Multi-layer foldable flow diverter

Abstract

A tubular, collapsible flow diverter is provided. The flow diverter includes multiple sections, including a first section, a second section, and a third section. The flow diverter is moldable into an elongated cylindrical shape and is convertible to an implantable configuration. In the implantable configuration, the second section overlaps with at least a portion of the first and third sections to form a three-layered shape. This three-layered shape can be positioned adjacent to the aneurysm neck when implanted in a patient. The overall porosity of the implant can be higher than conventional implants because the overlapping portions of the three sections can reduce porosity adjacent to the aneurysm neck.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit and priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 059,524, filed on July 31, 2020, which is hereby incorporated by reference herein in its entirety.

[0002] The present invention generally relates to medical devices, and more particularly to embolization implants for the treatment of aneurysms.

Background Art

[0003] Cranial aneurysms are complex and can be difficult to treat due to their proximity to vital brain tissue. Previous solutions include endovascular procedures that remove or exclude the internal volume of the aneurysm sac from arterial blood pressure and blood flow. Current alternatives to endovascular or other surgical techniques can include endovascular delivery treatment devices that fill the aneurysm sac with embolization material or occlude the aneurysm's inlet or neck. Both techniques attempt to prevent blood flow into the aneurysm. When filling the aneurysm sac, the embolization material coagulates blood and forms a thrombus mass within the aneurysm. When treating the aneurysm neck, blood flow into the aneurysm's inlet is blocked, inducing venous stasis within the aneurysm and promoting the natural formation of a thrombus mass within the aneurysm.

[0004] Current intravascular delivery devices typically utilize a plurality of embolization coils to either fill the aneurysm sac or treat the aneurysm neck. A naturally formed thrombus clot formed by treating the neck with an embolization coil can reduce the potential for dilation from the arterial wall and facilitate re-integration into the original parent vessel shape along the neck plane, so the naturally formed thrombus clot can result in improved healing compared to the aneurysm mass encapsulated by the embolization coil. However, embolization coils delivered to the aneurysm neck can potentially have the adverse effect of obstructing blood flow when contacting the blood vessel, especially when the neck is overly encapsulated. Conversely, if the neck is not sufficiently encapsulated, blood flow may remain within the aneurysm. Treatment of certain aneurysm morphologies (e.g., wide necks, bifurcations, etc.) may require an adjunct device such as a stent or balloon to support the coil mass and achieve the desired packing density. Once implanted, the coils cannot be easily retracted or repositioned. Furthermore, aneurysms treated with multiple coils often experience recanalization or compression due to poor coiling, incomplete coverage of the entire aneurysm neck, or large blood flow or aneurysm size, so embolization coils do not always effectively treat aneurysms. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0005] Alternatives to coil plugs are being considered, for example, in the form of a tubular braided flow diverter. A braided flow diverter typically includes a braided material that acts to slow blood flow into the aneurysm and prevent the aneurysm from clotting. The braided material typically consists of a single layer of 48 to 96 wires to exhibit a 70% porous structure. A 70% porosity has been clinically proven to be dense enough to treat aneurysms but porous enough not to occlude collateral vessels. However, this type of braiding can be difficult to deliver in a microcatheter, especially in highly tortuous anatomical structures. This may be due to the overall porosity of the braid itself, as the 70% porous braid still contains 30% of the material by volume and is thus relatively rigid.

[0006] Therefore, there is a need for improved methods, devices, and systems for flow diverters that can occlude aneurysms and be easily deployed through a microcatheter.

Means for Solving the Problem

[0007] It is an object of the present invention to provide a system, device, and method that meet the above-described needs. Generally, an object of the present invention is to provide a vascular flow diverter that can be delivered in a delivery configuration and folded into an implanted configuration. The vascular flow diverter can have a first tubular section that defines an inner lumen. A third tubular section can be disposed within the inner lumen of the first tubular section. A second tubular section can be disposed between the first tubular section and the third tubular section. In the delivery configuration, the first tubular section, the second tubular section, and the third tubular section can define a single-layer cylindrical shape. In the implanted configuration, the second tubular section can overlap at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section.

[0008] The porosity of the first tubular section, the third tubular section, and the second tubular section can be higher than that of a conventional braided mesh design. For example, the first tubular section, the third tubular section, and the second tubular section can be a braided mesh having a porosity of about 80% to about 90%.

[0009] When the flow diverter for blood vessels is in an implanted configuration, the three-layer shape adjacent to the second tubular section can have a porosity of about 50% to about 70%. As described above, a porosity of 70% or less has been clinically proven to be a sufficient density for treating aneurysms.

[0010] In some embodiments, the second tubular section can have a different porosity than the first tubular section and the third tubular section.

[0011] The first tubular section, the third tubular section, and the second tubular section can each include a braided mesh. The braided mesh of the second tubular section can have a different braiding angle than the braided meshes of the first tubular section and the third tubular section.

