occlusion device

Abstract

The present application relates to a kind of occlusion devices comprising a wire mesh and a retraction member, the wire mesh comprising a connected inner recess segment and support segment, one end of the inner recess segment is connected with the retraction member, the other end of the inner recess segment is connected with the support segment, the inner recess segment is at least partially located inside the support segment, the proximal end of the retraction member is spaced apart from the proximal end face of the occlusion device, and the proximal end of the retraction member is closer to the distal end of the occlusion device than the proximal end face of the occlusion device. Thus, by spacing the proximal end of the retraction member from the proximal end face of the occlusion device, the wire mesh still has a certain blood flow space on the proximal end side of the retraction member to form a guide surface, so that before the blood flow contacts the retraction member, the blood flow needs to flow through the guide surface first to enter the inner recess segment, the flow rate of the blood flow slows down, reducing the generation of white thrombus, and at the center of the recess, the blood flow forms a vortex and has a slow flow rate, so the blood flow is easy to form a red thrombus at this position to make the thrombus can accumulate in a shorter time to cover the retraction member.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to a sealing device. Background Technology

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] Abnormal vascular pathways are non-physiological vascular connections within the body caused by congenital developmental abnormalities, acquired compensation, or trauma. Many common clinical diseases are accompanied by the presence of abnormal vascular pathways. Examples include: complex cyanotic congenital heart disease often accompanied by large collateral branches from the aorta to the pulmonary artery; complex arteriovenous aneurysms and arteriovenous fistulas in different locations; coronary artery-ventricular fistulas; abnormal intracardiac defects in congenital heart disease; abnormal blood vessels present within the body; and blood vessels that need to be closed due to surgical procedures.

[0004] In existing technologies, such as Figure 1 As shown, a vascular occlusion device is usually implanted into a blood vessel to block abnormal vascular channels. The vascular occlusion device is usually fixed at both ends with metal emboli 110. The emboli 110 protruding outward from both ends of the occlusion device has a large mass and high rigidity. When the emboli 110 is subjected to the scouring of blood flow, the shear stress of the blood flow is large, which can easily stimulate clotting factors (e.g., platelets or fibrin) to form white thrombi. White thrombi are easy to carry away with the blood flow and form blockages in areas with small blood vessel diameters. Summary of the Invention

[0005] Therefore, it is necessary to provide a sealing device, including a wire mesh and a gathering member. The wire mesh includes a concave section and a support section connected to each other. One end of the concave section is connected to the gathering member, and the other end of the concave section is connected to the support section. The concave section is at least partially located inside the support section. The proximal end of the gathering member is spaced apart from the proximal end face of the sealing device, and the proximal end of the gathering member is closer to the distal end of the sealing device than the proximal end face of the sealing device.

[0006] Optionally, the ratio of the distance between the proximal end of the condenser and the proximal end face of the sealing device to the axial length of the sealing device is between 1 / 3 and 1 / 2.

[0007] Optionally, it also includes a covering film. The concave section includes a first region and a second region connected axially. The first region is closer to the proximal end of the sealing device than the second region. The gathering member gathers the free end of the mesh wire in the second region. The covering film is located inside the mesh and sewn onto the first region. The covering film forms a free area at the location of the second region.

[0008] Alternatively, the metal coverage of the wire mesh in the concave section is less than that in the support section.

[0009] Optionally, the wire density of the mesh in the concave section is less than the mesh density in the support section, or the wire diameter of the mesh in the concave section is less than the wire diameter in the support section.

[0010] Optionally, the wire mesh includes support rods and a mesh structure, the mesh structure being connected to the support rods, one end of all support rods being connected to the wire mesh and arranged along the circumference of the wire mesh, and the other end of all support rods being connected to a gathering member, so that the concave section presents a bare support rod structure.

[0011] Optionally, the sealing device also includes a membrane, with an opening at or near the distal end of the wire mesh, the membrane extending from the concave section to the support section.

[0012] Optionally, the distal end of the wire mesh is bent radially inward to form a frustum structure, with the opening located at the center of the proximal end of the frustum structure.

[0013] Optionally, the coating is applied to the sidewall of the frustum structure.

[0014] Optionally, it may also include a coagulation-promoting layer disposed on the gathering member.

[0015] Optionally, the coagulant layer may include any one of a fiber woven mesh, a coagulant sponge, or a coagulant gelatin.

[0016] Optionally, the coagulation layer includes loose fiber threads wound around the circumferential sidewalls of the gathering member.

