US20230172614A1

US20230172614A1 - Aneurysm treatment with pushable ball segment

Info

Publication number: US20230172614A1
Application number: US18/101,630
Authority: US
Inventors: Ruijiao XU; Lacey GOROCHOW
Original assignee: DePuy Synthes Products Inc
Current assignee: DePuy Synthes Products Inc
Priority date: 2019-05-21
Filing date: 2023-01-26
Publication date: 2023-06-08
Also published as: US11672542B2; US20200367906A1

Abstract

The present invention provides a braided implant with a retractable dual proximal layer and methods for administering the braided implant to treat aneurysms. The implant can include a tubular braid that can be set into a predetermined shape, compressed for delivery through a microcatheter, and implanted in at least one implanted position that is based on the predetermined shape and the geometry of the aneurysm in which the braid is implanted. The implant can also have a retractable ball segment at the proximal end of the device made of the same braid that can be heat treated into an ellipsoid shape. The retractable ball segment can be movable from a position outside the aneurysm to a position at least partially enclosed within the implant to increase or decrease the height of the implant relative to the aneurysm or better conform the implant to the neck of the aneurysm.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent application Ser. No. 16/865,165 filed May 1, 2020, which is a continuation-in-part of U.S. patent application Ser. No. 16/853,135 filed Apr. 20, 2020, issued as U.S. Pat. No. 11,497,504 on Nov. 15, 2022, which is a continuation-in-part of U.S. patent application Ser. No. 16/418,199 filed May 21, 2019, issued as 10,653,4725 on May 19, 2020.
U.S. patent application Ser. No. 16/865,165 filed May 1, 2020, is also a continuation-in-part of U.S. patent application Ser. No. 16/748,877 filed Jan. 22, 2020.
The contents of all of which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention generally relates to medical instruments, and more particularly, to embolic implants for aneurysm therapy.

BACKGROUND

Aneurysms can be complicated and difficult to treat. For example, treatment access may be limited or unavailable when an aneurysm is located proximate critical tissues. Such factors are of particular concern with cranial aneurysms due to the brain tissue surrounding cranial vessels and the corresponding limited treatment access.
Prior solutions have included endovascular treatment access whereby an internal volume of the aneurysm sac is removed or excluded from arterial blood pressure and flow. In this respect, because the interior walls of the aneurysm may continue being subjected to flow of blood and related pressure, aneurysm rupture remains possible.
Alternative to endovascular or other surgical approaches can include occlusive devices. Such devices have typically incorporated multiple embolic coils that are delivered to the vasculature using microcatheter delivery systems. For example, when treating cranial aneurysms, a delivery catheter with embolic coils is typically first inserted into non-cranial vasculature through a femoral artery in the hip or groin area. Thereafter, the catheter is guided to a location of interest within the cranium. The sac of the aneurysm can then be filled with the embolic material to create a thrombotic mass that protects the arterial walls from blood flow and related pressure. However, such occlusive devices do have certain shortcomings, including mass effect, which can cause compression on the brain and its nerves.
For example, embolic coils delivered to the neck of the aneurysm can potentially have the adverse effect of impeding the flow of blood in the adjoining blood vessel, particularly if the entrance is overpacked. Conversely, if the entrance is insufficiently packed, blood flow can persist into the aneurysm. Treating certain aneurysm morphology (e.g. wide neck, bifurcation, etc.) can require ancillary devices such a stents or balloons to support the coil mass and obtain the desired packing density. Once implanted, the coils cannot easily be retracted or repositioned. Furthermore, embolic coils do not always effectively treat aneurysms as aneurysms treated with multiple coils often recanalize or compact because of poor coiling, lack of coverage across the aneurysm neck, blood flow, or large aneurysm size.
Another particular type of occlusive approach endeavors to deliver and treat the entrance or “neck” of the aneurysm. In such “neck” approaches, by minimizing blood flow across the neck, a cessation of flow into the aneurysm may be achieved. It is understood that the neck plane is an imaginary surface where the inner most layer of the parent wall would be but for the aneurysm. However, neck-occlusive approaches, such as implanting a flow impeding device in the parent vessel, are not without drawbacks. Such an approach may impede blood flow into peripheral blood vessels while blocking the aneurysm neck in the parent vessel. Impeding flow to the peripheral blood vessel can unintentionally lead to severe damage if the openings of the vessels are blocked.
Alternatives to embolic coils are being explored, such as tubular braided implants. Tubular braided implants have the potential to easily, accurately, and safely treat an aneurysm or other arterio-venous malformation in a parent vessel without blocking flow into perforator vessels communicating with the parent vessel. Compared to embolic coils, however, tubular braided implants are a newer technology, and there is therefore capacity for improved geometries, configurations, delivery systems, etc. for the tubular braided implants. For instance, delivery of tubular braided implants can require unique delivery systems to prevent the braid from inverting or abrading when pushed through a microcatheter, and some simple delivery systems that push embolic coils through microcatheters from their proximal end may not be effective to deliver tubular braids.
There is therefore a need for improved methods, devices, and systems for implants for aneurysm treatment.