[0012] The second tubular section can have a first material thickness, and the first tubular section and the third tubular section can have a second material thickness. The first material thickness can be smaller than the second material thickness.

[0013] The first bending point can be disposed between the first tubular section and the second tubular section, and the second bending point can be disposed between the third tubular section and the second tubular section. The bending points can help facilitate folding from the delivery configuration to the implanted configuration.

[0014] One of the first tubular section and the third tubular section can include a braided mesh. The other of the third tubular section and the first tubular section can include a laser cut stent.

[0015] The second tubular section can include an antithrombotic coating. The coating adjacent to the aneurysm can help prevent in-stent stenosis.

[0016] Another object of the present invention is to provide an implant that can be formed into a cylindrical shape and can be transitioned into an implanted shape. The implant can include a first section having a first outer layer. The implant can include a second section having a second outer layer that can be folded to contact the first outer layer. The implant can include a third section including a third outer layer that can be folded to contact the second outer layer. When in the implanted shape, the implant can have a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer. When in the implanted shape, the three-layer overlapping section can be disposed adjacent to the aneurysm neck.

[0017] The second section can include a braided mesh having a porosity of about 80% to about 90%. When in the implanted shape, the three-layer overlapping section can have a porosity of about 50% to about 70%.

[0018] The first section, the third section, and the second section can each include a braided mesh. The braided mesh of the second section can have a braiding angle different from that of the braided meshes of the first section and the third section.

[0019] The implant can include a first bending point disposed between the first section and the second section. The implant can include a second bending point disposed between the third section and the second section.

[0020] One of the first section and the third section can include a braided mesh. The other of the third section and the first section can include a laser-cut stent. In some embodiments, the second section can also include a braided mesh. The braided mesh of the second section can have a first plurality of looped ends. The laser-cut stent can include a second plurality of looped ends. At least a portion of the first plurality of looped ends can be woven with at least a portion of the second plurality of looped ends. Another attachment mechanism for attaching the laser-cut stent to the braided mesh includes a clip having an outer strut member and a central strut member. The outer strut member can be disposed on one side of the braided mesh, and the central strut member can be disposed on the other side of the braided mesh. The outer strut member and the central strut member can be attached at a fixed position so as to permanently connect the stent to the braided mesh.

[0021] The second section can include an antithrombotic coating. The coating proximate to the aneurysm neck can help prevent in-stent stenosis.

[0022] Another object of the present invention is to provide a method for delivering a flow diverter. The method can include deploying a first section of the flow diverter distally of the aneurysm neck through a blood vessel via a catheter. The method can include deploying and inverting a second portion of the flow diverter to bring a second section into contact with the inner lumen of the first section. The method can include positioning the second section of the flow diverter such that the second section traverses the aneurysm neck. The method can include moving the catheter proximally of the aneurysm neck and simultaneously deploying a third section of the flow diverter via the catheter. The method can include forming an overlapping section of the flow diverter proximate to the aneurysm neck, the overlapping section including at least a portion of the first section, the second section, and the third section.

[0023] The first section, the third section, and the second section can include a braided mesh having a porosity of about 80% to about 90%. The step of forming the overlapping section can reduce the porosity of the flow diverter proximate to the overlapping section to about 50% to about 70%.

[0024] At least one of the first section or the third section can include a laser-cut stent. The second section can include a braided mesh connected to the laser-cut stent. The method can include folding the flow diverter at the connection between the braided mesh and the laser-cut stent. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and further aspects of the present invention will be further considered with reference to the following description in conjunction with the accompanying drawings, in which like numerals in the various drawings indicate like structural elements and features. The drawings are not necessarily to scale, and instead, the focus is placed on illustrating the principles of the present invention. The figures depict one or more implementations of the device of the present invention by way of illustration and not limitation.

Figure 1

Figure 2A

Figure 2B

Figure 3A

Figure 3B

Figure 3C

Figure 3D

Figure 3E

Figure 3F

Figure 4A

Figure 4B

Figure 4C

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Figure 6A

Figure 6B

Figure 6C

Figure 7

DETAILED DESCRIPTION OF THE INVENTION

[0026] In known treatments for wide-necked aneurysms, the aneurysm is typically treated by placing an embolization coil within the aneurysm sac and placing a stent within the parent vessel across the aneurysm neck. The stent is often used to prevent the embolization coil from entering the parent vessel. If the embolization coil enters the parent vessel, the coil may occlude the vessel and / or a blood clot may form on the coil within the vessel, forming an occlusion within the parent vessel. A braided aneurysm implant can be used to treat wide-necked aneurysms instead of an embolization coil. To achieve the force necessary to secure the braided implant to the wide-necked bifurcation, a balance must be struck between rigidity and porosity. The braid should have sufficient rigidity to maintain its implanted shape and not collapse within the blood vessel. Rigidity can be increased by increasing the material density of the flow diverter, or in other words, by decreasing the porosity of the implant.