[0017] Compared with the prior art, the sealing device of the present invention has the following advantages:

[0018] The mesh includes a concave section and a support section connected together. One end of the concave section is connected to a gathering member, allowing the gathering member to be located within the recess of the mesh formed by the concave section. The proximal end of the gathering member is spaced apart from the proximal end face of the sealing device, so that the mesh still has a certain blood flow space on the proximal side of the gathering member to form a guide surface. Before the blood flow comes into contact with the gathering member, it needs to flow through the guide surface to enter the concave section. Thus, when the blood flow enters the concave section, the blood flow velocity slows down, reducing the formation of white thrombi. At the center of the recess, the blood flow forms a vortex and the flow velocity is slower. The blood flow is more likely to form red thrombi at this location, so that the thrombus can accumulate in a short time to cover the gathering member and promote endothelialization of the end face. Attached Figure Description

[0019] Figure 1 A schematic diagram of the structure of a occlusion device after it has been implanted in the human body in the prior art;

[0020] Figure 2 This is a schematic diagram of the sealing device in Embodiment 1 of the present invention;

[0021] Figure 3 This is a schematic diagram of the wire mesh structure in Embodiment 1 of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the gathering component in Embodiment 1 of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of the occlusion device after it is implanted into the human body according to Embodiment 1 of the present invention;

[0024] Figure 6 For the present invention Figure 2 Enlarged schematic diagram of the structure at point A in the diagram;

[0025] Figure 7 This is a schematic diagram showing the cooperation between the sealing device and the conveyor in Embodiment 1 of the present invention;

[0026] Figure 8 This is a schematic diagram of the unfolded structure of the wire mesh in Embodiment 1 of the present invention;

[0027] Figure 9 This is a schematic diagram of another embodiment of the wire mesh in Embodiment 1 of the present invention;

[0028] Figure 10 This is a schematic diagram of another embodiment of the wire mesh in Embodiment 1 of the present invention;

[0029] Figure 11 This is a schematic diagram of the sealing device in Embodiment 2 of the present invention. Detailed Implementation

[0030] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] In the field of interventional medical devices, "distal" is defined as the end furthest from the operator during surgery, and "proximal" is defined as the end closest to the operator during surgery. "Axial" refers to the direction parallel to the line connecting the center of the distal and proximal ends of the medical device, and "radial" refers to the direction perpendicular to the aforementioned axial direction. In this invention, the end of the occlusion device connected to the delivery system is defined as the proximal end, and the end of the occlusion device furthest from the delivery system is defined as the distal end.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0033] Example 1

[0034] This embodiment provides a sealing device 100, which can be used to intervene in blood vessels to seal abnormal vascular channels, arteriovenous aneurysms, arteriovenous fistulas, coronary artery ventricular fistulas, abnormal intracardiac defects of congenital heart disease, and other lesions.

[0035] like Figure 2 , Figure 3 As shown, the sealing device 100 includes a wire mesh 210 and a gathering member 220. The wire mesh 210 includes a concave section 211 and a support section 212 connected to each other. One end of the concave section 211 is connected to the gathering member 220, and the other end of the concave section 211 is connected to the support section 212. The concave section 211 is at least partially located inside the support section 212. The proximal end of the gathering member 220 is spaced apart from the proximal end face of the sealing device 100, and the proximal end of the gathering member 220 is closer to the distal end of the sealing device 100 than the proximal end face of the sealing device 100.

[0036] The wire mesh 210 has a certain degree of elasticity and can be made of nickel-titanium based shape memory alloy, iron-based shape memory alloy, copper-based shape memory alloy, or medical-grade stainless steel. In one embodiment, the wire mesh 210 is formed from a nickel-titanium alloy tube through laser cutting and heat setting. For example, the nickel-titanium alloy tube is laser-cut to form a tubular wire mesh 210. One end of the wire mesh 210 is connected to the gathering member 220, and then the wire mesh 210 is installed on a mold and subjected to heat setting, forming a concave section 211 at one end of the wire mesh 210, with the remaining portion forming a support section 212.

[0037] It should be noted that, as Figure 3 As shown in the axial cross-sectional view of the wire mesh 210, the wire mesh 210 bends radially inward to form a concave section 211. The inflection point at the bend forms the boundary between the concave section 211 and the support section 212. All inflection points are located on the same plane, which forms the proximal end face of the wire mesh 210 (i.e., the proximal end face of the sealing device 100). The wire mesh 210 radially outside the line l1 connecting the inflection point and the distal end is the support section 212, and the wire mesh 210 between the two radially opposite sides of l1 is the concave section 211. The upper contour line of the concave section 211 connects with the upper contour line of the support section 212.

[0038] The concave section 211 may be partially or completely located inside the support section 212. One end of the concave section 211 is connected to the gathering member 220, such that the gathering member 220 is located inside the concave section 211, or that the gathering member 220 is wrapped by the concave section 211. The other end of the concave section 211 is connected to the support section 212, such that the concave section 211 and the support section 212 together form a mesh 210. A recess is formed on the proximal side of the concave section 211. The support section 212 extends distally from the position where it is connected to the concave section 211.