SUMMARY

It is an object of the present invention to provide systems, devices, and methods to meet the above-stated needs. Generally, it is an object of the present invention to provide a braided implant with a retractable dual proximal layer. The implant can secure within an aneurysm sac and occlude at least a majority of the aneurysm's neck. The implant can include a tubular braid that can be set into a predetermined shape, compressed for delivery through a microcatheter, and implanted in at least one implanted position that is based on the predetermined shape and the geometry of the aneurysm in which the braid is implanted. The implant can also have a retractable ball segment at the proximal end of the device made of the same braid that can be heat treated into an ellipsoid shape. The retractable ball segment can be movable from a position outside the aneurysm to a position at least partially enclosed within the implant to increase or decrease the height of the implant relative to the aneurysm or better conform the implant to the neck of the aneurysm.
In some examples presented herein, the dual layer can be shaped by expanding it radially, and the dual layer can be pressed distally into a first portion of the tubular braid already within the aneurysm. By pressing the dual layer distally into the first portion of the tubular braid, the first portion of the tubular braid can be moved towards the distal portion of an aneurysm wall so that the implant can partially or completely occlude an aneurysm neck. Pushing the dual layer into the first portion of the braid can help conform the implant to the shape of the aneurysm and resist compaction. The dual layer when expanded radially and pressed into the first portion of the braid also can provide additional coverage at the neck of the aneurysm to increase thrombosis. In some examples, the dual layer can also be placed within the aneurysm sac with only a detachment point external to the sac.
In some examples, the tubular braid can include memory shape material that can be heat set to a predetermined shape, can be deformed for delivery through a catheter, and can self-expand to an implanted shape that is based on the predetermined shape and confined by the anatomy of the aneurysm in which it is implanted.
In some examples the tubular braid can be shaped to a delivery shape that is extended to a single layer of tubular braid having a compressed circumference/diameter sized to be delivered through the microcatheter.
In some examples, before the implant is released from the delivery system, the implant can be partially or fully retracted into the microcatheter and repositioned.
An example method for forming an occlusive device to treat an aneurysm can include one or more of the following steps presented in no particular order, and the method can include additional steps not included here. An implant with a tubular braid, an open end, and a pinched end can be selected. The tubular braid can be shaped to a predetermined shape. Shaping the tubular braid to a predetermined shape can also include further steps. These steps can include inverting the tubular braid to form a distal inversion. The tubular braid can also be inverted to form a proximal inversion by moving the open end over at least a portion of the braid. A first segment of the tubular braid extending between the open end and the proximal inversion can be shaped. A second segment of the tubular braid extending between the proximal inversion and the distal inversion can be shaped. The open end can be positioned to encircle the second segment. A third segment extending from the distal inversion to the proximal inversion can be shaped. The second segment can be positioned to surround the third segment. A fourth segment of the tubular braid extending from the third segment radially outward from a central axis to cross the proximal inversion can be shaped and can fold and converge at the pinched end. The fourth segment can be positioned near the neck of an aneurysm.
An example method for treating an aneurysm can include one or more of the following steps presented in no particular order, and the method can include additional steps not included here. A first portion of a tubular braided implant, which can have a tubular braid, an open end, and a pinched end, can be positioned within a sac of the aneurysm such that the first portion circumferentially apposes walls within the sac. The first portion can have one or more inversions. A second portion of the tubular braided implant can be expanded radially to occlude a majority of a neck of the aneurysm. The second portion can be pressed distally into the first portion. The first portion of the tubular braided implant can be moved toward a distal portion of the aneurysm wall as a result of pressing the second portion distally into the first portion.
In some examples, expanding the second portion of the tubular braided implant can include positioning a fold in the second segment to define a substantially circular perimeter of the second portion and compressing the second portion along a central axis of the tubular braided implant such that the second portion can have a substantially circular shape having an area and two layers of braid over a majority of the area of the substantially circular shape.
In some examples, positioning the first portion of the tubular braided implant can further include shaping the tubular braided implant to form a columnar post encircling a central axis of the tubular braided implant and extending a majority of a height of the first portion. In another example, positioning the first portion of the tubular braided implant can further involve positioning a proximal inversion near the neck of the aneurysm and positioning a distal inversion approximate the distal portion of the aneurysm wall. In another example, positioning the first portion of the tubular braided implant can further involve positioning the open end of the tubular braided implant to circumferentially appose the aneurysm wall, shaping a first segment of the tubular braid extending between the open end and the proximal inversion to appose at least a portion of a wall of the aneurysm within the aneurysm's sac, and shaping a second segment of the tubular braid such that the first segment provides an outwardly radial force in a plane defining a boundary between the aneurysm and blood vessel branches, the force sufficient to appose the first segment to walls of the aneurysm.
In some examples, pressing the second portion distally into the first portion can further involve pressing the second portion of the tubular braided implant against the proximal inversion in the first portion of the tubular braided implant.
Another example implant can be formed in a series of steps and heat treated to be set to a predetermined shape. The tubular braid can include two inversions, a pinched end, and an open end. The tubular braid can also include four segments. The first segment can extend from the open end of the tubular braid to a proximal inversion. The second segment can be at least partially encircled by the open end and can extend from the proximal inversion to a distal inversion.
The third segment can then be surrounded by the second segment and extend from the distal inversion to a ball segment. The ball segment can extend from a proximal end of the third segment and be shaped radially outward from a central axis of the tubular braid to form a substantially ellipsoid shape and converge at the pinched end. This form can be heat treated with a mold to set the implant into the predetermined shape, and once the mold is removed, the predetermined shape is formed.
This example implant can then be implanted within an aneurysm. The aneurysm can have a range of different heights. When in the implanted shape, the braid can have an outer layer corresponding to the first segment of the predetermined shape and positioned to contact an aneurysm wall. The braid can also have a proximal inversion corresponding to the proximal inversion of the predetermined shape positioned near an aneurysm neck, and a sack corresponding to the second segment of the predetermined shape that apposes the outer layer. A distal inversion can correspond to the distal inversion of the predetermined shape, and a third segment can correspond to the third segment in the predetermined shape. The first, second, and third segments can make up a first portion of the braid. The braid can also have a ball segment corresponding to the ball segment of the predetermined shape and extending from the third segment radially outward from a central axis to form a substantially ellipsoid shape and converge at the pinched end. The ball segment can be pressed distally into the first portion of the tubular braid.
When implanted, the ball segment can be positioned external to the aneurysm sac, extending across the aneurysm neck. The ball segment can occlude at least a portion of the aneurysm neck. By pressing the ball segment into the first portion of the tubular braid, the first portion of the tubular braid can be moved towards the distal portion of an aneurysm wall. Pushing the ball segment into the first portion of the braid can appose the proximal inversion to provide a radially outward force against the proximal inversion so that the tubular braid contacts a wall of the aneurysm approximate a neck of the aneurysm.
In an alternative example, pushing the ball segment distally into the first portion of the tubular braid can push the third segment distally into the aneurysm towards a distal portion of the aneurysm wall. This movement of the third segment can be independent of distal movement of the outer layer and/or sack. This can extend the height of the implant to better conform to the height of the aneurysm. At least a portion of the ball segment can be enclosed by the sack. At least a portion of the ball segment can be positioned external to the sack.
An example method for treating an aneurysm can include positioning a first portion of a tubular braided implant, the tubular braided implant having a tubular braid, an open end, and a pinched end, to circumferentially appose the aneurysm's walls. The first portion can include one or more inversions, including a distal inversion approximate a distal portion of the aneurysm wall. This example method can further include expanding a second portion of the tubular braided implant in connection with the first portion of the tubular braided implant radially to occlude a majority of the neck of the aneurysm. Then, the second portion can be pressed distally into the first portion to provide a radial force against the first portion towards the aneurysm wall approximate the neck of the aneurysm in a plane defining a boundary between the aneurysm and blood vessel branches. Lastly, the distal inversion can be moved toward a distal portion of the aneurysm wall as a result of pressing the second portion distally into the first portion.
Another example method for forming an occlusive device to treat an aneurysm can include the step of inverting a tubular braid comprising an open end and a pinched end to form a distal inversion. The method can further involve inverting the tubular braid to form a proximal inversion by moving the open end over at least a portion of the braid. The method can also include shaping a first segment of the tubular braid extending between the open end and the proximal inversion. The example method can further include shaping a second segment of the tubular braid extending between the proximal inversion and the distal inversion. The method can also include positioning the open end to encircle the second segment. The method can further involve shaping a third segment extending from the distal inversion to the pinched end. Then, the method can include positioning the second segment to surround the third segment. The method can further include shaping a ball segment of the tubular braid extending from the third segment radially outward from a central axis to form a substantially ellipsoid and converge at the pinched end. The method can also involve applying a mold to the ball segment of the tubular braid and treating the ball segment with heat to conform the ball segment to a formed shape, the ball segment movable along a central axis of the tubular braid.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and further aspects of this invention are further discussed with reference to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating principles of the invention. The figures depict one or more implementations of the inventive devices, by way of example only, not by way of limitation.

