments, the outer diameter of the shaft can vary in a predetermined manner along the length of the shaft. For example, the shaft can have a first outer diameter 733 and a second outer diameter 735 that is larger than the first outer diameter 735. In some embodiments, the first outer diameter 733 of the shaft can generally be between about 0.020 inches and about 0.027 inches, including all ranges and sub-values ​​therebetween. The second outer diameter 735 of the shaft can generally be between about 0.0255 inches and about 0.0270 inches, including all ranges and sub-values ​​therebetween. As shown in Figure 7E, the outer diameter of the shaft can taper from the first outer diameter 733 to the second outer diameter 735 and taper back to the first outer diameter 733, continuing a length between about 4 mm and about 6 mm, including all ranges and sub-values ​​therebetween. In some embodiments, the first benchmark 732 (e.g., the farthest benchmark) can have the second outer diameter 735, while the rest of the shaft has the first outer diameter 733.

[0166] In some embodiments, the second outer diameter can substantially match the inner diameter of a corresponding catheter (e.g., within 0.002 inches) to reduce and / or limit longitudinal advancement of the shaft relative to the catheter. This can facilitate concurrent advancement of the shaft and catheter through the subdural space, wherein the shaft and catheter are fixed relative to each other.

[0167] Figures 8A to 8C 8 are images of different portions of shafts 800, 802, 804. Shafts 800-804 may include components similar in structure and / or function to shafts 520, 620, 700-708 described herein. Figure 8AThe illustrated shaft 800 may include a distal tip portion 840 and a perforating element 820 attached to a distal end of the distal tip portion. In some embodiments, the perforating element 820 may be angled relative to the distal tip portion 840, as described herein. The perforating element 820 may include an electrode configured to deliver RF energy. Figure 8A As shown, the distal tip portion 840 can generally have a J-shaped curve.

[0168] Figure 8B The illustrated shaft 802 illustrates a portion of the shaft between the distal end of the shaft 800 and the proximal portion of the shaft 804. The shaft 802 can include a first datum 832 and an offset 850 configured to orient at least the distal tip portion 840 of the shaft in a predetermined orientation as the shaft is advanced within a vessel. For example, the offset 850 can have an oval cross-sectional shape that is relatively flat relative to the remainder of the shaft, wherein the offset 850 can be configured to rotate or twist the distal tip portion 840 and the perforating electrode 820 when advanced through angled vasculature. The relatively flat shape of the offset 850 can be configured to bend in one plane but not another.

[0169] In some embodiments, the first datum 832 can be positioned at a predetermined distance from the distal end of the shaft 804, the predetermined distance corresponding to the minimum length required for the shaft 804 to be advanced through the foramen spinosum so that the offset 850 self-orients by rotating about the longitudinal axis of the shaft 804. The position of the first datum 832 can be determined empirically and / or based on the subject's anatomy (e.g., CT scan data of a bony MMA groove). Additionally or alternatively, the shape of the distal tip portion 840 can be modified based on the subject's anatomy. Figure 8C A proximal portion 804 of the shaft is depicted including a second datum 834 of the shaft having a second outer diameter that is greater than the first outer diameter 833 .

[0170] Figure 9 is a schematic diagram of a shaft assembly 900 corresponding to a linear distal RF device. The shaft assembly 900 may include components similar in structure and / or function to the shafts 520, 620, 700-708, 800-804 described herein. The shaft assembly 900 may include a handle 910 and a shaft 920. The shaft 920 may include a perforating element 930 and a reference 940. The perforating element 930 may be configured to cut soft tissue and create (e.g., form) an opening in the wall and dura mater of a subject's blood vessel. The shaft 920 may be positioned in a manner similar to the shaft 520, 620, 700-708, 800-804 described herein. Figure 9 Fiducials 940 are shown in FIG. 9 as having a linear (eg, straight) configuration without a predetermined curve. Fiducials 940 can be configured to be imaged (eg, visualized) to facilitate positioning of shaft assembly 900 within a lumen or extravascular space of a subject.

[0171] In some embodiments, the perforated element 930 may have a diameter less than about 16 mm. 2 , between about 1mm 2 With about 5mm 2 In some embodiments, the energy delivery portion of the perforating element 930 may have an area between about 1.3 mm and about 1.7 mm, including all ranges and subvalues ​​therebetween.

[0172] In some embodiments, the perforating element 930 can be configured to deliver between about 1200 A / m 2 and about 12000A / m 2 Between, about 2000A / m 2 About 10000A / m 2 Between, about 2000A / m 2 About 5000A / m 2 Between, about 5000A / m 2 About 10000A / m 2 Between, about 1200A / m 2 and about 6000A / m 2 Between, about 8000A / m 2 and about 12000A / m 2 In some embodiments, the perforated element 930 can be configured to deliver a power between about 10 watts and about 100 watts, between about 20 watts and about 75 watts, including all ranges and subvalues ​​therebetween.

[0173] In order to navigate in the small and delicate blood vessels of the brain, conventional neurovascular guidewires (e.g., Stryker Synchro2, Aristotle 14) have low terminal bending stiffness. However, the shaft disclosed herein requires enough terminal bending stiffness to pierce blood vessels and dura mater. In some embodiments, perforating element 930 may (e.g., when the distal end of shaft 520 is attached to the distal end of distal end portion 522 about 5mm, about 10mm, and about 20mm) have a terminal bending stiffness between about 0.5gf and about 15gf, including all ranges and sub-values ​​therebetween. In some embodiments, the distal portion of shaft 920 (e.g., up to about 300mm from perforating element 930) may have a column strength of up to about 100gf, between about 10gf and about 50gf, and between about 50gf and about 100gf, including all ranges and sub-values ​​therebetween.

[0174] In some embodiments, one or more portions of the shaft 920 can have a cross-section having a first lateral dimension that is greater than a second lateral dimension. In some embodiments, the shaft 920 can include a wider section having a lateral dimension that is equal to or substantially equal to the inner diameter of the lumen of the corresponding catheter to prevent ovalization of the catheter as the catheter is advanced through the opening and to facilitate bending of the shaft in a first plane and to constrain bending in a second plane perpendicular to the first plane.

[0175] II. Methods

[0176] Also described herein are methods for using the systems and devices described herein to access the extravascular intracranial cavity so that transvascular surgery can be performed without opening the skull. In particular, the systems and devices described herein can be configured to facilitate the removal of fluids (e.g., SDH). Methods using such systems and devices can include, for example: positioning a catheter disposed within an intracranial blood vessel of a subject; advancing an axis through the lumen of the catheter so that a curved section of the axis bends in a direction along the curve of the blood vessel; extending the curved section of the axis outside the catheter so that the curved section bends toward the wall of the blood vessel; activating an RF element to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the subject's blood vessel and into the extravascular intracranial cavity; and advancing the shaft and catheter into the extravascular intracranial cavity. In some embodiments, suction can be applied to the lumen of the catheter to remove fluid from the subdural hematoma. The catheter can be withdrawn toward the opening in the artery, and a hemostatic element or RF device can be delivered to close the opening.

[0177] The viscosity of SDH fluid is generally considered too thick to be drained through catheters with the small diameters required for navigation in MMA. However, rheological analysis of a cohort of cSDH samples empirically demonstrated that the catheters described herein can consistently drain cSDH fluid, as shown in the figure showing the relationship between fluid shear rate and viscosity in chronic and subacute subdural hematomas. Figure 18 Specifically, a set of 43 SDH samples from 35 subjects undergoing burr hole surgical drainage was obtained. -1 , about 1.0s -1 , about 10.0s -1 , about 100.0s -1 and about 1000.0s -1 Viscosity was measured at a variable shear rate of 1.5 Å. A variable shear rate was used because the sample was a non-Newtonian fluid with a viscosity that depended on shear rate. An empirical flow rate was measured for each sample through a 0.027-inch inner diameter catheter, which can be steadily advanced into the intracranial MMA trunk.

[0178] 19A to 19CDepicted is a view of a topographic heat map representing the probability of a hematoma being located on the brain surface based on non-contrast head CT of a cohort of 71 subjects with cSDH. Figure 19A is a top view of the hematoma heatmap 1900. The legend represents probability on a scale from 0 to 1 in increments of 0.1, and is in millimeters for x and y. Figure 19B It is an overlay of the hematoma heat map 1902 and a set of arterial perforation trajectories 1940 and 1950 .

[0179] Through modeling and testing, it was found that the location and orientation of the perforations in the MMA correspond to the trajectories 1940, 1950 of the catheter and shaft advanced through the extravascular lumen. Figure 15A FIG is a top view cross-sectional image of a dissected cadaver head with catheter 1560 and shaft 1562 advanced out of perforation 1544 in MMA 1540. Figure 15A As shown, catheter 1560 and shaft 1562 are linearly advanced from perforation 1544 such that the perforation location can be selected to aim catheter 1560 and shaft 1562 toward an area with a high probability of SDH occurring (e.g., toward the top of the patient's head). Figure 15B is a side view of a 3D rendered computed tomography scan of a subject with a catheter 1560 advanced along a linear trajectory from a perforation 1544 in the MMA.

