Systems and methods for endovascular treatment of hydrocephalus and elevated intracranial pressure

Abstract

A delivery system for deploying an implant includes a delivery catheter, tissue penetrating elements (350) disposed at an open distal end of the delivery catheter, and a guard member (400) including a proximal portion disposed over and movable relative to each tissue penetrating element and the distal end of the delivery catheter, the guard member (400) defining a lumen (405) configured to receive and cover the tissue penetrating elements (350), the lumen defining a longitudinal axis of the guard member, the proximal portion of the guard member transitioning to a split open distal portion adjacent the distal opening of the lumen, the split open distal portion including a contour configured to engage the tissue penetrating elements and deflect the tissue penetrating elements at an angle relative to the longitudinal axis of the guard member when the guard member moves proximally relative to the tissue penetrating elements.

Description

[Technical field]

[0001] The invention disclosed herein relates to improved systems and methods for accessing the subarachnoid space and draining cerebrospinal fluid (CSF) (e.g., for relieving elevated intracranial pressure or treating normal pressure hydrocephalus) using an endovascular approach. More particularly, the present disclosure relates to systems and methods for the treatment of hydrocephalus, pseudotumor cerebri and / or intracranial hypertension.

[0002] Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 320,621, filed March 16, 2022, the entire disclosure of which is expressly incorporated herein by reference. [Background technology]

[0003] The development and practice of minimally invasive surgical devices and procedures has made great advances in recent decades. As used herein, "minimally invasive" refers to the use of surgical devices and implants that access the body via the vascular system via arterial or venous access in the groin, arm or neck, as opposed to more invasive conventional procedures that access the body percutaneously / through incisions in solid tissue and more directly by cutting and / or drilling bones as necessary to access the internal regions of the body where the procedure is performed. Minimally invasive may also refer to the use of surgical devices and implants that access the body via other natural body openings, cavities and tubular structures, such as the esophagus, intestine, bronchi, etc. Percutaneous access to solid tissue through the skin, such as using trocars and stylets to access the liver, prostate or lungs, for example, is also considered minimally invasive.

[0004] Examples of minimally invasive surgical devices and procedures for relieving elevated intracranial pressure or treating normal pressure hydrocephalus are described in U.S. Pat. Nos. 10,272,230 and 10,765,846, and U.S. Patent Application Publication No. 20200030588A1, the entire disclosures of which are incorporated by reference into this specification as if set forth in full.

[0005] However, there continues to be a need for improved minimally invasive neurosurgical devices capable of deploying devices designed to access the intracranial subarachnoid space ("SAS") and drain cerebrospinal fluid from the SAS into the venous system. The complexity of the device preparation procedure, the impact of the preparation procedure on the device, and the time required to prepare a minimally invasive system for clinical use are important considerations, and it is desirable to simplify such preparation to be completed in less than an hour, preferably less than 15 minutes. Improvements are also needed to improve the user experience by simplifying the device deployment procedure and reducing risks to patient safety during minimally invasive procedures. Additionally, improvements are also needed to increase the manufacturability of minimally invasive neurosurgical devices so that the devices can be manufactured at low cost and in large quantities to realize commercialization of the technology. Summary of the Invention

[0006] A delivery system for deploying an implant is provided that includes a delivery catheter including a first delivery catheter lumen extending from an open distal end of the delivery catheter into a handle coupled to a proximal end portion of the delivery catheter, and tissue penetrating elements disposed at the open distal end and extending distally therefrom, the delivery system further including a guard member including a proximal portion disposed over and movable relative to each tissue penetrating element and the distal end of the delivery catheter, the guard member defining a guard member lumen configured to receive and cover the tissue penetrating element, the guard member lumen defining a longitudinal axis of the guard member. The guard member proximal portion transitions to a split opening distal portion adjacent the distal opening of the guard member lumen, the split opening distal portion including a contour configured to engage the tissue penetrating element and deflect the tissue penetrating element at an angle relative to a longitudinal axis of the guard member when the guard member moves proximally relative to the tissue penetrating element, the guard member split opening distal portion comprising arcuate angled portions on either side of the contour having respective surfaces configured to engage and deflect the tissue penetrating element. The guard member split opening distal portion contour is preferably configured to allow the respective angled portions on either side to open and fold around the tissue penetrating element when the respective guard members and delivery catheter are retracted into the guide catheter.

[0007] The delivery system may further include a pull wire coupled to the guard member and configured to move the guard member proximally relative to the tissue penetrating element. The pull wire may have a rectangular, circular, or crescent cross-sectional profile. The pull wire also bifurcates into respective first and second pull wire members. The pull wire further includes an arc-shaped radiopaque marker embedded within the guard member adjacent a distal opening of the guard member lumen, the first and second pull wire members being respectively attached to the arc-shaped radiopaque marker. The guard member further includes a second guard member lumen spanning between a proximal portion and a distal portion of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member moves, the second guard member lumen being partially surrounded by the arc-shaped marker.

[0008] Additionally, the delivery catheter includes a second delivery catheter lumen, a pull wire disposed within the second delivery catheter lumen, and the handle further includes a flush port in fluid communication with the first catheter lumen and a tether actuation mechanism, a proximal end of the pull wire coupled to the tether actuation mechanism configured to be pulled relative to the handle, thereby moving the guard member relative to the tissue penetrating element, thereby exposing the tissue penetrating element.

[0009] Optionally, a distal portion of the pull wire is embedded within the guard member. An arc-shaped radiopaque marker can be embedded within the guard member adjacent a distal opening of the guard member lumen. The guard member having a first guard member lumen also includes a second guard member lumen spanning between the proximal and distal portions of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member travels, the second guard member lumen being partially surrounded by the arc-shaped marker.

[0010] Optionally, an elongated radiopaque marker spine is embedded in the tissue penetrating element, the marker spine being aligned substantially parallel to a longitudinal axis of the tissue penetrating element, and configured such that when the tissue penetrating element is positioned within the guard member lumen, the arc-shaped radiopaque marker embedded in the guard member and the radiopaque marker spine embedded in the tissue penetrating element indicate the position, orientation and trajectory of the tissue penetrating element.

[0011] Also provided is a delivery system for deploying an implant, the delivery system including a delivery catheter having a proximal opening, a distal opening, and a delivery catheter lumen extending therebetween. The delivery system further includes a shroud assembly including an elongated tubular shroud body having open proximal and distal ends, an implant retaining feature coupled to the proximal end of the shroud body, the implant retaining feature having a proximal end and an open distal end, and a shroud lumen extending through the shroud body from the opening at the distal end of the shroud body, the opening at the proximal end of the shroud body, and an interior of the implant retaining feature, respectively. The delivery catheter lumen is configured to receive the shroud assembly therein and allow passage of the shroud assembly, and the implant retaining feature is configured to secure a proximal end portion of the implant within the shroud assembly when an implant is disposed in the shroud lumen and the shroud assembly is disposed within the delivery catheter lumen. The implant retaining feature is configured to release a proximal end portion of the implant when the shroud assembly is advanced out of the delivery catheter lumen through a distal opening of the delivery catheter. A delivery wire may be coupled to the proximal end of the implant retaining feature and configured to advance or retract the shroud assembly within the delivery catheter lumen with the implant disposed within the shroud lumen.

[0012] Optionally, the implant retaining feature includes a plurality of elongated members extending between two annular members, the elongated members including respective protrusions facing radially outward, such that when the implant is placed within the shroud lumen and the shroud assembly is placed within the delivery catheter lumen, the protrusions are compressed by an inner wall of the delivery catheter lumen, thereby compressing the elongated members against a proximal end portion of the implant, thereby gripping the implant within the shroud lumen.

[0013] The shroud body further includes a helically cut hypotube and an uncut axial spine disposed along the length of the hypotube. The shroud assembly also includes a proximal radiopaque marker disposed at the proximal end of the implant retention feature and a distal radiopaque marker disposed at the opening at the distal end of the shroud body. The distal radiopaque marker includes an annular edge configured to contact an annular edge of the implant distal anchor mechanism to advance the implant through the delivery catheter lumen and out the distal end opening of the delivery catheter.

[0014] Further provided is a transfer device for flushing and transferring an implant into a delivery catheter, the implant transfer device comprising an elongate housing, an implant transfer lumen extending through the housing from a proximal opening of the housing to a distal opening of the housing, a distal Luer connector coupled to the distal opening, a Touhy-Borst adapter and stopcock coupled to the proximal opening, and an annular passive seal disposed within the implant transfer lumen, the annular passive seal including a lumen configured to hold an expandable portion of the implant in a compressed configuration, and the distal Luer connector, the implant transfer lumen, the passive seal lumen, the Touhy-Borst adapter and the stopcock are in fluid communication.

[0015] Additionally, the transfer device can have a shroud assembly disposed in the implant transfer lumen, the shroud assembly including an elongated tubular shroud body having open proximal and distal ends, an implant retaining feature coupled to the proximal end of the shroud body, the implant retaining feature having a proximal end and an open distal end, and a shroud lumen extending from an opening at the distal end of the shroud body, an opening at the proximal end of the shroud body, and an interior of the implant retaining feature through the shroud body, respectively, a body portion of the implant disposed within the shroud lumen, a proximal portion of the implant disposed within the retaining feature, a distal anchor mechanism of the implant disposed in a compressed configuration within the passive seal lumen, and a distal luer connector of the transfer device, the implant transfer lumen, the passive seal lumen, the lumen of the implant, and the Twi Borst adapter and stopcock of the transfer device are in fluid communication.

[0016] Optionally, the shroud assembly further comprises a delivery wire coupled to a proximal end of the implant retaining feature and configured to advance or retract the shroud assembly within the implant transport lumen with the implant disposed within the shroud lumen. The implant retaining feature may also comprise a plurality of elongated members extending between two annular members, the elongated members including respective projections facing radially outward. The shroud body may comprise a helically cut hypotube and an uncut axial spine disposed along the length of the hypotube. The shroud assembly further comprises a proximal radiopaque marker disposed at the proximal end of the implant retaining feature and a distal radiopaque marker disposed at an opening at the distal end of the shroud body. Optionally, the delivery device further comprises a tubular support member disposed in the implant delivery lumen, the tubular support member defining an inner lumen through which the shroud assembly and the implant retained therein are advanced, such that a distal portion of the tubular support member tapers radially inward in a distal direction, such that an inner diameter of the lumen of the tubular support member decreases distally along a length of the distal portion, and such that as the shroud assembly and implant are advanced distally through the lumen of the tubular support member, the shroud retaining feature is compressed, thereby securing or gripping a proximal end portion of the implant.

[0017] An assembly for verifying patency of a shunt implant prior to clinical use is provided, the assembly comprising a base, a three-way stopcock secured to the base, the three-way stopcock having a plurality of Luer fittings, a first stopcock Luer fitting connectable to a fluid source (e.g., a syringe), a fluid column in fluid communication with the second stopcock Luer fitting, and a flushing line having a distal end opening in fluid communication with the third stopcock Luer fitting, the flushing line further having a proximal end opening.

[0018] The stopcock has a first open position that places the fluid source in fluid communication with the flushing line, a second open position that places the fluid source in fluid communication with the fluid column, and a third open position that places the fluid column in fluid communication with the flushing line. The base can include a hinge mechanism secured to the stopcock, the hinge mechanism configured to pivot the stopcock and the fluid column from a first position in which the fluid column is disposed substantially parallel to a surface of the base to a second position in which the fluid column is disposed substantially perpendicular to the surface of the base. The hinge mechanism can be configured to releasably secure the stopcock in the second position.

