Anti-movement stent with double-walled flange

Abstract

The stent includes a tubular body having opposing first and second open ends and a lumen extending between them. The stent includes a first anchor member positioned adjacent to the first open end and a second anchor member positioned adjacent to the second open end, the first and second anchor members spaced apart from each other by a saddle region of the tubular body, each extending radially outward from the tubular body, and each having an outer diameter greater than the outer diameter of the saddle region positioned between the first and second anchor members. Each of the first and second anchor members includes an outer wall and an inner wall spaced apart from the outer wall, and the tubular body is defined by only a single wall.

Description

Technical Field

[0004] , , , , , ,

[0003]

[0001] The present invention relates to a device, method, and system for implanting a stent. More particularly, the present invention relates to an implantable stent for forming an anastomosis.

Background Art

[0002] An intraluminal prosthesis is a medical device used for treating the lumen of the body. As a type of intraluminal prosthesis used for the repair and / or treatment of various diseases of the internal tubes of the body, there is a stent. A stent is a generally elongated tubular device formed from a biocompatible material, which is useful for opening and supporting various body lumens and / or forming a conduit between body lumens. For example, stents can be used in various body lumens such as the vascular system, urogenital tract, gastrointestinal tract, esophagus, trachea / bronchi, and bile duct, as well as various other applications in the body.

[0003] A lumen apposing metal stent (LAMS) is also used for discharging pseudocysts, pancreatic fluid accumulations, and for providing a direct drainage path for the bile duct and gallbladder. LAMS can also be used at other sites where it is desirable to form a conduit that penetrates the wall between two tubular structures. Therefore, there is still a need to provide an alternative stent structure that provides such a conduit.

Summary of the Invention

[0004] This disclosure provides a medical device configuration, materials, manufacturing method, and alternative uses. An exemplary stent is a tubular body formed from one or more woven wires, the tubular body having opposing first open ends and second open ends, and a lumen extending between the first and second open ends, the tubular body defining a longitudinal axis and a length extending between the first and second open ends, and a first anchor member positioned adjacent to the first open end and a second anchor member positioned adjacent to the second open end, the first and second anchor members being tubular The tubular body comprises a first anchor member and a second anchor member, each of which is spaced apart from each other by a saddle region of the main body, each extending radially outward from the saddle region, and each of which has an outer diameter greater than the outer diameter of the saddle region positioned between the first and second anchor members, wherein each of the first and second anchor members includes an outer wall and an inner wall spaced apart from the outer wall, and the tubular body is defined by only a single wall.

[0005] Alternatively or additionally in the above embodiment, the outer walls of each of the first and second anchor members are interwoven with the tubular body. Alternatively or additionally in the above embodiment, the inner wall defines an internal space within each of the first and second anchor members that communicates with the lumen of the tubular body.

[0006] Alternatively or additionally in the above embodiment, the outer wall is attached to the inner wall only at the bases of the first and second anchor members, the bases of which are adjacent to the tubular body. Alternatively or additionally in the above embodiment, the first and second anchor members are formed as separate elements attached to the tubular body, such that the tubular body extends across the bases of each of the first and second anchor members, and the inner walls define an internal space separated from the lumen by one or more interwoven wires forming the tubular body.

[0007] Alternatively or additionally in the above embodiment, the tubular body includes a first end region extending between a first open end and a first anchor member, and a second end region extending between a second open end and a second anchor member, wherein the outer diameters of the first and second anchor members are greater than the outer diameters of the first and second end regions.

[0008] In the above embodiments, alternatively or additionally, the outer diameters of the saddle region, the first end region, and the second end region are all substantially the same. Alternatively or additionally in the above embodiment, the first and second anchor members are less flexible than the tubular body.

[0009] In the above embodiment, alternatively or additionally, the stent further comprises a cover extending over and covering the tubular body, while the entirety of each of the first and second anchor members is not provided with a cover.

[0010] In the above embodiment, alternatively or additionally, the stent further comprises a cover extending over the entire tubular body and over the inner walls of each of the first and second anchor members. In the above embodiment, alternatively or additionally, the outer walls of the first anchor member and the second anchor member are not provided with covers.

[0011] Alternatively or additionally in the above embodiment, the first and second anchor members extend perpendicular to the longitudinal axis. Another exemplary stent is a tubular body formed from one or more woven wires, the tubular body having opposing first open ends and second open ends, and a lumen extending between the first and second open ends, the tubular body defining a longitudinal axis, the tubular body and first and second anchor members spaced apart in the longitudinal direction, each of the first and second anchor members having a base adjacent to the tubular body and extending radially outward to a free end, the first Each of the first and second anchor members has an outer diameter larger than the outer diameter of the tubular body positioned between the first and second anchor members, and each of the first and second anchor members defines a double-wall flange including a substantially U-shaped outer wall and a substantially U-shaped inner wall positioned at a distance from the outer wall, with the inner wall fixed to the outer wall only at its base such that the outermost free end of the inner wall in the radial direction can move freely within the outer wall.

[0012] Alternatively or additionally in the above embodiment, at least one of the outer and inner walls of each of the first and second anchor members is interwoven with the tubular body. Alternatively or additionally in the above embodiment, the inner wall defines an internal space within each of the first and second anchor members that communicates with the lumen of the tubular body.

[0013] Alternatively or additionally in the above embodiment, the first and second anchor members are formed as separate elements attached to the tubular body, such that the tubular body extends across the bases of each of the first and second anchor members, and the inner walls define an internal space separated from the lumen by one or more interwoven wires forming the tubular body.