[0180] Figure 19B A set of catheter and axis trajectories from a perforation in the posterior branch of the MMA 1932 are depicted, including a hematoma trajectory 1940 that facilitates entry into a high probability SDH region (e.g., along the horizontal dashed line) and a non-hematoma trajectory 1950 that leads to a low probability SDH region. Figure 19C Is the hematoma heat map 1904 and with Figure 19A An overlay of a set of arterial perforation locations 1920 (e.g., a perforation map) corresponding to the hematoma trajectory 1940 in FIG. Figure 19D is a plot of the probability that the set of arterial perforation trajectories intersects different SDH regions. For example, the percentage of high-probability SDH regions 1910 within the set of arterial perforation trajectories 1920 is significantly higher than the percentage of medium-probability SDH regions 1912 and lower-probability SHD regions 1914. Therefore, perforating the MMA within the set of arterial perforation locations 1920 creates a high probability that the catheter and shaft will be advanced to the subject's high-probability SDH region. For example, of the 107 cases studied, it was estimated that the device described herein was able to reach the SDH in 105 cases by selecting an appropriate perforation point and advancing up to approximately 5 cm within the subdural space. In most cases (92 / 105), the distal tip of the catheter reached an area with a very high probability (e.g., greater than approximately 80%) of SDH presence.

[0181] Morphometric analysis of MMA subjects undergoing MMAe found that the MMA angle at the foramen spinosum was 100° ± 14°, and the MMA groove along the concave middle cranial fossa followed an angle of 160° ± 5.8°. In at least 84% of subjects, a catheter with a distal outer diameter of 0.93 mm (0.036 inches) was sufficient to navigate the main trunk of the MMA. Given the high incidence of bony tunnels (up to 75%) that would preclude perforation, and because of the medial herniated path along the sphenoid ridge that would direct the emerging axis toward the brain, the anterior division of the MMA was not considered to offer a suitable transarterial approach.

[0182] The method of entering the extravascular cavity may include: navigating the catheter assembly to a predetermined position (e.g., a perforation point); creating a transvascular passage from the intravascular chamber to the extravascular chamber; advancing the catheter assembly to perform the procedure. For example, the catheter assembly may be advanced to penetrate the membrane and septum of a subdural hematoma, and then suction is applied to drain the subdural hematoma. The method of using the systems and devices described herein can reduce blood extravasation while maintaining a patent passage, enable navigation within the intracranial cavity without brain perforation or destruction, allow drainage of subdural fluid, and facilitate closure of arteriotomies (e.g., perforations of the arterial wall and / or dura mater) and arterial occlusion when the catheter system is removed.

[0183] Figure 10 1 is a flow chart of a method 100 for performing a medical procedure (e.g., draining a subdural hematoma, delivering a therapeutic agent, implanting a device) within an extravascular space (e.g., the intracranial space, an extravascular space along a subject's spinal cord). Method 1000 may include, at 1010, navigating a catheter to a perforation site via an intracranial vessel of a subject. For example, a distal end of a catheter disposed within the intracranial vessel of the subject may be positioned proximate to a target location. In particular, a middle meningeal artery transvascular subdural hematoma procedure may include advancing a sheath into the MMA (either before or after embolization of the MMA).

[0184] For example, Figure 17A Depicted is a diagram of an MMA 1740 disposed between the brain 1720, the dura mater 1730, and the skull 1710. As shown in axial cross-sections taken along lines AA, BB, and CC, the MMA 1740 is disposed between the dura mater 1730 and the skull 1712. Specifically, the MMA 1740 extends within a recess 1712 of the skull 1710 and is generally parallel to the brain 1720. However, the diameter of the MMA 1740, as well as the diameter of the recess 1712, decreases distally, such that the longitudinal axis of the MMA 1740, extending distally, intersects the dura mater 1730 and is not parallel to the dura mater.

[0185] In some embodiments, a catheter comprising a proximal segment and a distal segment can be advanced through a sheath. The proximal segment can be, for example, a push wire configured to control movement (e.g., translation) of the catheter through the sheath. The tapered outer diameter of the distal segment can be configured to limit the length to which the distal segment can be advanced distally beyond the distal end of the sheath.

[0186] At 1020, the shaft may be advanced distally beyond the distal end of the catheter or flush with the end of the catheter, and the catheter is pulled back to push the shaft out of the sheath. For example, the shaft may be advanced through the lumen of the catheter such that the curved section of the shaft bends in a direction along the curve of the blood vessel. The curved section may be constrained within the lumen of the catheter within the blood vessel. The curved section of the shaft may extend beyond the distal end of the catheter such that the curved section bends toward the wall of the blood vessel and positions a perforating element (e.g., an RF element) disposed at the distal end of the shaft against the wall of the blood vessel. For example, the perforating element may be advanced distally of the catheter and adjacent to a perforation point in a blood vessel (such as an MMA). Alternatively, Figure 17B Depicted is a catheter assembly (e.g., a linear tip RF device, shaft assembly 900) disposed within an MMA 1740 between the dura mater 1730 and the skull 1710. The catheter assembly can include a catheter 1760 and a shaft 1762 that is advanced distally beyond the distal end of the catheter 1760. The shaft 1762, including the perforated tip 1764, can be flexible but is generally linear when unconstrained. That is, the distal portion of the shaft 1762 can be linear and lacks a predetermined curve.

[0187] At 1030, an opening can be created in the wall and dura mater of an intracranial blood vessel using the perforating element of the shaft. For example, the RF element can be activated to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of a blood vessel (e.g., MMA) of the subject and into an extravascular intracranial cavity (e.g., subdural space). Optionally, a fluid (e.g., contrast agent, saline) can be injected adjacent to the opening to confirm the opening, cool the tissue, and / or increase the lubricity and width of the opening. As in Figure 17C , the perforating element 1764 can be configured to perforate the wall of the MMA and provide access to the epidural space (e.g., between the dura mater 1730 and the MMA 1740). Additionally or alternatively, the perforating element 1764 can be configured to perforate the wall of the MMA and the dura mater to provide access to the subdural space (e.g., below the dura mater 1730). For example, RF energy having a predetermined current density can be delivered to the perforating element 1742 to locally vaporize the MMA 1740, but not sufficient to destroy the skull 1710. The longitudinal axis of the MMA 1740 can be angled relative to the dura mater 1730 such that the opening created in the wall of the MMA can form an angle relative to the dura mater 1730 through which the perforating element 1764 and shaft 1762 can be naturally advanced into one or more of the epidural space and the dura mater. For example, Figure 17C Depicted is a shaft 1762 being advanced through the opening 1742 and into the dura mater 1730 at an oblique angle. Figure 17A As shown in the axial view of FIG, the decreasing diameter of MMA 1740 and the recess 1712 in skull 1710 gradually increase the angle at which the longitudinal axis of shaft 1762 intersects dura mater 1730. In some embodiments, shaft 1762 can be advanced through the epidural space by about 1 cm or more, which can ensure that brain 1720 is not perforated.

[0188] At 1040, the shaft can be advanced into an extravascular cavity (e.g., an extravascular intracranial cavity, an extravascular intradural spinal cavity). For example, the shaft can be advanced into the subdural space. In some embodiments, the distal end of the shaft can be advanced into the extravascular intracranial cavity until the curved segment transitions to an unconstrained configuration within the extravascular intracranial cavity. Figure 17D The perforating element 1764 and shaft 1762 are depicted being advanced through the dura mater 1730 and the opening 1742 of the MMA 1740 while delivering a predetermined amount of current density from the perforating element 1764. The opening 1742 in the dura mater 1730 is formed at an angle relative to the surface of the dura mater such that the shaft 1762 extends obliquely through the dura mater 1730 and naturally advances substantially parallel to the surface of the dura mater 1730. In this manner, brain perforation can be prevented during advancement of the shaft and catheter into the extravascular subdural space. In some embodiments, the catheter can be advanced over the shaft and into the extravascular intracranial space. For example, Figure 17E Catheter 1760 is depicted being advanced over shaft 1764 and into the subdural space.

[0189] At 1050, one or more of the catheter and the shaft may optionally be advanced to the target site. For example, the catheter and / or the shaft may be advanced to a subdural hematoma. In some embodiments, the proximal portion of the catheter may be actuated (e.g., pushed) to advance the distal portion of the catheter over the perforating element and into the extravascular cavity (e.g., the subdural space). In some embodiments, the perforating element may be retracted through the catheter and sheath. The sealing area of ​​the catheter may remain disposed within the lumen of the sheath for sealing the catheter to the sheath.

[0190] At 1060, a medical procedure can be performed. For example, suction can be applied to drain a subdural hematoma, deliver a therapeutic agent, implant a sensor or electrode, deliver a biopsy needle, etc. In some embodiments, the distal end of the shaft can be advanced into the subdural hematoma. The catheter can be advanced over at least a portion of the shaft and into the subdural hematoma. After the catheter is positioned within the subdural hematoma, suction can be applied to the lumen of the catheter to remove fluid from the subdural hematoma.

[0191] In some embodiments, a vacuum source can be coupled to the sheath and apply negative pressure to the lumen of the sheath, which propagates from the sheath lumen to the lumen of the distal segment of the catheter to facilitate high-flow SDH drainage. The sheath placed in the MMA blocks antegrade blood flow, and embolization of the distal artery blocks retrograde flow, thereby minimizing the risk of blood extravasation. Optionally, a flat-panel CT scan can be performed to assess, for example, the remaining subdural volume or midline shift.

[0192] At 1070, the catheter can be withdrawn toward the opening in the wall of the intracranial vessel. For example, the catheter can be withdrawn toward an opening created in the wall of an artery (eg, MMA) using the proximal portion of the catheter.

[0193] Optionally, a hemostatic element can be used to close the opening in the wall of the intracranial blood vessel at 1080. For example, a hemostatic element or an RF device can be delivered through the lumen of a catheter to close the opening.