[0019] A method of preparing a shunt implant for clinical use is provided, the method comprising connecting flushing lines of the above-mentioned assembly to the distal luer connector of the above-mentioned implant transfer device to fluidly communicate the flushing lines with the lumens of the shunt. The stopcocks are then placed in a first open position, and fluid from the fluid source is pumped through the respective flushing lines and the implant lumens. The stopcocks are then placed in a second open position, and fluid from the fluid source is pumped into the fluid column. The stopcocks are then placed in a third open position, and the flow of fluid from the fluid column through the respective flushing lines and the shunt lumens can be confirmed by observing the fluid exiting the stopcock of the implant transfer device. The passive annular seal of the implant transfer device directs the fluid flow of the implant transfer device lumens into the shunt lumen. Furthermore, the flushing lines can be disconnected from the distal luer connector of the implant transfer device, and then the distal luer connector of the implant transfer device can be connected to the proximal luer connector of the delivery catheter handle, and the shunt implant can be advanced through the lumen of the implant transfer device into the lumen of the delivery catheter. The fluid source may be a syringe and the fluid may be heparinized saline.

[0020] Optionally, advancing the shunt implant through the implant delivery device lumen and into the lumen of the delivery catheter includes advancing the implant and shroud assembly with a pusher wire. Also, when advancing the implant and shroud assembly from the delivery device lumen into the delivery catheter lumen, the plurality of protrusions of the proximal retention feature compress the elongated member of the retention feature to grip a proximal portion of the implant. Furthermore, when advancing the implant and shroud assembly through the delivery device lumen and into the delivery catheter lumen, an annular edge of the shroud distal radiopaque marker of claim 25 contacts an annular edge of the implant distal anchor mechanism to advance the implant through the delivery tool lumen and into the delivery catheter lumen.

[0021] Also provided is a catheter comprising: a first catheter lumen extending from an open distal end of the catheter into a handle coupled to a proximal end portion of the catheter; tissue penetrating elements disposed at and extending distally from the open distal end of the catheter; and a guard member disposed over each tissue penetrating element and the distal end of the catheter and including a proximal portion movable relative to the tissue penetrating elements and the distal end of the catheter, the guard member defining a guard member lumen configured to receive and cover the tissue penetrating elements, the guard member lumen defining a longitudinal axis of the guard member, the proximal portion of the guard member transitioning to a split open distal portion adjacent a distal opening of the guard member lumen, the split open distal portion including a contour configured to engage the tissue penetrating elements and deflect the tissue penetrating elements at an angle relative to the longitudinal axis of the guard member when the guard member moves proximally relative to the tissue penetrating elements. The split-opening distal portion of the guard member includes an arcuate beveled portion on either side of a contour having a respective surface configured to engage and deflect the tissue-penetrating element. The contour of the split-opening distal portion of the guard member is configured to allow the respective beveled portions to open and collapse around the tissue-penetrating element when the respective guard member and the catheter are retracted into the guide catheter. The catheter can also include a pull wire coupled to the guard member and configured to move the guard member proximally relative to the tissue-penetrating element. The pull wire includes a rectangular, circular, or crescent cross-sectional profile. The distal portion of the pull wire bifurcates into respective first and second pull wire members. The catheter also includes an arcuate radiopaque marker embedded within the guard member adjacent the distal opening of the guard member lumen, the first and second pull wire members being respectively attached to the arcuate radiopaque marker.

[0022] Further, in this catheter, the guard member lumen includes a first guard member lumen, the guard member further includes a second guard member lumen spanning between a proximal portion and a distal portion of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member travels, and the second guard member lumen is partially surrounded by an arcuate marker. Optionally, the catheter further includes a second catheter lumen, a pull wire disposed within the second delivery catheter lumen, the handle further includes a flush port in fluid communication with the first catheter lumen and a tether actuation mechanism, a proximal end of the pull wire coupled to the tether actuation mechanism configured to be pulled relative to the handle to thereby move the guard member relative to the tissue penetrating element, thereby exposing the tissue penetrating element, and a distal portion of the pull wire embedded within the guard member. The pull wire further includes an arc-shaped radiopaque marker embedded within the guard member adjacent a distal opening of the guard member lumen. The guard member lumen has a first guard member lumen, the guard member further having a second guard member lumen spanning between a proximal portion and a distal portion of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member travels, the second guard member lumen being partially surrounded by the arc-shaped marker. Additionally, the catheter can have elongate radiopaque marker spines embedded in the tissue penetrating element, the marker spines aligned substantially parallel to a longitudinal axis of the tissue penetrating element, and configured to indicate a position, orientation and trajectory of the tissue penetrating element when the tissue penetrating element is disposed within the guard member lumen.

[0023] A shroud assembly for delivering an implant through a catheter lumen is provided, the shroud assembly including an elongated tubular shroud body having open proximal and distal ends, an implant retaining feature coupled to the proximal end of the shroud body, the implant retaining feature having a proximal end and an open distal end, and a shroud lumen extending through the shroud body from an opening at the distal end of the shroud body, an opening at the proximal end of the shroud body, and an interior of the implant retaining feature, the implant retaining feature configured to secure a proximal end portion of the implant within the shroud assembly when an implant is disposed in the shroud lumen and the shroud assembly is disposed within the catheter lumen, the implant retaining feature configured to release the proximal end portion of the implant when the shroud assembly is advanced out of the distal end opening of the catheter lumen. The shroud assembly can also include a delivery wire coupled to a proximal end of the implant retention feature and configured to advance or retract the shroud assembly within the delivery catheter lumen with the implant disposed within the shroud lumen.

[0024] Optionally, the implant retaining feature may comprise a plurality of elongated members extending between two annular members, the elongated members including respective projections facing radially outward, such that when an implant is disposed within the shroud lumen and the shroud assembly is disposed within the catheter lumen, the projections are compressed by an inner wall of the catheter lumen, thereby compressing the elongated members against a proximal end portion of the implant, thereby gripping the implant within the shroud lumen. The shroud body may comprise a helically cut hypotube and an uncut axial spine disposed along the length of the hypotube. The shroud assembly may also comprise a proximal radiopaque marker disposed at the proximal end of the implant retaining feature and a distal radiopaque marker disposed at a distal end opening of the shroud body.

[0025] Other and further aspects and features of the embodiments will become apparent from the following detailed description when considered in conjunction with the accompanying drawings. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a side view of a delivery assembly according to an embodiment of the disclosed invention. [Diagram 2] 2A-2D are perspective, top and side views of a delivery catheter having a piercing element guard according to an embodiment of the disclosed invention. [Diagram 3] 3A to 3F are a side view, a perspective view, and a cross-sectional view of a guard member and a pull wire according to an embodiment of the disclosed invention. [Figure 4] 4A and 4B are side views of an interface between a delivery catheter having a piercing element and the guard member of FIGS. 3A-3F according to an embodiment of the disclosed invention. [Diagram 5] 5A-5C are down-the-barrel views of the interface between a delivery catheter having a piercing element according to an embodiment of the disclosed invention and the guard member of FIGS. 3A-3F, 4A, and 4B. [Figure 6] 6A and 6B are side and perspective views of a distal portion of a delivery catheter having a piercing element, and FIGS. 6C-6N are top and side views of an alternative embodiment of the piercing element. [Figure 7] 7A-7D are side views of a shunt / implant and shroud according to an embodiment of the disclosed invention. [Figure 8] 8A-8F are side and detailed views illustrating operation of the shroud along with a shunt / implant according to an embodiment of the disclosed invention. [Figure 9] 9A-9E are perspective and cross-sectional views of a shroud according to an alternative embodiment of the disclosed invention. [Figure 10] 10A-10E are perspective, detailed and cross-sectional views of a shunt / implant according to an embodiment of the disclosed invention. [Figure 11] 11A-11C are perspective and down-the-barrel views of an anchor, a proximal radiopaque marker and an elongate guide member according to an embodiment of the disclosed invention. [Figure 12] 12A and 12B are perspective and down-the-barrel views of a proximal radiopaque marker of the anchor of FIGS. 11A-11C according to an embodiment of the disclosed invention. [Figure 13] FIG. 13 is a cross-sectional view of a handle of the delivery catheter of FIG. 16A according to an embodiment of the disclosed invention. [Figure 14] 14A-14D are perspective and cross-sectional views of one embodiment of a handle for the delivery catheter of FIG. 2, according to an embodiment of the disclosed invention. [Figure 15] 15A-15F are perspective, cross-sectional and detailed views of a delivery device according to an embodiment of the disclosed invention, and FIG. 15G is a cross-sectional view of a passive seal according to an embodiment of the disclosed invention. [Figure 16] FIG. 16A is a perspective view of the delivery device of FIGS. 15A-15C coupled to the handle of FIG. 13, and FIG. 16B is a perspective view of the delivery device of FIGS. 15D-15G coupled to the handle of FIGS. 14A-14D, according to an embodiment of the disclosed invention. [Figure 17] 17A and 17B are perspective and top views of the reservoir assembly and transfer device of FIGS. 15A-15C and 16A according to an embodiment of the disclosed invention. [Figure 18] FIG. 18 is a flow chart of a patency test according to an embodiment of the disclosed invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.

[0028] All numerical values ​​herein are intended to be modified by the term "about," whether or not expressly stated. The term "about" generally refers to a range of numerical values ​​that one of ordinary skill in the art would consider equivalent to the recited value (i.e., having the same function or result). In many instances, the term "about" can include numerical values ​​that are rounded to the nearest significant figure.

[0029] The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0030] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates. As used in this specification and the appended claims, the term "or" is typically used in its sense to include "and / or" unless the content clearly dictates.

[0031] Various embodiments will now be described with reference to the drawings. The drawings are not necessarily drawn to scale, and the relative scale of selected elements may be exaggerated for clarity, with elements of similar structure or function being designated by similar reference numerals throughout the drawings. Additionally, the drawings are intended only to facilitate the description of the embodiments, and are not intended as an exhaustive description of the invention or as limiting the scope of the invention, which is defined only by the appended claims and their equivalents. Furthermore, an illustrated embodiment need not have all aspects or advantages disclosed. An aspect or advantage described in connection with a particular embodiment is not necessarily limited to that embodiment, and may be implemented in other embodiments, even if not so shown.

[0032] FIG. 1 is a side view of a delivery assembly 300 according to an embodiment of the disclosed invention for accessing the subarachnoid space and / or delivering an intravascular cerebrospinal fluid (CSF) implant (e.g., shunt, implant / shunt) to a target site in a patient. The delivery assembly 300 can include an anchor 700 (not shown) and a shunt (not shown) removably coupled to the delivery assembly 300. The delivery assembly 300 and the shunt can be constructed of suitable biocompatible materials. The delivery assembly 300 is sized to reach remote locations in the vasculature and configured to deliver the shunt percutaneously to a target location (e.g., cerebellopontine angle cistern (CP-pontine angle cistern), inferior petrosal sinus (IPS)). The delivery assembly 300 includes a tubular member interface having an outer tubular member 320 (i.e., a guide catheter) and an inner tubular member 304 (i.e., a delivery catheter / microcatheter) coaxially disposed within the outer tubular member 320 and movable relative to the outer tubular member 320. Delivery assembly 300 can include a guidewire 302 coaxially disposed within guide catheter 320 and / or delivery catheter 304. Guidewire 302 can be, for example, 0.035 inches (0.889 mm) in diameter. In addition to guidewire 302, delivery assembly 300 can include a delivery wire 308 disposed within delivery catheter 304. Delivery wire 308 has a smaller diameter (e.g., about 0.010 inches (0.254 mm) to 0.018 inches (0.4572 mm) or other suitable dimensions to facilitate access to the intracranial venous vasculature by other components of delivery assembly 300) compared to guidewire 302.