[0014] Alternatively or additionally in the above embodiment, the tubular body includes a first end region extending between a first open end and a first anchor member, and a second end region extending between a second open end and a second anchor member, wherein the outer diameters of the first and second anchor members are greater than the outer diameters of the first and second end regions, and the outer diameters of the tubular body between the first and second anchor members, the first end region, and the second end region are all substantially the same.

[0015] In the above embodiment, alternatively or additionally, the stent further comprises a cover extending over and covering the tubular body, and the inner and outer walls of the first and second anchor members, respectively, are not provided with covers.

[0016] Alternatively or additionally in the above embodiment, the stent includes a cover that extends over the entire tubular body and over the inner walls of each of the first and second anchor members, while the outer walls of each of the first and second anchor members are not provided with a cover.

[0017] An exemplary method for forming an anastomosis between a first and a second biological organ, spaced apart from each other, is to implant a stent through the first tissue wall of the first biological organ and the second tissue wall of the second biological organ, wherein the first open end of the stent is positioned within the first biological organ and the second open end of the stent is positioned within the second biological organ, the stent comprising a tubular body formed from one or more interwoven wires, the tubular body defining a lumen extending between the first and second open ends, and the stent comprising a first anchor member and a second anchor member longitudinally spaced apart and extending radially outward from the tubular body, the first and Each of the second anchor members has an outer diameter larger than the outer diameter of a saddle region extending between the first and second anchor members, and each of the first and second anchor members includes an outer wall and an inner wall spaced apart from the outer wall, and the tubular body is defined by only a single wall, and the stent is embedded such that the first tissue wall of the first biological organ and the second tissue wall of the second biological organ are positioned in the saddle region, the first anchor member is positioned in the first biological organ and the second anchor member is positioned in the second biological organ, and the stent is embedded such that fluids and particles are discharged from the first biological organ into the second biological organ through the lumen of the stent.

[0018] The above summary of some embodiments is not intended to describe each disclosed embodiment or all implementations of this disclosure. The following drawings and “Modes for Carrying Out the Invention” illustrate some of these embodiments more specifically. [Brief explanation of the drawing]

[0019] In drawings that are not necessarily drawn to a consistent scale, the same reference numeral may describe similar components in different drawings. Drawings typically illustrate various embodiments described herein, not as limitations, but as examples. [Figure 1A-1C] Figure 1A-1C shows the gastrojejunal anastomosis procedure. [Figure 2]FIG. 2 is a side cross-sectional view of a prior art stent. [Figure 3] FIG. 3 is a side cross-sectional view of an exemplary tubular stent implanted across first and second biological organs according to an embodiment of the present disclosure. [Figure 4A] FIG. 4A is a side cross-sectional view of the tubular stent of FIG. 3 in which individual stent wires are not shown for clarity. [Figure 4B] FIG. 4B shows an enlarged view of region 4B of the tubular stent shown in FIG. 4A. [Figure 5] FIG. 5 is a side cross-sectional view of another exemplary tubular stent according to another embodiment of the present disclosure. [Figure 6] FIG. 6 is a side cross-sectional view of a further exemplary tubular stent according to a further embodiment of the present disclosure. **DETAILED DESCRIPTION OF THE INVENTION**

[0020] The present disclosure is capable of following various modifications and alternative forms, and details thereof are shown in the drawings by way of example and will be described in detail. However, it should be understood that the intention is not to limit the present invention to the specific embodiments described. On the contrary, all modifications, equivalents, and alternative forms within the spirit and scope of the present disclosure are intended to be covered.

[0021] For the terms defined below, the following definitions shall apply unless a different definition is provided in either the claims or the specification. All numerical values are assumed to be modified by the term "about" whether or not explicitly stated. The term "about" generally refers to a range of numerical values that a person skilled in the art would consider to be equivalent to the recited value (e.g., having the same function or result). In many instances, the term "about" includes a plurality of numerical values that are rounded to the nearest significant digit.

[0022] The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). When used herein and in the appended claims, the singular forms “a,” “an,” and “the” refer to multiple subjects unless the context clearly indicates otherwise. When used herein and in the appended claims, the term “or” is generally used to include “and / or” unless the context clearly indicates otherwise.

[0023] Please note that references to “certain embodiments,” “several embodiments,” “other embodiments,” etc., in this specification indicate that the embodiments described may include one or more specific features, structures, and / or characteristics. However, such descriptions do not necessarily mean that all embodiments include specific features, structures, and / or characteristics. Furthermore, when specific features, structures, and / or characteristics are described in relation to an embodiment, please understand that such features, structures, and / or characteristics may also be used in relation to other embodiments, whether explicitly described or not, unless explicitly stated otherwise.

[0024] The following detailed description should be read with reference to the drawings, where similar structures in different drawings are numbered the same. The drawings are not necessarily to a specific scale and illustrate exemplary embodiments; they are not intended to limit the scope of this disclosure.

[0025] Lumen-apposing metal stents (LAMS) can be used to create and maintain an alternative flow path between two body lumens. For example, LAMS can be used in gastrojejunal anastomoses or similar anastomoses that bypass the proximal bowel. LAMS are constructed to penetrate the tissue wall of an organ and function as a conduit between two biological organs. LAMS may also be used in endoscopic metabolic therapy or natural orifice transluminal endoscopic surgery (NOTES) procedures to form an anastomosis (gastrojejunal anastomosis) between the stomach and the jejunum, allowing the flow of food particles and liquids from the stomach to the lower gastrointestinal tract by bypassing the pylorus and duodenum. This procedure can be used as a less invasive treatment for obesity and type 2 diabetes, which are generally treated with surgical bypasses using the Roux-en-Y method.

