KR20220020548A - Double structure stent and the manufacturing method thereof - Google Patents

Abstract

A stent of the present invention comprises: a first structure having a structure in which wires are bent in a zigzag shape and connected to each other by a bent portion 11; and a second structure in which wires extending parallel to each other in a first spiral direction and wires extending parallel to each other in a second spiral direction opposite to the first spiral direction are braided and connected to each other, in which each of the wire in the first spiral direction and the wire in the second spiral direction of the second structure cross over radially inward wire segments at the plurality of junctions or cross under the plurality of radially outward wire segments, and the wire of the first spiral direction and the wire of the second spiral direction of the second structure cross and pass the lozenge-shaped space formed by the four bent portions of the first structure.

Description

Double structure stent and the manufacturing method thereof

The present invention relates to a dual structure stent including a first structure and a second structure and a method for manufacturing the same, and the stent according to the present invention has excellent flexibility, and deformation in the longitudinal and radial directions is minimized.

Recently, various methods have been disclosed to conveniently treat a lesion site such as a stenosis of a body or an aneurysm of a blood vessel without performing a surgical operation, and one of them is a procedure using a stent.

A stent is usually composed of a hollow cylindrical body having a number of spaces and a constant length by weaving a shape memory alloy material.

Conventionally, as a structure of a stent, a structure in which a wire is hung on the upper V-shaped structure (hereinafter, V-structure), or a structure in which the upper and lower ends do not overlap at the intersection while forming a single line to both ends (hereinafter, Y-structure) has been used a lot, and in recent years, attempts have been made to improve the function of the stent by various structural modifications, not limited to the above-described single structure.

As an example, Patent Documents 1 and 2 discloses a dual structure stent including a first structure having a V-structure and a second structure having a V-structure. The first stent and the second stent are connected by crossing over or under each other.

The stents of Patent Documents 1 and 2 described above, as constituted by two V-structures, have improved flexibility and conformability, and have the advantage that they can be configured in a desired shape. However, when an external force is applied to the stent, in each V-structure itself and/or between two V-structures, the stent cells overlap each node to cause kink, so that even after the external force is removed, the original shape is restored. There is a problem that it does not come back as it is and it shortens in a straight line. Therefore, the stents of Patent Documents 1 and 2 have a limitation that deployment is not easy.

As another example, Patent Document 3 proposes a double-structured stent composed of at least two mesh segments, an inner segment and an outer segment. The inner segment and the outer segment are connected together in one continuous piece, and the outer segment is inverted and folded over the inner segment to form a stent having a dual structure of the outer segment and the inner segment.

The stent of Patent Document 3 may have a double structure in an easy manner, but since the inner segment and the outer segment are simply connected by a fold, there is a limitation in that the connection between the segments is unstable. In addition, when deformation is applied to the stent, there is a problem in that precise deformation is difficult because the inner segment and the outer segment are not integrally deformed.

As another example, Patent Document 4 proposes a single-structure stent in which a V-structured intersecting section and a Y-structured intersecting section are alternately arranged.

However, in the stent of Patent Document 4, there is still a limitation of a single structure stent, and upon deployment, kink due to deformation occurs in the weaving section, and in the cross section, the deformation is extended to the periphery of the cell to which the deformation is applied, There is a limit in that it is difficult to use precisely.

Patent Document 1: International Publication WO2017/039389 (published on March 9, 2017)

Patent Document 2: Korean Patent Registration No. 10-2055990 (published on December 18, 2017)

Patent Document 3: US Patent Publication No. US 8,663,314 B2 (published on June 14, 2012)

Patent Document 4: Korean Patent Registration No. 10-1735702 (published on October 10, 2016)

An object of the present invention is to provide a stent that has excellent flexibility and minimizes deformation during deployment. In addition, the present invention does not generate a kink when a compressive force in the longitudinal direction is applied, and as the deformation is gently extended when a compressive force in the radial direction is applied, a stent that can be deployed in a shape suitable for the diseased site It is a challenge to provide

In one embodiment of the stent according to the present invention for solving the above problems, the stent is a structure in which the wire is bent in a zigzag shape and connected to each other by the bent portion 11, the first structure (1), and the first spiral direction The wire 21 extending parallel to each other and the wire 22 extending parallel to each other in the second spiral direction opposite to the first spiral direction are braided and connected to each other. A wire segment comprising a second structure (2), wherein each of the wire (21) in the first helical direction and the wire (22) in the second helical direction of the second structure (2), at a plurality of intersection points, is a radially inward wire segment In the rhombus-shaped space 12 formed by the four bends 11 of the first structure 1 , which crosses over or crosses under a plurality of radially outward wire segments, the second The wire 21 in the first helical direction and the wire 22 in the second helical direction of the two structures 2 may cross each other.