[0039] like Figure 2 As shown, the proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200 are spaced apart. The proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200 have a certain distance between them. The proximal end face 221 of the sealing device 200 refers to the end face m closest to the proximal end in the axial direction of the wire mesh 210. The distance x1 between the proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200 is between 4-10 mm. Specifically, the distance x1 between the proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200 can be 4 mm, 5 mm, 5.3 mm, 6 mm, 7 mm, 8 mm or 9 mm. The proximal end 221 of the retractor 220 is closer to the distal end of the blocking device 100 than the proximal end face 230 of the blocking device 100, that is, the proximal end 221 of the retractor 220 is located on the distal side of the proximal end face 230 of the blocking device 100.

[0040] like Figure 4 As shown, the gathering member 220 has a threaded hole 222 at one end and a receiving hole 223 at the other end. The threaded hole 222 is located at the proximal end of the gathering member 220 and is used to cooperate with the conveyor to connect or disconnect the sealing device 200 from the conveyor. The receiving hole 223 is located at the distal end of the gathering member 220, and the distal end of the concave section 211 is gathered into the receiving hole 223 and then fixedly connected to the gathering member 220. The proximal end of the wire mesh 210 can be directly welded or bonded to the gathering member 220.

[0041] like Figure 5 As shown, when the occlusion device 200 is implanted at the bifurcation of the blood vessel, when the blood flow f1 passes through the proximal side of the occlusion device 200, some of the blood f2 enters the center of the concave segment 211 under the guidance of the side wall of the concave segment 211. The blood flow in this area can form a vortex, the flow velocity slows down, and thus a thrombus is formed.

[0042] The advantage of this design is that the mesh 210 includes a connected concave section 211 and a support section 212. One end of the concave section 211 is connected to the gathering member 220, allowing the gathering member 220 to be located within the recess of the mesh 210 formed by the concave section 211. The proximal end 221 of the gathering member 220 is spaced apart from the proximal end face of the sealing device 200, ensuring that the mesh 210 still has a certain space for blood flow on the proximal side of the gathering member 220 to form a guide surface. Before the blood flow comes into contact with the gathering member 220, it needs to flow through the guide surface to enter the concave section 211. As a result, when the blood flow enters the concave section 211, the blood flow velocity slows down, reducing the formation of white thrombi. At the center of the recess, the blood flow forms a vortex and the flow velocity is slower, making it easier for red thrombi to form at this location. This allows the thrombi to accumulate in a short time to cover the gathering member 220 and promote endothelialization of the end face.

[0043] like Figure 2 As shown, the ratio of the distance x1 between the proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200 and the axial length x2 of the sealing device 200 is between 1 / 3 and 1 / 2.

[0044] The proximal end 221 of the gathering member 220 is connected to the concave section 211. The proximal end face 230 of the sealing device 200 refers to the end face m closest to the proximal end in the axial direction of the wire mesh 210. The distance between the gathering member 220 and the proximal end face 230 of the sealing device 200 refers to the interval distance x1 between the proximal end 221 of the gathering member 220 and the proximal end face 230 of the sealing device 200. The axial length of the sealing device 200 refers to the interval distance x2 between the closest ends of the sealing device 200. The ratio of the distance x1 between the proximal end of the gathering member 220 and the proximal end face m of the sealing device 200 to the axial length x2 of the sealing device 200 is between 1 / 3 and 1 / 2. For example, the ratio can be 1 / 3, 1.2 / 3, 1.3 / 3 or 1 / 2.

[0045] It should be noted that when the ratio of the distance between the proximal end 221 of the condenser 220 and the proximal face 230 of the occlusion device 200 to the axial length of the occlusion device 200 is less than 1 / 3, the depression formed by the concave segment 211 is shallower, making it easier for blood flow to follow the blood flow at the concave segment 211, thus reducing the rate of red blood clot formation. When the ratio of the distance between the proximal end 221 of the condenser 220 and the proximal face 230 of the occlusion device 200 to the axial length of the occlusion device 200 is greater than 1 / 2, the condenser 220 is too close to the proximal end, resulting in a large deformation stroke when the condenser 220 is released, which in turn leads to low release stability.

[0046] The advantage of this arrangement is that by positioning the condenser 220 at a point where the ratio of the distance between the proximal end 221 of the condenser 220 and the proximal end face 230 of the occlusion device 200 and the axial length of the occlusion device 200 is between 1 / 3 and 1 / 2, the condenser 220 can be located close to the center of gravity of the occlusion device 200. On the one hand, this reduces the mass of the proximal end of the occlusion device 200, thereby reducing the shear stress generated by blood flow scouring at the proximal end. On the other hand, it creates a sufficiently deep concave region between the proximal end of the condenser 220 and the proximal end face of the occlusion device 200, allowing the blood flow to form a bottom vortex and a surface vortex within the concave section 211. The bottom vortex covers the condenser 220 and has a slower flow velocity, thus promoting the thrombus formation rate in the region near the condenser 220.