[0026] The gastrojejunal anastomosis procedure is illustrated in Figures 1A and 1C. In Figure 1A, plug 5 is placed between the stomach 10 and the duodenum 8 to close the pylorus. An anastomosis is formed between another region of the stomach 10 and the jejunum 17 using a LAMS device 100. As shown in Figure 1B, food particles 20 are blocked from passing from the stomach 10 through the pylorus to the duodenum 8 and the upper 1.5 m region of the small intestine (where most fats and nutrients are digested). Instead, as shown in Figure 1C, food particles 20 enter the jejunum 17 and the lower region of the small intestine directly from the stomach 10 through the LAMS device 100. The LAMS device 100 can be positioned to bypass a desired region of the small intestine. For example, the first 0.5 to 2.0 m of the small intestine may be bypassed. In one example, the first 1.5 m of the small intestine may be bypassed.

[0027] Based on initial preclinical studies, a migration rate of 33% was observed in an animal model using the conventional stent 30 shown in Figure 2. Figure 2 is a side cross-sectional view of the stent, and the individual wires constituting the stent are not shown in order to more clearly illustrate the structure of the anchor member. The stent configuration includes a conventional stent 30 made of nitinol and fully covered with silicone, with a first anchor member 32 and a second anchor member 34 positioned on either side of a saddle region 36 that enables the formation of an anastomosis. The first anchor member 32 and the second anchor member 34 are each formed with a single wall 38. The single wall 38 defining each flange is typically formed from the wires that make up the rest of the stent. The silicone cover on the stent is configured to prevent leakage of food particles and liquids during anastomosis formation. Stent migration was sometimes observed in the animal model during anastomosis formation. The indicative duration of stent placement in the metabolic space between the stomach and small intestine is extending from a maximum of 60 days to 6-12 months. This indicates a growing need for LAMS with more robust migration-preventing features.

[0028] Figure 3 shows a stent 100 comprising a first anchor member 152 and a second anchor member 154 configured to maintain tissue juxtaposition, and a body or saddle region 118 having material properties that apply radial force enabling the formation of an anastomosis, while also allowing the opposing tissues to bend and move independently. The stent 100 is shown in a position to provide a gastrojejunal anastomosis, with the stent extending between the stomach 10 and the jejunum 17, spanning the inter-organ space 15 between them, and in the saddle region 118, the tissue walls 12 of the stomach 10 and 18 of the jejunum 17 are sandwiched between the first anchor member 152 and the second anchor member 154. Note that the stent 100 may be used to bridge the walls of any anatomical structure. The stent 100 may have a tubular body 110 having a first open end 112 and a second open end 114, and a lumen extending between the first open end 112 and the second open end 114. The tubular body 110 may be formed from one or more woven wires 115 that may be woven, braided, wound, woven, and combinations thereof to form the tubular body 110. The stent 100 may include multiple wires 115 of metallic material such as nitinol or a nitinol-containing material, or other nickel-titanium alloys. In some cases, the wires 115 may have a diameter of, for example, about 0.011 inches (about 0.28 mm). The number and diameter of the wires 115 shown in Figure 3 are not limiting and may be the same or different, and a different number of wires 115 or wires of a different diameter may be suitably used. Preferably, an even number of wires 115, for example, about 10 to about 36 wires 115, can be used.

[0029] Preferably, the wire 115 is formed from any suitable embeddable material, including but not limited to nitinol, stainless steel, cobalt-based alloys such as Elgiloy®, platinum, gold, titanium, tantalum, niobium, polymer materials, and combinations thereof. Useful and non-limiting examples of polymer stent materials include poly(L-lactide) (PLLA), poly(D,L-lactide) (PLA), poly(glycolide) (PGA), poly(L-lactide-co-D,L-lactide) (PLLA / PLA), poly(L-lactide-co-glycolide) (PLLA / PGA), poly(D,L-lactide-co-glycolide) (PLA / PGA), poly(glycolide-co-trimethylene carbonate) (PGA / PTMC), polydioxanone (PDS), polycaprolactone (PCL), polyhydroxybutyrate (PHBT), poly(phosphazene)poly(D,L-lactide-co-caprolactone)PLA / PCL), poly(glycolide-co-caprolactone) (PGA / PCL), and poly(phosphate ester). The wire made of polymer material may also contain radiopaque materials, such as metal-based powders, particles, or pastes, which can be incorporated into the polymer material. For example, the radiopaque material may be blended with the polymer composition on which the polymer wire is formed and then shaped into the stent 100 as described herein. Alternatively, the radiopaque material may be coated onto the surface of the metal or polymer wire 115 of the stent 100. In either case, a variety of radiopaque materials and their salts and derivatives can be used, for example, but are not limited to, bismuth, barium, and salts of barium sulfate, tantalum, tungsten, gold, platinum, and titanium. Additional useful radiopaque materials are disclosed in U.S. Patent No. 6,626,936, which is incorporated herein by reference. Metal complexes that are useful as radiopaque materials are also conceivable. The stent can be selectively radiopaque in a desired region along the wire, or completely radiopaque.