[0194] Optionally, at 1090, an embolic material may be injected to occlude the bleeding branch vessel. In some embodiments, the embolic material may be injected before creating an opening in the wall of the intracranial vessel and the dura mater of the brain (e.g., before step 1030). Steps 1080 and 1090 may be optional when the hole in the intracranial vessel (e.g., a vein) is very small and / or when a device (e.g., an implant) is placed at both ends of the opening.

[0195] about Figures 11A to 11L 、 FIG. 12A to FIG. 12B 、 Figures 13A to 13J 、 14A to 14F 、 FIG. 15A to FIG. 15B 、 Figure 16 and 17A to 17D The steps in method 1000 are described and depicted in more detail. The catheter assembly described in these figures may include a catheter assembly similar in structure and / or function to that described with respect to FIG. Figure 5 、 Figure 6 、 7A to 7D 、 Figures 8A to 8C and Figure 9 Components of the described catheter assembly components.

[0196] Figures 11A to 11L are X-ray images and photographs corresponding to the steps of method 1000 of a method for accessing an extravascular intracranial cavity using MMA 1120. Figures 11A to 11L The anatomical structures depicted in FIG include the MMA 1120 (e.g., middle cranial fossa), the foramen spinosum 1122, the frontal branch of the MMA 1124, the parietal branch of the MMA 1126, the bone 1150 (e.g., skull), and the subdural space 1160. Figure 11AAs shown in image 1100, the distal end of the catheter can be positioned near a target location within an intracranial vessel of a subject. In particular, the catheter can be navigated distally of the foramen spinosum (having a sharp bend) via the MMA 1120. The catheter can be imaged via a first catheter reference 1130 positioned at the distal end of the catheter and a second catheter reference 1132 positioned proximal to the first catheter reference 1130. Figure 11A In the embodiment, the second catheter reference 1132 is positioned just proximal to the foramen 1122 .

[0197] The shaft can be disposed within the lumen of the catheter. The shaft can include a perforating element (e.g., an electrode, a perforating tip) 1142, a first discontinuity between the perforating element and a curved section of the shaft (e.g., a distal end portion), a second discontinuity disposed proximal to the curved section, a first axis reference 1144, and a second axis reference 1146. The second discontinuity can be located at or proximal to the first axis reference 1144. The second discontinuity can include an offset (e.g., a partial helix, a twist) configured to orient the curved section to follow the curve of the blood vessel (the curve following the curve of the skull base and the skull vault having an inner concave surface) as the shaft is advanced within the lumen of the catheter.

[0198] exist Figure 11B In the embodiment, the perforating element 1142 is advanced through the sharp bend of the foramen spinosum and into the middle cranial fossa without the first axis reference 1144 being advanced through the foramen spinosum 1122. In some embodiments, the first axis reference 1144 does not self-orient (e.g., rotate) the distal end of the shaft until the first axis reference 1144 is advanced through the foramen spinosum 1122. Figure 11B As shown in image 1102 of FIG. 1 , the perforating element 1142 has a slight bias toward the bone 1150, such that the perforating element 1142 is more toward the bone 1150 than the subdural space 1160. Figure 11B If the electrode is positioned in the cranial cavity, the opening in the MMA 1120 will be formed facing the bone 1150 rather than the subdural space 1160. Therefore, perforating the MMA at this location will not stably form a clinically relevant channel to the intracranial extravascular space.

[0199] Figure 11C Further advancement of the shaft in the 1142 advances the perforating element 1142 closer to the first catheter reference 1130 and advances the first shaft reference 1144 distal to the foramen spinosum 1122. In this configuration, the potential energy stored in the second discontinuity is released to rotate the distal end of the shaft and the electrode 1142, thereby orienting the shaft toward the wall of the MMA facing the subdural space 1160. Figure 11CAs shown in image 1104 of FIG. 1 , the electrode 1142 is biased toward the subdural space 1160 such that the electrode 1142 naturally contacts the wall of the MMA facing the dura mater and the subdural space 1160. In this manner, visualization of the position of the first axis reference 1144 relative to the foramen spinosum 1122 can be used to determine that the axis has been correctly rotated into the desired orientation (e.g., the perforating element is bent toward the wall of the MMA 1120 facing the subdural space 1160).

[0200] like Figure 11D As shown in the image 1106 of FIG, the distal end of perforating element 1142 is advanced through the first catheter reference 1130, wherein the second axis reference 1146 has been advanced through the foramen 1122. Therefore, the shaft is advanced through the distal end of the catheter. Similarly, due to the rotation provided by the second discontinuity, the shaft in image 1106 has been self-oriented to bend toward the wall of MMA 1120 and subdural space 1160 (e.g., dura mater). In addition to the longitudinal advancement of the shaft, the operator does not need to rotate the shaft to correctly orient perforating element 1142 to form a transvascular channel because the rotation is caused by the tendency of the discontinuity (e.g., the superelastic material in the core of the offset portion, the shaft) to adapt (e.g., follow) to the geometry closest to its resting state. In some embodiments, the second axis reference 1146 located just distal to the foramen 1122 can indicate to the operator that perforating element 1142 is disposed at a predetermined perforation position. Figure 11E is the brain tissue in which the catheter assembly is placed Figure 11D The image 1106 corresponds to the image 1107. The catheter and shaft electrodes 1142 are disposed within the top branch 1126 of the MMA 1120.

[0201] Figure 11F 1 is an image 1108 showing the position of the perforating element 1142 during RF tissue ablation, wherein the perforating element 1142 has created an opening through the MMA 1120 and into the subdural space 1160. The operator does not need to apply force (e.g., push) to the shaft to create the opening. Instead, the RF energy applied to the tissue by the perforating element 1142 and the predetermined bias of the distal end portion (e.g., the curved section) naturally push the end of the perforating element 1142 into the subdural space 1160. When energy is applied and the opening is formed, a slit can be created when the perforating element 1142 is biased into its unconstrained curved shape.

[0202] Figure 11G The middle cranial fossa (right side) Figure 11F FIG109 shows an image 1108 corresponding to an image 1109 in which a perforating element 1142 has formed an opening through the MMA 1120 and the dura mater. The distal end of the perforating element 1142 is at Figure 11GThe curved section of the shaft is further configured to reduce damage to brain tissue as the curved section naturally bends back toward the dura and away from the brain.

[0203] Figure 11H 1 is an image 1110 showing a perforating element 1142 disposed within the subdural space upon completion of tissue ablation. In some embodiments, the distal end portion of the shaft can form a J-shape (e.g., a knuckle shape) when unconstrained. Due to the curved shape of the shaft and the curvature of the MMA along the concave surface of the external middle cranial fossa, the slit can only appear toward the subdural space (self-orienting). The configuration (e.g., length) of the perforating element 1142 can provide a depth-controlled perforation such that the slit is no deeper than the dura mater (e.g., does not contact brain tissue). Thus, the curved section of the shaft can ensure that the perforating element 1142 does not contact and does not damage brain tissue.

[0204] Figure 11I The middle cranial fossa (right side) Figure 11H 111 corresponds to image 1110, wherein the distal tip portion (eg, curved section) 1140 and perforating element 1142 are advanced out of opening 1127 and into the subdural space. Figure 11I As shown, a first discontinuity (e.g., a bend) between the perforating element 1142 and the distal end portion 1140 can provide an inward inclination of the perforating element 1142 to improve point contact between the perforating element 1140 and the vessel wall, thereby concentrating RF energy to vaporize the tissue with minimal heat generation and tissue shrinkage. In some embodiments, the length of the opening is equal to or substantially equal to the length of the perforating element 1142.

[0205] Figure 11J 11 is an image 1112 showing a shaft being advanced along a predetermined trajectory (e.g., a linear trajectory within the 2D plane of the image 1112) from the opening between the MMA 1120 and the subdural space 1160. The first shaft reference 1144 can be advanced to align with the first catheter reference 1130. In some embodiments, the outer diameter of the first shaft reference 1144 can be substantially equal to the inner diameter of the catheter at the first catheter reference 1130 to prevent ovalization of the catheter as described herein. Thus, the catheter and shaft can be advanced together out of the slit opening 1127 without the edge of the catheter becoming lodged against tissue.

[0206] Figure 11K 1 is an image 1114 showing a first catheter fiducial 1130, distal tip portion 1140, and perforating element 1142 advanced from opening 1127 into the subdural space. Distal tip portion 1140 is completely unconstrained and forms an atraumatic shape (e.g., J-shaped, knuckle) that prevents tissue damage as the shaft is advanced through an extravascular lumen.

[0207] Figure 11L The middle cranial fossa (right side) is shown with the catheter and shaft advanced out of the opening 1127 and into the subdural space. Figure 11K Image 1114 corresponds to image 1115 . The catheter and shaft follow a linear trajectory from opening 1127 .

[0208] Figures 13A to 13J is a schematic cross-sectional view of a subject's head corresponding to the steps and apparatus of method 1000 described herein. Figure 13A 、 Figure 13B 、 Figure 13D 、 Figure 13E 、 Figure 13G and Figure 13I is a coronal cross-sectional view of the subject's head. Figure 13C is a schematic axial cross-sectional view of a subject's head. Figure 13F 、 Figure 13H and Figure 13J is a side view of the subject's head.