FIG. 1A is an illustration of an example implant having a tubular braid in a predetermined shape according to aspects of the present invention;

FIG. 1B is an illustration of the example implant with the tubular braid in a first implanted shape according to aspects of the present invention;

FIGS. 2A through 2I are illustrations of an implant having a tubular braid that expands to an implanted shape similar to as illustrated in FIG. 1B as the tubular braid exits a microcatheter according to aspects of the present inventions;

FIGS. 3A through 3B are flow diagrams for a method of forming an occlusive device to treat an aneurysm;

FIGS. 4A through 4B are flow diagrams for a method for treating an aneurysm;

FIGS. 5A through 5B are illustrations of an example implant being formed into a predetermined shape according to aspects of the present invention;

FIGS. 6A through 6C are illustrations of an implant having a tubular braid in an implanted shape according to aspects of the present invention;

FIG. 7 is a flow diagram for a method of treating an aneurysm; and

FIG. 8 is a flow diagram for a method of forming an occlusive device to treat an aneurysm.

DETAILED DESCRIPTION

Examples presented herein generally include a braided implant that can secure within an aneurysm sac and occlude a majority of the aneurysm's neck. The implant can include a tubular braid that can be set into a predetermined shape, compressed for delivery through a microcatheter, and implanted in at least one implanted position that is based on the predetermined shape and the geometry of the aneurysm in which the braid is implanted. The implant can include a single layer of braid (e.g. a braid that can be extended to form a single layer tube) heat treated into multiple layers with retractable dual layer at the proximal end of the tubular braid. When compressed, the implant can be sufficiently short to mitigate friction forces produced when the implant is delivered unsheathed through the microcatheter.
A first portion of the tubular braid can be positioned in an aneurysm, after which the retractable dual layer can be deployed from the microcatheter and pushed onto the first portion of the tubular braid. This configuration provides three layers of braid at the neck of the aneurysm. The dual layer can potentially cover any gap between the first portion of implanted tubular braid and the aneurysm neck, and can potentially increase metal coverage, decrease porosity of the implant, and increase stasis and blood flow diversion at the neck of the aneurysm to promote the sealing and healing of the aneurysm compared a similarly shaped braided implant lacking the dual layer. The entire implant can be retractable until a desired position is achieved.
FIGS. 1A and 1B are illustrations of an example braided implant 100 that can have a predetermined shape as shown in FIG. 1A and a distinct implanted shape as illustrated in FIG. 1B. The implant 100 can treat a range of aneurysm sizes. The implant 100 can include a tubular braid 110 having an open end 114 and a pinched end 112. The implant 100 can include a connection and detachment feature 150 (referred to equivalently as “connection feature” and “detachment feature” herein) attached to the braid 110 at the pinched end 112. The pinched end 112 can include a marker band and/or soldered point with visibility, and/or the connection feature 150 can include radiopaque material. The tubular braid 110 can be formed in the predetermined shape (FIG. 1A), collapsed for delivery through a microcatheter, attached to a delivery system at connection feature 150, and implanted in an implanted shape such as the one shown in FIG. 1B.
Referring to FIG. 1A, when in the predetermined shape, the tubular braid 110 can include two inversions 122, 124, a pinched end 112, and an open end 114. The tubular braid 110 can include four segments, 142, 144, 146, and 152. The first segment 142 can extend from the open end 114 of the tubular braid 110 to a proximal inversion 122. The second segment 144 can be encircled by the open end 114 and extend from the proximal inversion 122 to a distal inversion 124. The third segment 146 can be surrounded by the second segment 144 and extend from the distal inversion 124 to the proximal inversion 122. The first segment 142, second segment 144, and third segment 146 can form the first portion of the tubular braid 110. The fourth segment 152 can extend from the third segment 146 radially outward from a central axis to cross the proximal inversion 122, fold, and converge at the pinched end 112. The fourth segment 152 can be partially encircled by the proximal inversion 122.
When in the predetermined shape, the tubular braid 110 can be substantially radially symmetrical about a central vertical axis. The detachment feature 150 is illustrated in FIG. 1A as a flat key that can be used with a mechanical delivery implant system (not pictured). The tubular braid 110 can be formed into the predetermined shape by first inverting the braid outwardly to separate the third segment 146 from the second segment 144 with a distal inversion 124. Then, the second segment 144 can be shaped over a form to produce the substantially “S” shaped profile illustrated in FIG. 1A. Next, the braid 110 can be inverted outwardly again to separate the second segment 144 from the first segment 142 with a proximal inversion 122. Finally, the fourth segment 152 can be shaped by expanding the fourth segment 152 radially. The fourth segment 152 can be pressed distally into the first portion of the tubular braid 110. It can also be advantageous to minimize a neck opening 126 defined by the lower extension of the “S” shape of second segment 144 to maximize occlusion of an aneurysm neck when the implant 100 is implanted.
The tubular braid 110 can include memory shape material that can be heat set to a predetermined shape, can be deformed for delivery through a catheter, and can self-expand to an implanted shape that is based on the predetermined shape and confined by the anatomy of the aneurysm in which it is implanted. When the tubular braid 110 is in the predetermined shape as depicted in FIG. 1A, the fourth segment 152 can comprise a diameter D1 greater than or approximately equal to a maximum diameter D2 of the first segment 142. Alternatively, when the tubular braid 110 is in the predetermined shape as depicted in FIG. 1A, the fourth segment 152 can comprise a diameter D1 lesser than a maximum diameter D2 of the first segment 142. When the tubular braid 110 is in the predetermined shape (FIG. 1A), the second segment 144 can form a sack, and at least a portion of the third segment 146 can positioned within the sack and at least a portion of the fourth segment 152 can be positioned external to the sack. As illustrated (FIG. 1B), when implanted, the fourth segment 152 can be positioned external to the aneurysm sac, extending across the aneurysm neck 16. Preferably, the fourth segment 152 can appose vasculature walls surrounding the aneurysm neck 16 when implanted. Alternatively, the shaped fourth segment 152 can also be placed within the aneurysm sac. The detachment feature 150 can be implanted centrally in the aneurysm neck 16. The detachment feature 150 can be positioned external to the sac 12.