[0047] It is understood that in some embodiments, the gathering member 220 may also be disposed at the center of mass of the sealing device 200, where the center of mass refers to the location of the center of mass of the sealing device 200.

[0048] like Figure 2 As shown, the sealing device 200 also includes a covering membrane 240, which is circumferentially sewn to the largest diameter of the support section 212, and the covering membrane 240 is at least partially connected to the wire mesh 210 on the concave section 211.

[0049] The membrane 240 includes any one of PTFE, PE, and PU membranes. The circumferential contour of the membrane 240 corresponds to the circumferential contour of the support section 212. The maximum diameter of the support section 212 refers to the radial section with the largest diameter of the support section 212. The circumferential edge of the membrane 240 is attached to the inner wall of the support section 212 with the largest diameter. The membrane 240 can be sewn, bonded, or hot-pressed to the inner wall of the support section 212 with the largest diameter. The membrane 240 can also be attached to the inner wall of the concave section 211 and is at least connected to the mesh of the upper part of the concave section 211.

[0050] Thus, by placing the membrane 240 at the largest diameter point on the support section 212, the membrane 240 is connected to at least a portion of the wire mesh 210 on the concave section 211, allowing the membrane 240 to form a flow barrier on the inner side of the concave section 211, thereby promoting the accumulation of blood flow on the concave section 211.

[0051] like Figure 6 As shown, the concave section 211 includes a first region 2111 and a second region 2112 connected axially. The first region 2111 is closer to the proximal end of the sealing device 100 than the second region 2112. The gathering member 220 gathers the free end of the mesh wire in the second region. The covering film 240 is located inside the mesh 210 and sewn onto the first region 2111. The covering film 240 forms a free area at the location of the second region 2112.

[0052] In this embodiment, with the proximal end face of the gathering member 220 as the boundary l3, the region of the concave segment 211 approaching l3 from the proximal end is designated as the first region 2111, and the region of the concave segment 211 approaching l3 from the distal end is designated as the second region 2112. The first region 2111 and the second region 2112 are axially connected, with the first region 2111 located on the proximal side of the second region 2112. In the first region 2111, the intersection of the covering film 240 and the mesh 210 is connected, and the covering film 240 adheres to the sidewall of the mesh 210. In the second region 2112, there is no connection point between the covering film 240 and the mesh 210. For example, refer to... Figure 6 In the first region 2111, the film 240 and the screen 210 have multiple stitching points 241, which fix the film 240 to the first region 2111. In the second region 2112, the film 240 and the screen 210 do not have stitching points 241.

[0053] The membrane 240 is not constrained by the wire mesh 210 in the first region 2111. When the membrane 240 is subjected to the flushing action of blood flow, compared with the first region 2111 where the membrane 240 is connected to the wire mesh 210, the membrane 240 can generate greater displacement relative to the wire mesh 210 in the second region 2112, thereby forming a free zone. That is to say, in this embodiment, the free zone refers to the region where the membrane 240 is not constrained by the wire mesh 210 in the second region 2112. In the location of the free zone, the membrane 240 has a greater space for free movement.

[0054] Thus, after the occlusion device 200 is implanted into the human body, the membrane 240 on the first region 2111 guides the blood flow, directing the blood flow into the second region 2112. When the blood flow enters the second region 2112, the membrane 240 is no longer constrained by the wire mesh 210, and can thus deform toward the distal end to provide a certain buffer space for the blood flow, reduce the flow velocity of the blood flow in the second region 2112, and promote the deposition of blood in the second region 2112.

[0055] like Figure 2 As shown, the stiffness of the wire mesh 210 at the concave section 211 is less than that at the support section 212.

[0056] Stiffness refers to the ability of the wire mesh 210 to resist elastic deformation when subjected to force. The greater the stiffness, the stronger the resistance to deformation of the wire mesh 210; conversely, the smaller the stiffness, the weaker the resistance to deformation. Stiffness can be measured using a force gauge. For example, in one embodiment, the stiffness of the support section 212 is tested as follows: the pressure head of the force gauge is placed against the outer wall of the support section 212. The reading of the force gauge is then adjusted to zero. The measuring scale is adjusted until the pointer points to zero, and pressure is applied. When the displacement scale moves to 30% of the diameter of the support section 212, the force value displayed on the force gauge is recorded. The deformation resistance of the concave section 211 is as follows: the pressure head of the force gauge is placed against the outer wall of the concave section 211. The reading of the force gauge is then adjusted to zero. The measuring scale is adjusted until the pointer points to zero, and pressure is applied. When the displacement scale moves to 30% of the diameter of the concave section 211, the force value displayed on the force gauge is recorded.