[0027] However, increasing rigidity by decreasing porosity can cause several additional problems. First, increasing rigidity may make it more difficult for the implant to move to its intended location through a highly tortuous anatomical structure. Second, decreasing porosity may also decrease the effectiveness of the porous implant with respect to occluding the aneurysm. For example, a braided implant can be used to bridge the aneurysm such that blood flow passes through the implant but flow into the aneurysm is blocked. To further block flow into the aneurysm, the porosity of the mesh can be decreased.

[0028] Furthermore, there is another problem regarding the porosity of the braided implant. That is, if the porosity is overly low, there is a risk that the implant may occlude the collateral vessels adjacent to the implant. A porosity of about 70% has been shown to be dense enough to treat aneurysms but porous enough not to occlude collateral vessels. For this purpose, prior art braided implants typically have a porosity of about 70%. These conventional designs for braiding can be difficult to deliver with a microcatheter, especially in highly tortuous anatomical structures, or they require a large-sized microcatheter to pass through the implantation site.

[0029] One aspect of the present disclosure is to provide a solution to the above problems. In particular, the present devices, systems, and methods describe a solution that allows the implant to have a lower overall porosity than conventional implant designs. The lower porosity allows the implant to be positioned at the treatment site more easily than conventional designs, and further reduces the risk of occluding collateral vessels. However, since the present devices, systems, and methods relate to blocking blood flow within the aneurysm, they do not reduce the effectiveness of the implant. To achieve this, the present devices, systems, and methods describe a multilayer collapsible flow diverter that provides an overlapping section of the implant adjacent to the aneurysm when implanted.

[0030] Aspects of the present invention include an implant that is foldable from a delivery configuration to an implanted configuration. In the delivery configuration, the implant can have an elongated tubular form. The implant can then be folded such that an intermediate section, i.e., a second section described below, is sandwiched between two end sections (i.e., a first section and a third section below). As used herein, the terms “tubular” and “tube” are to be construed broadly and are not limited to a structure having a cross-section that is a right circular cylinder structure or strictly circular, or a structure having a uniform cross-section over its entire length. For simplicity, the tubular structure is generally shown herein as having a substantially straight cylindrical shape. However, the tubular structure can have a tapered or curved outer surface without departing from the scope of the present invention.

[0031] Various devices, systems, and methods have been disclosed for providing a collapsible flow diverter, and examples of the devices, systems, and methods are described herein with reference to the accompanying drawings. FIG. 1 is a side view of a flow diverter 100 in a delivery configuration according to an aspect of the present invention. The flow diverter 100 can have an elongated tubular shape defined by three sections, as shown in the figure. A first section 102 and a third section 106 can be at the ends of the flow diverter 100, and a second section 104 is disposed between the first section 102 and the third section 106. As described in more detail below with reference to FIG. 2A, in the implanted configuration, the third section 106 can overlap a portion of the first section 102, thereby positioning the second section 104 between the two end sections.

[0032] The flow diverter 100 can include a braided mesh 108. The braided mesh 108 can include a number of strands, for example, from about 4 to about 96 strands, and each strand extends from the distal end of the first section 102 to the proximal end of the third section 106. As used herein, the term "about" or "approximately" with respect to any numerical value or range of numerical values indicates a tolerance of suitable dimensions that enables a component part or set of component parts to function in accordance with its intended purpose as described herein. More specifically, "about" or "approximately" may refer to a range of values that are ±20% of the stated value. For example, "about 90%" may refer to a range of values from 71% to 99%.

[0033] The strands can be helically wound around the flow diverter (or outer layers 204, 206, 208 described below with reference to FIGS. 2A and 2B). The number of strands, the angle of the strands, the diameter of the strands, the material of the strands, and the material properties of the strands can all be factors that control the material properties of the braided mesh 108, including porosity and flexibility. For example, the pores 110 are defined by the absence of strand material. When referring to porosity herein, it will be understood that it means the percentage of the surface area of the implant defined by the pores 110 within the braided mesh 108. By way of illustration, if the pores 110 of the flow diverter 100 define 10% of the outer surface of the implant, the implant is said to have a porosity of 10%.

[0034] Referring again to the braided mesh 108, the braided strands can be woven such that approximately half of the strand wraps are helically wound clockwise and the other half are helically wound counterclockwise, with the strands wound in opposite directions crossing over each other vertically in an alternating pattern. By having such a configuration, portions of the braid with a higher braiding angle can have a higher strand density compared to portions of the braid with a lower braiding angle. The higher strand density can result in a more dense and rigid braided portion. With reference to FIG. 4A, the braiding angle is described in more detail below.

[0035] The strands can be made from a plurality of alloys such as nickel-titanium alloy, cobalt-chromium alloy, platinum, nitinol, stainless steel, tantalum, or other alloys, or any other suitable biocompatible material, or combinations of these materials. Also, the materials used to make the braided mesh 108 can be absorbable or non-absorbable by the patient over time. Part or all of the braided mesh 108 can preferably be a multi-filament cylindrical mesh made of nitinol with woven platinum filaments or Drawn Filled Tube (DFT) nitinol with about 10% to about 40% platinum for radiopacity.