[0033] The guide catheter 320, delivery catheter 304 and guidewire 302 / 308 (FIG. 1) may be formed of suitable biocompatible materials and may include markings 13 for imaging purposes (e.g., markers constructed of radiopaque materials). Various known and often necessary accessories of the delivery assembly 300 are shown in FIG. 1, such as one or more radiopaque marker bands 13 at the distal portion 324 of the guide catheter 320 to allow viewing of the location of the distal portion under fluoroscopy, and a luer assembly 17 for guidewire and / or fluid access. The delivery assembly 300 and / or shunt may include a piercing element (not shown) configured to puncture and / or penetrate the venous sinus wall (e.g., the IPS wall and arachnoid layer for accessing the CP-pontine angle cistern). The delivery catheter 304 facilitates guidance and delivery of the shunt to a target deployment location through the patient's vasculature, with or without a delivery guidewire.

[0034] FIG. 2A shows a side view of a delivery catheter 304 according to another embodiment of the present invention. Instead of the luer assembly 17 of FIG. 1, the delivery catheter 304 is coupled and / or integrated with the handle 10 as shown in FIG. 2A. The handle 10 includes a luer fitting 12, a delivery lumen flush port 14, a tether retraction mechanism 18, and a strain relief mechanism 19, which are further described in FIGS. 13-14C below. The delivery catheter 304 includes a proximal portion 324, which may be coupled and / or integrated with the handle 10 via the strain relief mechanism 19. The delivery catheter 304 further includes a distal portion 344 (detailed view of FIG. 2B), which includes a piercing element 350 disposed within a guard member 400, which is further described in FIGS. 2B-2D below. An embodiment of the delivery catheter 304 may include a multi-layer structure. For example, the delivery catheter 304 can be manufactured with a reinforcing member, such as a hypotube, having regions of differing flexibility (e.g., intermittent spiral cuts, selective slots, perforations, etc.), where the reinforcing member inner surface is coated, dipped, or covered with a lubricious material, such as a PTFE lining, and the reinforcing member outer surface is coated, dipped, or covered with a polymeric jacket, as described, for example, in U.S. Pat. Nos. 10,272,230, 10,765,846, and U.S. Patent Application Publication No. 20200030588A1.

[0035] 2B-2D are perspective, side, and top views of a distal portion 344 of a delivery catheter 304 of a delivery assembly 300 according to an embodiment of the present invention. The delivery assembly 300 comprises a delivery catheter 304 and a piercing element guard or guard member 400. In some embodiments, the distal portion 344 of the delivery catheter 304 includes an elongated tubular shaft 344a and a distal end 344b, the distal end 344b being coupled to or including a piercing element 350. As shown in FIGS. 2A-2D, the guard member 400 is configured to cover the piercing element 350, which is further shown in FIG. 4A disposed within the guard member 400. The guard member 400 covers the piercing element 350 while the delivery catheter 304 is guided through the patient's vasculature to a target penetration site (e.g., a venous sinus wall). Additionally, the guard member 400 is configured to fold around the shaft 344a of the delivery catheter 304 during withdrawal of the catheter 304, as described and illustrated in FIGS. 5A-5C. In an alternative embodiment, the guard member 400 may cover the penetrating element 350 during withdrawal of the delivery catheter 304 after accessing the subarachnoid space or deploying the shunt, thereby preventing inadvertent puncture or damage to other components of the delivery assembly (e.g., the guide catheter) and / or the patient's vasculature. As shown in FIG. 2B, the delivery catheter 304 includes a first lumen 305 configured to receive and / or accommodate the shunt. The guard member 400 includes a first lumen 405 configured to receive the penetrating element 350 and a second lumen 415 configured to receive and / or accommodate the elongated guide member 780, as shown in FIG. 2B.

[0036] 3A-3F show a guard member 400 according to an embodiment of the present invention. The guard member 400 includes a pull wire 410 that bifurcates into two elongated portions 410a, 410b at a distal section 411 of the pull wire 410, as shown in FIG. 3E. The bifurcated pull wire portions 410a, 410b can be manufactured by laser cutting the distal section 411 of the pull wire 410, or by any other suitable technique. The two elongated portions 410a, 410b of the pull wire 410 are attached to an arc-shaped (e.g., partially cylindrical or semi-cylindrical in form, non-annular) radiopaque marker 425, as shown in FIG. 3E. Elongated portions 410a, 410b of pull wire 410 are embedded or encapsulated within guard member 400 and include respective distal tips 412a, 412b, each of which is coupled (e.g., coupled to the attachment section by welding or other suitable technique) to an arc-shaped radiopaque marker 425 (FIG. 3E), which is embedded or encapsulated within guard member 400.

[0037] 2C and 2D , the delivery catheter 304 includes a lumen 322 configured to receive and / or house the pullwire 410. The delivery catheter 304 includes a lubricious liner (e.g., PTFE, etc.) that lines the inner wall (not shown) of the lumen 322 to increase lubricity and / or reduce friction of the pullwire 410 within the lumen 322 of the delivery catheter 304, thereby facilitating smooth proximal and / or distal movement, translation and / or actuation of the guard member 400 to expose and re-cover the piercing element 350.

[0038] 3A-3F are configured to translate guard member 400 proximally and / or distally relative to delivery catheter 304 to at least partially expose or cover piercing element 350, respectively. Because bifurcated pullwire portions 410a, 410b are coupled to substantially opposite sides of guard member 400, bifurcated portions 410a, 410b are further configured to evenly transfer translation forces (e.g., pull and / or push) to guard member 400. As a result, pullwire 410 can provide smoother torqueing, advancement and / or retraction of guard member 400 over piercing element 350 compared to a single pullwire without distal bifurcated portions 410a, 410b or compared to two separate pullwires extending from guard member 400 to the proximal end of delivery catheter 304. For example, the pull wire 410 having bifurcated portions 410a, 410b provides a desired 1:1 torque response between the shaft 344a of the delivery catheter 304 and the guard member 400. The elongated portions 410a, 410b of the bifurcated pull wire 410 are radially disposed within the guard member 400, thereby maintaining the torque response between the guard member 400 and the shaft 344a of the delivery catheter 304 as the delivery catheter 304 is rotated. Additionally, the bifurcated pull wire portions 410, 410b are configured to provide column strength to the delivery assembly 300 during advancement of the delivery catheter 304, thereby avoiding and / or minimizing inadvertent proximal movement of the guard member 400 and undesired exposure of the piercing element 350. Additionally, the bifurcated pull wire portions 410a, 410b are configured to resist undesired rotation of the guard member 400 about the delivery catheter distal portion 344, thereby reducing the likelihood that the arcuate marker 425 will provide a misindication of the orientation of the delivery catheter 304 within the vasculature. Upon reaching the target penetration site, the pull wire 410 is configured to move (e.g., pull) the guard member 400 proximally to expose the penetration element 350, as described and illustrated in further detail in FIGS. 4A and 4B.

[0039] 3A-3F, the pull wire 410 having bifurcated portions 410a, 410b can reduce the diameter within the lumen of the delivery assembly compared to having multiple pull wires for the guard member 400. Additionally, because the pull wire 410 can be manufactured by laser cutting and splitting the distal section 411 of a single pull wire, the bifurcated pull wire portions 410a, 410b can reduce manufacturing time and material costs compared to manufacturing two separate pull wires coupled to the guard member 400 that extend between distal and proximal portions of a catheter (not shown).

[0040] The pull wire 410 can be constructed of uncoated stainless steel, coated (e.g., PTFE) stainless steel, or other suitable coated or uncoated materials. A PTFE or other lubricious coating or liner, or the like, on the pull wire 410 and / or within the delivery catheter lumen 322 can increase the lubricity of the wire within the delivery catheter 304, thereby facilitating proximal and distal actuation of the guard 400 to expose and recoat the piercing element 350. The embodiment of the pull wire 410 shown in Figures 3A-3F including sections 412a, 412b have respective rectangular profiles (e.g., flat wire forms), although other pull wire embodiments can include non-rectangular cross-sectional profiles (e.g., circular, crescent). The pull wire 410 having branched portions 410a, 410b including arc-shaped radiopaque markers 425 can minimize the overall profile of the guard member 400 by having less material (e.g., flat branched wires and non-annular markers) and, as a result, minimize the French size of the delivery catheter 304.

[0041] The arc-shaped radiopaque marker 425 may comprise a platinum-iridium 90 / 10 alloy or other suitable material that provides sufficient radiopacity. Additionally, the arc-shaped radiopaque marker 425 may have connection regions 424a, 424b bonded to the respective elongated portions 410a, 410b of the pullwire 410, as shown in FIG. 3E. The two elongated portions 410a, 410b of the pullwire 410 each include a respective distal tip 412a, 412b that is bonded (e.g., attached, welded) to the connection regions 424a, 424b of the arc-shaped radiopaque marker 425. It should be understood that in embodiments in which pull wire 410 has a lubricious coating (e.g., PTFE), distal end tips 412a, 412b do not include a coating, and the uncoated distal end tips 412a, 412b of pull wire 410 allow for welding or other attachment of radiopaque marker 425 at connection regions 424a, 424b.

[0042] As discussed above, the arcuate radiopaque marker 425 (FIGS. 3A, 3B and 3E-F), including a partial cylindrical or semi-cylindrical configuration, minimizes the profile of the guard member 440. Additionally, the arcuate marker 425 is configured to identify the location of the concentrically disposed piercing element 350 (e.g., by tracking the marker location and orientation within the guard member 400) when the arcuate marker 425 and the radiopaque marker 354 of the piercing element 350 are aligned (FIGS. 2B, 4A and 6A). In some embodiments, alignment of the guard marker 425 and the penetrating element marker 354 allows a clinician to identify the location of the penetrating element 350 within the guard member 400 during tracking (e.g., during navigation of the delivery assembly 300 through tortuous anatomy toward a target penetration site), thereby allowing the clinician to monitor or correct inadvertent withdrawal of the guard member 400 and / or the deployment, orientation and / or trajectory of the penetrating element 350. Additionally, the arcuate marker 425 and the penetrating element marker 354 are configured to improve visualization of the delivery catheter 304 under fluoroscopy, as the arcuate marker 425, as opposed to annular markers (not shown), allows the clinician to identify the orientation of the delivery catheter 304 and the penetrating element 350 relative to a target penetration site within the vasculature. 3F, the arcuate marker 425 embedded within the guard member 400 is disposed adjacent the outer surface 470 of the guard member 400 such that the second lumen 415 of the guard member 400 is partially surrounded by the arcuate marker 425. In this embodiment, the arcuate marker 425 is configured to provide structural strength to the guard member 400, which may further avoid and / or minimize undesired tearing of the guard member 400 by the elongate guide member 780 moving within the second lumen 415 of the guard member 400. By improving the structural strength of the guard member 400 including the second lumen 415, embodiments of the delivery catheter 304 may avoid the need for a separate dedicated lumen to receive the elongate guide member 780, as disclosed, for example, in U.S. Pat. No. 10,272,230.Eliminating a lumen in the delivery catheter 304 to accept the elongate guide member may streamline manufacturing steps for the delivery catheter 304 and reduce the overall French profile of the delivery catheter 304 and / or the delivery assembly 300. Additionally, ease of use of the delivery assembly 300 is improved because an operator only needs to thread the elongate guide member 780 through one lumen (e.g., the second lumen 415 of the guard member 400) before advancing the delivery catheter 304 into the patient's body at the venous access site toward a target penetration site within the vasculature.

[0043] As better seen in Figure 3F, which shows a cross-sectional view of Figure 3A, guard member 400 comprises a first lumen 405 configured to receive and / or house piercing element 350 and a second lumen 415 configured to receive and / or house elongate guide member 780. Additionally, guard member 400 is configured to allow for quick exchange with elongate guide member 780, a distal portion of which is coupled to a stent anchor or other temporary anchor element (not shown).