The tubular braid 110 in the implanted shape (FIG. 1B) can be radially or vertically compressed or extended compared to the predetermined shape. As illustrated in FIG. 1B, when in the implanted shape, the braid 110 can have an outer layer 142 a corresponding to the first segment 142 of the predetermined shape and positioned to contact an aneurysm wall 14 of the aneurysm 10, a proximal inversion 122 a corresponding to the proximal inversion 122 of the predetermined shape and positioned to be placed approximate a neck 16 of the aneurysm 10, and a sack 144 a corresponding to the second segment 144 of the predetermined shape and positioned to appose a portion of the aneurysm wall 14 of the aneurysm 10 and apposing the outer layer 142 a. A distal inversion 124 a can correspond to the distal inversion 124 of the predetermined shape, a third segment 146 a can correspond to the third segment 146 in the predetermined shape. The braid 110 can also have a fourth segment 152 a corresponding to the fourth segment 152 of the predetermined shape and extending from the third segment 146 a radially outward from a central axis to cross the proximal inversion 122 a, fold, and converge at the pinched end 112. As described in FIG. 1A, the fourth segment 152 a can be pressed distally into the first portion of the tubular braid 110.
By pressing the fourth segment 152 a distally into the first portion of the tubular braid 110, the first portion 142 a, 144 a, 146 a of the tubular braid 110 can be moved towards the distal portion of an aneurysm wall 15 to occlude a portion of the neck 16 of the aneurysm 10. Pushing the fourth segment 152 a into the first portion of the braid 110 can help conform the implant 100 to the shape of the aneurysm 10 and resist compaction. The fourth segment 152 a when expanded radially and pressed into the first portion of the braid 110 also can provide additional coverage at the neck 16 of the aneurysm 10 to increase thrombosis and seal the aneurysm 10. When the fourth segment 152 a is pressed into the first portion of the braid 110, three layers of braid are present at the neck of the aneurysm. The fourth segment 152 a can cover spatial gaps between the first portion of implanted tubular braid 110 and the aneurysm neck 16, and can potentially increase metal coverage, decrease porosity of the implant 100, and increase stasis and blood flow diversion at the neck 16 of the aneurysm 10 to promote the sealing and thrombosis of the aneurysm 10. The fourth segment 152 a can be shaped to occlude the majority of an aneurysm neck 16 when the device 100 is implanted. The fourth segment 152 a can be shaped to completely occlude an aneurysm neck 16 when the device 100 is implanted.
When the tubular braid 110 is in the implanted shape (FIG. 1B), the fourth segment 152 a can comprise a diameter D1 greater than or approximately equal to a maximum diameter D2 of the first segment 142 a. Alternatively, when the tubular braid 110 is in the implanted shape (FIG. 1B), the fourth segment 152 a can comprise a diameter D1 lesser than a maximum diameter D2 of the first segment 142 a. When the tubular braid 110 is in the implanted shape (FIG. 1B), the second segment 144 a can form a sack, and at least a portion of the third segment 146 a can be positioned within the sack and at least a portion of the fourth segment 152 a can be positioned external to the sack. The shaped fourth segment 152 a can also be placed within the aneurysm sac 12 with only the detachment point 150 external to the sac 12.
FIGS. 2A through 2I are illustrations of an example implant 100 having a braid 110 expanding to an implanted shape that is based on a predetermined shape and the anatomy of the aneurysm and nearby blood vessel as the braid 110 exits a microcatheter 600. The implant 100 has a predetermined shape similar to the shape illustrated in FIG. 1A. As illustrated in FIG. 2A, the braid 110 can be shaped to a delivery shape that is extended to a single layer of tubular braid having a compressed circumference/diameter sized to be delivered through the microcatheter 600 and a length L. As will be appreciated and understood by a person of ordinary skill in the art, the length L of a specific braid 110 can be tailored based on the size and shape of the aneurysm being treated. The length L can be approximately 1 inch in length.
During delivery through the microcatheter 600, the detachment feature 150 can be attached to a delivery system at a proximal end of the implant 100, the pinched end 112 can be positioned near the proximal end of the implant 100, and the open end 114 can define the distal end of the implant 100. Collapsing the braid 110 to a single layer tube can result in a braid 110 that has a sufficiently small diameter and a sufficiently short length L to mitigate effects of friction force on the braid 110 when it is delivered through the microcatheter, allowing the braid 110 to be delivered unsheathed in some applications
As illustrated in FIG. 2B, the implant 100 can be delivered to an aneurysm 10 through the microcatheter 600. The open end 114 can be positioned to exit the microcatheter 600 before any other portion of the braid 110 exits the microcatheter. The open end 114 can expand within the aneurysm sac 12 as it exits the microcatheter 600. The illustrated aneurysm 10 is positioned at a bifurcation including a stem blood vessel 700 and two branch vessels 702, and the microcatheter 600 is illustrated being delivered through the stem blood vessel 700. It is contemplated that the implant could be delivered to an aneurysm on a sidewall of a blood vessel through a curved microcatheter, and such a procedure is intended to be embraced by the scope of the present disclosure. As illustrated in FIG. 2C, the distal portion of the braid 110 can continue to expand radially within the aneurysm sac 12 as it exits the microcatheter 600. As the braid 110 is further pushed distally from the microcatheter 600, the braid 110 can appose the aneurysm wall 14 and conform approximate the aneurysm neck 16. The aneurysm 10 being treated can have a diameter that is less than the outer diameter of the tubular braid 110 in the predetermined shape so that the braid 110 tends to expand outwardly, providing a force against the aneurysm wall 14 and sealing approximate the perimeter of the aneurysm neck 16.
As illustrated in FIG. 2D, the braid 110 can form the proximal inversion 122 a defining the first segment 142 a as the braid 110 is further pushed out of the microcatheter 600. The proximal inversion 122 a can be positioned approximate the aneurysm neck 16. The distal inversion 124 a defining the second segment 144 a can also begin to form as the braid 110 is pushed out of the microcatheter 600. As illustrated in FIGS. 2E through 2F, the “S” shape of the second segment 144 a can begin to form as the braid 110 is further pushed from the microcatheter 600.
As illustrated in FIG. 2G, once the first portion of the braid 110, which can comprise the first segment 142 a, second segment 144 a, and third segment 146 a, is in place within the aneurysm sac 12, the fourth segment 152 a can radially expand outside the aneurysm 10 as the distal portion of the braid 110 continues to exit the microcatheter 600.
As illustrated in FIG. 2H, the fourth segment 152 a can then be compressed distally as it continues to radially expand, compressing the fourth segment 152 a up into the first portion of the braid 110.