[0036] The second section 104 can have an antithrombotic coating to prevent in-implant stenosis. For example, the second section 104 can be coated with an antithrombotic coating such as heparin, phosphorylcholine, a hydrophilic coating, or any other such coating that would be recognized and understood by one of ordinary skill in the art.

[0037] Figures 2A and 2B show the flow diverter 100 in an implanted configuration according to aspects of the present disclosure. FIG. 2A is a partial cross-sectional side view, and FIG. 2B is a cross-sectional end view showing the overlap section 202. In the implanted configuration, the second section 104 can overlap at least a portion of the first tubular section 102 and the third section 106, thereby forming an overlap section 202 proximate to the second section 104. This overlap section 202 can be positioned at the location of the aneurysm neck when the flow diverter 100 is implanted.

[0038] Each of the three sections 102, 104, 106 of the flow diverter 100 described above can include an outer layer that defines the tubular structure of the implant. The first section 102 can include a first outer layer 204, the second section 104 can include a second outer layer 206, and the third section 106 can include a third outer layer 208. When the flow diverter 100 is folded from a delivery configuration (as shown in FIG. 1) to an implanted configuration, the second outer layer 206 can be folded to contact the first outer layer 204, and the third outer layer 208 can be folded to contact the second outer layer 206, thereby forming the overlap section 202. At least a portion of the second section 104 and the third section 106 will be disposed within the inner lumen 112 defined by the first outer layer 204 of the first section 102.

[0039] As described above, an object of the present disclosure is to provide a flow diverter 100 that is easy to implant through a microcatheter and effective in occluding an aneurysm. The foldable design of the present flow diverter 100 enables these two attributes by having an overlapping section 202. Referring to FIG. 1 for illustration, the material of the braided mesh 108 of the flow diverter 100 according to this design can have a significantly higher porosity than previous flow diverter designs. For example, instead of a porosity of 70% (as seen in conventional designs), the first section 102, the second section 104, and / or the third section 106 can all have a porosity greater than 70%, for example, from about 80% to about 90%. This high porosity can enable the flow diverter 100 to be delivered more easily through a microcatheter or other access sheath.

[0040] However, the section of the flow diverter adjacent to the aneurysm can have a lower porosity than any single section alone. When the flow diverter 100 is folded into an implanted configuration, the three-layer shape of the overlapping section 202 can have a lower porosity than the non-overlapping sections. This is because the material density of the flow diverter 100 can be increased, and when multiple layers of the braided mesh 108 are stacked on top of each other, the individual strands of the braid can interfere to reduce the porosity. The overlapping section 202 (comprising the second outer layer 206 and a portion of the first outer layer 204 and the third outer layer 208) can have an overall porosity of about 50% to about 70%, which, as described above, is sufficient to block blood flow into the aneurysm. The positioning of the overlapping section 202 adjacent to the aneurysm will be described in more detail below with reference to FIGS. 3A - 3F.

[0041] Figures 3A-3F are diagrams of exemplary steps for implanting the flow diverter 100 according to aspects of the present disclosure. In Figure 3A, the distal section (e.g., the first section 102) can be deployed to a treatment site such as a blood vessel proximate to the aneurysm 12. The distal end of the first section 102 can be positioned distal to the aneurysm neck 14. In Figure 3B, once the first section 102 is deployed distal to the aneurysm neck 14, the flow diverter 100 can be inverted using the microcatheter 300 (or delivery wire). Inverting the flow diverter 100 can include pushing the microcatheter 300 into the inner lumen 112 defined by the first section 102 while simultaneously deploying the second section 104 of the flow diverter 100.

[0042] In Figure 3C, the second section 104 of the flow diverter can be deployed as the microcatheter 300 advances distally through the inner lumen 112 of the first section 102. Once the second section 104 is fully deployed within the inner lumen 112 of the first section 102, the microcatheter 300 can be pulled proximally. In Figure 3D, the microcatheter 300 is pulled proximally while simultaneously deploying the third section 106. In Figure 3E, as the third section 106 continues to deploy, the microcatheter 300 is further retracted proximally proximal to the aneurysm neck 14. In Figure 3F, the microcatheter 300 is retracted from the treatment site, and the first section 102, the second section 104, and the third section 106 overlap to form an overlapping section 202 that bridges the aneurysm neck 14.

[0043] Figures 4A - 4C are illustrative design diagrams that help facilitate the folding of the foldable flow diverter 100. Figure 4A is a side view of the flow diverter 100 having a second section 104 with a braiding angle 404 different from that of the first section 102 and the third section 106, according to an aspect of the present disclosure. The rigidity of the flow diverter 100 can be at least partially determined by the braiding angle (e.g., braiding angles 402, 404, 406 in Figure 4A). For ease of discussion, the weaker, more flexible portions of the braiding can have a smaller braiding angle compared to the stronger, more rigid portions of the braiding. However, the weaker and more rigid portions of the braiding can be processed by having different strand diameters, different numbers of strands, different strand materials, and / or by other means recognized and understood by those skilled in the art so as to have different rigidities / flexibilities.