[0209] Figure 13A is a coronal cross-sectional view 1300 of the head including bone (eg, skull) 1310 , brain 1320 , dura mater 1330 , internal maxillary artery 1340 , middle meningeal artery (MMA) 1342 , and intradural space 1350 . Figure 13B yes Figure 13A Detailed cross-sectional view 1301 of the MMA 1342. The MMA 1342 may include the foramen spinosum 1343 and the middle cranial fossa 1345. Figure 13A As shown, a delivery catheter (e.g., sheath) 1360 can be positioned within the maxillary artery and within the proximal portion of the MMA. A catheter 1362 (e.g., a suction catheter, an occlusion catheter) can be slidably positioned within the lumen of the delivery catheter 1360. The catheter 1362 can be advanced from the distal end of the delivery catheter 1360 and through the foramen spinosum 1343 and into the middle cranial fossa 1345. Figure 13B As shown, shaft 1364 can be slidably disposed within the lumen of catheter 1362. Shaft 1364 can be advanced from the distal end of catheter 1362. Shaft 1364 can include a perforating element 1366 and a curved section configured to self-orient after being advanced through foramen spinosum 1343 such that perforating element 1366 is biased toward the wall of MMA 1342 facing dura mater 1330 and subdural space 1350.

[0210] Figure 13C 13 is a schematic axial view 1302 of a head including bone 1310, brain 1320, dura mater 1330, and MMA 1342. To form a transvascular passage from a blood vessel to an extravascular lumen, an opening must be formed through the dura mater 1330 between the brain and the MMA 1342. For example, the perforating element 1366 may be guided along an arc (e.g., less than 180°), such as Figure 13C However, an opening formed in the MMA 1342 facing the bone 1310 will not provide access to the subdural space, let alone access to the hematoma. Therefore, the correct positioning and orientation of the perforating element 1366 ensures successful access to the extravascular space.

[0211] Energy may be applied to the perforating element 1366 only to form an opening, thereby preventing ablation of brain tissue 1320. The perforating element 1366 may have an atraumatic shape (e.g., a blunt, rounded distal end) so that contact between the perforating element 1366 and the brain will not damage brain tissue.

[0212] Figure 12A and Figure 12B is a schematic representation of tissue impedance. For example, the impedance differences between the brain, subdural space, dura mater, contrast medium, blood vessels, and bone allow impedance measurements to be used to determine the position of a device (e.g., shaft, catheter) within a subject. For example, an impedance measurement of approximately 700 Ω may correspond to the perforating element 1366 self-orienting against the wall of a blood vessel, while an impedance measurement of approximately 450 Ω may indicate that the shaft has not self-orientated and has poor point contact against the blood vessel wall. Figure 12B As shown, the opening created through the wall of the artery and the subdural space may correspond to an increase in impedance from about 700Ω to between about 900Ω and about 1400Ω. When the impedance corresponding to the subdural space is measured, energy delivery may be reduced and / or stopped. In some embodiments, the signal generator may be configured to stop energy delivery when the impedance measurement falls outside this range. For example, the opening created through the wall of the artery and into the bone may correspond to an increase in impedance from about 700Ω to about 2000Ω. Energy delivery may be stopped when an impedance of about 2000Ω is measured, and a notification (e.g., an audible warning, a visual indicator) may be output to the operator by an input / output device. In some embodiments, impedance may be measured throughout the procedure. For example, after aspirating the SDH, the catheter and shaft may be retracted into the blood vessel, which may be confirmed by one or more of fluoroscopy and impedance measurement (e.g., about 400Ω). In some embodiments, the impedance and / or other dielectric properties of tissue may be measured and used to control the delivery of RF energy before, during, and after one or more of creating a transvascular channel, extravascular navigation, and arterial occlusion.

[0213] Figure 13D 1303 is a coronal cross-sectional view of the head in which the perforating element 1366 has formed an opening (e.g., a slit) through the wall of the MMA 1342 and the dura mater 1330 in a non-pushing manner such that the perforating element 1366 and the distal end portion of the shaft 1364 are disposed within the subdural space 1350. Figure 13Eis a coronal cross-sectional view 1304 of the head, wherein the shaft 1364 is further advanced out of the opening 1346 into the subdural space 1350, such that the distal end portion of the shaft 1364 transitions from a radially constrained configuration (e.g., following the shape of the MMA 1342) to a curved configuration (e.g., forming a J-shape or articulated shape). Figure 13F 1305 is a side view of the head, with axis 1364 extending from MMA 1342 into the subdural space. The trajectory of axis 1364 from the opening in the artery intersects SDH 1370. For SDH 1370 with a large volume, axis 1364 can enter SDH 1370 directly after emerging from the arterial lumen and dura mater. During advancement in the subdural space, the curved configuration of axis 1364 can be parallel to the surface of the brain (as opposed to toward the brain). In some embodiments, saline flushing can be infused into the subdural space to facilitate advancement of the catheter assembly (e.g., to increase surface lubricity and expand the volume of the subdural space) and direct visualization using an optical sensor (e.g., a camera). Figure 13F Further illustrated adjacent to the SDH 1370 is an embolic material 1380 (eg, 150 μm to 250 μm PVA particles) previously delivered to an arterial vessel.

[0214] Figure 13G is a coronal cross-sectional view 1306 and Figure 13H 1307 is a side view of the head with shaft 1364 and catheter 1362 advanced into the subdural space toward the SDH. Specifically, shaft 1364 has been atraumatically advanced through the subdural space into the SDH 1370 and has passed through the cystic wall of the SDH 1370.

[0215] Figure 13I is a coronal cross-sectional view 1308 of the head and Figure 13H is a side view 1309 of the head, wherein the catheter 1362 has been advanced into the SDH 1370 and the shaft 1364 has been retracted through the lumen of the catheter 1362. Figure 13I and Figure 13H Aspiration 1372 (e.g., suction, drainage) of the SDH 1370 is depicted through the lumen of the catheter 1362. In some embodiments, the aspiration can be one or more of continuous, dynamic, cyclic, and pulsatile. Pulsatile pressure can induce clot fatigue and rupture, thereby facilitating aspiration removal.

[0216] about 14A to 14F Other embodiments of SDH drainage and arterial embolization are shown and described. 14A to 14F is a schematic cross-sectional view of a subject's head corresponding to the steps and apparatus of method 1000 described herein. Figure 14A 、 Figure 14C and Figure 14E is a coronal cross-sectional view of the subject's head. Figure 14B 、 Figure 14D and Figure 14F is a side view of the subject's head.

[0217] Figure 14A FIG1 is a coronal cross-sectional view 1400 of the head including bone (e.g., skull) 1410, brain 1420, dura mater 1430, carotid artery 1440, middle meningeal artery (MMA) 1442, and intradural space 1450. MMA 1442 may include foramen spinosum 1443 and middle cranial fossa 1445. Figure 14A As shown, a delivery catheter (e.g., sheath) 1460 can be positioned within the maxillary artery and within the proximal portion of the MMA. A catheter 1462 (e.g., a suction catheter, an occlusion catheter) can be slidably positioned within the lumen of the delivery catheter 1460. The catheter 1462 can be advanced into the subdural space. In some embodiments, Figures 13A to 13J The shaft 1364 depicted in FIG1 can be retracted from the catheter to allow a second shaft 1464 (e.g., a second RF device having a second electrode) including a linear tip configured to penetrate the membrane of the subdural hematoma 1470. The second shaft 1464 can be slidably disposed within the lumen of the catheter 1462. The second shaft 1464 can be advanced from the distal end of the catheter 1462 to contact the outer layer (e.g., cyst wall, membrane) of the SDH 1470. Energy (e.g., RF energy) can be applied by the second shaft 1464 to perforate the membrane of the SDH 1470 and facilitate entry of the second shaft 1464 and the catheter 1462 into the SDH 1470. In some embodiments, the second shaft 1464 can have a linear distal end configured to deliver RF energy to form an opening in the SDH 1470. Figure 14A Also depicted is embolic material 1480 that was previously delivered to a vessel adjacent to the SDH.

[0218] Figure 14B yes Figure 14A 1401 , where the catheter 1462 has been advanced into the SDH 1470 and the second shaft 1464 has been retracted. Figure 14B In the embodiment of the present invention, suction 1472 is applied to remove blood and fluid from the SDH 1470 through the lumen of the catheter 1462. Once the SDH 1470 has been drained (eg, emptied), the catheter 1462 can be retracted from the subdural space and into the MMA 1442.

[0219] In some embodiments, the second shaft can be used to close the opening in the MMA created by the first shaft as the catheter and second shaft are retracted from the subdural space. Figure 14C Coronal cross-sectional views 1402, 1403 of the head and blood vessels are depicted, respectively. Figure 14DSide views 1404 and 1405 of the head and blood vessels are depicted, respectively. Figure 14C and Figure 14D 14, a distal end of each of the catheter 1462 and the second shaft 1464 is disposed within the MMA 1442. The second shaft 1464 can extend outside the catheter 1462 at or proximal to an opening formed in the MMA 1442. In some embodiments, the second shaft 1464 can be configured to deliver RF energy to thermally coagulate (e.g., clot) the MMA to close the opening.

[0220] In some embodiments, the opening created by the shaft in the MMA can be closed by delivering an embolic material using the catheter as the catheter is retracted from the subdural space. Figure 14E Coronal cross-sectional views 1406, 1407 of the head and blood vessels are depicted, respectively. Figure 14F Side views 1408 and 1409 of the head and blood vessels are depicted, respectively. Figure 14E and Figure 14F In the embodiment, catheter 1462 is disposed within MMA 1442 and is used to deliver embolic material (e.g., coils) 1482 into MMA 1442 to close openings formed in the wall of MMA 1442 and / or occlude branch vessels of MMA 1442. The catheter assembly (e.g., catheter 1462, delivery catheter 1460) may then be retracted from the subject.