[0030] In some cases, the wire 115 has a composite structure having an inner core of tantalum, gold, platinum, tungsten, iridium, or a combination thereof, and an outer member or layer of nitinol, providing a composite wire for improved radiopaqueness and visibility. In one example, the inner core is platinum and the outer layer is nitinol. The platinum inner core accounts for at least about 10% of the wire 115 based on the proportion of the total cross-section. Furthermore, nitinol that has not been treated for shape memory, such as by heating, shaping, and cooling its martensite and austenite phases, is also useful as an outer layer. Further details of such composite wires are disclosed in U.S. Patent No. 7,101,392, the contents of which are incorporated herein by reference. The wire 115 is formed from nitinol or from a composite wire having a platinum core and a nitinol outer layer. Furthermore, when required in welding processes such as MIG welding, the welding material to be filled can also be formed from nitinol, stainless steel, cobalt-based alloys such as Elgiloy, platinum, gold, titanium, tantalum, niobium, and combinations thereof.

[0031] The tubular body 110 defines a longitudinally extending lumen 116 between a first open end 112 and a second open end 114. The first anchor member 152 may be positioned adjacent to the first open end 112, and the second anchor member 154 may be positioned adjacent to the second open end 114, with the first and second anchor members 152 and 154 spaced longitudinally apart by a saddle region 118. Both the first and second anchor members 152 and 154 may be self-expandable from a compression delivery configuration in which the anchor members 152 and 154 extend substantially parallel to the longitudinal axis xx. In another example, the first and second anchor members 152 and 154 are balloon-expandable. Each of the first and second anchor members 152 and 154 may extend radially outward from a base 151 adjacent to the tubular body 110 to a free end 156, forming a flange. In the example shown in Figure 3, the first and second anchor members 152 and 154 are symmetrical and the same size, extending continuously and circumferentially around the tubular body 110. In other embodiments, the first anchor member 152 and the second anchor member 154 may have different sizes, and may differ in longitudinal width and radial length. The first and second anchor members 152 and 154 may extend radially outward from the tubular body 110 substantially perpendicular to the longitudinal axis xx of the stent 100. Each of the first anchor member 152 and the second anchor member 154 may have an outer diameter larger than the outer diameter of the saddle region 118 located between the first anchor member 152 and the second anchor member 154. The first anchor member 152 may have an outer diameter larger than the outer diameter of the first end region 111 of the tubular body 110 extending between the first open end 112 and the first anchor member 152, and the second anchor member 154 may have an outer diameter larger than the outer diameter of the second end region 113 of the tubular body 110 extending between the second open end 114 and the second anchor member 154. The outer diameters of both the first and second anchor members 152 and 154 may be larger than the outer diameters of both the first and second end regions 111 and 113. In some examples, the saddle region 118, the first end region 111, and the second end region 113 may all have substantially the same outer diameter.

[0032] The first and / or second anchor members 152, 154 may be formed from a portion of the wire 115 that forms the tubular body 110. In other embodiments, the first and / or second anchor members 152, 154 may be formed separately from the tubular body 110 and attached to the outer surface of the tubular body, for example, by welding or using an adhesive. The first and / or second anchor members 152, 154 may have lower flexibility than the tubular body 110. If the first anchor member 152 and / or the second anchor member 154 are formed from the same wire 115 as the tubular body 110, the flexibility of the anchor members 152, 154 can be made lower than that of the tubular body 110 by making the weave pattern, braid pattern, or knit pattern of the first anchor member 152 and / or the second anchor member 154 different (e.g., denser) from the weave pattern, braid pattern, or knit pattern of the tubular body 110. Alternatively, if the first anchor member 152 and / or the second anchor member 154 are formed separately, they may be formed from wires having relatively low flexibility, or they may have lower flexibility than the tubular body 110 by including a relatively large number of wires in the pattern. Whether the first anchor member 152 and / or the second anchor member 154 are formed from the same number of wires as the tubular body 110 or are formed separately and attached to the tubular body 110, the bases 151 of the first anchor member 152 and the second anchor member 154 are fixed relative to the saddle region 118, and the tissue walls 18,12 can be held side by side between the first anchor member 152 and the second anchor member 154.

[0033] The stent 100 may include, for example, a covering 160 that extends along the tubular body 110, both inside and / or outside the tubular body 110. In some examples, the covering 160 extends over the entire outer surface of the stent 100, including the tubular body 110 and the first and second anchor members 152, 154. In other examples, the covering 160 extends over the entire inner surface of the stent 100, including the tubular body 110 and the first and second anchor members 152, 154. The cover 160 may completely cover the entire length of the stent 100 to form a fully covered stent, in which all of the gaps defined by the woven wires (e.g., gaps in a braid or weave pattern) are covered by the cover 160, thereby preventing tissue in-growth of the stent 100 into the lumen 116 and fluid leakage from the lumen 116 of the stent 100 into the inter-organ space 15. In other examples, the cover 160 may cover only a portion of the length of the stent 100 to form a partially covered stent, in which some of the gaps defined by the woven wires (e.g., gaps in a braid or weave pattern) remain uncovered, allowing tissue in-growth in the uncovered portion of the stent 100. For example, the cover 160 may be provided to cover only the saddle region 118 of the stent 100, which is positioned in the inter-organ space 15. The cover 160 may be provided on the inner or outer surface of the saddle region 118. In some examples, the cover 160 may be a sleeve-like structure having a substantially continuous wall surface, such as a silicone sleeve. The cover 160 is not provided on the entirety of the first anchor member 152 and / or the second anchor member 154, and the first end region 111 and / or the second end region 113. This allows for tissue proliferation into the first anchor member 152 and / or the second anchor member 154, which can contribute to preventing the stent 100 from moving. The cover 160 may be expandable and contractible along with any expansion and contraction of the stent 100.The cover 160 on the outer surface of the stent can help grip the tissue walls 18,12 and protect the tissue walls 18,12 from any damage that may occur when the multiple wires forming the stent 100 come into contact with the tissue walls 18,12.