[0044] Returning to FIG. 2B, the guard member 400 is positioned in a delivery configuration relative to the distal portion 344 of the delivery catheter 304, thus covering the piercing element 350 (also shown in FIG. 4A). The piercing element 350 is positioned within the lumen 405 of the guard member 400 and aligned with the radiopaque marker 425 of the guard member 400, with the distal tip of the piercing element overlapping the radiopaque marker 425 under fluoroscopy, as seen, for example, by the piercing element marker 354. The length of the guard member 400 can be about 0.5 inches (1.27 cm) or other suitable dimensions sufficient to cover the piercing element 350 on the distal portion 344 of the delivery catheter 304. The guard member 400 and the delivery catheter 304 including the piercing element 350 are slidable relative to one another. For example, the guard lumen 405 is sized to allow the guard 400 to be retracted proximally past the piercing element 350 and the distal portion 344 of the delivery catheter 304. For example, the inner diameter of the guard lumen 405 may be approximately 0.0385 inches (0.09779 cm).

[0045] As shown in Figures 3A and 3B, the marker 425 and pull wire branches 410a, 410b are embedded or encapsulated within the walls of the guard member 400. The guard member 400 is constructed of a polymeric material such as polyether block amide (Pebax® available from Arkema Group), HTPE, PTFE, nylon, polyurethane, urethane or other polymeric material. Pebax® embodiments of the guard 400 can range in hardness from 27D to 70D (e.g., Pebax® 63D). The wall thickness of the guard 400 can vary from top to bottom.

[0046] As shown in the side view of the guard member 400 in FIG. 3A, the guard member 400 includes a distal portion 404 having a contour / profile similar to one period of a sine function with peaks 444 (e.g., maxima) and valleys 442 (e.g., minima). It should be appreciated that the opposite side view (not shown) of the distal portion 404 of the guard member 400 in FIG. 3A includes a contour / profile having a mirror image one period of a sine function. The contour / profile of the distal portion 404 of the guard member 400 can facilitate access of the delivery catheter 304 to tortuous anatomical structures, where the distal portion 404 of the guard member 400 can first access and advance through a narrow or sharp bend, and then allow the distal portion 344 of the delivery catheter 304 to follow and follow the narrow or sharp bend.

[0047] As shown in perspective (FIGS. 3B and 3C) and top (FIG. 3D) views of guard member 400, guard member 400 includes a tubular structure 401 having an opening 420 at a distal portion 404 of guard member 400. Distal portion 404 of guard member 400 defines opening 420 by having respective peaks 444 of sine functions that are gradually closer to one another and respective valleys 442 of sine functions that are gradually farther apart from one another. The split shape of distal portion 404 of guard member 400 and the convergence of opening 420 transitioning from valleys 442 to peaks 444 of deflecting element 430 (better seen in FIGS. 3C and 3D) can be formed by laser cutting, molding or any other suitable technique of tubular structure 401. The shape of the distal portion 404 of the guard member 400 forms an atraumatic tip 460, further facilitating access to narrow or tortuous vasculature as the clinician guides the delivery assembly towards the target penetration site. For example, the IPS diameter of the internal jugular vein ostium is often smaller than the IPS diameter at the target penetration site of the vessel (e.g., axial level of the jugular tubercle), requiring the operator to trace the delivery catheter 304 through the venous ostium to the target penetration site to access the subarachnoid space. The contour / profile of the distal portion 404 of the guard member 400 allows the distal portion 344 of the delivery catheter 304 to access the vessel from the venous ostium, thereby allowing the remainder of the device to advance distally towards the target penetration site.

[0048] Additionally, the segmented geometry of the distal portion 404 of the guard member 400 includes an arcuate slope 443 between the valley 442 and the peak 444 that forms a deflection element 430 configured to redirect the piercing element 350 away from the elongate guide member 780 (FIG. 4B) toward the piercing site. In some embodiments, the deflection element 430 can be formed with a steeper or less steep slope 443 by varying the height of the peak 444, the depth of the valley 442, and / or the angle "θ" (FIG. 3A) between the deflection element 430 and the longitudinal axis 403 parallel to the lumen 415 (FIGS. 3A-3C) of the guard member 400. The angle "θ" of the slope 443 forming the deflection element 430 can range from about 5 degrees to about 40 degrees, or more. Increasing the angle "θ" of the bevel 443 relative to the longitudinal axis 403 of the guard member 400 increases the distance or separation between the piercing element 350 and the guide member 780, and thus increases the penetration angle of the piercing element 350 relative to the target site. In turn, the increased separation between the piercing element 350 and the guide member 780 improves engagement of the piercing element 350 with the IPS wall 114, allowing the piercing element 350 to better access the SAS. This can be particularly advantageous in vasculature that does not exhibit sufficient curvature around the target penetration site to allow the piercing element 350 to move off-axis from the guide member 780 to access the SAS.

[0049] 4A and 4B show an interface between a piercing element 350 and a guard member 400 according to an embodiment of the present invention. The guard member 400 is placed over the piercing element 350 (FIG. 4A) to prevent inadvertent puncture of the vasculature during tracking of the delivery catheter to the target penetration site. The guard member 400 can translate proximally over the distal portion of the delivery catheter 304 and the piercing element 350 (indicated by arrow I). Additionally, the piercing element 350 can translate distally toward the deflection element 430 of the guard member 400 (indicated by arrow II) to expose the piercing element 350 at the target penetration site (FIGS. 4A and 4B). For example, the clinician can retract the guard member 400 proximally to change its orientation away from the longitudinal axis 403 of the guard member 400 and the elongate guide member 780 such that the piercing element 350 located on the distal portion of the delivery catheter 304 contacts the biasing element 430 / bevel 443 of the guard member 400 (FIG. 4B). In an alternative embodiment of the delivery catheter 304, the clinician can advance the piercing element 350 distally to contact the biasing element 430 / bevel 443 of the guard member 400.

[0050] 5A-5C show another view of the interface between the piercing element 350 and the guard member 400 according to an embodiment of the present invention. For example, FIGS. 5A-5C show the interface between the piercing element 350 and the guard member 400 after the guard member 400 has been retracted proximally to expose the piercing element 350 and / or after the piercing element 350 has advanced distally to contact the deflecting element 430 / bevel 443 of the guard member 400. The split geometry of the distal portion 404 of the guard member 400 having the bevel 443 is configured such that when the piercing element 350 of the delivery catheter is retracted into the guide catheter 320, the deflecting element 430 opens up and collapses around the shaft 344a of the delivery catheter 304. 5A-5C show successive down-the-barrel views in which the delivery catheter 304 is retracted or withdrawn into the guide catheter 320 (e.g., while withdrawing the delivery catheter 304 from the SAS) and the split shape of the deflecting element 430 opens up to allow the penetrating element 350 to at least partially fit within the opening 420, thereby substantially maintaining the diameter of the guide catheter 320. In contrast, in embodiments in which the deflecting element is a rigid feature of the guard member 400 (e.g., does not have a split, respective deflecting element 430 or bevel 443), as the delivery catheter 304 is retracted or withdrawn, the penetrating element 350 is positioned (e.g., pushed) adjacent to the rigid deflecting element (e.g., double barrel) of the guard member, causing the diameter of the guide catheter to unnecessarily expand (not shown). This undesired guide catheter expansion can result in inadvertent dislodging of the shunt 200 from the SAS if the shroud 800 and shunt 200 are also forced into the guide catheter opening by the rigid deflection elements of the guard members prior to shunt deployment.

[0051] 6A-6N show a piercing element 350 according to various embodiments of the present invention. The piercing element 350 includes a sharpened tapered, cannula-like end, a bevel, a pencil, or a Quincke-tip needle, and the like. FIGS. 6A and 6B show the piercing element 350 disposed at the distal portion 344 of the delivery catheter 304. The piercing element 350 further includes a radiopaque marker 354 embedded therein, as best shown in FIG. 6A. FIGS. 6C-6N show an alternative embodiment of the radiopaque marker 354 embedded in the piercing element 350. The embedded marker 354 does not protrude from the outer surface 356 of the piercing element 350 (FIGS. 6A-6N) or the inner surface of the piercing element 350 (not shown), making the inner surface 356 and the outer surface of the piercing element 350 smooth. The radiopaque marker 354 may be embedded in a recess (not shown) in the outer surface 356 of the penetrating element 350 and attached by welding or other suitable technique. The radiopaque marker 354 may comprise a platinum-iridium 90 / 10 alloy or other suitable material that provides sufficient radiopacity. The radiopaque marker 354 is configured to allow the clinician to identify the location of the penetrating element 350 relative to anatomical landmarks (e.g., IPS 102, CP pontine angle cistern) and further allows for alignment with the radiopaque marker 425 of the guard member 400 as shown in FIG. 2B. The increased visibility of the penetrating element 350 via the radiopaque marker 354 may further reduce the risk of deployment of the shunt into the subdural space or venous system and further reduce or avoid the risk of damage to critical structures within the SAS by the penetrating element 350 (e.g., brainstem, vertebral artery, basilar artery, anterior inferior cerebellar artery, cranial nerve VI (abducens nerve)). The radiopaque markers 354 facilitate visualization of the penetrating element 350, thereby preventing inadvertent deployment of the penetrating element 350 through the guard member 400 as the clinician guides the delivery assembly 300 through tortuous anatomical structures toward the target penetration site.

[0052] The radiopaque marker 354 can include an elongated configuration (e.g., longitudinally aligned with the tip of the piercing element 350) as shown in Figures 6A and 6B. Alternatively, the radiopaque marker 354 can include a set of at least two elongated markers arranged approximately parallel to one another (e.g., offset relative to the tip of the piercing element 350) as shown in Figure 6C. Figures 6D and 6E show a single elongated marker 354, while Figures 6D and 6E are side views of Figure 6C with two sets of markers. Figures 6F-6H show another alternative embodiment of the radiopaque marker 354 of the piercing element 350, where the radiopaque marker 354 includes an elongated marker 354a and an annular marker 354b. The elongated marker 354a can be longitudinally aligned with the tip of the piercing element 350, as in FIG. 6A, while the annular marker 354b is disposed at the proximal portion 357 of the piercing element 350. The annular marker 354b includes a side portion 354b' (e.g., a square, a rectangle, or other suitable shape), as shown in FIGS. 6F-6H. FIGS. 6I-6K show yet another embodiment of the radiopaque marker 354 of the piercing element 350, where the radiopaque marker 354 includes a "T" shape. The "T" shape of the marker 354 is disposed in a curved semi-annular configuration with the base of the "T" longitudinally aligned with the tip of the piercing element 350 and the apex of the "T" curved at the proximal portion 357 of the piercing element 350, as shown in FIGS. 6I-6K. 6L-6N show another alternative embodiment of the radiopaque marker 354 of the piercing element 350, having an elongated marker 354a similar to that of FIG. 6F and two side markers 354c, 354d disposed on the proximal portion 357 of the piercing element 350.

[0053] The embodiments of the radiopaque markers 354 shown in Figures 6A-6N are configured to provide visual feedback regarding the orientation of the penetrating element 350 within the vasculature, which can facilitate visualization and prevent the penetrating element 350 from being inadvertently deployed through the guard member 400. Various embodiments of the radiopaque markers 354 facilitate visualization of the penetrating element 350 around the target penetration site and visualization of the trajectory of the penetrating element 350 into the SAS. For example, marker 354b and portion 354b' (Figures 6F-6H), the apex "T" shape of marker 354 (Figures 6I-6K), and markers 354c, 354d (Figures 6L-6N) allow the clinician to identify the location of the penetrating element 350 relative to the radiopaque markers 425 of the guard member 400, while allowing the clinician to identify the orientation of the penetrating element 350 within the guard member 400 and within the vasculature.