[0221] In some embodiments, the embolic material can include one or more of a balloon, a gel foam, collagen, thrombin, particles (e.g., polyvinyl alcohol, microspheres), a coil (e.g., pushable, injectable, removable), a liquid agent (e.g., glue, ethylene vinyl alcohol), a sclerosant (e.g., sodium tetradecyl sulfate, ethanol, alginates), a plug (e.g., including a self-expandable cylindrical or hourglass shape), a suture, an electrocoagulant, combinations thereof, etc. In some embodiments, the embolic material can be configured to prevent accidental withdrawal during device withdrawal, such as localized expansion on the distal segment of a gel foam, collagen plug, and a flowering element that radially expands after being pushed out of the sheath, hydrated, exposed to ions, etc. In some embodiments, an embolic material, such as a coil, can be transected at a predetermined length by one or more chemical, mechanical, and electrical mechanisms.

[0222] Also described herein are methods for accessing extravascular intracranial spaces (e.g., the supratentorial parasagittal intradural compartment) using a transvenous approach using the systems and devices described herein. It may be helpful to briefly identify and describe the relevant anatomical structures. The intradural compartment is composed of the subdural space, the subarachnoid space and its enlargements (e.g., the cisterna magna), brain tissue, and the ventricles (e.g., fluid-filled cavities within the brain). The supratentorial compartment is considered the intracranial space above the tentorial bones, and the infratentorial compartment is considered the intracranial space above the tentorial bones. Figure 16 is a perspective cross-sectional view 1600 of a subject's head, including a skull 1610 , brain 1620 , dura mater 1630 , and superior sagittal sinus 1640 .

[0223] In some embodiments, the systems and devices described herein can be navigated from a peripheral venous approach into the dural venous sinuses (e.g., including the superior sagittal sinus and superior petrosal sinus) and create an opening through the venous wall and dura mater to the subdural space for access to the extravascular space. Optionally, the subdural space can be expanded by delivering fluid or gas to facilitate delivery of one or more fluid-based therapeutic agents and devices through the transvascular access point.

[0224] For example, a delivery sheath can be navigated from a peripheral venous access to the jugular vein, sigmoid sinus and transverse sinus and into the superior sagittal sinus. The sheath can be guided toward the side wall of the ipsilateral sinus. The shape of the SSS is generally triangular, with the largest side being the base directed against the skull. The delivery sheath can be arranged at the base (e.g., skull) of the triangle and directed toward the subdural space toward the side wall of the sinus. In some embodiments, the dural sinus wall can be penetrated by an axis. Then, one or more devices can be navigated into the extravascular space, comprising a catheter configured to attract (e.g., from SDH) fluid. After completing the intervention in the extravascular space, the device can be retracted, and the opening can be closed using a hemostatic device as described herein. Therefore, these methods can minimize blood extravasation when the passage is unobstructed, enabling navigation within the intracranial cavity without causing brain perforation or destruction, allowing drainage of subdural effusion (e.g., SDH), and facilitating closure of the dural incision when removing the catheter assembly.

[0225] In some embodiments, one or more devices may be temporarily or permanently placed (e.g., implanted) in the extravascular lumen. For example, the device may include one or more electrodes, sensors, transmitters, receivers, meshes, ports, catheters, biopsy needles or punches, implantable chemotherapy wafers or radiation seeds, combinations thereof, and the like.

[0226] It should be understood that the devices, systems, and methods described herein are not intended solely for use in draining fluid, clots, and particulate matter from the subdural space. Rather, the methods and systems described herein may be adapted to gain safe access and drain fluid and clots from the epidural space, for example, to evacuate acute epidural hematomas, cystic fluid, and pus.

[0227] In addition, the methods and systems described herein can be adapted to obtain access to any intracranial target in the epidural and intradural spaces, including the subarachnoid space, cisterns, brain tissue, and ventricles. It should be understood that the methods and systems described herein can be adapted and used to obtain safe access to the subdural or epidural spaces and to drain fluids, particulate matter, and clots through veins, dural sinuses, and any other natural channels. For example, the devices, systems, and methods described herein can be used to obtain safe and stable transvascular access to any extravascular space and then close the arteriotomy or venous incision site. It should also be understood that the methods and systems described herein can be adapted and used to obtain access to the intradural space in the spine.

[0228] Figure 20A is a three-dimensional image 2000 (eg, a reconstruction) of a set of veins and dural sinuses in a subject's head, including a superior sagittal sinus 2020 and cortical veins 2030 branching therefrom. Figure 21A 21 is a corresponding schematic diagram of a top view of cranial anatomy including the brain 2110, the superior sagittal sinus 2120, and the cortical veins 2130. The SSS 2120 extends along the midline, and the cortical veins 2130 drain into the SSS 2120.

[0229] Figure 20B is a coronal cross-sectional view 2010 of the subject's head. Figure 21B is a corresponding schematic diagram 2110 of a coronal cross-sectional view of the cranial anatomy including the brain 2110 , SSS 2120 , bone 2140 , the subdural space 2150 (eg, between the brain 2110 and SSS 2120 ), and the falx cerebri 2160 .

[0230] Figure 22 22 is a schematic top view and coronal cross-sectional view of a subject's head with a catheter assembly as described herein. For example, the shaft 2230 and catheter 2240 of the catheter assembly are disposed within the superior sagittal sinus 2210. The delivery catheter 2250 can be configured to navigate the catheter assembly into the SSS 2210. The shaft 2230 and catheter 2240 can include components similar in structure and / or function to those described with respect to FIG. Figures 5 to 9 Components of the shaft and catheter described herein. In some embodiments, the catheter 2240 can include a dilator having a tapered distal end with a distal opening. Similarly, the distal end of the shaft (e.g., the shaft tip) can have a smaller diameter than the rest of the shaft 2230, enabling the distal end to create a small opening in the sinus wall and dura mater. Further advancement of the shaft 2230 (and its relatively large diameter) through the sinus wall and dura mater can temporarily dilate the tissue and facilitate advancement of a larger catheter.

[0231] In some embodiments, the distal portion of the shaft 2230 can be formed of a shape memory material (e.g., nitinol) having a predetermined curve, such that the distal portion of the shaft 2230 bends when the shaft is advanced from the distal end of the catheter 2240. The shape of the predetermined curve can include, but is not limited to, a simple curve, a compound curve, an inverted curve, a spiral curve, a complex curve, combinations thereof, and the like. The predetermined curve can be in one or more planes (e.g., a horizontal plane, a vertical plane). In some embodiments, the unconstrained curve of the shaft 2230 can be configured to contact the wall of the SSS 2210 opposite the perforation point, such that the tip of the shaft contacts the wall of the SSS at the perforation point.

[0232] As shown in the cross-sectional view of 2200, when the length of a portion of the shaft 2230 (e.g., the long chord of the curve of the shaft 2230) is equal to or greater than the length of the base of the triangular SSS 2210, the shaft 2230 can naturally conform (e.g., adapt) to the wider dimension of the SSS 2210. Typically, the SSS 2210 is longer in the medial-lateral direction than in the cranio-caudal direction, such that the SSS 2210 approximately has the shape of an obtuse isosceles triangle, but the SSS 2210 can be locally larger in the cranio-caudal direction, where the SSS 2210 approximates an acute isosceles triangle with its base at the bone. For example, the extended shaft 2230 can generally conform (e.g., conform to, spatially orient, follow) the medial-lateral projection of the SSS 2210, thereby providing a stable wall fit that minimizes herniation and recoil when receiving antegrade longitudinal mechanical loads, thereby providing a perforation point at the base corner (e.g., lateral vertex) of the generally triangular sinus.

[0233] In some embodiments, the shaft 2230 can be positioned along a trajectory that is substantially parallel to the dura mater and the brain surface to enter the subdural space. For example, a transvascular access trajectory that is parallel to the base of the triangular SSS 2210 can facilitate implantation of a closure device away from the center of the venous lumen, which can facilitate patency. In some embodiments, one or more of the shaft 2230, catheter 2240, and delivery catheter 2250 can have a predetermined curve to facilitate self-orientation to the SSS 2210. In some embodiments, access to the puncture site can be achieved using one or more predetermined curves and by twisting one or more of the shaft 2230, catheter 2240, and delivery catheter 2250.

[0234] At 2202, energy (e.g., RF energy) can be delivered to the wall of the SSS 2210 and the dura mater to create an opening (e.g., a hole, a slit) 2212, through which the shaft 2230 is advanced. At 2204, the shaft 2230 is further advanced through the subdural space and the catheter 2240 is advanced through the opening 2212. For example, the unconstrained shape of the shaft 2230 can form a J-shape. Although not shown, a delivery catheter 2250 can be advanced over the catheter 2240 through the opening 2212. Thereafter, the medical procedure can be performed as described herein.

[0235] In some embodiments, the distal portion of the shaft 2230 may have a compound curve. For example, the shaft 2230 may have a first radius of curvature and a second radius of curvature that is approximately the same as the first radius of curvature. The first radius of curvature may be smaller than the second radius of curvature to facilitate self-orientation of the shaft within the SSS2210 to guide the distal end of the shaft 2210 to and contact the apex of the sinus. The shaft having the second radius of curvature further reduces the risk of herniation of the shaft within the sinus during advancement of the shaft through the opening 2212. One or more of a compound curve, a shape memory material, a tapered shape, and a variable stiffness may be used to mitigate the tendency of the shaft 2210 to herniate (e.g., bend) toward the SSS2210 after partially emerging into the extravascular lumen.