[0044] In the single - layer tubular shape shown in Figure 4A, the braided mesh 108 can have a circumference C that is substantially uniform along the length L when the flow diverter 100 is in the delivery configuration. The tubular shape can have a central axis A extending along the length of the braided mesh 108. (The angles θ 1 , θ 2 , θ 3 shown) One or more braiding angles 402, 404, 406 can be measured by comparing the tangent trajectory of the braiding strands to the central axis A, as illustrated and as otherwise understood by those skilled in the art in accordance with the teachings of this specification. A section of the implant having a larger braiding angle, such as the second braiding angle 404 shown in the embodiment of Figure 4A, can have a lower overall porosity and can be relatively more rigid than a section having a lower braiding angle.

[0045] As shown in Figure 4A, different portions of the flow diverter 100 can have different braiding angles. For example, the second section 104 can have a second braiding angle 404 at an angle θ 2 , and the first section 102 can have an angle θ 1can have a first braiding angle 402, and the third section 106 can have a third braiding angle 406 at an angle θ 3 The angle θ 1 , θ 2 , θ 3 can all be different braiding angles, or one or more of the sections can have the same braiding angle. For example, the first braiding angle 402 and the third braiding angle 406 are intended to be the same angle, while the second braiding angle 404 is intended to be different from the angles of the first braiding angle 402 and the third braiding angle 406.

[0046] The second braiding angle 404 can be greater than the first braiding angle 402 and the third braiding angle 406 (e.g., θ 2 is greater than θ 1 and θ 3 ). This can of course also mean that the second section 104 has a lower porosity than the first section 102 and the third section 106. In this design, the center of the flow diverter 100, e.g., the overlapping section 202 when in an implanted configuration, can have a significantly lower porosity than the end of the implant. This can be beneficial for the structure since the overlapping section 202 will be implanted to block blood flow into the aneurysm. Having the lowest porosity / highest braiding density near the aneurysm neck can achieve this goal. In other examples, the second braiding angle 404 can be less than the first braiding angle 402 and the third braiding angle 406 (e.g., θ 2 is less than θ 1 and θ 3at a lower angle). This, of course, can also mean that the second section 104 is more porous than the first section 102 and the third section 106. This design allows the second section 104 to be less rigid than the end sections, thereby facilitating the folding of the flow diverter 100. However, the overlapping section 202 can still have a lower porosity than either section alone. This is because, as described above, the overlapping section 202 includes a three-layer structure that can have a lower overall porosity when in the embedded configuration.

[0047] FIG. 4B is a side view of a flow diverter 100 having a second section 104 with a material thinner than the first section 102 and the third section 106, according to an aspect of the present disclosure. The second section 104 of the flow diverter can have a material thinner than the end sections (e.g., the first section 102 and the third section 106). This can be formed by having strands of the braided mesh 108 with a smaller diameter in the second section 104. This can facilitate the folding of the second section 104 into the inner lumen defined by the first section 102.

[0048] Figure 4C is a side view of a flow diverter 100 having flexion points 408, 410 between a first section 102, a second section 104, and a third section 106, according to an aspect of the present disclosure. The flexion points 408, 410 can be positioned between adjacent sections 102, 104, 106 to facilitate folding of the flow diverter 100 from a delivery configuration to an implantation configuration. For example, the first flexion point 408 can be positioned between the first section 102 and the second section 104, and the second flexion point 410 can be positioned between the second section 104 and the third section 106. The flexion points 408, 410 can be sections of the braided mesh 108 that are weaker than the remainder of the braiding. This weaker portion can be formed by flattening, indenting, or thinning the braiding wires in that section.

[0049] Figures 5A - 5D are side views of a mechanism for attaching a section of the braided mesh 108 of the flow diverter 100 to a section of the stent 502 of the flow diverter 100, according to an aspect of the present disclosure. In these examples, one or more of the end sections (e.g., the first section 102 and / or the third section 106) can be made of stent 502 material instead of the braided mesh 108. In this structure, the flow diverter 100 can be folded at the connection points between the section of the braided mesh 108 and the section of the stent 502. As will be appreciated, the laser cut stent 502 can be more rigid than the braided mesh 108 and exert a greater outward radial force on the surrounding vasculature, thereby both fixing the implant in place and preventing the blood vessel from collapsing. In these examples, the second section 104 can maintain the braided mesh 108 material so that the second section 104 can be folded as described above.

[0050] Figures 5A and 5B show a third section 106 that includes a stent 502 portion of the implant, although the first section 102 and / or the third section 106 can include the stent 502 portion. This will be described in more detail below with reference to FIGS. 6A-6C. Further, the shape and / or design of the stent 502 is not limited to the examples shown in FIGS. 5A and 5B, and these are merely illustrative. FIG. 5A shows a stent 502 having a series of peaks and valleys connected to each other, and FIG. 5B shows a stent 502 having a uniform pattern of interconnected shapes. The stent 502 can be a laser cut lattice design, a shaped wire design, a wire braid design, and the like.