[0057] It should be noted that, as Figure 7 As shown, the conveyor 300 includes a sheath 310 and a steel cable 320. The steel cable 320 is inserted inside the sheath 310 and is detachably connected to the retractor 220. During the loading of the sealing device 200, the steel cable 320 is connected to the retractor 220, and then the concave section 211 is straightened through the steel cable 320 so that the concave section 211 first enters the sheath 310. Then, the support section 212 is pulled into the sheath 310 through the steel cable 320, thereby realizing the loading of the sealing device 200. During the release of the sealing device 200, the sheath 310 is retracted proximally while the position of the steel cable 320 remains unchanged. First, the support section 212 is released from the sheath 310. Then, the sheath 310 continues to retract, releasing the straightened concave section 211. Next, the steel cable 320 and the retracting member 220 are released. Under the influence of the tensile force and shape memory of the wire mesh 210, the retracting member 220 springs back to the inside of the support section 212, thus releasing the sealing device 200. It can be understood that during the loading and release of the sealing device 200, because the concave section 211 is relatively close to the center of the wire mesh 210, it experiences greater stress and a longer deformation stroke during loading and release.

[0058] Because the concave section 211 in this application has a large depth, the loading stress of the concave section 211 and the gathering member 220 is large after the wire mesh 210 is stretched and loaded. In addition, the deformation stroke of the gathering member 220 is large and the stress is also large during the release process, which leads to the unstable release of the sealing device 200. Therefore, by setting the stiffness of the wire mesh 210 at the concave section 211 to be less than that at the support section 212, the loading stress of the concave section 211 is reduced, and the stress of the gathering member 220 during the release process is also weakened, so that the release of the sealing device 200 is more stable.

[0059] like Figure 8 As shown in the unfolded schematic diagram of the wire mesh 210, the metal coverage of the wire mesh 210 at the concave section 211 is less than the metal coverage on the support section 212.

[0060] It should be noted that the metal coverage rate refers to the ratio of the area of ​​the metal part to the total planar area of ​​the wire mesh 210 after the support is unfolded, that is, the metal coverage rate per unit area. The smaller the metal coverage rate, the smaller the total area of ​​the support occupied by metal, which means that the hollow area of ​​the support is larger, resulting in lower stiffness in that area. Consequently, the stiffness of the wire at the concave section 211 is smaller, reducing the stress during loading and unloading of the gathering member 220.

[0061] The surface metal coverage rate per unit area of ​​the wire mesh in the concave section is between 5% and 20%, specifically, it can be 5%, 8%, 10%, 13%, 16%, or 20%. The surface metal coverage rate per unit area of ​​the support section in the concave section is between 10% and 40%, specifically, it can be 10%, 15%, 20%, 27%, 30%, 35%, or 40%. In this embodiment, the metal coverage rate can be calculated by modeling the sealing device using three-dimensional reverse scanning, calculating the surface area ratio of the entity (metal part). For example, in one embodiment, a developer is sprayed onto the outer surface of the sealing device product, and a three-dimensional scanner is used to perform a full-range scan of the sealing device product. The shape model data of the sealing device product is imported into three-dimensional software for testing and calculation. The measurement tools in the three-dimensional software are used to measure the surface area of ​​the metal rods in the concave section and the support section, and the surface metal coverage rate per unit area of ​​the concave section and the support section is calculated.

[0062] like Figure 8 As shown, the wire mesh 210 includes support rods 214 and a mesh structure 213, with the mesh structure 213 connected to the support rods 214. One end of each support rod 214 is connected to the wire mesh 210 and arranged circumferentially along the wire mesh 210. In this embodiment, the wire mesh 210 is formed by laser cutting a tubular metal part. In the partially unfolded configuration of the wire mesh 210, multiple support rods 214 are arranged in an equidistant array along the width direction. The diameter or width of the support rods 214 is between 0.15 and 0.4 mm; for example, the diameter or width of the support rods 214 can be 0.15, 0.18, 0.25, 0.3, or 0.4 mm. In the enclosed configuration of the wire mesh 210 (i.e., the three-dimensional configuration of the sealing device 200), the support rods 214 are arranged axially along the sealing device 200, and multiple support rods 214 are arranged in a circumferential array along the sealing device 200. The support rod 214 forms the main support frame of the sealing device 200, providing sufficient radial support force for the sealing device 200. The support rod 214 extends from the support section 212 to the concave section 211. The support rod 214 provides a certain degree of resistance to deformation for the support section 212.