[0236] In some embodiments, the system 600 can be configured to perforate a blood vessel wall and enter the epidural space using a predetermined curve of the shaft having a first curve in a first plane (e.g., a horizontal plane) and a second curve in a second plane (e.g., a vertical plane). Thereafter, a medical procedure can be performed in the epidural space. Alternatively, a medical procedure can be performed after entering the subdural space via a dural incision.

[0237] Figure 23 2300, 2302, 2304, 2306, and a cross-sectional view 2308 of a catheter 2310. In some embodiments, the catheter 2310 can include a wire 2312, a perforating element 2320 (e.g., a nitinol needle), and a pusher 2330 configured to translate the perforating element 2320. The distal portion of the catheter can include a stopper 2316 having a bevel 2318 (e.g., a taper, a bend, a chamfer, an angle) configured to guide the perforating element 2320 out of an opening (e.g., a window) 2314 of the catheter 2310. The perforating element 2320 can be configured to translate within the catheter 2310 and be advanced out of the catheter using the pusher 2330 slidably disposed within the catheter 2310. The perforating element 2320 can include a cutting edge (e.g., a blade, a bevel, a cutter). For example, once the perforating element 2320 contacts the inclined surface 2318 of the stop 2316, the perforating element 2320 can be bent out of the opening 2314 in a predetermined manner. Figure 23 In the embodiment of the present invention, the curvature of the perforating element 2320 increases as the perforating element is advanced out of the catheter 2310. In some embodiments, the predetermined curvature of the perforating element 2320 can determine the trajectory of the perforating element 2320 within the subdural space. This can facilitate, for example, the delivery of a cortical implant to a predetermined portion of the brain.

[0238] In some embodiments, the catheter 2310 can include an annular fluorescent marker configured to aid in visualization and guide positioning of the catheter within the subject. For example, the annular fluorescent marker 2340 can have a C-shape as shown in the cross-sectional view 2308. In particular, the fluorescent marker 2340 can be disposed around the opening 2314 of the catheter 2310. In some embodiments, the stopper 2316 can include an ultrasound device (e.g., intravascular ultrasound).

[0239] Figure 24 Is such as about Figure 23 Schematic top view and coronal cross-sectional view of the subject's head of the catheter assembly shown and described. The catheter 2310 can be disposed within the subject's superior sagittal sinus 2410. At 2400, the catheter 2310 can be guided via imaging (e.g., X-ray) within the SSS 2410 so that the opening 2420 formed by the catheter 2310 is not formed in the cortical vein. The opening 2314 of the catheter 2310 can be oriented toward the opening 2420 to form in the SSS 2410. An annular fluorescent marker can be visualized within the SSS 2410 and used to determine the orientation of the opening 2314 within the SSS 2410.

[0240] At 2402, the perforating element 2320 can be advanced out of the catheter 2310 toward the wall of the SSS 2410 to form an opening 2420 in the SSS 2410. Due to the strength of the dura mater, as the perforating element 2320 contacts and advances through the wall of the SSS 2410 and the dura mater, a reaction force is generated where the catheter 2310 is pushed against the opposing sidewall of the SSS 2410. In some embodiments, the length of the curved distal end portion of the perforating element 2320 can be between about 15 mm and about 25 mm, including all ranges and subvalues ​​therebetween. At 2404, the shaft 2430 can be advanced from the lumen of the perforating element 2320 and into the subdural space to perform a medical procedure as described herein (e.g., draining an SDH, delivering an electrode).

[0241] Figure 252502 is a schematic coronal cross-sectional view of a subject's head. In some embodiments, the delivery catheter 2520 can be articulated (e.g., using at least one pull wire) to bend the distal end of the catheter assembly. The predetermined curve of the catheter assembly can orient the distal opening of the delivery catheter 2520 toward and contact a predetermined wall (e.g., at or near a bottom corner or side vertex) of the SSS2570, and (e.g., by actuating the pull wire) provide sufficient hardness to provide a reaction force against the resistance of the SSS2570 and the dura mater when producing a transvascular opening. That is, at 2502, the delivery catheter 2520 can be configured to anchor against the wall of the SSS2570. In some embodiments, the catheter 2530 can be configured to increase its stiffness (e.g., via the actuation of the pull wire) when actively manipulated, and reduce its stiffness (e.g., via the release of the tension on the pull wire) when not actuated. Higher stiffness of the shaft may facilitate device delivery (eg, shaft advancement) during transvascular access creation corresponding to a support mode, while lower stiffness may facilitate coaxial advancement over the wire corresponding to a tracking mode.

[0242] At 2504, the perforating element 2540 can be advanced through the wall of the SSS 2570 and the dura mater to form an opening. At 2506, a guidewire 2550 can be advanced through the lumen of the perforating element 2540 into the subdural space. At 2508, a catheter 2530, such as a dilator, can be advanced over the perforating element 2540 into the subdural space. One or more of the catheter 2530, the perforating element 2540, and the guidewire 2550 can be advanced into the subdural space for a medical procedure involving drainage of a subdural hematoma 2590. In this case, at 2510, the perforating element 2540 and the guidewire 2550 are retracted to facilitate aspiration of the SDH 2590 through the lumen of the catheter 2530. At 2512, a device (e.g., a coil) can be delivered into the subdural space using the catheter 2530. At 2514, catheter 2530 may be used to deliver staples 2560. At 2516, staples 2560 may be used to close the opening formed in SSS 2570. However, if an implantable device (e.g., a catheter, a sensor, one or more wires, an electrode) remains through the transvascular passage, staples (or other closure device) may not be used.

[0243] In some embodiments, at least a portion of the catheter assembly positioned in the subdural space can be articulated to facilitate navigation through blood vessels and the subdural space. For example, dural sinuses often contain multiple draining veins that may be susceptible to accidental injury. In some variations, the draining veins (e.g., emissary veins) can be imaged (e.g., via angiography) to facilitate perforation of the sinus wall without perforating the veins. In some variations, the catheter can be configured to articulate, and a shaft having a perforating element can be advanced through the lumen of the catheter and used to create a transdural opening leading to the subdural space. A predetermined length of shaft can be advanced into the subdural space, the catheter can be relaxed (e.g., by releasing tension on a pull wire), and then advanced over the shaft into the subdural space. The catheter in the subdural space can then be actuated (e.g., steered) to navigate toward an area of ​​interest (e.g., a subdural hematoma). The shaft (or other wire) of the catheter assembly can be advanced toward the area of ​​interest. If the stiffness of the shaft is less than the stiffness of the curve, the shaft will follow the trajectory of the catheter and advance toward the area of ​​interest. The catheter can then be relaxed and subsequently advanced over the shaft to the region of interest, and medical procedures can be performed, including but not limited to drainage of a multilocular subdural hematoma, delivery of diagnostic and / or therapeutic agents and / or devices to one or more extravascular intracranial targets.

[0244] Figure 26 The dielectric constant of a group of tissue types, including blood, gray matter, white matter, arterial wall, cancellous bone, dura mater, cortical bone, and cerebrospinal fluid, is plotted against frequency. For RF frequencies below 520 kHz, the magnitude of the dielectric constant does not change. At higher frequencies, the order of dielectric constant decreases as blood, gray matter, white matter, arterial wall or cancellous bone or dura mater, cortical bone, and cerebrospinal fluid. Figure 27 is a plot of the dielectric constant for a set of tissue types for a set of RF frequencies.

[0245] Although various inventive embodiments have been described and illustrated herein, a person of ordinary skill in the art will readily envision various other ways and / or structures for performing the functions and / or obtaining the results and / or one or more advantages described herein, and each of these variations and / or modifications is considered to be within the scope of the inventive embodiments described herein. More generally, a person skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications and anatomical structures (e.g., intracranial and extracranial vascular structures) for which the present invention is to be used. A person skilled in the art will recognize or be able to determine many equivalents to the specific inventive embodiments described herein using at most routine experimentation. Therefore, it should be understood that the foregoing embodiments are presented as examples only and are within the scope of the appended claims and their equivalents; embodiments of the present invention may be implemented in a manner other than as specifically described and claimed. The inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods, if such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

[0246] Furthermore, various inventive concepts may be embodied as one or more methods, examples of which have been provided. The actions performed as part of the method may be ordered in any suitable manner. Thus, embodiments may be constructed in which actions are performed in an order different from that illustrated, which may include performing some actions simultaneously, even though illustrated as sequential actions in the illustrative embodiments.

[0247] As used herein, when used in conjunction with numerical values ​​and / or ranges, the terms "about" and / or "approximately" generally refer to those numerical values ​​and / or ranges that are close to the recited numerical values ​​and / or ranges. In some cases, the terms "about" and "approximately" can mean within ±10% of the recited value. For example, in some cases, "about 100 [units]" can mean within ±10% of 100 (e.g., 90 to 110). The terms "about" and "approximately" can be used interchangeably.

[0248] Any and all references to publications or other documents, including but not limited to patents, patent applications, articles, web pages, books, etc., presented anywhere in this application are hereby incorporated by reference in their entirety. Furthermore, all definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0249] The specific examples and descriptions herein are exemplary in nature, and implementations may be developed by those skilled in the art based on the teachings herein without departing from the scope of the present invention.