[0034] In some examples, the stent 100 can be spray-coated or immersion-coated with a polymer cover 160 by spraying a silicone or other polymer solution onto the stent 100, or by immersing the stent 100 in a silicone or other polymer solution to form the cover 160. In other examples, a polymer sheet or polymer tube may be placed around or inside the stent 100 to form the cover 160. The cover 160 may be provided on the outer or inner surface of the stent 100, or on both the inner and outer surfaces of the stent 100, thereby embedding the stent 100 in the polymer material. The cover 160 may be a polymer cover such as a polytetrafluoroethylene (PTFE) cover or a silicone cover, but other covers, particularly elastomer polymers, may be used. Non-limiting examples of useful polymer materials include polyester, polypropylene, polyethylene, polyurethane, polynaphthalene, polytetrafluoroethylene, stretched polytetrafluoroethylene, silicone, and combinations and copolymers thereof.

[0035] The stent 100 is configured to continuously flex and move in response to the movement of the tissue walls 12 and 18, thereby reducing the force acting on individual anchor members and reducing the rate of stent 100 migration. Such a stent configuration may be used not only in metabolic procedures but also in other applications and internal body sites where migration is a concern.

[0036] Figure 4A shows a longitudinal section of the stent 100 of Figure 3, in which the individual wires constituting the stent are not shown in order to clearly illustrate the double-wall structure of the first anchor member 152 and the second anchor member 154 positioned on either side of the saddle region 118. Figure 4B shows an enlarged view of a portion of the second anchor member 154 of Figure 4A. The double-wall structure may include an outer wall 158 and an inner wall 159 spaced apart from the outer wall 158 by a first internal space 153. In some cases, the outer wall 158 may be a substantially U-shaped wall extending circumferentially around the stent 100, with the first and second ends of the outer wall 158 located at the bases 151 of the corresponding anchor members 152,154, and the arcuate portion of the wall located at the outermost radial extension or free end of the outer wall 158. Therefore, the outer wall 158 may extend outward from the tubular body 110 at the base 151 by a distance (for example, the radially extending distance of the outer wall 158), and then fold back toward the tubular body 110 and extend inward to the tubular body 110. Similarly, the inner wall 159 may be a substantially U-shaped wall extending circumferentially around the stent 100, with the first and second ends of the inner wall 159 located at the base 151 of the corresponding anchor members 152, 154, and the arcuate portion of the wall located at the outermost radially extending portion or free end of the inner wall 159. Therefore, the inner wall 159 may extend outward from the tubular body 110 at the base 151 by a distance (for example, the radially extending distance of the inner wall 159), and then fold back toward the tubular body 110 and extend inward to the tubular body 110. The outermost extension or free end of the outer wall 158 may be larger than the outermost extension or free end of the inner wall 159, and a radially extending gap is formed between them. In some cases, the internal space 153 may be a substantially U-shaped internal space that extends circumferentially around the stent 100 and creates a gap between the outer surface of the inner wall 159 and the inner surface of the outer wall 158.

[0037] The inner wall 159 may be woven with the tubular body 110 such that the inner wall 159 of the tubular body 110 and the first and second anchor members 152 and 154 form a single monolithic structure. In other words, the multiple woven wires forming the tubular body 110 may extend continuously from the tubular body 110 to form the inner wall 159 of the first anchor member 152 and / or the second anchor member 154.

[0038] Alternatively or additionally, the outer wall 158 may be woven with the tubular body 110 such that the entire outer surface of the stent 100, including the tubular body 110 and the respective outer walls 158 of the first and second anchor members 152 and 154, is a single monolithic structure. In other words, the multiple woven wires constituting the tubular body 110 may extend continuously from the tubular body 110 to form the outer walls 158 of the first anchor member 152 and / or the second anchor member 154.

[0039] In some examples, the woven wires 115 may extend continuously from a first open end 112 to a second open end 114, such that the woven wires 115 extend continuously through a first end region 111, a saddle region 118, and a second end region 113. The woven wires 115 may be divided into a first wire group and a second wire group in the first anchor member 152, with the first wire group forming only the outer wall 158 of the first anchor member 152 and the second wire group forming only the inner wall 159 of the first anchor member 152. In other words, a first group of the multiple interwoven wires 115 may extend from the first end region 111 to form the outer wall 158 of the first anchor member 152, and then return to form the saddle region 118, and a second group of the multiple interwoven wires 115 may extend from the first end region 111 to form the inner wall 159 of the first anchor member 152, and then return to form the saddle region 118. The first group of wires forming the outer wall 158 is different from the second group of wires forming the inner wall 159, and therefore, the wires used to form the outer wall 158 of the first anchor member 152 are not used to form the inner wall 159 of the first anchor member 152.

[0040] Similarly, the multiple woven wires 115 may be divided into a first wire group and a second wire group in the second anchor member 154, with the first wire group forming only the outer wall 158 of the second anchor member 154, and the second wire group forming only the inner wall 159 of the second anchor member 154. In other words, the first wire group of the multiple woven wires 115 may extend from the second end region 113 to form the outer wall 158 of the second anchor member 154, and then return to form the saddle region 118, and the second wire group of the multiple woven wires 115 may extend from the second end region 113 to form the inner wall 159 of the second anchor member 154, and then return to form the saddle region 118. The first group of wires forming the outer wall 158 is different from the second group of wires forming the inner wall 159. Therefore, the wires used to form the outer wall 158 of the second anchor member 154 are not used to form the inner wall 159 of the second anchor member 154.