[0051] Figures 5C and 5D show an exemplary attachment mechanism for connecting a braided mesh 108 section of the implant to a stent 502 section of the implant. As shown in FIG. 5C, the braided mesh 108 of the second section 104 can include, for example, a first plurality of looped ends 504. The laser cut stent 502 section can include a second plurality of looped ends 506. At least a portion of the first plurality of looped ends 504 can be interwoven with at least a portion of the second plurality of looped ends 506 to connect the braided mesh 108 to the stent 502.

[0052] In other examples, clip 550 can be used to connect braided mesh 108 to stent 502. This clip 550 mechanism is described in more detail in U.S. Patent No. 10,076,428, which is incorporated herein by reference as if fully set forth below. Clip 550 can be connected to the end of stent 502 and can include a central strut member 552 and an outer strut member 554. The central strut member 552 can be positioned on one side (one surface) of the braided mesh 108, while the outer strut member 554 can be positioned on the other side (the other surface) of the braided mesh 108. The attachment location 556 can be positioned where the central strut member 552 and the outer strut member 554 intersect. At this attachment location 556, the central strut member 552 can be permanently connected to the outer strut member 554 via one or more welds, soldered connections, chemical adhesives, etc. Once permanently connected, the stent 502 can be secured to the braided mesh 108.

[0053] Figures 6A - 6C are schematic cross-sectional views of an implanted flow diverter 100 having both a braided mesh 108 section and a stent 502 section, according to aspects of the present disclosure. As described above, the stent section 502 of the implant can be located in the first section 102 of the implant, in the third section 106 of the implant, or in both the first section 102 and the third section 106 of the implant. In Figure 6A, the stent 502 is positioned in both the first section 102 and the third section 106. The folding of the flow diverter 100 can still be facilitated by the second section 104 that includes the less rigid braided mesh 108. In Figure 6B, the first section 102 of the implant includes the stent 502. In Figure 6C, the third section 106 of the implant includes the stent 502.

[0054] FIG. 7 is a flow diagram showing a method 700 for implanting a foldable flow diverter according to an aspect of the present disclosure. The method steps of FIG. 7 can be implemented by any of the exemplary means described herein or by similar means, as will be appreciated. Referring to method 700 as outlined in FIG. 7, at step 705, a first section of the flow diverter can be deployed via a catheter such as a microcatheter. The first section can be delivered distally of the aneurysm neck through a blood vessel. At step 710, a second section of the flow diverter can be inverted to contact the second section with the inner lumen of the first section.

[0055] At step 715, the second section can be positioned such that the second section traverses the aneurysm neck. At step 720, the catheter can be moved (i.e., retracted) proximally of the aneurysm neck. Simultaneously with moving the catheter, a third portion of the flow diverter can be deployed via the catheter. At step 725, an overlapping section adjacent to the aneurysm neck can be formed that includes at least a portion of the first section, the second section, and the third section.

[0056] Method 700 can end after step 725. In other embodiments, additional steps according to the above-described embodiments can be performed. For example, the step of forming the overlapping section can reduce the porosity of the flow diverter adjacent to the overlapping section to about 50% to about 70%. In some examples, method 700 can include folding the flow diverter at the connection between the braided mesh section of the implant and the laser cut stent section of the implant.

[0057] The descriptions contained in this specification are examples of embodiments of the present invention and do not limit the scope of the present invention in any way. The present invention contemplates many variations and modifications of the implant, including alternative delivery methods, alternative braiding materials, alternative means for obtaining the desired stiffness / flexibility of the braiding material, additional structures attached to the implant (e.g., to assist in implant fixation, blood diversion, embolization, etc.), alternative predetermined braided shapes (e.g., one inversion, three inversions, four inversions, five or more inversions, radially asymmetric shapes, alternative segment shapes, etc.), alternative implant shapes, and the like. Modifications that are obvious to those skilled in the art in accordance with the teachings of this disclosure are intended to be within the scope of the following claims.

[0058] 〔Embodiment〕 (1) A flow diverter for blood vessels, comprising: a first tubular section defining an inner lumen; a third tubular section that can be disposed within the inner lumen; and a second tubular section disposed between the first tubular section and the third tubular section, wherein the flow diverter for blood vessels is foldable from a delivery configuration to an implanted configuration, in the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape, and in the implanted configuration, the second tubular section overlaps at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section. A flow diverter for blood vessels. (2) The flow diverter for blood vessels according to Embodiment 1, wherein the first tubular section, the third tubular section, and the second tubular section comprise a braided mesh having a porosity of about 80% to about 90%. (3) The flow diverter for blood vessels according to Embodiment 2, wherein the three-layer shape adjacent to the second tubular section has a porosity of about 50% to about 70%. (4) The vascular flow diverter according to Embodiment 1, wherein the second tubular section has a porosity different from that of the first tubular section and the third tubular section. (5) The first tubular section, the third tubular section, and the second tubular section each include a braided mesh, The vascular flow diverter according to Embodiment 1, wherein the braided mesh of the second tubular section has a braiding angle different from that of the braided meshes of the first tubular section and the third tubular section.