[0063] The mesh structure 213 is located between two adjacent support rods 214 and is integrally connected to the two adjacent support rods 214. The diameter or rod width of the filaments in the mesh structure 213 is between 0.08 and 0.2 mm; specifically, the diameter or rod width can be 0.08, 0.1, 0.15, or 0.2 mm. The rod width or diameter of the filaments in the mesh structure 213 is smaller than the rod width or diameter of the support rods 214, and the mesh structure 213 has good deformability to better conform to the inner wall of the blood vessel.

[0064] In one embodiment, the mesh structure 213 has a lower wire density at the concave section 211 than at the support section 212.

[0065] It should be noted that wire density refers to the number of wires per unit area. A higher wire density means more wires per unit area, and a lower wire density means fewer wires per unit area. Wire density can be measured using a microscope. In one embodiment, a sealing device 200 is used, and a 5mm × 5mm area is marked on the concave section 211. This area is magnified using an electron microscope, and the number of wires in this area is counted to obtain the wire density on the concave section 211. Similarly, a 5mm × 5mm area is marked on the support section 212, and this area is magnified using an electron microscope, and the number of wires in this area is counted to obtain the wire density on the support section 212.

[0066] Therefore, the mesh density on the concave section 211 of the mesh structure 213 is less than that on the support section 212, resulting in a lower mesh density on the concave section 211 and thus a lower stiffness of the wires in the concave section 211, reducing the stress on the gathering member 220 during loading and unloading.

[0067] It is understood that, in one embodiment, the diameter of the mesh wires in the concave section 211 of the mesh structure 213 is smaller than the diameter of the mesh wires in the support section 212. The diameter of the mesh wire refers to the rod diameter or rod width of a single mesh wire. The larger the rod diameter or rod width, the greater the stiffness of the mesh wire, thereby making the stiffness of the mesh wires in the concave section 211 less than that in the support section 212, reducing the stress during loading and unloading of the gathering member 220.

[0068] In another embodiment, the diameter or width of the support rod 214 on the concave section 211 is smaller than the diameter or width on the support section 212. The diameter of the support rod 214 refers to the diameter or width of a single support rod 214. The larger the diameter or width, the greater the stiffness of the rod. This results in the stiffness of the support rod 214 on the concave section 211 being less than the stiffness of the support rod 214 on the support section 212, reducing the stress during loading and unloading of the retractable member 220.

[0069] In this embodiment, as Figure 8 As shown, the other end of all support rods 214 is connected to the retracting member 220 so that the concave section 211 presents a bare support rod structure. The mesh structure 213 extends from the distal end to the junction of the support section 212 and the concave section 211 so that the concave section 211 presents a bare support rod structure. In this embodiment, the bare support rod structure refers to the fact that only support rods 214 are provided at the concave section 211, while the mesh structure 213 is only provided at the support section 212. The junction of the support section 212 and the concave section 211 refers to the connection point between the support section 212 and the concave section 211. The support rod 214 includes a first section located at the support section 212 and a second section located at the concave section 211. The diameter of the first section is larger than that of the second section. The second section has better deformation performance than the first section, so that the concave section 211 has stress that can be adapted to the loading and releasing process of the retracting member 220.

[0070] In this way, the mesh structure 213 extends from the far end to the junction of the support section 212 and the concave section 211 through the other end of all the support rods 214 connected to the retractor 220. This makes the concave section 211 appear as a bare support rod 214 structure, avoiding the mesh structure 213 on the concave section 211 from constraining the deformation of the support rod 214. This makes it easier for the support rod 214 on the concave section 211 to deform to adapt to the stress generated by the loading and releasing of the retractor 220.

[0071] It is understood that in other embodiments, the support rod 214 extends from the distal end to the junction of the support section 212 and the concave section 211, and the mesh structure 213 extends from the distal end to the concave section 211.

[0072] In this way, only the mesh structure 213 is provided in the concave section 211, avoiding interference from the support rod 214 on the deformation of the mesh structure 213, thereby making the mesh structure 213 on the concave section 211 more easily deformable to adapt to the stress generated by the loading and releasing of the gathering member 220.

[0073] In another embodiment of this example, such as Figure 9 As shown, the wire mesh 210 has an opening 216 at its axial distal end, the film 240 extends from the concave section 211 to the support section 212, and the distal end of the wire mesh 210 is bent toward the radial inward to form a curved section 215.

[0074] The wire mesh 210 includes a distal end located at the axial distal end of the wire mesh 210. The distal end has an opening 216 formed by laser cutting one axial end of the wire mesh 210 structure. The other axial end of the wire mesh 210 is gathered by a gathering member 220, forming a pocket-shaped structure with a single-sided opening 216. In the concave section 211, a coating 240 corresponds to the contour of the wire mesh 210, extending along the inner wall of the wire mesh 210 from the concave section 211 to the support section 212. The distal end of the wire mesh 210 is bent radially inward to form a curved section 215, with one end of the curved section 215 facing proximally.