Finally, as illustrated in FIG. 2I, the fourth segment 152 a can be compressed distally into the first portion of the braid 110, at least partially occluding the neck 16 of the aneurysm 10 and the neck opening 126. The pinched end 112 and/or the detachment point 150 can remain external to the aneurysm sac once the fourth segment 152 a has reached its final expanded and compressed state. The fourth segment 152 a when compressed can be compressed to a minimal thickness as to not become an obstruction to the surrounding blood vessels.
Before the implant 100 is released from the delivery system, the implant 100 can be partially or fully retracted into the microcatheter 600 and repositioned.
FIG. 3A is a flow diagram for a method 300 for forming an occlusive device to treat an aneurysm 10. Step 310 includes selecting an implant comprising a tubular braid, an open end, and a pinched end. Step 320 includes shaping the tubular braid to a predetermined shape, such as the one illustrated in FIG. 1A. As illustrated in FIG. 3B, step 320 can further comprise additional steps. Step 322 includes inverting the tubular braid to form a distal inversion. Step 324 inverts the tubular braid to form a proximal inversion by moving the open end over at least a portion of the braid. Step 326 includes shaping a first segment of the tubular braid extending between the open end and the proximal inversion. Step 328 shapes a second segment of the tubular braid extending between the proximal inversion and the distal inversion. Step 330 includes positioning the open end to encircle the second segment. Step 332 shapes a third segment extending from the distal inversion to the proximal inversion. Step 334 includes positioning the second segment to surround the third segment. Step 336 shapes a fourth segment of the tubular braid extending from the third segment radially outward from a central axis to cross the proximal inversion, fold inwardly toward the central axis, and converge at the pinched end. Step 338 includes positioning the fourth segment approximate a neck of an aneurysm.
In method 300, step 320 of shaping the tubular braid to the predetermined shape can further include shaping the fourth segment to comprise a diameter greater than or approximately equal to a maximum diameter of the first segment. In method 300, the step 320 of shaping the tubular braid to the predetermined shape can further include shaping the fourth segment to a diameter lesser than a maximum diameter of the first segment. The method 300 can further include shaping the tubular braided implant to a delivery shape sized to traverse a lumen of a microcatheter.
FIG. 4A is a flow diagram for a method 400 for a method for treating an aneurysm 10. Step 410 positions a first portion of a tubular braided implant, the tubular braided implant comprising a tubular braid, an open end, and a pinched end, within a sac of the aneurysm such that the first portion circumferentially apposes walls within the sac. The first portion can include one or more inversions. Step 420 includes expanding a second portion of the tubular braided implant radially to occlude a majority of a neck of the aneurysm. Step 430 presses the second portion distally into the first portion. Pressing the second portion distally into the first portion can create three layers of braid at the neck of the aneurysm. The second portion can cover any spatial gaps between the first portion and the aneurysm neck, and can potentially increase metal coverage, decrease porosity of the implant, and increase stasis and blood flow diversion at the neck of the aneurysm to promote the sealing and healing of the aneurysm. Step 440 includes moving the first portion of the tubular braided implant toward a distal portion of the aneurysm wall as a result of pressing the second portion distally into the first portion.
As illustrated in FIG. 4B, step 420 can further include step 422, which includes positioning a fold in the second segment to define a substantially circular perimeter of the second portion. Step 420 can additionally, or alternatively include step 424, which includes compressing the second portion along a central axis of the tubular braided implant such that the second portion comprises a substantially circular shape having an area and the second portion comprises two layers of braid over a majority of the area of the substantially circular shape.
Step 410 can further include shaping the tubular braided implant to form a columnar post encircling a central axis of the tubular braided implant and extending a majority of a height of the first portion. Step 410 can further include positioning a proximal inversion in the first portion of the tubular braided implant approximate the neck of an aneurysm and positioning a distal inversion in the first portion of the tubular braided implant approximate the distal portion of the aneurysm wall. Step 410 can further include positioning the open end of the tubular braided implant to circumferentially appose the aneurysm wall, shaping a first segment of the tubular braid extending between the open end and the proximal inversion to appose an at least a portion of a wall of the aneurysm within the aneurysm's sac, and shaping a second segment of the tubular braid such that the first segment provides an outwardly radial force in a plane defining a boundary between the aneurysm and blood vessel branches, the force sufficient to appose the first segment to walls of the aneurysm.
Step 430 can further include pressing the second portion of the tubular braided implant against the proximal inversion in the first portion of the tubular braided implant. Step 440 can further include moving the distal inversion in the first portion of the tubular braided implant toward the distal portion of the aneurysm wall.
The method 400 can further include shaping the tubular braided implant to form a columnar post encircling a central axis of the tubular braided implant and extending a majority of a height of the first portion. The method 400 can further include retracting the tubular braid until a desired position is achieved relative to the aneurysm. The method 400 can further comprise shaping the tubular braided implant to a delivery shape sized to traverse a lumen of a microcatheter.
FIGS. 5A through 5B are illustrations of an example braided implant 200 as it is formed into a predetermined shape (FIG. 5B). The implant 200 can treat a range of aneurysm sizes. The implant 200 can include a tubular braid 210 having an open end 214 and a pinched end 212, similar to FIGS. 1A and 1B. The tubular braid 210 can include memory shape material that can be heat set to a predetermined shape, can be deformed for delivery through a catheter, and can self-expand to an implanted shape that is based on the predetermined shape and confined by the anatomy of the aneurysm in which it is implanted.