[0059] (6) The second tubular section has a first material thickness, The first tubular section and the third tubular section have a second material thickness, The vascular flow diverter according to Embodiment 1, wherein the first material thickness is smaller than the second material thickness. (7) The vascular flow diverter according to Embodiment 1, further including a first bending point disposed between the first tubular section and the second tubular section, and a second bending point disposed between the third tubular section and the second tubular section. (8) The vascular flow diverter according to Embodiment 1, wherein one of the first tubular section and the third tubular section includes a braided mesh, and the other of the third tubular section and the first tubular section includes a laser-cut stent. (9) The vascular flow diverter according to Embodiment 1, wherein the second tubular section includes an anti-thrombotic coating. (10) An implant that can be formed in a cylindrical shape and can be transitioned to an implanted shape, including a first section including a first outer layer, a second section including a second outer layer that can be folded so as to contact the first outer layer, and a third section including a third outer layer that can be folded so as to contact the second outer layer. When in the implanted shape, the implant comprises a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer. When in the implanted shape, the three-layer overlapping section is an implant disposed adjacent to the aneurysm neck.

[0060] (11) The implant according to Embodiment 10, wherein the first section, the third section, and the second section each comprise a braided mesh having a porosity of about 80% to about 90%. (12) The implant according to Embodiment 11, wherein when in the implanted shape, the three-layer overlapping section has a porosity of about 50% to about 70%. (13) The first section, the third section, and the second section each comprise a braided mesh. The implant according to Embodiment 10, wherein the braided mesh of the second section has a braiding angle different from that of the braided meshes of the first section and the third section. (14) The implant according to Embodiment 10, further comprising a first bending point disposed between the first section and the second section, and a second bending point disposed between the third section and the second section. (15) The implant according to Embodiment 10, wherein one of the first section and the third section comprises a braided mesh, and the other of the third section and the first section comprises a laser-cut stent.

[0061] (16) The second section comprises a braided mesh. The braided mesh of the second section comprises a first plurality of loop-shaped ends. The laser-cut stent comprises a second plurality of loop-shaped ends. The implant according to embodiment 15, wherein at least a portion of the first plurality of looped ends is intertwined with at least a portion of the second plurality of looped ends. (17) The implant according to embodiment 10, wherein the second section comprises an antithrombotic coating. (18) A method comprising: deploying, via a catheter, a first section of a flow diverter distally of an aneurysm neck through a blood vessel; inverting a second section of the flow diverter to bring the second section into contact with the inner lumen of the first section; positioning the second section of the flow diverter such that the second section traverses the aneurysm neck; moving the catheter proximally of the aneurysm neck and simultaneously deploying, via the catheter, a third section of the flow diverter; forming an overlapping section of the flow diverter adjacent to the aneurysm neck, the overlapping section comprising at least a portion of the first section, the second section, and the third section. (19) The first section, the third section, and the second section comprise a braided mesh having a porosity of about 80% to about 90%, The method according to embodiment 18, wherein the step of forming the overlapping section reduces the porosity of the flow diverter adjacent to the overlapping section to about 50% to about 70%. (20) At least one of the first section or the third section comprises a laser-cut stent, The second section comprises a braided mesh connected to the laser-cut stent, The method further comprises: folding the flow diverter at the connection between the braided mesh and the laser-cut stent.