[0075] like Figure 9 As shown, the wire mesh 210 includes a concave section 211, a support section 212, and a curved section 215. In the axial section of the sealing device 200, the upper contour lines of the concave section 211, the support section 212, and the curved section 215 are connected sequentially. The wire mesh 210 includes a mesh structure 213 and a support rod 214. The mesh structure 213 can extend from the concave section 211 to the support section 212, or from the concave section 211 to the curved section 215, or it can be provided only on any section of the concave section 211, the support section 212, or the curved section 215. The support rod 214 can extend from the concave section 211 to the support section 212, or it can extend from the concave section 211 to the curved section 215, or it can be provided only on any section of the concave section 211, the support section 212, or the curved section 215.

[0076] The advantage of this design is that by opening 216 at the distal end of the wire mesh 210 and extending the membrane 240 from the concave section 211 to the support section 212, the occlusion device 200 forms a net-like structure with a single-sided opening 216. This slows down the blood flow velocity after the distal side enters the inner side of the wire mesh 210, making it easier for thrombi to accumulate, accelerating occlusion, and promoting endothelialization.

[0077] like Figure 10As shown, one end of the curved section 215 extends toward the radial center of the sealing device 200, and the opening 216 is located at the center of the curved section 215. The curved section 215 includes a first end connected to the support section 212 and a second end away from the support section 212. The second end extends toward the radial center. The curved section 215 is inclined relative to the axial direction of the sealing device 200. The curved section 215 forms a frustum structure at the distal end of the wire mesh 210. The width of the frustum structure gradually decreases from the distal end to the proximal end. The opening 216 is located at the center of the proximal end of the frustum structure, that is, the outline of the opening 216 is the outline of the second end. The ratio of the width of the opening 216 to the diameter of the sealing device 200 is between 0.2 and 0.7. Specifically, the ratio of the width d1 of the opening 216 to the diameter d2 of the sealing device 200 can be 0.2, 0.3, 0.6, or 0.7. A flow-blocking membrane 2153 is disposed on the outer wall of the curved section 215. The flow-blocking membrane 2153 includes any one of PTFE membrane, PE membrane, and PU membrane. The flow-blocking membrane 2153 is stitched, bonded, or heat-pressed to the sidewall of the curved section 215.

[0078] The advantage of this design is that by extending one end of the curved section 215 towards the radial center of the occlusion device 200, the curved section 215 can guide the blood flow. When the blood flow reaches the curved section 215, it flows towards the inside of the wire mesh 210 under the guidance of the curved section 215, promoting the aggregation and accumulation of blood flow on the inside of the wire mesh 210. By setting the flow-blocking membrane 2153 on the outer wall of the curved section 215, the distal end of the occlusion device 200 presents a frustum structure. The flow-blocking membrane 2153 can form a flow barrier on the outer wall of the curved section 215, increasing the difficulty of blood flow overflowing from the opening 216, further promoting the formation of red thrombus, accelerating occlusion, and promoting endothelialization.

[0079] Example 2

[0080] The difference between this embodiment and Embodiment 1 is that, as Figure 11 As shown, the sealing device 400 also includes a coagulation layer 450 disposed on the gathering member 420. The coagulation layer 450 is connected to the side wall of the gathering member 420 and is used to absorb blood to quickly form a thrombus.

[0081] The gathering member 420 has a threaded hole at its proximal end and a receiving hole at its distal end. The gathering member 420 is generally cylindrical in shape. The coagulation-promoting layer 450 is used to absorb blood to form a thrombus. The coagulation-promoting layer 450 includes at least one of the following: a fluffy fiber woven mesh, a coagulation-promoting sponge, a gel-promoting collagen sponge, an absorbable fluffy fiber woven mesh, polymer fiber strands, low-twist surgical sutures, or absorbable fiber sutures. In one embodiment, the coagulation-promoting layer 450 includes a fluffy fiber mesh made of fluffy fiber strands. The fluffy fiber mesh covers the circumferential sidewall of the gathering member 420 and can be bonded, sutured, or sleeved onto the gathering member 420. It is understood that in another embodiment, the gathering member 420 has a winding groove, and the coagulation-promoting layer 450 is formed by winding polymer fiber strands, low-twist surgical sutures, or biodegradable fiber sutures around the circumferential sidewall of the gathering member 420.