When in the predetermined shape, the tubular braid 210 can be substantially radially symmetrical about a central vertical axis. The implant 200 can include a connection and detachment feature 150 as illustrated in prior figures. The pinched end 212 can include a marker band and/or soldered point with visibility, and/or the connection feature 150 can include radiopaque material. The tubular braid 210 can be formed in the predetermined shape (FIG. 5B), collapsed to a delivery shape with a single layer of braid 210 for delivery through a microcatheter similar to FIG. 2A, attached to a delivery system at connection feature 150, and implanted in an implanted shape such as the ones shown in FIGS. 6A-6C in a manner similar to the delivery described in FIGS. 2A through 2F.
Referring to FIG. 5A, the tubular braid 210 can include two inversions, 222, 224, a pinched end, 212, and an open end 214. The tubular braid 210 as depicted in FIG. 5A can include four segments, 242, 244, 246, and 248. The first segment 242 can extend from the open end 214 of the tubular braid 210 to a proximal inversion 222. The second segment 244 can be encircled by the open end 214 and can extend from the proximal inversion 222 to a distal inversion 224. The third segment 246 can be surrounded by the second segment 244.
The tubular braid can be formed into a predetermined shape by first inverting the braid 210 outwardly to separate the third segment 246 from the second segment 244 with a distal inversion 224. Then, the second segment 244 can be shaped over a form or mold. The form can be in the shape of a sack. Next, the braid 210 can be inverted outwardly again to separate the second segment 244 from the first segment 242 with a proximal inversion 222.
As further illustrated in FIG. 5A, the third segment 246 can span from the distal inversion 224 to the ball segment 248. The first segment 242, second segment 244, and third segment 246 can form a first portion of the tubular braid 210. The ball segment 248 can extend from a proximal portion of the third segment 246 radially outward from a central axis of the tubular braid 210 to form a substantially ellipsoid shape and converge at the pinched end 212. A mold 220 can be applied, and this form wherein the ball segment 248 is shaped can be treated with heat in order to set the predetermined shape as depicted in FIG. 5B.
As seen in FIG. 5B, the ball segment 248 can be pressed distally into the first portion of the tubular braid 210. When the ball segment 248 is pressed distally into the first portion of the tubular braid 210, the ball segment 248 can provide a radially outward force to appose the proximal inversion 222. Further, when the ball segment 248 is pressed distally into the first portion of the tubular braid 210, the ball segment 248 can be at least partially enclosed within the second segment 244 distal to the proximal inversion 222. The ball segment 248 can also be fully enclosed within the second segment 244 distal to the proximal inversion 222. When the tubular braid 210 is in the predetermined shape, the second segment 244 can form a sack, and at least a portion of the third segment 246 can positioned within the sack and at least a portion of the ball segment 248 can be positioned external to the sack. The ball segment 248 can occlude at least a portion of the proximal inversion 222 to seal the opening created by the proximal inversion 222.
FIGS. 6A through 6C are illustrations of an example braided implant 200 implanted within an aneurysm 10. The tubular braid 210 can be radially or vertically compressed or extended compared to the predetermined shape to conform to aneurysms of varying sizes, heights, and shapes. As illustrated in FIG. 6A, when in the implanted shape in an aneurysm 10 with a height H1, the braid 210 can have an outer layer 242 a corresponding to the first segment 242 of the predetermined shape and positioned to contact an aneurysm wall 14 of the aneurysm 10, a proximal inversion 222 a corresponding to the proximal inversion 222 of the predetermined shape and positioned to be placed approximate a neck 16 of the aneurysm 10, and a sack 244 a corresponding to the second segment 244 of the predetermined shape and positioned to appose the outer layer 242 a. A distal inversion 224 a can correspond to the distal inversion 224 of the predetermined shape, and a third segment 246 a can correspond to the third segment 246 in the predetermined shape. The braid 210 can also have a ball segment 248 a corresponding to the ball segment 248 of the predetermined shape and extending from the third segment 246 a radially outward from a central axis to form a substantially ellipsoid shape and converge at the pinched end 212. As described in FIG. 5B, the ball segment 248 a can be pressed distally into the first portion of the tubular braid 210. Pressing the ball segment 248 a distally into the first portion of the tubular braid 210 can result in multiple layers of braid 210 seated at the neck 16 of the aneurysm 10. These multiple layers of braid 210 can inhibit blood flow into the aneurysm 10 by better occluding the aneurysm neck 16, by better occluding the channel formed by the proximal inversion 222 a, or both.
As illustrated in FIG. 6A, when implanted, the ball segment 248 a can be positioned external to the aneurysm 10, extending across the aneurysm neck 16. The ball segment 248 a can occlude at least a portion of the aneurysm neck 16. The ball segment 248 a can also occlude at least a portion of the proximal inversion 222 a to seal the opening created by the proximal inversion 222 a.
FIG. 6B depicts an implant 200 in an aneurysm 10 with a height H2. The height H2 of the aneurysm in FIG. 6B can be greater than the height H1 of the aneurysm in FIG. 6A. By pressing the ball segment 248 a into the first portion of the tubular braid 210 within an aneurysm with a height H2, the first portion 242 a, 244 a, 246 a of the tubular braid 210 can be moved further into the aneurysm 10 towards the distal portion of an aneurysm wall 15. The ball segment 248 a can occlude at least a portion of the neck 16 of the aneurysm 10. The ball segment 248 a can also occlude at least a portion of the proximal inversion 222 a to seal the opening created by the proximal inversion 222 a. Pushing the ball segment 248 a into the first portion of the braid 210 can also appose the proximal inversion 222 to provide a radially outward force against the proximal inversion 222 so that the tubular braid 210 apposes a wall 14 of the aneurysm 10 approximate a neck 16 of the aneurysm 10.
Alternatively, pushing the ball segment 248 a distally into the first portion of the tubular braid 210 can push the third segment 246 a distally into the aneurysm towards a distal portion of the aneurysm wall 15, independent of distal movement of the outer layer 242 a and/or sack 244 a. This can extend the height of the implant 200 to better conform to the height of the aneurysm H2. At least a portion of the ball segment 248 a can be enclosed by the sack 244 a. At least a portion of the ball segment 248 a can be positioned external to the sack 244 a.