[0041] The first group of wires forming the outer wall 158 of the first anchor member 152 may be the same as or different from the first group of wires forming the outer wall 158 of the second anchor member 154. Similarly, the second group of wires forming the inner wall 159 of the first anchor member 152 may be the same as or different from the second group of wires forming the inner wall 159 of the second anchor member 154.

[0042] Therefore, the inner wall 159 and outer wall 158 of the first and second anchor members 152 and 154 may be formed from only a portion of the multiple woven wires 115 that form the saddle region 118, the first end region 111, and / or the second end region 113 of the stent 100.

[0043] In other examples, the inner wall 159 and / or outer wall 158 may be formed separately from the tubular wall 110 and then attached to the tubular wall 110. For example, the inner wall 159 may be formed integrally with the multiple interwoven wires that form the tubular body 110, and then the outer wall 158 may be attached to the outer circumference of the inner wall 159.

[0044] The inner wall 159 may be fixed to the outer wall 158 only at the bases 151 of the first and second anchor members 152, 154, the bases 151 adjacent to the tubular body 110. The remaining portion of the inner wall 159, including the free end 180, is free to move within the outer wall 158 (floats freely). The radially outer portions of the outer wall 158 and the inner wall 159 can move independently of each other. For example, the radially outer portion of the outer wall 158 of one of the first anchor member 152 and / or the second anchor member 154 (e.g., the radially outermost arc-shaped portion of the outer wall 158) can bend toward the first open end 112 or the second open end 114 of the stent 100 without bending the corresponding inner wall 159 of the same anchor member 152, 154.

[0045] In some examples, as shown in Figure 4B, the inner wall 159 may be connected to the outer wall 158 by a connecting region 157 of the tubular body 110. The connecting region 157 may extend substantially parallel to the longitudinal axis. The inner wall 159 defines a second internal space 155 within the interior of the inner wall 159. In some examples, the second internal space 155 is continuous with the lumen 116 of the tubular body 110.

[0046] If the cover 160 is present on the tubular body 110, the cover may extend to cover both the outer wall 158 and inner wall 159 of the first and second anchor members 152 and 154, respectively. In other embodiments, the outer wall 158 of the first and second anchor members 152 and 154 may not be covered, and the inner wall 159 of the first and second anchor members 152 and 154 may be covered by the cover 160. The inner wall 159 may be covered with a polymer sleeve or a silicone sleeve. Therefore, in some cases, the cover 160 may extend along the entire length of the stent 100, covering the first end region 111, the inner wall 159 of the first anchor member 152, the saddle region 118, the inner wall 159 of the second anchor member 154, and the second end region 113, while the outer walls 158 of the first and second anchor members 152 and 154, respectively, may remain uncovered or not have the cover 160. This allows the outer wall 158 to provide intracellular growth into the gaps formed between the multiple interwoven wires forming the outer wall 158 to prevent movement, while the inner wall 159 may be covered to prevent intracellular growth into the lumen 116 and provide a fluid-tight conduit through the lumen 116. In other cases, the outer wall 158 may be covered with the cover 160, and the inner wall 159 may not have a cover.

[0047] The double-wall structure of the first and second anchor members 152, 154 may be in contrast to a tubular body 110 that can be defined by a single wall 117 alone. In other examples, at least a portion of the tubular body 110 may be formed by a double-wall structure. For example, a saddle region 118 may have a double-wall structure in which a first wall formed of multiple interwoven wires radially surrounds a second wall formed of multiple interwoven wires. The first wall, i.e., the outer wall, of the double-wall structured saddle region 118 may be formed of the same or different multiple wires as the second wall, i.e., the inner wall, of the double-wall structured saddle region 118.

[0048] The outer walls 158 of the first and second anchor members 152 and 154 may be interwoven with the tubular body 110. For example, a plurality of interwoven wires 115 forming the tubular body 110 may extend radially outward to form the outer walls 158 of the first and second anchor members 152 and 154, thereby allowing the entire tubular body 110 and the outer walls 158 of the first and second anchor members 152 and 154 to be continuously formed from the same plurality of wires 115.

[0049] Additionally or alternatively, the inner walls 159 of each of the first and second anchor members 152, 154 may be interwoven with the tubular body 110. For example, a plurality of interwoven wires 115 forming the tubular body 110 may extend radially outward to form the inner walls 159 of each of the first and second anchor members 152, 154, thereby allowing the entire tubular body 110 and the inner walls 159 of the first and second anchor members 152, 154 to be formed continuously from the same plurality of wires 115. In some examples, the inner walls 159 define a second internal space 155 within each of the first and second anchor members 152, 154 that communicates with the lumen 116 of the tubular body.

[0050] In another example, the tubular body 210 of the stent 200 may include first and second anchor members 252, 254 formed as separate elements attached to the tubular body 210. See Figure 5. The first and second anchor members 252, 254 may be formed from one or more wires in a similar manner to the tubular body 210 and may be attached by any suitable method, including welding or adhesive. Each of the first and second anchor members 252, 254 includes an outer wall 258 and an inner wall 259, which are separately attached to the tubular body 210 at intervals from each other, and may define a first internal space 253 between the outer wall 258 and the inner wall 259. The tubular body 210 is formed by a single wall 217, which extends over the respective bases 251 of the first and second anchor members 252, 254, thereby allowing the inner walls 259 of the first and second anchor members 252, 254 to define a second internal space 255 separated from the lumen 216 of the tubular body 210 by a plurality of interwoven wires forming the single wall 217 of the tubular body 210.