[0054] 7A-7D and 8A-8D show an implant (e.g., a shunt) and a shroud according to an embodiment of the present invention. FIG. 7A shows a combination of a shunt 200 and a shroud 800, FIGS. 7B-7D show an interface between a distal portion of the shroud 800 and a distal portion of the shunt 200, and FIGS. 8A-8D show an interface between a proximal portion of the shroud 800 and a proximal portion of the shroud 800 and a shroud proximal retention feature 850. The shroud 800 is at least partially disposed over the shunt 200 and configured to be movable relative to the shunt (FIGS. 7B and 7C). The shroud 800 is configured to minimize friction on the shunt 200 and / or stretching of the shunt to avoid or reduce the risk of shunt 200 failure (e.g., tearing of the polymeric shunt body, removal of heparin or other coatings on the shunt body, damage to the shunt valve, etc.). Additionally, the disclosed embodiments of the shroud 800 provide a smoother and more controlled release of the shroud 200 because the shroud 800 does not capture a stretched "neck" (e.g., a temporary reduction in outer diameter due to stretching and elongation of the shunt body) as compared to shroud embodiments that encapsulate a stretched and elongated shunt 200 (e.g., the shunt delivery shuttle embodiments disclosed in U.S. Patent Application Publication No. 20200030588A1).

[0055] The shroud 800 includes a tubular body 820 having a proximal portion 810, a distal portion 830, and a lumen 833 extending therebetween, as shown in Figures 7A-7D. The shroud 800 further includes a proximal marker 860 and a distal marker 862, as shown in Figure 7A. The proximal marker 860 and the distal marker 862 are constructed of tantalum or any other radiopaque material suitable for visualizing the shroud 800 under fluoroscopy. In particular, the proximal and distal markers 860, 862 are configured to allow visualization of the shroud 800 relative to the shunt 200 during advancement, deployment, and / or delivery of the shroud 200 at the target site. The shroud distal marker 862 includes an annular configuration, while the shroud proximal marker 860 includes an annular tapered configuration (FIG. 7A) for gradually guiding the shroud 800 (e.g., as the shroud 800 moves out from within the piercing element 350 to advance the shunt 200 to the target site). In alternative embodiments, the shroud proximal and distal markers 860, 862 can include any suitable configuration.

[0056] 7A, the delivery wire 308 is shown proximate to the proximal marker 860 of the shroud 800. The delivery wire 308 is configured to direct, advance and / or retract the shroud 800 and shunt 200 through the first lumen 305 of the delivery catheter 304 (not shown). The delivery wire 308 includes dimensions (e.g., a diameter of about 0.010 inches (0.254 mm) to 0.018 inches (0.4572 mm)) suitable for guiding the shroud 800 and shunt 200 through the first lumen 305 of the delivery catheter 304 and into the SAS. As known in the art, the delivery wire 308 includes a tapered configuration to provide a gradual transition from a stiff portion (i.e., proximal section) to a flexible portion (i.e., distal section) such that the delivery wire 308 transmits translational and rotational forces for directing, advancing, and / or retracting the shroud 800 and shunt 200, including when the distal portion 344 of the delivery catheter 304 is disposed within tortuous anatomy. In some embodiments, the delivery wire 308 is further tapered along the length of the shroud 800 to allow smooth actuation of the shunt 200. An embodiment of the delivery wire may include a stop 310 (e.g., a bushing as shown in FIG. 15D) to prevent an operator from advancing the delivery wire too far distally and losing the proximal end of the delivery wire inside the delivery device twillborst during the procedure.

[0057] The tubular body 820 of the shroud 800 comprises superelastic Nitinol (or any other suitable superelastic alloy or material) having an intermittent helical cut pattern (FIGS. 7A-7D) or any other suitable cut pattern configured to provide flexibility and kink resistance to the shroud 800 during tracking through the first lumen 305. In some embodiments, the shroud 800 includes at least one axial spine along the length of the tubular body 820. For example, the cut pattern of the tubular body 820 includes an intermittent helical cut that leaves a continuous uncut portion of the tubular body 820 forming an axial spine (not shown). In embodiments of the shroud 800 having at least one axial spine, the axial spine provides column strength to the shroud 800, thereby aiding the shroud 800 in moving the shunt 200 through the first lumen 305 of the delivery catheter 304. Additionally, the axial spine of the shroud 800 avoids or minimizes spring forces on the tubular body 820, such as when the shroud 800 transitions from disposed within the delivery catheter 304 to deployed from the penetrating element 350. This advantageously prevents the distal portion 830 of the shroud 800 and / or the shunt 200 from bouncing or "popping out" (excessive and inadvertent distal movement of the shroud 200) at the target deployment site, for example, as the shroud 800 and shunt 200 advance through the penetrating element 350 and are released away from the penetrating element. Additionally, the cut pattern of the shroud 800 having at least one axial spine is still configured to provide flexibility and kink resistance while the shroud 800 tracks within the first lumen 305 of the delivery catheter 304. The disclosed inventive embodiments are improved over the shunt delivery shuttle embodiments disclosed in U.S. Patent Application Publication No. 20200030588A1. Because embodiments of the shroud 800 resist potential kinking and crimping of the tubular body and lumen on the shunt body that may prevent the shroud from being fully released from the shroud, the shroud can prevent situations in which the shunt is not released from the delivery assembly.

[0058] The shroud 800 is configured to slide distally over the shunt 200 to engage the shunt (FIGS. 7B and 7C) and move and advance the shunt 200 through the first lumen 305 and penetrating element 350 of the delivery catheter 304 toward the target implantation site. Additionally, the shroud 800 is configured to engage (e.g., contact, abut, grasp) the proximal portion 202 of the shunt 200 (FIGS. 8C-8E) to assist in the controlled positioning and advancement (e.g., movement, translation, pushing) of the shunt 200 through the delivery assembly 300. FIG. 7B shows the shroud distal portion 830 sliding over the elongated body 203 of the shunt 200, and FIG. 7C shows the shroud 800 positioned over the shunt 200 toward the anchoring mechanism 229 (e.g., malecot) of the shunt. 7B, 10D and 10E, the shunt body 203 comprises an OD that is smaller than the outer diameter of the shroud 800 such that the shunt 200 is slidably disposed within the lumen 833 of the shroud 800, except that the outer diameter "OD" of the anchoring mechanism 229 of the shunt 200 is substantially the same OD as the OD of the shroud 800. Additionally, the anchoring mechanism 229 of the shunt 200 comprises an annular edge 204' configured to contact / abut an annular edge 862' of the marker 862 of the shroud 800 (FIGS. 7B-7D, 10D and 10E). During engagement of the shroud 800 and the shunt 200, the annular edge 862' of the marker 862 of the shroud 800 contacts / abuts the annular edge 204' of the anchoring mechanism 229 at the distal portion 204 of the shunt 200 while the shroud 800 is advanced over the shunt 200 (FIGS. 7B and 10E). As can be better seen in FIGS. 7C and 7D, when the annular edge 862' of the marker 862 is in contact with the annular edge 204' of the anchoring mechanism 229 of the shunt 200, the OD of the engagement shroud 800 and the shunt 200 are substantially the same, e.g., the outer diameter is flush, nearly flush, or the same OD between the distal portion 830 (e.g., the distal marker 862) of the shroud and the distal anchoring mechanism 229 of the shunt 200.Thus, when the distal portion 830 of the shroud 800 engages the distal portion 204 of the shunt 200 with the distal anchor mechanism 229, it is configured to move, advance and / or push the shunt 200 through the first lumen 305 and penetrating element 350 of the delivery catheter 304 for deployment and delivery at the target site.

[0059] 8A-8F illustrate operation of an embodiment of a shroud 800 in conjunction with the proximal portion 202 of the shunt 200. The proximal portion 810 of the shroud 800 includes a proximal retention feature 850 (FIGS. 7A, 8B-8F, 9A and 9B). FIGS. 9A-9E illustrate alternative embodiments of the proximal retention feature 850 of the shroud 800 in a relaxed / expanded configuration (FIGS. 9A, 9C and 9D) and a collapsed / contracted configuration (FIGS. 9B and 9E). The proximal retention feature 850 is configured to hold, grip and / or restrain the proximal portion 202 of the shunt 200 to aid in advancement of the shunt 200, for example, through the delivery catheter lumen 305 to a target site. The proximal retaining feature 850 is configured to slide over the proximal portion 202 of the shunt 200, which is configured to be disposed within the retaining feature 850 (FIG. 8B) such that the retaining feature 850 grips the proximal portion 202 of the shunt 200 by assuming a collapsed / contracted configuration (FIGS. 8D, 8E, 9B, and 9E) (e.g., when the proximal portion 202 of the shunt 200 and the shroud retaining feature 850 are constrained within the delivery catheter first lumen 305). The proximal retaining feature 850 includes a plurality of elongated members 801 extending between two annular members 802, each of the plurality of elongated members 801 including a protrusion 803 disposed approximately centrally thereon, as better seen in FIGS. 8B and 9A-C.

[0060] 8E shows a detailed internal view of the delivery catheter 304 with the restraining retention feature 850 of the shroud 800 engaging the shunt proximal portion 202 within the delivery catheter lumen 305. The proximal portion 202 of the shunt 200 is securely restrained by the elongate member which is forced towards the shunt by the restrained protrusions 803 of the retention feature 850. FIG. 8F shows a detailed view of the shunt proximal portion 202 and proximal retention feature 850 emerging from the delivery catheter 304 with the protrusions 803 of the retention feature 850 no longer restraining the shunt proximal portion 202 upon deployment from the delivery catheter penetrating element 350.

[0061] 9C illustrates an alternative embodiment of FIGS. 9A and 9B, where the projections 803′ of FIG. 9C comprise a smaller radius, thickness and / or surface area (further illustrated in FIGS. 8E and 8F) than the projections 803 of FIGS. 9A and 9B. Variations in the radius, thickness and / or surface of the projections 803 of the retention features 850 of the shroud 800 depend on the desired retention force (e.g., compressive force acting on the shunt or other device) required for the shunt 200 disposed within the first lumen 305 of the delivery catheter 304. It should be understood that the larger the radius, thickness and / or surface of the projections 803, the greater the compressive force acting on the shunt 200 when the shunt 200 is disposed within the shroud lumen 833 and the shroud 800 is disposed within the first lumen 305 of the delivery catheter 304 (FIG. 8D).

[0062] In further alternative embodiments, one or more protrusions 803 may be disposed along any suitable portion of each elongate member 801 of the proximal retaining feature 850. The protrusions 803 of the proximal retaining feature 850 are configured to gradually guide the shroud 800 as it moves through the first lumen 305 of the delivery catheter and advances the shroud 200 through the penetrating element 350 to the target site. Additionally, the proximal retaining feature 850 including multiple elongate members 801 has less material (e.g., having slots 805 between the elongate members 801 in FIG. 8B ) as opposed to a cylindrical retaining feature (not shown) having a constant surface area. The proximal retaining feature 850 with less material or surface area is configured to minimize friction between the shroud 800 and the penetrating element 350, which may facilitate advancement of the shroud 800 through the delivery catheter lumen 305 when the catheter is positioned within a tortuous anatomy.

[0063] Shroud 800 may be constructed of titanium, tantalum, stainless steel, nitinol, or other superelastic alloys or materials. In some embodiments, shroud 800 may be manufactured by cutting, electropolishing, and / or welding appropriate materials and components to manufacture shroud 800. For example, retaining features 850 may be manufactured by laser cutting a tubular member or by joining multiple elongated members 801 to two annular members 802.