Claims

1. A device for draining a subdural hematoma disposed in an extracranial cavity of a patient's intracranial blood vessel, the device comprising: a suction catheter, the suction catheter being capable of being disposed within an intracranial blood vessel of the patient, the suction catheter defining a lumen; as well as a shaft configured to be advanced through the lumen of the catheter until a distal tip portion of the shaft is disposed within the intracranial vessel, the shaft comprising: a perforating element configured to cut through the wall and dura mater of the intracranial blood vessel of the patient to create a slit, the slit serving as a passage from the lumen of the intracranial blood vessel to the extraluminal space of the intracranial blood vessel; a distal segment coupled to the distal tip portion, the distal segment having a cross-section having a first lateral dimension greater than a second lateral dimension to facilitate bending of the shaft in a first plane and to constrain bending in a second plane perpendicular to the first plane; and The suction catheter is configured to be advanced through the slit and to the subdural hematoma to allow fluid or material from the subdural hematoma to be drained out of the intracranial extravascular space via the lumen of the catheter.

2. The device of claim 1 , wherein the perforating element is configured to deliver between about 1200 A / m 2 and about 12000A / m 2 The current density between .

3. The device of claim 1, wherein the perforated element is configured to deliver between about 10 W and about 100 W of power.

4. The device of claim 1, wherein the perforating element comprises a tip bending stiffness of up to about 15 gf.

5. The device of claim 1, wherein the shaft has a column strength of up to about 100 gf.

6. The device of claim 1 , wherein the shaft further comprises a wider section having a lateral dimension equal to or substantially equal to an inner diameter of the lumen of the suction catheter to prevent ovalization of the suction catheter when the suction catheter is advanced through the longitudinal slit.

7. The device of claim 1 , wherein the suction catheter includes a proximal end configured to be coupled to a suction source such that the suction source can apply suction to the lumen to drain the fluid or substance from the subdural hematoma.

8. The device of claim 1, wherein the perforating element has an atraumatic shape.

9. The device of claim 1 , wherein the shaft further comprises a proximal segment having an outer diameter tapering from a first outer diameter substantially equal to an inner diameter of the aspiration catheter to a second outer diameter such that the proximal segment is configured to limit the length to which the shaft can be advanced distally beyond the distal end of the aspiration catheter.

10. The device according to claim 1 further includes a sheath defining a sheath lumen configured to receive the suction catheter, wherein the suction catheter includes a distal segment, the distal segment includes a proximal portion, the outer diameter of the proximal portion tapering from a first outer diameter substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion is configured to limit the length to which the distal segment can be advanced distally beyond the distal end of the sheath.

11. A device for draining a subdural hematoma disposed in an extracranial space of a patient's intracranial blood vessels, the device comprising: a suction catheter, the suction catheter being capable of being disposed within an intracranial blood vessel of the patient, the suction catheter defining a lumen; as well as a shaft configured to be advanced through the lumen of the suction catheter until a distal tip portion of the shaft is disposed within the intracranial vessel, the distal tip portion being coaxial with the shaft, the shaft comprising: A perforating element is disposed at the distal end of the distal tip portion, the perforating element being configured to obliquely cut through the wall and dura mater of the patient's intracranial blood vessel to create a passage from the intracranial blood vessel to the extracranial cavity of the intracranial blood vessel, the suction catheter being configured to be advanced through the passage and reach the subdural hematoma to allow fluid or substance from the subdural hematoma to be drained out of the extracranial cavity of the intracranial blood vessel via the lumen of the catheter.

12. The device of claim 11, wherein the perforating element is configured to deliver between about 1200 A / m 2 and about 12000A / m 2 The current density between .

13. The device of claim 11, wherein the perforated element is configured to deliver between about 10 W and about 100 W of power.

14. The device of claim 11, wherein the perforating element comprises a tip bending stiffness of up to about 15 gf.

15. The device of claim 11, wherein the shaft has a column strength of up to about 100 gf.

16. The device of claim 11, wherein the shaft further comprises a wider section having a lateral dimension equal to or substantially equal to an inner diameter of the lumen of the suction catheter to prevent ovalization of the suction catheter when the suction catheter is advanced through the longitudinal slit.

17. The device of claim 11, wherein the suction catheter includes a proximal end configured to be coupled to a suction source such that the suction source can apply suction to the lumen to drain the fluid or material from the subdural hematoma.

18. The device of claim 11, wherein the perforating element has an atraumatic shape.

19. The device of claim 11 , wherein the shaft further comprises a proximal segment having an outer diameter tapering from a first outer diameter substantially equal to an inner diameter of the aspiration catheter to a second outer diameter such that the proximal segment is configured to limit the length to which the shaft can be advanced distally beyond the distal end of the aspiration catheter.

20. The device according to claim 11 further includes a sheath defining a sheath lumen configured to receive the suction catheter, wherein the suction catheter includes a distal segment, the distal segment includes a proximal portion, the outer diameter of the proximal portion tapering from a first outer diameter substantially equal to the inner diameter of the sheath to a second outer diameter, such that the proximal portion is configured to limit the length to which the distal segment can be advanced distally beyond the distal end of the sheath.

21. A method comprising: positioning a distal end of a catheter disposed within an intracranial blood vessel of a subject proximate to a target location; advancing a shaft through the lumen of the catheter; extending a distal tip portion of the shaft beyond and coaxially with the distal end of the catheter to position a radiofrequency (RF) element of the distal tip portion against a wall of the blood vessel and at an oblique angle relative to an overlying surface of the dura mater; activating the radio frequency (RF) element to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the blood vessel and into an extravascular intracranial cavity of the subject; advancing the distal end of the shaft substantially parallel to the surface of the dura mater into the extravascular intracranial cavity; as well as The catheter is advanced over the shaft and into the extravascular intracranial cavity.

22. The method according to claim 21, further comprising: advancing the distal end of the shaft into a subdural hematoma; as well as advancing the catheter over at least a portion of the shaft and into the subdural hematoma; as well as After the catheter is positioned within the subdural hematoma, suction is applied to the lumen of the catheter to remove fluid from the subdural hematoma.

23. The method according to claim 21, further comprising: withdrawing the catheter toward the opening created in the wall of the artery; as well as A hemostatic element or RF device is delivered through the lumen of the catheter to close the opening.

24. A device for draining a subdural hematoma disposed in an extracranial space of a patient's intracranial blood vessels, the device comprising: a suction catheter, the suction catheter being capable of being disposed within an intracranial blood vessel of the patient, the suction catheter defining a lumen; as well as a shaft configured to be advanced through the lumen of the catheter until a distal tip portion of the shaft is disposed within the intracranial vessel, the shaft comprising: a perforating element configured to cut through the wall and dura mater of the intracranial blood vessel of the patient to create a slit, the slit serving as a passage from the lumen of the intracranial blood vessel to the extraluminal space of the intracranial blood vessel; as well as a predetermined curved section configured to be constrained into a substantially straight configuration when disposed within the lumen of the catheter and to curve toward the wall of the intracranial blood vessel when exiting the lumen of the catheter, The predetermined curved section is further configured to transition to a curved configuration in response to the perforating element piercing the wall of the intracranial blood vessel and the dura mater, and to cause the perforating element to follow an arc forming the slit in the wall of the intracranial blood vessel and the dura mater, The suction catheter is configured to be advanced through the slit and to the subdural hematoma to allow fluid or material from the subdural hematoma to be drained out of the intracranial extravascular space via the lumen of the catheter.

25. The device of claim 24, wherein the suction catheter includes a proximal end configured to be coupled to a suction source such that the suction source can apply suction to the lumen to drain the fluid or material from the subdural hematoma.

26. The device of claim 24, wherein the predetermined curved section has a J-shape or a U-shape in the curved configuration.

27. The device of claim 24, wherein the perforating element has an atraumatic shape.

28. The device of claim 24, wherein the perforating element is configured to generate radio frequency (RF) energy to cut through the wall of the intracranial blood vessel and the dura mater.

29. The device of claim 24, wherein the shaft further comprises an offset configured to orient the perforating element in a direction toward the wall of the intracranial vessel and the dura mater when the proximal portion of the shaft faces the patient's skull.

30. The device of claim 29, wherein the offset has a non-circular cross-sectional shape configured to bend preferentially in a first plane rather than a second plane.

31. The device of claim 24, wherein the shaft further comprises a wider section having a lateral dimension equal to or substantially equal to an inner diameter of the lumen of the aspiration catheter to prevent ovalization of the aspiration catheter when the aspiration catheter is advanced through the longitudinal slit.

32. The device of claim 31 , wherein the wider section is disposed proximal to the curved section.

33. A device according to claim 31, wherein the distal end of the aspiration catheter includes a first non-transmissive element and the shaft includes a second non-transmissive element disposed adjacent the wider section so that the wider section can be aligned with the distal end of the aspiration catheter before advancing the aspiration catheter through the longitudinal slit.

34. The device of claim 24, wherein the shaft comprises a first radiopaque element disposed at the perforating element and a second radiopaque element disposed proximal to the curved segment, the first radiopaque element and the second radiopaque element being configured to facilitate confirmation of the configuration of the curved segment.

35. The device of claim 34, wherein the perforated element and the first radiopaque element form an angle of between about 5° and about 15° relative to the second radiopaque element when the curved section is in the curved configuration.

36. The device of claim 24, wherein the shaft further comprises a proximal section having an outer diameter that varies along the length of the proximal section.

37. The device of claim 36, wherein the proximal section tapers from a first outer diameter to a second outer diameter for a length between about 4 mm and about 6 mm.

38. The apparatus of claim 37, wherein the first outer diameter is substantially equal to the inner diameter of the aspiration catheter to limit the length of the axial distal advancement beyond the distal end of the aspiration catheter.