[0051] The double-wall structure allows the stent to move and bend while maintaining its position during anastomosis. The inner wall 159 provides an additional layer or wall of wire within the outer wall 158, enhancing longitudinal strength and pull-out resistance to prevent movement of the stent 100. The additional wall of wire defined by the inner wall 159 can enable the formation of the anastomosis by applying radial force and can also maintain the lumen 116 in an open configuration to allow the passage of fluids and / or food. The outer wall 158 and the inner wall 159 can move independently of each other because they are connected only at the bases 151 of the first anchor member 152 and the second anchor member 154, or separately to only the walls 217 of the tubular body 210. This independent movement allows the outer wall 158 of the second anchor member 154 to grip the stomach wall and the outer wall 158 of the first anchor member 152 to grip the jejunal wall, and in the event of potential movement, the inner walls 159 of each flange provide additional strength to resist such movement.

[0052] The stent 100 can be sized to achieve a desired fluid velocity through the stent 100. Figures 4A and 4B show the locations of the following measurements. In some examples, the stent may have a diameter (LD) of lumens 116 of 15 mm to 30 mm. The longitudinal length (L) of the saddle region 118 may be 5 mm to 15 mm. The outer diameter (ODI) of the inner wall 159 of the first and second anchor members 152, 154 may be 20 mm to 35 mm, and the outer diameter (ODO) of the outer wall 158 of the first and second anchor members 152, 154 may be 25 mm to 40 mm. In some examples, the distance (S1) between the inner wall 159 and the outer wall 158 measured longitudinally may be 0.5 mm to 1.5 mm. In some examples, the distance (S2) between opposing ends of the inner wall 159 measured longitudinally at the base 151 may be 1.5 mm to 2.5 mm. For example, LD may be approximately 20 mm, L may be approximately 10 mm, ODI may be approximately 25 mm, ODO may be approximately 30 mm, S1 may be approximately 1 mm, and S2 may be approximately 2 mm.

[0053] A method for forming an anastomosis between spaced-apart first and second biological organs includes implanting a stent 100 by penetrating the first tissue wall 12 of the first biological organ 10 and the second tissue wall 18 of the second biological organ 17, such that the first open end 112 of the stent 100 is positioned within the first biological organ 10 and the second open end 114 of the stent 100 is positioned within the second biological organ 17. The stent 100 may be delivered in a longitudinally expanded and radially compressed form, such that the first and second anchor members 152, 154 are compressed to substantially the same outer diameter as the first and second end regions 111, 113 and saddle region 118. The stent 100 may be delivered through a catheter or endoscope. Once removed from the catheter or endoscope, the stent 100 may self-expand into the form shown in Figure 3. In other examples, the stent 100 may be expanded using a balloon or other mechanical device. The first and second anchor members 152, 154 may be self-expanding. The stent 100, including the tubular body 110, may be formed from one or more woven wires 115, and the tubular body 220 defines a lumen 116 extending between the first and second open ends of the stent 100. The one or more woven wires 115 forming the tubular body 110 may also extend to the first and / or second anchor members 152, 154, which are spaced longitudinally and extend radially outward from the tubular body 110, thereby forming the first and / or second anchor members 152, 154. Each of the first anchor member 152 and the second anchor member 154 has an outer diameter larger than the outer diameter of the saddle region 118 extending between the first anchor member 152 and the second anchor member 154, and each of the first anchor member 152 and the second anchor member 154 includes an outer wall 158 and an inner wall 159 spaced apart from the outer wall 158. The tubular body 110 can be defined by only a single wall 117 formed from one or more interwoven wires.The stent 100 can be implanted with the first tissue wall 12 of the first biological organ and the second tissue wall 18 of the second biological organ positioned in the saddle region 118, the first anchor member 152 positioned within the first biological organ 10, and the second anchor member 154 positioned within the second biological organ 17. This method further includes discharging fluids and particles from the first biological organ 10 into the second biological organ 17 through the lumen of the stent 100.

[0054] Figure 6 is a side cross-sectional view of another exemplary stent 300, which includes a tubular body 310 and a single anchor member 352 positioned adjacent to the first open end 312. The anchor member 351 has a double-wall structure including an inner wall 359 and an outer wall 358, as described above with respect to the first and second anchor members 152, 154 of stent 100. However, stent 300 differs from stent 100 in that it has only a single anchor member 352, and there is no anchor member adjacent to the second open end 314. The anchor member 352 may be formed in the same manner as described above. For example, the first group of wires forming the tubular body 310 may extend continuously to form the outer wall 358, while the second group of wires forming the tubular body 310 may extend continuously to form the inner wall 359. In other cases, the multiple wires forming the tubular body 310 may extend continuously to form the inner wall 359, while the outer wall 358 may be formed separately from separate woven wires and then attached to the tubular body 310. Other configurations are also possible. The stent 300 can be implanted across two organs, with the anchor member 352 positioned in the first organ and the remainder of the tubular body 310 and the second open end 314 positioned in the second organ. The length of the tubular body 310 may be set so that the second open end 314 remains in the second organ.