[0064] 9D and 9E show cross-sectional views of the proximal retention feature 850 of FIGS. 8F and 8E, respectively. As shown in FIG. 9D, the projections 803 of the retention feature 850 of the shroud 800 are in a relaxed, expanded, or unconstrained configuration, and the lumen 833 of the shroud 800 is not obstructed by the projections 803. In the unconstrained configuration, the projections 803 do not grip or compress the shunt proximal portion and the shunt, and the shunt is free to move within the shroud lumen 833. The unconstrained configuration facilitates loading the shunt into the shroud 800 and deployment of the shunt at the target location, for example, during packaging and sterilization of the device (FIG. 8F). As shown in FIG. 9D, the projections 803 of the retention feature 850 of the shroud 800 are in a collapsed, contracted, or constrained configuration. When the protrusions 803 are restrained (e.g., by advancing the shroud 800 and shunt 200 distally through the delivery device lumen 26 and into the delivery catheter lumen 305), the protrusions 803 are biased into the shroud lumen 833. When restrained, the protrusions 803 grip or compress the shunt proximal portion 202 (FIGS. 8D and 8E), preferably proximal to the shunt valve 209. This occurs as the shunt 200 and shroud 800 advance through the delivery device lumen 26 and the handle 10 and into the first lumen 305 of the delivery catheter 304. As shown by the arrows in FIG. 9E, the protrusions 803 are biased to be restrained radially inward when the proximal retaining feature 850 is restrained within the delivery catheter lumen 805. The configuration of the retaining feature 850 constrained within the delivery catheter lumen 805 maintains positive engagement of the shroud 800 with the shunt 200 (Figures 8D and 8E), thereby allowing the delivery wire 803 to advance and retract the shunt 200 and shroud 800 within the delivery catheter lumen 305.As the shroud 800 and shunt 200 advance distally through the delivery catheter lumen 305 via the delivery wire 308 and out of the piercing element 350 for shunt deployment, the retention feature protrusions 803 are no longer constrained by the inner diameter of the delivery catheter lumen 305 and the retention feature elongate members 801 expand radially to disengage the shunt proximal portion 202 and the retention feature 850 (FIG. 8F). FIGS. 10A-10E show perspective, detail and cross-sectional views of a shunt 200 (e.g., a shunt) according to an embodiment of the disclosed invention. The shunt 200 comprises a proximal portion 202, a body portion 203, a distal portion 204 and a lumen 207 extending therebetween, as shown in FIG. 10A. As shown in the detail view of FIG. 10B, the proximal portion 202 of the shunt 200 comprises a valve 209 and a radiopaque marker 240. The valve 209 is configured to be in fluid communication with the shunt lumen 207. In some embodiments, the valve 209 is a one-way valve including one or more slits 241. The marker 240 comprises a cylindrical band embedded in the proximal portion 202 of the shunt 200 (FIGS. 8C and 10B). To improve engagement with the proximal retention feature 850 and minimize impact on the valve 209 and CSF lumen 207 of the shunt 200, the proximal tip of the shunt 200 (e.g., the proximal portion 202 of the shunt adjacent the most proximal edge of the shunt lumen 207 shown in FIG. 10B) can be a solid or substantially solid piece of polymeric material of the shunt body 203 and the proximal marker 240. In an alternative embodiment, the marker 240 can be swaged onto the distal portion 204 of the shunt 200. The marker 240 can be constructed of any suitable radiopaque material and include a suitable surface area to aid in visualization of the shunt 200 under fluoroscopy and avoid or minimize risk to the patient during access to the CP pontine angle cistern.

[0065] The shunt 200 (e.g., the proximal 202 and body 203 portions) includes one or more elastomeric polymers suitable for implant applications, including, but not limited to, silicone, polyurethane, polycarbonate urethane, thermoplastic polyurethane, aromatic or aliphatic polycarbonate thermoplastic polyurethane, silicone / polyurethane blends (e.g., thermoplastic silicone polycarbonate polyurethane with 20% silicone copolymer), or polyurethane silicone blends (e.g., polyurethane silicone copolymer). The materials of the shunt 200 are selected to advantageously resist thrombus formation, particularly in the proximal portion 202 of the shunt 200. Optionally, the shunt 200 includes an anti-thrombus coating to prevent thrombus formation, including, but not limited to, heparin-based or phosphorylcholine-based anti-thrombus coatings.

[0066] The distal portion 204 of the shunt 200 includes an anchoring mechanism 229 (e.g., a malecot) having a compressed configuration (FIG. 15C) for guiding through a delivery catheter 304 and an expanded configuration (FIGS. 7A-7D, 10A, 10C-10E) for anchoring the shunt 200 at a target site in a patient. The anchoring mechanism 229 is constructed of titanium, stainless steel, nitinol or other superelastic alloys. The anchoring mechanism 229 includes a proximal retention element or collar 230, a distal radiopaque marker 228, and a plurality of elongated deformable elements 229a (e.g., arms) disposed therebetween (FIGS. 10A, 10C-10E). The proximal retention element or collar 230 includes the distal anchoring mechanism 229, the shunt distal portion 204, and the annular edge 204′, as described above in connection with FIGS. 7B, 10D, and 10E. The proximal collar 230 and the distal marker 228 are comprised of a suitable radiopaque material and may include an annular configuration. The deformable element 229a is disposed radially outward in the expanded configuration of the anchoring mechanism 229. When the shunt 200 is deployed out of the delivery catheter 304, the anchoring mechanism 229 transitions (e.g., self-expands) from a compressed configuration within the delivery catheter 304 to its expanded or deployed configuration. During deployment, a clinician can observe under fluoroscopy that the proximal collar 230 and the distal marker 228 approach each other and can confirm that the anchoring mechanism 229 has properly transitioned to its expanded or deployed configuration.

[0067] 11A-11C are perspective and down-the-barrel views of an elongated guide member 780, an anchor 700, and a proximal marker 245, according to an embodiment of the disclosed invention. The elongated guide member 780 can have a flat, rectangular, or other non-circular cross-sectional profile, as shown, for example, in FIGS. 2A and 11B. As shown in the detailed view of FIG. 11B, the elongated guide member 780 is coupled (e.g., directly or indirectly attached, secured, or joined) to a proximal portion 740 of the anchor 700. The anchor 700 can be constructed of a shape-memory, self-expanding, and biocompatible material, such as Nitinol®, or other superelastic alloys, stainless steel, or cobalt chrome, or combinations thereof, and includes a stent-like configuration. In some embodiments, the anchor 700 can include a material that is compatible with magnetic resonance imaging and has sufficient radiopacity to use known imaging techniques. Alternatively, the anchor 700 can be constructed of magnesium, zinc, or other bioabsorbable or dissolvable components. The anchor 700 further comprises a radially collapsed or delivery configuration (not shown) and a radially expanded or deployed configuration (FIG. 11A). In the deployed configuration, the anchor 700 is configured to radially expand and anchor itself within the IPS or CS, allowing tracking and advancement of the guard member 400 slidably disposed about the elongated guide member 780 (FIG. 4B).

[0068] The proximal portion 740 of the anchor 700 includes a proximal marker 245, as shown in Figures 11A and 11B. Figures 12A and 12B are perspective and down-the-barrel views of the proximal marker 245. The proximal marker 245 includes an outer surface 245a including peaks and valleys, and an inner surface 245b defining an opening 245b' and a lumen 245b'' (Figures 11A-12B), with the outer surface 245a and the inner surface 245b forming a contour 245c of the proximal marker 245, as better seen in Figure 12B. The proximal marker outer surface 245a, inner surface 245b, and contour 245c are configured to fit snugly within the proximal portion 740 of the anchor 700, as shown in Figures 11A and 11B. The proximal marker 245 is configured to provide and maximize tensile strength when coupled to the anchor 700 and the elongate guide member 780. The proximal marker 245 is constructed of tantalum or any other suitable radiopaque material. In some embodiments, the proximal marker 245 is manufactured by an electrode wire cutting mechanism "EDM" that is programmed to form the contour 245c of the proximal marker 245. The EDM manufacturing process produces a proximal marker 245 that has a larger volume compared to prior art markers, which can result in a smaller gap 246 between the proximal marker 245 and the proximal portion 740 of the anchor 700, as shown in FIG. 11B.

[0069] FIG. 13 shows a cross-sectional view of a handle 10 for the delivery catheter 304 of FIG. 1 according to an embodiment of the disclosed invention. The handle 10 is configured to be coupled to or integrated into the delivery catheter 304 in place of the luer assembly 17 of FIG. 1. As shown in FIG. 13, the handle 10 includes a luer fitting 12, a delivery lumen flush port 14, a tether lumen flush port 16, a tether actuation mechanism 18, a strain relief mechanism 19, and a proximal portion 324 of the delivery catheter 304. The delivery lumen flush port 14 is in fluid communication with the first lumen 305 of the delivery catheter 304. The tether lumen flush port 16 is an optional feature of the handle 10, and the tether lumen flush port 16 is in fluid communication with the delivery catheter lumen 322 that receives the pull wire 410 for actuating the guard member 400. In some embodiments, the flush ports 14, 16 are one-way lumen flush ports. During clinical use, flush port 14 and flush port 16 can be connected to pressurized saline bags to maintain fluid flow through the respective delivery catheter lumens 305, 322 to prevent backflow of blood into such delivery catheter lumens and the formation of air bubbles therein. A tether actuation mechanism 18 is integrated into the handle 10 for actuating the guard member 400. In some embodiments, the tether actuation mechanism 18 is separate from the handle (not shown).

[0070] 14A-14D show perspective and cross-sectional views of an alternative embodiment of the handle of FIG. 13 in accordance with an embodiment of the disclosed invention. As shown in FIG. 14A-14D, handle 10' includes the same features as handle 10 (i.e., luer fitting 12, delivery lumen flush port 14, tether retraction mechanism 18, strain relief mechanism 19, and proximal portion 324 of delivery catheter 304), except that handle 10' does not include a separate optional tether lumen flush port. Tether actuation mechanism 18 is configured to rotate, as shown by arrow 18a in FIG. 14B, which can release mechanism 18 from handle 10' to allow translational movement 18b, as shown in FIG. 14C. Additionally, the tether actuation mechanism 18 can be configured to be pulled down as shown by arrow 18b in FIG. 14C, thereby transmitting a force to the pull wire 410 to actuate the guard member 400 in a proximal direction to expose the piercing element 350 from the guard member 400. It should be understood that the tether actuation mechanism 18 of FIG. 13 can be configured to be actuated in the manner disclosed and described in FIGS. 14B-14D. Additionally, the tether actuation mechanism 18 of FIG. 13 can be configured to be actuated in the opposite direction to that disclosed and described in FIGS. 14B-14D, thereby transmitting a force to the pull wire 410 to actuate the guard member 400 in a distal direction to cover the piercing element 350 with the guard member 400. FIG. 14D shows a cross-sectional view of the handle 10' of FIGS. 14A-14C. As shown in FIG. 14D, the tether retraction mechanism 18 is coupled to the pull wire 410. In some embodiments, the proximal end of the pull wire 410 is fixedly coupled to the tether retraction mechanism 18 .

[0071] 15A-15C show perspective and detailed views of a delivery device 20 according to an embodiment of the disclosed invention. FIGs. 15D-15G show perspective and detailed views of a delivery device 20' according to an embodiment of the disclosed invention. The delivery device 20 / 20' is configured to deliver the shunt 200 and shroud 800 to either the handle 10 or 10' (FIGS. 16A and 16B). As shown in FIG. 16A, the delivery device 20 is coupled to the handle 10, and as shown in FIG. 16B, the delivery device 20' is coupled to the handle 10'. It should be understood that either delivery device 20 / 20' is configured to be coupled to either handle 10 / 10'.