Claims

**Claim 1** A flow diverter for blood vessels, comprising: a first tubular section defining an inner lumen; a third tubular section that can be disposed within the inner lumen; a second tubular section disposed between the first tubular section and the third tubular section; the flow diverter for blood vessels is foldable from a delivery configuration to an implanted configuration; in the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape; in the implanted configuration, the second tubular section overlaps at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section; the first tubular section, the third tubular section, and the second tubular section are provided with a braided mesh having a porosity of about 80% to about 90%; the three-layer shape adjacent to the second tubular section has a porosity of about 50% to about 70%, a flow diverter for blood vessels. **Claim 2** A flow diverter for blood vessels, comprising: a first tubular section defining an inner lumen; a third tubular section that can be disposed within the inner lumen; a second tubular section disposed between the first tubular section and the third tubular section; the flow diverter for blood vessels is foldable from a delivery configuration to an implanted configuration; in the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape; in the implanted configuration, the second tubular section overlaps at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section; the second tubular section has a porosity different from that of the first tubular section and the third tubular section, a flow diverter for blood vessels. **Claim 3** A flow diverter for blood vessels, comprising: a first tubular section defining an inner lumen; a third tubular section that can be disposed within the inner lumen; a second tubular section disposed between the first tubular section and the third tubular section; the flow diverter for blood vessels is foldable from a delivery configuration to an implanted configuration; In the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape, In the embedding configuration, the second tubular section overlaps at least a part of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section, The first tubular section, the third tubular section, and the second tubular section each include a braided mesh, The braided mesh of the second tubular section has a braiding angle different from that of the braided meshes of the first tubular section and the third tubular section, a flow diverter for blood vessels. **Claim 4**: A flow diverter for blood vessels, A first tubular section defining an inner lumen, A third tubular section that can be disposed within the inner lumen, A second tubular section disposed between the first tubular section and the third tubular section, and The flow diverter for blood vessels is foldable from a delivery configuration to an embedding configuration, In the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape, In the embedding configuration, the second tubular section overlaps at least a part of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section, The second tubular section has a first material thickness, The first tubular section and the third tubular section have a second material thickness, The first material thickness is smaller than the second material thickness, a flow diverter for blood vessels. **Claim 5** A first bending point disposed between the first tubular section and the second tubular section, A second bending point disposed between the third tubular section and the second tubular section, and further including the flow diverter for blood vessels according to claim 1. **Claim 6**: A flow diverter for blood vessels, A first tubular section defining an inner lumen, A third tubular section that can be disposed within the inner lumen, A second tubular section disposed between the first tubular section and the third tubular section, and The vascular flow diverter is foldable from a delivery configuration to an implanted configuration, In the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape, In the implanted configuration, the second tubular section overlaps at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section, One of the first tubular section and the third tubular section comprises a braided mesh, The other of the third tubular section and the first tubular section comprises a laser-cut stent, a vascular flow diverter. **Claim 7** A vascular flow diverter, A first tubular section defining an inner lumen, A third tubular section that can be disposed within the inner lumen, A second tubular section disposed between the first tubular section and the third tubular section, and comprising, The vascular flow diverter is foldable from a delivery configuration to an implanted configuration, In the delivery configuration, the first tubular section, the second tubular section, and the third tubular section define a single-layer cylindrical shape, In the implanted configuration, the second tubular section overlaps at least a portion of the first tubular section and the third tubular section, thereby forming a three-layer shape adjacent to the second tubular section, The second tubular section comprises an antithrombotic coating, a vascular flow diverter. **Claim 8** An implant that can be formed in a cylindrical shape and transitioned to an implanted shape, A first section including a first outer layer, A second section including a second outer layer that can be folded to contact the first outer layer, A third section including a third outer layer that can be folded to contact the second outer layer, and comprising, When in the implanted shape, the implant comprises a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer, When in the implanted shape, the three-layer overlapping section is disposed adjacent to the aneurysm neck, The first section, the third section, and the second section comprise a braided mesh having a porosity of about 80% to about 90%, An implant having a porosity of about 50% to about 70% when in the implanted shape. **Claim 9**: An implant that can be formed in a cylindrical shape and can be transitioned to an implanted shape, comprising a first section including a first outer layer, a second section including a second outer layer that can be folded so as to contact the first outer layer, and a third section including a third outer layer that can be folded so as to contact the second outer layer, wherein when in the implanted shape, the implant comprises a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer, wherein when in the implanted shape, the three-layer overlapping section is disposed adjacent to the aneurysm neck, wherein each of the first section, the third section, and the second section comprises a braided mesh, and wherein the braided mesh of the second section has a braiding angle different from that of the braided meshes of the first section and the third section. **Claim 10** further comprising a first bending point disposed between the first section and the second section, and a second bending point disposed between the third section and the second section. **Claim 11**: An implant that can be formed in a cylindrical shape and can be transitioned to an implanted shape, comprising a first section including a first outer layer, a second section including a second outer layer that can be folded so as to contact the first outer layer, and a third section including a third outer layer that can be folded so as to contact the second outer layer, wherein when in the implanted shape, the implant comprises a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer, wherein when in the implanted shape, the three-layer overlapping section is disposed adjacent to the aneurysm neck, wherein one of the first section and the third section comprises a braided mesh, and wherein the other of the third section and the first section comprises a laser-cut stent. **Claim 12** wherein the second section comprises a braided mesh, wherein the braided mesh of the second section comprises a first plurality of loop-shaped ends, and wherein the laser-cut stent comprises a second plurality of loop-shaped ends. The implant according to claim 11, wherein at least a portion of the first plurality of loop-shaped ends is interwoven with at least a portion of the second plurality of loop-shaped ends. **Claim 13**: An implant that can be formed in a cylindrical shape and can be transitioned to an implanted shape, comprising a first section including a first outer layer, a second section including a second outer layer that can be folded so as to contact the first outer layer, and a third section including a third outer layer that can be folded so as to contact the second outer layer. When in the implanted shape, the implant comprises a three-layer overlapping section including the first outer layer, the second outer layer, and the third outer layer. When in the implanted shape, the three-layer overlapping section is disposed proximate to the aneurysm neck. The second section comprises an anti-thrombotic coating. The implant.

Images