As illustrated in FIG. 6C, the implant 200 can be deployed within an aneurysm with a height H3 greater than H1 and H2 in FIGS. 6A and 6B respectively. As seen here, the ball segment 248 a can be pushed distally even further into the first portion of the tubular braid 210 until it is completely enclosed within the sack 244 a. By pressing the ball segment 248 a into the first portion of the tubular braid 210 within an aneurysm with a height H3, the first portion 242 a, 244 a, 246 a of the tubular braid 210 can be moved towards the distal portion of an aneurysm wall 15. Alternatively, as described in FIG. 6B, pushing the ball segment 248 a distally into the first portion of the tubular braid 210 can push the third segment 246 a distally into the aneurysm towards a distal portion of the aneurysm wall 15, independent of distal movement of the outer layer 242 a and/or sack 244 a. This can extend the height of the implant 200 to better conform to the height of the aneurysm H3. The ball segment 248 a can occlude at least a portion of the aneurysm neck 16. The ball segment 248 a can also occlude at least a portion of the proximal inversion 222 a to seal the opening created by the proximal inversion 222 a. In this way, the implant 200 can be used to treat implants of varying heights and widths depending on the positioning of the ball segment 248 relative to the first portion of the braid 210.
FIG. 7 is a flow diagram for a method 700 for treating an aneurysm 10. The method 700 can be utilized to treat aneurysms of varying sizes, heights, and shapes with a single device. Step 710 positions a first portion of a tubular braided implant, the tubular braided implant having a tubular braid, an open end, and a pinched end, within a sac of the aneurysm such that the first portion circumferentially apposes walls within the sac. The first portion can include one or more inversions, including a distal inversion approximate a distal portion of the aneurysm wall. Step 720 includes expanding a second portion of the tubular braided implant in connection with the first portion of the tubular braided implant radially to occlude a majority of the neck of the aneurysm. Step 730 presses the second portion distally into the first portion to provide a radial force against the first portion towards the aneurysm wall approximate the neck of the aneurysm in a plane defining a boundary between the aneurysm and blood vessel branches. Lastly, Step 740 moves the distal inversion toward a distal portion of the aneurysm wall as a result of pressing the second portion distally into the first portion.
The step 710 of positioning the first portion of the tubular braided implant can further include positioning the open end of the tubular braided implant to circumferentially appose the aneurysm wall, positioning a proximal inversion in the first portion of the tubular braided implant approximate the neck of an aneurysm; and shaping a first segment of the tubular braid extending between the open end and the proximal inversion to appose an at least a portion of a wall of the aneurysm within the aneurysm's sac.
The step 720 of expanding the second portion of the tubular braided implant can further include compressing the second portion along a central axis of the tubular braided implant such that the second portion forms a substantially ellipsoidal shape.
The step 730 of pressing the second portion distally into the first portion can further include apposing at least a part of the first portion with the second portion to provide an outwardly radial force along a central axis of the tubular braided implant from the second portion to the first portion. The step 730 of pressing the second portion distally can also involve pressing the second portion of the tubular braided implant against the proximal inversion in the first portion of the tubular braided implant until the second portion of the tubular braided implant is at least partially enclosed by the proximal inversion. The step 730 of pressing the second portion distally can also disrupt the flow of blood into the aneurysm by placing multiple layers of braid approximate the neck of the aneurysm.
The method 700 can further include shaping the tubular braided implant to a delivery shape with a single layer of braid sized to traverse a lumen of a microcatheter.
FIG. 8 is a flow diagram for a method of forming an occlusive device to treat an aneurysm. The method can include inverting a tubular braid comprising an open end and a pinched end to form a distal inversion (810); inverting the tubular braid to form a proximal inversion by moving the open end over at least a portion of the braid (820); shaping a first segment of the tubular braid extending between the open end and the proximal inversion (830); shaping a second segment of the tubular braid extending between the proximal inversion and the distal inversion (840); positioning the open end to encircle the second segment (850); shaping a third segment extending from the distal inversion to the pinched end (860); positioning the second segment to surround the third segment (870); shaping a ball segment of the tubular braid extending from the third segment radially outward from a central axis to form a substantially ellipsoid shape and converge at the pinched end (880); and applying a mold to the ball segment of the tubular braid and treating the ball segment with heat to conform the ball segment to the formed shape, the ball segment movable along a central axis of the tubular braid (890).
The method 800 can further include positioning the first segment, second segment, and third segment within an aneurysm, and advancing the ball segment distally into the proximal inversion. This step of advancing the ball segment distally into the proximal inversion can move the distal inversion towards a distal portion of a wall of the aneurysm, which can conform the device to the height of the aneurysm. In this manner, the device can be used to treat aneurysms of varying heights, shapes, and sizes.
The method 800 can also include apposing the proximal inversion with at least a portion of the ball segment. The method 800 can further include moving the ball segment to a position at least partially enclosed by the second segment distal to the proximal inversion. The method 800 can also involve retracting the tubular braid until a desired position is achieved relative to the aneurysm.
As used herein, the terms “about” or “approximately” for any numerical values or ranges indicate a suitable dimensional tolerance that allows the part or collection of components to function for its intended purpose as described herein.
The descriptions contained herein are examples of embodiments of the invention and are not intended in any way to limit the scope of the invention. The invention contemplates many variations and modifications of the implant, including: alternative delivery methods, alternative braid materials, alternative means for achieving a desired stiffness/flexibility of braid material, additional structures affixed to the implant (e.g. to aid in anchoring the implant, blood flow diversion, embolism formation, etc.), alternative predetermined braid shapes (e.g. one inversion, three inversions, four inversions, five or more inversions, non-radially symmetric shapes, alternative segment shapes, etc.), alternative implanted shapes, etc. The invention contemplates many variations and modifications to constructing the implant to include combinations of the aforementioned variations and modifications of the implant. The invention contemplates many variations and modifications of implanting the implant to accommodate combinations of the aforementioned variations and modifications of the implant. Modifications apparent to one of ordinary skill in the art following the teachings of this disclosure are intended to be within the scope of the claims which follow.