[0072] Each transfer device 20 / 20' includes a Twi Borst adapter 21, a Luer fitting 22, a passive seal 23, a housing 24, and a stopcock 25, as shown in Figures 15A, 15B, and 15D. The housing 24 includes a lumen 26 extending therethrough, and the lumen 26 and the passive seal lumen 23' are configured to receive the shunt 200 and the shroud 800. As shown in Figures 15D and 15E, the transfer device 20' includes the same features as the transfer device 20, and further includes a support member 27 disposed within the housing 24. The support member 27 is configured to provide column support to the housing 24, the lumen 26, and / or the shroud 800 for transfer of the shunt 200 and the shroud 800 via the lumen 26 and the passive seal lumen 23' to either the handle 10 or 10'. The support member 27 may comprise a tube, elongated member, etc., of metal, polymer, or any other suitable material. In the embodiment of Fig. 15D and Fig. 15E, the support member 27 comprises a first support member 27a and a second support member 27b, and Fig. 15G shows a cross-sectional view of the first support member 27a, the passive seal 23, and the second support member 27b according to the embodiment of the transfer device of Fig. 15D. The support member 27a has an inner diameter (ID) between 0.0665-0.685 mm, and the support member 27b has an ID between 1.30-1.42 mm. It should be understood that the ID of each support member 27a / 27b may be tapered or constant within the above range (e.g., the ID of the support member 27a is 0.675 mm, and the ID of the support member 27b is 1.37 mm).

[0073] As shown in Figures 15D-15F, the shunt 200 and shroud 800 are disposed within the lumen 26 of the housing 24, with the proximal portion 202 of the shunt 200 and the proximal portion 810 of the shroud 800 including the retaining feature 850 being disposed within the first support member 27a of the delivery device lumen 26 (detailed view of Figure 15E), and the distal portion 204 of the shunt 200 and the anchor mechanism 229 being disposed within the second support member 27b and passive seal lumen 23' of the delivery device lumen 26 (detailed view of Figure 15F). In some embodiments, the ID of the support member 27a tapers (e.g., tapers radially inward in the distal direction) toward the passive seal 23' of the housing 24 (shown as taper 27a' in FIG. 15E) such that the retention features 850 of the shroud 800 (shown in a relaxed / expanded configuration in FIG. 15E) assume a collapsed / contracted configuration (FIGS. 9B and 9E) as the shroud is advanced distally through the taper of the support member 27a. For example, the ID of the lumen of the tubular support member 27a decreases distally along the length of the distal portion such that the shroud retention features 850 compress to secure or grip the proximal portion 202 of the shunt 200 as the shroud 800 and shunt 200 are advanced distally through the lumen of the tubular support member 27a. The support member 27a is configured to collapse, restrain and / or hold down the protrusions 803 of the retention feature 850 as the shroud 800 and shunt 200 are moved / pushed distally or longitudinally through the lumen 26 of the housing 24, thereby securing the proximal portion 202 of the shunt 200 within the retention feature 850 of the shroud 800. The passive seal lumen 23' and ID of the support member 27b are also configured to maintain the collapsed / contracted configuration of the retention feature 850, thereby engaging and securing the proximal portion 202 of the shunt 200 during transport of the shroud 800 through the delivery device lumen 26 and into the handle 10 / 10'.During clinical use, the Tuy Borst adapter 21 is configured to open to allow the delivery wire 308, the shroud 800, and the shunt 200 to move distally through the transfer device lumen 26 and into the handle 10 / 10' of the delivery catheter 304. Prior to clinical use (e.g., during shipping of the device), the Tuy Borst adapter 21 is closed around the delivery wire 308 to prevent inadvertent displacement or dislodgement of the shunt 200 and the shroud 800 from the transfer device 20 / 20'. Additionally, the Tuy Borst adapter 21 is configured to prevent backflow of fluid during clinical use of the device. The luer fitting 22 of the transfer device 20 is configured to engage and couple with the luer fitting 12 of the handle 10 / 10' as shown in FIGS. 16A and 16B. The stopcock 25 is a three-way valve configured to stop the flow of fluid when the stopcock 25 is placed in a closed position. The housing 24 and delivery device lumen 26 are configured to dispose the shroud 800 and shunt 200 therein, as shown in Figures 15C and 15D, and detailed views of the housing 24 are shown in Figures 15C, 15E, and 15F. When the shroud 800 and shunt 200 are disposed within the delivery device lumen 26, the shroud 800 is disposed over the shunt 200. The anchoring mechanism 229 of the shunt 200 is in a compressed configuration within the housing 24, as shown in the detailed views of Figures 15C, 15F, and the passive seal 23 of the housing 24 holds the anchoring mechanism 229 in the compressed configuration (Figures 15C, 15F) for handling, preparation of the delivery assembly 300, and flushing of the shunt 200.

[0074] With the shunt 200 disposed within the shroud 800, the shunt 200 and shroud 800 are loaded into the delivery device 20 / 20'. As shown in Figures 15C and 15F, the distal portion 204 of the shunt 200 and the distal portion 830 of the shroud 800 are partially disposed within a passive seal lumen 23' within the fluid path of the delivery device lumen 26. The passive seal 23 is configured to seal around a portion of the distal anchor mechanism 229 and the distal portion 204 of the shunt 200 (Figure 15F) to facilitate flushing of fluid through the shunt lumen 207 and flow of fluid from the reservoir 50 (described below in Figures 17A and 17B) while confirming patency of the shunt valve 209 during preparation for implantation of the shunt 200. The passive seal lumen 23' provides an interference fit with the distal anchor mechanism 229 and the distal portion 204 of the shunt 200 such that fluid entering the delivery device lumen 26 via the Luer fitting 22 is directed into the shunt lumen 207, minimizing fluid flow around the distal anchor mechanism 229 and the outer surface of the shunt body 203.

[0075] The clinician can complete a patency test 500 when the shroud 800 and shunt 200 are placed within the delivery device 20 / 20' (FIG. 18) and then verify the outflow from the stopcock 25 (e.g., prior to implantation of the shunt 200), as further described in FIGS. 17A and 17B.

[0076] Following the valve patency test 500, the clinician couples the delivery device 20 to the handle 10 / 10' (FIGS. 16A and 16B) and uses the delivery wire 308 to move (i.e., push) the shroud 800 and shunt 200 distally from the passive seal 23 into the lumen 26 of the delivery device 20 / 20' (FIGS. 15B-15G, 16A and 16B), through the lumen of the delivery device, into the handle 10 / 10', and into the lumen 305 of the delivery catheter 304. As previously described, the shroud 800 moves the shunt 200 through the handle 10 / 10' and into the delivery catheter lumen 305 with the shroud distal radiopaque marker 862 pushing against the shunt engagement region 244 and the proximal retention feature 850 pushing against the shunt proximal portion 202. The delivery device lumen 26 is in fluid communication with the handle 10 / 10'. The clinician can use the markers on the shroud 800 and / or the delivery wire 308 to assist in positioning the shroud 800 and shunt 200 within the handle 10 / 10' so that the delivery assembly 300 is suitable for a medical procedure. The clinician can continue to advance the shroud 800 and shunt 200 via the delivery wire 308 into the distal portion of the first lumen 305 of the delivery catheter. One or more markings on the proximal portion of the delivery wire 308 are configured to indicate when the delivery wire 308 has been sufficiently advanced such that the shroud 200 and shroud 800 are advanced into the distal portion of the lumen 305, thereby providing additional column strength and kink resistance to the distal portion 344 of the delivery catheter 304 during the implantation procedure.

[0077] FIG. 17A shows a perspective view of a reservoir assembly 50 according to an embodiment of the disclosed invention. FIG. 17B shows a top view of the reservoir assembly 50 and a perspective view of a transfer device 20 / 20' according to an embodiment of the disclosed invention. As shown in FIGS. 17A and 17B, the reservoir assembly 50 includes a three-way stopcock 52 having a plurality of luer fittings 53, 54 and 55, the stopcock 52 being secured to a base 51. The base 51 includes a hinge or swivel mechanism coupled to the stopcock 52, and the reservoir assembly 50 is packaged with a fluid column 64 lying parallel to the die card surface of FIG. 17. When the clinician or technician is ready for the shunt 200 for clinical use, the reservoir assembly 90 is rotated 90 degrees upward from the die card until the base 51 provides a positive lock to hold the reservoir assembly 50 and fluid column 64 upright, as shown in FIG. 17A. Positive locking is achieved by an interference fit of a molded hinge component (not shown) in the base 51 .

[0078] As shown in FIG. 17B, the reservoir assembly 50 is in fluid communication with the luer 22 and lumen 26 of the transfer device 20 via the flushing line 56 of the reservoir assembly 50. The luer fitting 53 of the reservoir assembly 50 is coupled to a syringe 63, which allows for flushing of fluid into the flushing line 56 connected to the transfer device lumen 26 of the transfer device 20 via the stopcock 52 and the luer fitting 55. The stopcock 52 can be open to allow fluid flow from the syringe 63 for flushing of the flushing line 56 connected to the transfer device 20. Flushing of fluid from the reservoir assembly 50 into the transfer device 20 / 20′ is configured to flush the fluid through the shunt lumen 207 via the passive seal 23, thereby removing air bubbles (which may impede, reduce, or increase backflow of fluid through the valve 209 (not shown) of the shunt 200). Additionally, the luer fitting 54 of the reservoir assembly 50 is coupled to a fluid column 64. The stopcock 52 can be opened to fill the column 64 with fluid (e.g., saline, heparinized saline, sterile water) and the stopcock 52 can be opened to allow fluid to flow from the fluid column 64 through the flushing line 56 and into the transfer device 20. With the fluid column 64 filled and the stopcock 52 open to the transfer device 20 / 20', fluid is allowed to flow from the column 64 through the flushing line 56 and into the transfer device 20 / 20' and the transfer device lumen 26. The passive seal 23 of the housing 24 of the transfer device 20 / 20' holds the shunt anchor mechanism 229 in a compressed configuration and provides a fluid seal around the shunt 200 disposed in the lumen 26 of the transfer device 20 / 20' (FIGS. 15C, 15F and 15G). The passive seal 23 directs the flow of fluid received from the flushing line 56 through the lumen 26 into the distal portion of the shunt lumen 207 , out the shunt valve 209 , through the transfer device lumen 26 and out the stopcock 25 of the transfer device 20 .Fluid column 64 can be filled to a known height to provide a desired or known amount of fluid pressure to valve 209 (via flushing line 56, transfer device lumen 26 and passive seal lumen 23').

[0079] FIG 18 illustrates a patency test 500 for verifying patency of a shunt 200 according to an embodiment of the present invention. The patency test 500 verifies that the shunt 200 and shunt valve 209 provide a therapeutic flow rate (e.g., 5 mL / hr or greater) of CSF from the SAS to the venous system at a target differential pressure range between the SAS and the venous system following a shunt deployment procedure. The transfer device 20 / 20' (FIGS. 15A-15G, 16A and 16B) and reservoir assembly 50 (FIGS. 17A and 17B) are configured for use in the methods, operations and / or steps described in the patency test 500 of FIG 18. The patency test 500 includes a step 510 of connecting the reservoir assembly 50 to the transfer device 20 / 20' via the flushing line 56; a step 520 of flushing the flushing line 56 and the shunt 200 disposed within the transfer device 20 with saline or heparinized saline via the syringe 63 (e.g., at least once, or preferably more than once); a step 530 of filling the fluid column 64 with saline to a height that correlates to the expected pressure difference between the SAS and the venous system; a step 540 of opening the stopcock 52 to allow fluid to flow from the fluid column 64 to the flushing line 56, into the lumen 26 of the transfer device 20, and through the shunt 200 (e.g., into the CSF lumen 207 and out of the valve 209); and a step 550 of observing fluid flow from the three-way stopcock 25 of the transfer device 20 / 20' to confirm that the lumen 207 and valve 209 of the shunt 200 are patent. Optionally, there is a step 560 of verifying that the fluid level in the fluid column 64 has dropped a preset distance (e.g., 1 cm) in a preset period (e.g., 5 minutes) while fluid flows from the fluid column 64 into the flushing line 56 and the transfer device 20 / 20' and out of the shunt 200.A preset fluid drop in fluid column 64 from a specified fluid height in fluid column 64 over a specified period of time can be correlated to known fluid flow rates for a range of fluid pressures applied through the shunt lumen 207 and valve 209, thereby providing an indication of expected CSF flow rate and therapeutic performance through the shunt 200 during clinical use of the device.