[0082] It should be noted that the fluffy fiber web in this embodiment is woven from fluffy fiber yarn or fiber strands. Fluffy fiber yarn or fiber strands include any one of the following: surgical suture thread, surgical suture strands, polylactic acid biodegradable fiber yarn, polylactic acid biodegradable fiber strands, chitin fiber strands, or chitin fiber yarn. It is understood that the twist of the yarn or strands used in this embodiment can be relatively low. Twist refers to the number of twists per unit length of fiber filament, yarn, or strand. Twisting refers to the process of twisting two or more filaments, fiber bundles, or strands axially to cohede them into yarn or strands. In this embodiment, the twist of the fiber yarn or fiber strand is between 1.3-6 Ttex; specifically, the twist of the fiber yarn or strand can be 1.3 Ttex, 1.8 Ttex, 2.3 Ttex, 3.5 Ttex, 5 Ttex, or 6 Ttex. It is understood that in this embodiment, the specification range of the fiber strand is 50D / 72F-80D / 72F. Specifically, the specifications of the fiber strands can be: 50D / 72F, 55D / 72F, 60D / 72F, 63D / 72F, 70D / 72F or 80D / 72F.

[0083] It is understood that in some embodiments, the coagulation-promoting layer 450 may further include a gelling collagen sponge, which is attached to the sidewall of the gathering member 420. The gelling collagen sponge is bonded or sewn to the sidewall of the gathering member 420, and the gelling collagen sponge protrudes radially outward from the gathering member 420. The outer wall of the gelling collagen sponge is at least partially in contact with the outer wall of the concave section 411. It is understood that in one embodiment, a winding groove is formed on the sidewall of the gathering member 420, the gelling collagen sponge is encased in the winding groove, one end of the collagen sponge is sewn into the winding groove of the gathering member 420 using sutures, and the other end, where the collagen is still diffused, is fixed to the concave end using sutures.

[0084] The advantage of this design is that, by including the gathering member 420 and the coagulation-promoting layer 450, with the coagulation-promoting layer 450 covering the side wall of the gathering member 420, the coagulation-promoting layer 450 forms a blood adhesion layer on the side wall of the gathering member 420. After blood forms a thrombus, it is easy to adhere to the coagulation-promoting layer 450. Compared with the exposed metal end, this increases the difficulty for the thrombus to pass through the concave section 411, thereby increasing the rate of thrombus accumulation, improving the speed of occlusion, and reducing the probability of the thrombus flowing away with the blood and blocking the blood vessel.

[0085] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An occlusion device, comprising: The wire mesh includes a concave section and a support section connected to each other, one end of the concave section is connected to the folding member, the other end of the concave section is connected to the support section, the concave section is at least partially located inside the support section, the proximal end of the folding member is spaced apart from the proximal end surface of the occlusion device, and the proximal end of the folding member is closer to the distal end of the occlusion device than the proximal end surface of the occlusion device. The occlusion device further comprises a covering film, the concave section comprises a first region and a second region connected in an axial direction, the first region is closer to the proximal end of the occlusion device than the second region, the folding member corresponds to the free end of the wire mesh in the second region, the covering film is located inside the wire mesh and is sutured to the first region, and the covering film forms a free area at the position of the second region.

2. The occlusion device of claim 1, wherein, The ratio of the spacing distance between the proximal end of the folding member and the proximal end surface of the occlusion device to the axial length of the occlusion device is between 1 / 3 and 1 / 2.

3. The occlusion device of claim 1, wherein, The metal coverage of the wire mesh at the concave section is less than the metal coverage on the support section.

4. The sealing device according to claim 3, characterized in that, The wire mesh density at the concave section is less than the mesh density at the support section, or the wire diameter of the wire mesh at the concave section is less than the wire diameter on the support section.

5. The occlusion device of claim 3, wherein, The wire mesh comprises support rods and a mesh structure connected to the support rods, one end of all the support rods is connected to the wire mesh and is arranged along the circumferential direction of the wire mesh, and the other end of all the support rods is connected to the folding member, so that the concave section appears as a bare support rod structure.

6. The occlusive device of claim 1, wherein, The occlusion device further comprises a covering film, and an opening is provided at the axial distal end or a position close to the distal end of the wire mesh, and the covering film extends from the concave section to the support section.

7. The occlusion device of claim 6, wherein, The distal end of the wire mesh is curved towards the radial inside to form a circular truncated cone structure, and the opening is located at the center of the proximal end of the circular truncated cone structure.

8. The occlusion device of claim 7, wherein, The covering film is arranged on the side wall of the circular truncated cone structure.

9. The occlusive device of claim 1, wherein, A coagulation-promoting layer is further arranged on the folding member.

10. The occlusion device of claim 9, wherein, The coagulation-promoting layer comprises any one of a fiber woven mesh, a coagulation sponge, or a coagulation gel.

11. The occlusive device of claim 9, wherein, The coagulation-promoting layer comprises a fluffy fiber line, and the fluffy fiber line is wound on the circumferential side wall of the folding member.

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