Claims

What is claimed is:

1. A method for treating an aneurysm, the method comprising:

positioning a first portion of a tubular braided implant, the tubular braided implant comprising a tubular braid, an open end, and a pinched end, within a sac of the aneurysm such that the first portion circumferentially apposes walls within the aneurysm sac, extends from the open end of the tubular braid, and comprises one or more inversions, including a distal inversion positioned approximate a distal portion of the aneurysm wall;

expanding a second portion of the tubular braided implant in connection with the first portion of the tubular braided implant radially to occlude a majority of a neck of the aneurysm;

pressing the second portion distally into the first portion to provide a radial force against the first portion towards the aneurysm wall approximate a neck of the aneurysm; and

moving the distal inversion toward a distal portion of the aneurysm wall as a result of pressing the second portion distally into the first portion,

wherein the second portion is pressed distally into the first portion in a plane defining a boundary between the aneurysm and a blood vessel branch.

2. The method of claim 1, wherein expanding the second portion of the tubular braided implant further comprises:

compressing the second portion along a central axis of the tubular braided implant such that the second portion forms a substantially ellipsoidal shape.

3. The method of claim 1, further comprising shaping the tubular braided implant to a delivery shape comprising a single layer of braid and sized to traverse a lumen of a microcatheter.

4. The method of claim 1, wherein pressing the second portion distally into the first portion further comprises apposing at least a part of the first portion with the second portion to provide an outwardly radial force along a central axis of the tubular braided implant from the second portion to the first portion.

5. The method of claim 1, wherein pressing the second portion distally into the first portion disrupts the flow of blood into the aneurysm by placing multiple layers of braid approximate the neck of the aneurysm.

6. The method of claim 1, wherein positioning the first portion of the tubular braided implant further comprises:

positioning the open end of the tubular braided implant to circumferentially appose the aneurysm wall;

positioning a proximal inversion in the first portion of the tubular braided implant approximate the neck of an aneurysm; and

shaping a first segment of the tubular braid extending between the open end and the proximal inversion to appose an at least a portion of the wall of the aneurysm within the aneurysm's sac.

7. The method of claim 6,

wherein pressing the second portion distally into the first portion further comprises pressing the second portion of the tubular braided implant against the proximal inversion in the first portion of the tubular braided implant until the second portion of the tubular braided implant is at least partially enclosed by the proximal inversion, providing an outwardly radial force in a plane defining a boundary between the aneurysm and blood vessel branches.

8. The method of claim 1,

wherein pressing the second portion distally into the first portion further comprises enclosing the second portion of the tubular braided implant within the first portion of the tubular braided implant.

9. A method for treating an aneurysm, the method comprising:

positioning a first segment of a tubular braided implant, the tubular braided implant comprising a tubular braid, an open end, and a pinched end, within a sac of the aneurysm such that the first segment extends from the open end of the tubular braid to a proximal inversion;

positioning a second segment of the tubular braided implant within the aneurysm sac, the second segment encircled by the open end and extending from the proximal inversion to a distal inversion; and

positioning a third segment of the tubular braided implant within the aneurysm sac, the third segment surrounded by the second segment and extending from the distal inversion, and

advancing a ball segment depending from the third segment distally into the proximal inversion, the ball segment extending radially outward from a central axis, providing a radially outward force, and converging at the pinched end to appose the proximal inversion.

10. The method of claim 9, wherein the ball segment is enclosed by the second segment distal to the proximal inversion.

11. The method of claim 9, wherein when the tubular braided implant is implanted in the aneurysm, the ball segment occludes at least a portion of an aneurysm neck.

12. The method of claim 9, wherein the radially outward force is exerted against the proximal inversion so that the tubular braided implant contacts a wall of the aneurysm approximate a neck of the aneurysm.

13. The method of claim 9, wherein when the tubular braided implant is implanted in the aneurysm, the second segment forms a sack, at least a portion of the third segment is positioned within the sack, and at least a portion of the ball segment is positioned external to the sack.

14. The method of claim 9, wherein when the tubular braided implant is implanted in the aneurysm,

the first segment forms an outer layer positioned to contact an aneurysm wall of the aneurysm,

the proximal inversion is positioned to be placed approximate an aneurysm neck of the aneurysm, and

the second segment forms a sack positioned to appose a portion of the aneurysm wall of the aneurysm and to appose the outer layer.

15. A method for forming an occlusive device to treat an aneurysm comprising:

inverting a tubular braid comprising an open end and a pinched end to form a distal inversion;

inverting the tubular braid to form a proximal inversion by moving the open end over at least a portion of the braid;

shaping a first segment of the tubular braid extending between the open end and the proximal inversion;

shaping a second segment of the tubular braid extending between the proximal inversion and the distal inversion;

positioning the open end to encircle the second segment;

shaping a third segment extending from the distal inversion to the pinched end;

positioning the second segment to surround the third segment;

shaping a ball segment of the tubular braid extending from the third segment radially outward from a central axis to form a substantially ellipsoid shape and converge at the pinched end; and

applying a mold to the ball segment of the tubular braid and treating the ball segment with heat to conform the ball segment to the formed shape, the ball segment movable along a central axis of the tubular braid.

16. The method of claim 15 further comprising:

positioning the first segment, second segment, and third segment within an aneurysm, and

advancing the ball segment distally into the proximal inversion.

17. The method of claim 16, whereby advancing the ball segment distally into the proximal inversion moves the distal inversion towards a distal portion of a wall of the aneurysm to conform the device to the height of the aneurysm.

18. The claim of method 16, further comprising moving the ball segment to a position at least partially enclosed by the second segment distal to the proximal inversion.

19. The method of claim 16, wherein when the tubular braided implant is implanted in the aneurysm, the ball segment occludes at least a portion of an aneurysm neck.

20. The method of claim 16, wherein the ball segment provides a radially outward force, the radially outward force being exerted against the proximal inversion so that the tubular braided implant contacts a wall of the aneurysm approximate a neck of the aneurysm.