[0080] For example, the use of the delivery device 20 / 20′ and reservoir assembly 50, as described in patency test 500, eliminates the prior art need for the clinician to advance or proximally withdraw the shunt 200 through the piercing element 350 into the delivery catheter 304, avoiding the risk of the piercing element 350 scraping, tearing, or damaging the shunt 200, including the shunt lumen 207 and shunt valve 209, during loading. Additionally, the use of the delivery device 20 / 20′ and reservoir assembly 50 eliminates the prior art need for the clinician to directly handle the shunt 200 during clinical use and preparation of the device for the implantation procedure. Direct handling of the shunt 200 or conventional shunt devices implanted via an open surgical procedure compromises the sterility of the device and increases the risk of introducing contaminants into the shunt 200 prior to the deployment procedure, causing infection in the patient. Additionally, the transfer device 20 / 20' eliminates the need to directly handle the shunt 200 throughout all of the preparation for clinical use steps such as flushing, patency testing 500, and loading of the delivery catheter.

[0081] It should further be appreciated that the lumen 26 of the transfer device 20 / 20′ and the first lumen 305 of the delivery catheter 304 should have substantially similar diameters, eliminating the need for a shroud 800 to accommodate stretching of the shunt 200 and localized contraction of the outer diameter of the shunt 200 during loading of the shunt 200 into the delivery catheter 304. Stretching the shunt 200 can potentially damage the polymeric shunt body and / or biocompatible coatings on the outer surface of the shunt 200 and / or valve 209. Stretching of the shunt 200, as was necessary in prior art systems, would require complex shroud designs to maintain control over the shunt 200 within the first lumen 305 of the delivery catheter and would significantly increase friction between the shunt 200 and the first lumen 305 during the implantation procedure. In addition to complex shroud designs, prior art systems relied on complex devices to flush the shunt 200, stretch the shunt 200, and load the shunt 200 into the first lumen 305 of the delivery catheter through the penetrating element 350 of the delivery catheter, as disclosed, for example, in U.S. Patent Application Publication No. 20210228846. Furthermore, the need to stretch the shunt 200 in the prior art required the clinician to overcome resistance between the shunt 200 and the first lumen 305 of the delivery catheter 304 while advancing the shunt 200 through the first lumen 305 and out of the penetrating element 305 during the shunt deployment procedure. Such resistance-overcoming actions can reduce the important tactile feedback received by the clinician during the shunt deployment procedure. The embodiments of the delivery catheter 304, shroud 800 and transport device 20 disclosed herein overcome the drawbacks caused by shunt stretching, reduce resistance to shunt advancement, and provide an overall smoother and more controlled deployment of the shunt 200.

[0082] An embodiment of a delivery catheter 304 is disclosed for guiding and deploying the shunt 200. The delivery catheter 304 may also be used in other procedures requiring access to a patient's SAS and / or deployment of a device. For example, an embodiment of the delivery catheter 304 may be used to access the SAS and deliver a therapeutic agent from the first lumen 305 of the delivery catheter. Alternatively, a microcatheter may be guided through the first lumen 305 and the piercing element 350 of the delivery catheter to a predetermined location or region within the SAS and the therapeutic agent may be delivered through the microcatheter into the SAS. Non-limiting examples of therapeutic agents that can be delivered to the SAS with embodiments of the delivery catheter 304 include antisense RNA or antisense oligonucleotides, antibodies, antibiotics, antivasospastic agents, biosimilars, chemotherapeutic agents, GABA receptor agonists, therapeutic agents intended to treat neurodegenerative diseases (e.g., Alzheimer's disease, Parkinson's disease, Huntington's disease, prion diseases, motor neuron diseases, spinocerebellar ataxias, and spinal muscular atrophy), therapeutic agents intended to treat trigeminal neuralgia, therapeutic agents intended to treat pontine gliomas, compositions comprising tissue plasminogen activator, and any other composition intended to have a therapeutic effect on all or a portion of the central nervous system.

[0083] While particular embodiments have been disclosed and described herein, they are not intended to limit the present invention, and it will be apparent to one skilled in the art that various changes, substitutions and modifications (e.g., various part sizes, combinations of parts) can be made without departing from the scope of the disclosed invention, which is defined solely by the following claims and equivalents thereof. Accordingly, the specification and drawings are to be regarded in an illustrative and not a restrictive sense. The various embodiments disclosed and described herein are intended to cover alternatives, modifications and equivalents of the disclosed invention, which may fall within the scope of the appended claims.

Claims

1. 1. A delivery system for deploying an implant, comprising: a delivery catheter including a first delivery catheter lumen extending from an open distal end of the delivery catheter into a handle coupled to a proximal end portion of the delivery catheter; a tissue-piercing element disposed at the open distal end of the delivery catheter and extending distally from the open distal end of the delivery catheter; a guard member including a proximal portion disposed over and movable relative to each tissue-piercing element and the distal end of the delivery catheter, the guard member defining a guard member lumen configured to receive and cover the tissue-piercing element, the guard member lumen defining a longitudinal axis of the guard member; a proximal portion of the guard member transitioning to a split-opening distal portion adjacent a distal opening of the guard member lumen, the split-opening distal portion including a contour configured to engage the tissue-piercing element and deflect the tissue-piercing element at an angle relative to the longitudinal axis of the guard member when the guard member moves proximally relative to the tissue-piercing element; a split-opening distal portion of the guard member comprising arcuately angled portions on either side of the contour, the angled portions having respective surfaces configured to engage and deflect the tissue-piercing element.

2. 10. The delivery system of claim 1, a profile of the split-open distal portion of the guard member configured to allow each of the opposing angled portions to open and collapse around the tissue-penetrating element when the respective guard member and delivery catheter are retracted into the guide catheter.

3. 3. The delivery system of claim 1 or 2, The delivery system, further comprising a pull wire coupled to the guard member and configured to move the guard member proximally relative to the tissue-piercing element.

4. 4. The delivery system of claim 3, A delivery system, wherein a distal portion of the pull wire bifurcates into respective first and second pull wire members.

5. 5. The delivery system of claim 4, and a guard member lumen extending from the distal end of the guard member lumen to a distal end of the guard member lumen, the guard member having a distal opening and a distal arc-shaped radiopaque marker embedded therein, the first and second pull wire members being attached to the respective arc-shaped radiopaque markers.

6. 6. The delivery system of claim 5, 10. The delivery system of claim 9, wherein the guard member lumens include a first guard member lumen, the guard member further including a second guard member lumen spanning between a proximal portion and a distal portion of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member travels, and the second guard member lumen is partially surrounded by an arcuate marker.

7. 4. The delivery system of claim 3, the delivery catheter further comprises a second delivery catheter lumen, the pull wire being disposed within the second delivery catheter lumen; The handle is a flush port in fluid communication with the first catheter lumen; a tether actuation mechanism, wherein a proximal end of the pull wire is coupled to the tether actuation mechanism, the tether actuation mechanism configured to be pulled relative to the handle, thereby moving the guard member relative to the tissue penetrating element, thereby exposing the tissue penetrating element.

8. 4. The delivery system of claim 3, A delivery system, wherein a distal portion of the pull wire is embedded within the guard member.

9. 10. The delivery system of claim 1, 10. The delivery system of claim 9, further comprising an arc-shaped radiopaque marker embedded within the guard member adjacent a distal opening of the guard member lumen.

10. 10. The delivery system of claim 9, 10. The delivery system of claim 9, wherein the guard member lumens include a first guard member lumen, the guard member further including a second guard member lumen spanning between a proximal portion and a distal portion of the guard member, the second guard member lumen configured to receive an elongate guide member over which the guard member travels, and the second guard member lumen is partially surrounded by an arcuate marker.

11. 10. The delivery system of claim 9, further comprising an elongated radiopaque marker spine embedded in said tissue-penetrating element; the marker spines are aligned substantially parallel to a longitudinal axis of the tissue-piercing element; 1. A delivery system comprising: an arc-shaped radiopaque marker embedded in the guard member and a radiopaque marker spine embedded in the tissue-penetrating element configured to indicate the position, orientation, and trajectory of the tissue-penetrating element when the tissue-penetrating element is positioned within the guard member lumen.

12. A catheter, a first catheter lumen extending from the open distal end of the catheter into a handle coupled to a proximal end portion of the catheter; a tissue-piercing element disposed at the open distal end of the catheter and extending distally therefrom; a guard member disposed over each tissue-piercing element and the distal end of the catheter, the guard member including a proximal portion movable relative to the tissue-piercing elements and the distal end of the catheter, the guard member defining a guard member lumen configured to receive and cover the tissue-piercing elements, the guard member lumen defining a longitudinal axis of the guard member; a proximal portion of the guard member transitioning to a split-open distal portion adjacent a distal opening of the guard member lumen, the split-open distal portion including a contour configured to engage the tissue-piercing element and deflect the tissue-piercing element at an angle relative to a longitudinal axis of the guard member as the guard member moves proximally relative to the tissue-piercing element.

13. The catheter of claim 12, a split-opening distal portion of the guard member comprising arcuately angled portions on either side of the contour, the angled portions having respective surfaces configured to engage and deflect the tissue-piercing element.

14. The catheter of claim 13, a contour of the split-open distal portion of the guard member configured to allow each of the opposing angled portions to open and fold around the tissue-penetrating element when the guard member and catheter are retracted into the guide catheter.

15. The catheter according to any one of claims 12 to 14, The catheter further comprising a pull wire coupled to the guard member and configured to move the guard member proximally relative to the tissue-piercing element.

16. 16. The catheter of claim 15, A catheter wherein a distal portion of the pull wire bifurcates into respective first and second pull wire members.

17. 17. The catheter of claim 16, a first pull wire member and a second pull wire member attached to the guard member lumen, the first pull wire member being attached to the first radiopaque marker and the second pull wire member being attached to the second radiopaque marker.

18. 18. The catheter of claim 17, a catheter, the catheter comprising: a first guard member lumen, the guard member further comprising a second guard member lumen spanning between a proximal portion and a distal portion of the guard member; the second guard member lumen configured to receive an elongate guide member over which the guard member travels; and the second guard member lumen being partially surrounded by an arcuate marker.

19. 16. The catheter of claim 15, the catheter further comprises a second catheter lumen, the pull wire being disposed within the second delivery catheter lumen; The handle is a flush port in fluid communication with the first catheter lumen; a tether actuation mechanism, wherein a proximal end of the pull wire is coupled to the tether actuation mechanism, the tether actuation mechanism configured to be pulled relative to the handle, thereby moving the guard member relative to the tissue-penetrating element, thereby exposing the tissue-penetrating element.

20. 17. The catheter of claim 16, A catheter, wherein a distal portion of the pull wire is embedded within the guard member.

21. The catheter of claim 12, The catheter further comprises an arc-shaped radiopaque marker embedded within the guard member adjacent a distal opening of the guard member lumen.

22. 22. The catheter of claim 21, a catheter, the catheter comprising: a first guard member lumen, the guard member further comprising a second guard member lumen spanning between a proximal portion and a distal portion of the guard member; the second guard member lumen configured to receive an elongate guide member over which the guard member travels; and the second guard member lumen being partially surrounded by an arcuate marker.

23. 23. The catheter of claim 22, further comprising an elongated radiopaque marker spine embedded in said tissue-penetrating element; the marker spines are aligned substantially parallel to a longitudinal axis of the tissue-piercing element; When the tissue-penetrating element is positioned within the guard member lumen, an arc-shaped radiopaque marker embedded in the guard member and a radiopaque marker spine embedded in the tissue-penetrating element are configured to indicate the position, orientation, and trajectory of the tissue-penetrating element.

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