[0055] Stent 100, 200, and 300 can be of various types and stent structures. For example, stent 100, 200, and 300 can be self-expanding or balloon-expanding stents. Stent 100, 200, and 300 may be radially contracted into a folded or deflated form for delivery and then expandable into an expanded form while being placed in the body lumen. Thus, stent 100, 200, and 300 can be described as radially expandable or deformable. Self-expanding stents include those that have a spring-like action that causes the stent to expand radially, or stents that expand by the memory properties of the stent material to a specific form at a specific temperature. The stent's form can also be selected from many shapes. For example, a wire stent can be fixed in a continuous helical pattern, with or without wavy or zigzag patterns in the wire, to form a radially deformable stent. Individual ring-shaped or circular members can be connected by struts, sutures, welding, weaving, or locking the rings to form a tubular stent. In another embodiment, stents 100, 200, and 300 can be formed as monolithic tubular members by etching or cutting a pattern of interconnected struts from a tube.

[0056] It should be understood that this disclosure is illustrative in many respects. Modifications can be made in detail, particularly with respect to shape, size, and process configuration, without exceeding the scope of this disclosure. This may include, to a suitable extent, using any feature of one exemplary embodiment in other embodiments. Naturally, the scope of the invention is defined by the language expressed in the appended claims.

Claims

1. It is a stent, A tubular body formed from one or more woven wires, the tubular body having opposing first open end and second open end, and a lumen extending between the first and second open end, the tubular body defining a longitudinal axis and a length extending between the first and second open end, The first anchor member and the second anchor member are positioned adjacent to the first open end and adjacent to the second open end, wherein the first and second anchor members are spaced apart from each other by the saddle region of the tubular body, each of the first and second anchor members extends radially outward from the saddle region, and each of the first and second anchor members has an outer diameter larger than the outer diameter of the saddle region positioned between the first and second anchor members. A stent in which each of the first and second anchor members includes an outer wall and an inner wall spaced apart from the outer wall, and the tubular body is defined by a single wall.

2. The stent according to claim 1, wherein the outer walls of each of the first and second anchor members are interwoven with the tubular body.

3. The stent according to claim 2, wherein the inner wall defines an internal space within each of the first and second anchor members that communicates with the lumen of the tubular body.

4. The stent according to any one of claims 1 to 3, wherein the outer wall is attached to the inner wall only at the bases of the first and second anchor members, and the bases are adjacent to the tubular body.

5. The stent according to claim 1, wherein the tubular body extends over the bases of the first and second anchor members, and the first and second anchor members are formed as separate elements attached to the tubular body such that the inner walls define an internal space separated from the lumen by the one or more interwoven wires forming the tubular body.

6. The stent according to any one of claims 1 to 5, wherein the tubular body includes a first end region extending between the first open end and the first anchor member, and a second end region extending between the second open end and the second anchor member, and the outer diameters of the first and second anchor members are greater than the outer diameters of the first and second end regions.

7. The stent according to claim 6, wherein the outer diameters of the saddle region, the first end region, and the second end region are all substantially the same.

8. The stent according to any one of claims 1 to 7, wherein the first and second anchor members have lower flexibility than the tubular body.

9. The stent according to any one of claims 1 to 8, further comprising a cover that covers and extends over the tubular body, wherein the cover is not provided on the entirety of each of the first and second anchor members.

10. The stent according to any one of claims 1 to 8, further comprising a cover extending over the entire tubular body and over the inner walls of each of the first and second anchor members.

11. The stent according to claim 10, wherein the outer wall of each of the first anchor member and the second anchor member is not provided with the cover.

12. It is a stent, A tubular body formed from one or more woven wires, the tubular body having opposing first open ends and second open ends, and a lumen extending between the first and second open ends, the tubular body having a longitudinal axis defined by the tubular body, A stent comprising: a first anchor member and a second anchor member, spaced apart in the longitudinal direction, each of the first and second anchor members having a base adjacent to the tubular body and extending radially outward to a free end, each of the first and second anchor members having an outer diameter larger than the outer diameter of the tubular body positioned between the first and second anchor members, each of the first and second anchor members defining a double-wall flange structure including a substantially U-shaped outer wall and a substantially U-shaped inner wall spaced apart from the outer wall, the inner wall being fixed to the outer wall only at its base such that the outermost free end of the inner wall in the radial direction can move freely within the outer wall.

13. The stent according to claim 12, wherein at least one of the outer wall and the inner wall of each of the first and second anchor members is interwoven with the tubular body, and the inner wall defines an internal space within each of the first and second anchor members that communicates with the lumen of the tubular body.

14. The stent according to claim 12, wherein the tubular body extends across the bases of each of the first and second anchor members, and the first and second anchor members are formed as separate elements attached to the tubular body such that their inner walls define an internal space separated from the lumen by the one or more interwoven wires forming the tubular body.

15. A method for forming an anastomosis between a first biological organ and a second biological organ that are spaced apart from each other, The procedure involves implanting a stent by penetrating the first tissue wall of the first biological organ and the second tissue wall of the second biological organ. The first open end of the stent is positioned within the first biological organ, and the second open end of the stent is positioned within the second biological organ. The aforementioned stent is It includes a tubular body formed from one or more woven wires, The tubular body defines a lumen extending between the first and second open ends, and the stent includes a first anchor member and a second anchor member arranged at longitudinal intervals extending radially outward from the tubular body. Each of the first and second anchor members has an outer diameter larger than the outer diameter of the saddle region extending between the first and second anchor members, and each of the first and second anchor members includes an outer wall and an inner wall spaced apart from the outer wall, and the tubular body is defined by only a single wall. The stent is embedded such that the first tissue wall of the first biological organ and the second tissue wall of the second biological organ are positioned in the saddle region, the first anchor member is positioned within the first biological organ, and the second anchor member is positioned within the second biological organ. A method comprising discharging fluids and particles from the first biological organ through the lumen of the stent into the second biological organ.

Images