39. A device for draining a subdural hematoma disposed in an extracranial space of a patient's intracranial blood vessel, the device comprising: a suction catheter, the suction catheter being capable of being disposed within an intracranial blood vessel of the patient, the suction catheter defining a lumen; as well as a shaft configured to be advanced through the lumen of the suction catheter until a distal tip portion of the shaft is disposed within the intracranial vessel, the shaft comprising: a perforating element disposed at a distal end of the distal tip portion, the perforating element being configured to cut through a wall and dura mater of the intracranial blood vessel of the patient to create a passage from the intracranial blood vessel into an extracranial lumen of the intracranial blood vessel, The perforating element is configured to be angled relative to the distal tip portion, When the perforating element is arranged to extend distally beyond the distal end of the suction catheter, the perforating element can be guided toward the wall and the dura mater of the intracranial blood vessel and cut through the wall and the dura mater of the intracranial blood vessel at an oblique angle. The suction catheter is configured to be advanced through the passageway and to the subdural hematoma to allow fluid or material from the subdural hematoma to be drained out of the intracranial extravascular space via the lumen of the catheter.

40. The apparatus of claim 39, wherein the perforating element forms an angle of between about 1° and about 90° relative to the distal tip portion when the perforating element is disposed distally beyond the distal end of the suction catheter.

41. The device of claim 39, wherein the suction catheter comprises a proximal end configured to be coupled to a suction source such that the suction source can apply suction to the lumen to drain the fluid or material from the subdural hematoma.

42. The device of claim 39, wherein the perforating element has an atraumatic shape.

43. The device of claim 39, wherein the shaft further comprises an offset configured to orient the perforating element in a direction toward the wall of the intracranial vessel and the dura mater when the proximal portion of the shaft faces the patient's skull.

44. The device of claim 39, wherein the shaft further comprises a wider section having a lateral dimension equal to or substantially equal to an inner diameter of the lumen of the aspiration catheter to prevent ovalization of the aspiration catheter when the aspiration catheter is advanced through the longitudinal slit.

45. The device of claim 39, wherein the shaft further comprises a proximal segment having an outer diameter tapering from a first outer diameter substantially equal to the inner diameter of the aspiration catheter to a second outer diameter such that the proximal segment is configured to limit the length to which the shaft can be advanced distally beyond the distal end of the aspiration catheter.

46. ​​A device for draining a subdural hematoma disposed in an extracranial space of a patient's intracranial blood vessel, the device comprising: a suction catheter, the suction catheter being capable of being disposed within an intracranial blood vessel of the patient, the suction catheter defining a lumen; as well as a shaft configured to be advanced through the lumen of the suction catheter until a distal tip portion of the shaft is disposed within the intracranial vessel, the shaft comprising: a puncturing element configured to cut through a wall and dura mater of the intracranial blood vessel of the patient to create a passage from the intracranial blood vessel into an extracranial lumen of the intracranial blood vessel; a curved section having a predetermined curvature, the curved section being configured to be radially constrained within the lumen of the suction catheter and to curve toward the wall of the intracranial blood vessel and the dura mater when exiting the lumen of the catheter; a discontinuity disposed proximal to the curved section, the discontinuity being configured to orient the predetermined curvature of the curved section to follow the curvature of the intracranial blood vessel when the shaft is advanced through the lumen of the aspiration catheter, The suction catheter is configured to be advanced through the passageway and to the subdural hematoma to allow fluid or material from the subdural hematoma to be drained out of the intracranial extravascular space via the lumen of the catheter.

47. The device of claim 46, wherein the discontinuity is a first discontinuity and the shaft includes a second discontinuity at a location between the perforated element and the curved section. Discontinuity.

48. The device of claim 47, wherein the second discontinuity comprises a bend in the shaft configured to direct the perforating element toward the wall of the intracranial vessel and the dura mater.

49. The device of claim 47, wherein the predetermined curvature of the curved segment has a first radius of curvature, and the second discontinuity comprises a segment of the shaft having a second radius of curvature that is smaller than the first radius of curvature.

50. The device of claim 46, wherein the curved segment has a cross-section having a first lateral dimension that is greater than a second lateral dimension.

51. The device of claim 46, wherein the discontinuity comprises a bend in the shaft.

52. The device of claim 46, wherein the discontinuity comprises a partial helix or twist in the shaft.

53. The device of claim 46, wherein the curved segment is a first curved segment comprising a convex curvature, and the shaft further comprises a second curved segment proximal to the first curved segment, the second curved segment comprising a concave curvature.

54. An apparatus comprising: a shaft configured to be slidably disposed within a lumen of a catheter, the shaft configured to be disposed distally from a distal end of the catheter and into a blood vessel of a subject, the shaft comprising: a puncture tip comprising an energy element configured to generate radiofrequency (RF) energy to form an opening through a wall and dura mater of the blood vessel of the subject and into an extravascular lumen of the subject; a curved segment configured to be radially constrained within the lumen of the catheter, the curved segment configured to bend toward the wall of the blood vessel and the dura mater upon exiting the lumen of the catheter such that the energy element is positioned to form the opening; a first discontinuity disposed between the perforated end and the curved section; and A second discontinuity is disposed proximal to the curved section, the second discontinuity being configured to orient the curve to follow the curve of the blood vessel when the shaft is advanced within the lumen of the catheter.

55. The device of claim 54, wherein the first discontinuity comprises a bend in the shaft.

56. The device of claim 54, wherein the curved segment has a first radius of curvature and the first discontinuity comprises a segment of the shaft having a second radius of curvature that is smaller than the first radius of curvature.

57. The device of claim 54, wherein the curved segment is configured to transition into a curved configuration as the curved segment travels through the opening and into the extravascular cavity.

58. The device of claim 54, wherein the curved segment has a cross-section having a first lateral dimension that is greater than a second lateral dimension.

59. The device of claim 54, wherein the second discontinuity comprises a bend in the shaft.

60. The device of claim 54, wherein the second discontinuity comprises a partial helix or twist in the shaft.

61. The device of claim 54, wherein the curved segment is a first curved segment comprising a convex curvature, and the shaft further comprises a second curved segment proximal to the first curved segment, the second curved segment comprising a concave curvature.

62. The device of claim 54, wherein the shaft includes a wider section having a lateral dimension equal to or substantially equal to an inner diameter of the lumen of the catheter to prevent ovalization of the catheter when the catheter is advanced through the opening.

63. The device of claim 54, wherein the length of the opening is equal to or substantially equal to the length of the energy element.

64. A system comprising: a catheter having a proximal end and a distal end and defining a lumen therebetween, the distal end of the catheter being configured to be positioned within a blood vessel of a subject; as well as a shaft slidably disposed within the lumen, the shaft comprising a perforated tip having an energy element configured to generate radio frequency (RF) energy to penetrate a wall and dura mater of the blood vessel of the subject, the shaft further comprising a bending section configured to transition from a radially constrained configuration to a bent configuration, The shaft is configured to be advanced along the catheter such that the curved segment is oriented to curve along the curve of the blood vessel and away from the distal end of the catheter, and the curved segment is configured to curve toward the wall of the blood vessel such that the perforating tip is positioned against the wall of the blood vessel and is capable of penetrating the wall of the blood vessel and the dura mater and entering the extravascular lumen when the energy element is activated.

65. The system of claim 64, wherein the distal end of the catheter comprises a radiopaque element.

66. The system of claim 65, wherein the shaft comprises a first radiopaque element disposed at the perforated tip and a second radiopaque element disposed proximal to the curved section.

67. The system of claim 64, wherein the catheter is configured to be advanced over the shaft into the extravascular lumen, The shaft also includes a wider section disposed proximal to the curved section, the wider section preventing ovalization of the catheter when the catheter is advanced into the extravascular lumen.

68. A system according to claim 67, wherein the distal end of the catheter includes a first non-transmissive element and the shaft includes a second non-transmissive element disposed adjacent the wider segment so that the wider segment can be aligned with the distal end of the catheter prior to advancing the catheter into the extravascular cavity.

69. The system of claim 64, wherein the shaft is a first RF device, the system further comprising a second RF device comprising a linear tip configured to penetrate a membrane of a subdural hematoma.

70. The system of claim 69, wherein the second RF device is configured to deliver RF energy to close the vessel lumen of the blood vessel.

71. A method comprising: positioning a distal end of a catheter disposed within an intracranial blood vessel of a subject proximate to a target location; advancing a shaft through the lumen of the catheter such that a curved section of the shaft bends in a direction that follows the curve of the blood vessel, the curved section being constrained within the lumen of the catheter; extending the curved section of the shaft out of the distal end of the catheter so that the curved section bends toward a wall of the blood vessel, and positioning a radio frequency (RF) element disposed at the distal end of the shaft against the wall of the blood vessel; activating the radio frequency (RF) element to deliver RF energy to the wall of the blood vessel to create an opening through the wall and dura mater of the blood vessel and into an extravascular intracranial cavity of the subject; advancing the distal end of the shaft into the extravascular intracranial cavity until the curved segment transitions to an unconstrained configuration within the extravascular intracranial cavity; and The catheter is advanced over the shaft and into the extravascular intracranial cavity.

72. The method of claim 71 , further comprising: advancing the distal end of the shaft into a subdural hematoma; as well as advancing the catheter over at least a portion of the shaft and into the subdural hematoma; as well as After the catheter is positioned within the subdural hematoma, suction is applied to the lumen of the catheter to remove fluid from the subdural hematoma.

73. The method of claim 71 , further comprising: withdrawing the catheter toward the opening created in the wall of the artery; as well as A hemostatic element or RF device is delivered through the lumen of the catheter to close the opening.

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