In one embodiment, the first helical wire 21 and the second helical wire 22 of the second structure 2 each run above the radially inwardly directed wire segment and below the radially outwardly directed wire segment. You can cross over alternately.

In one embodiment, the wire 21 of the first helical direction of the second structure 2 is, at a plurality of intersections, the wire segment of the first structure 1 or the second of the second structure 2 It is possible to cross the segments of the wire 22 in the helical direction.

In one embodiment, the first helical wire 21 of the second structure 2 comprises a wire segment of the first structure 1 and the second helical wire 22 of the second structure 2 . may alternately intersect the segments of

In one embodiment, at the center of the space 12 , the wire 21 in the first spiral direction and the wire 22 in the second spiral direction of the second structure 2 may cross each other.

In one embodiment of the method for manufacturing a stent according to the present invention, the wire is bent in a zigzag shape to form a first structure 1, which is a structure connected to each other by a bent portion 11, and a first spiral A structure in which wires 21 extending parallel to each other in a direction and wires 22 extending parallel to each other in a second spiral direction opposite to the first spiral direction are braided and connected a second step of forming a second structure (2), wherein each of the wire (21) in the first spiral direction and the wire (22) in the second spiral direction of the second structure (2) is formed at a plurality of intersection points , formed to cross over a segment of a radially inward wire segment or to cross over a segment of a radially outward wire segment, and formed by the four bends 11 of the first structure 1 , a rhombus space In the portion 12 , the wire 21 in the first helical direction and the wire 22 in the second helical direction of the second structure 2 can cross and pass.

In one embodiment, after the first step of forming the first structure 1 , the second step of forming the second structure 2 may be performed.

The stent according to the present invention has a structure that is connected by crossing the first structure of the V-structure and the second structure of the Y-structure from above or below, so that it has excellent flexibility, and at the time of deployment, the node according to the stent cell structure It shows the effect that there is no star overlap. In addition, when deformation is applied to the stent, it has the effect of being able to easily deploy the stent to the affected area by gently deforming the shape as it has a slight effect on the surrounding cells while having the expansion force for each cell. see.

By the method for manufacturing a stent according to the present invention, it is possible to manufacture a stent having both the advantages of the independent cell expansion force of the V-structure and the inhibition of kink generation of the Y-structure, and the V-structure and Y- structure having different connection methods Structures can be connected simply and easily.

1 is a stent according to the present invention.
FIG. 2 is an enlarged view of A of FIG. 1 .
3 is an enlarged view of (a) the stent of Comparative Example 1 prepared only with the first structure, and (b) B.
4 is an enlarged view of (a) the stent of Comparative Example 2 prepared only with the second structure, and (b) C. FIG.
5 is a comparison of the flexibility and conformability of (a) the stent of Example 1 according to the present invention, (b) the stent of Comparative Example 1, and (c) the stent of Comparative Example 2;
Figure 6 compares the kink generation of (a) the stent of Example 1 according to the present invention, (b) the stent of Comparative Example 1, and (c) the stent of Comparative Example 2.
7 is a comparison of the deformation angles of (a) the stent of Example 1 according to the present invention, (b) the stent of Comparative Example 1, and (c) the stent of Comparative Example 2.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Further, the present invention is not limited to the following embodiments, and may be realized in any feasible combination as well as in isolated manners that a person skilled in the art will recognize. Furthermore, the scope of the present invention is not limited by the preferred embodiments. Furthermore, embodiments are schematically illustrated in the drawings. Herein, like reference numbers in these drawings indicate identical or functionally similar elements.

1 shows the overall structure of the stent of the present invention, in one embodiment according to the present invention, the stent may be a hollow cylindrical having a longitudinal axis (X).

FIG. 2 is an enlarged view of A, which is a part of the stent according to FIG. 1 , wherein the stent may comprise a first structure 1 in a V-configuration and a second structure 2 in a Y-configuration. The number of structures constituting the stent is not limited to two, and may be three or more. In addition, the structure to be added may be a V-structure, a Y-structure, or other structures.

FIG. 3 shows an embodiment of a first structure 1 of a V-structure, and FIG. 4 shows an embodiment of a second structure 2 of a Y-structure.

Referring to FIG. 3 , the first structure 1 may have a structure in which wires are bent in a zigzag shape and connected to each other by a bent portion 11 . The bent portions 11 may be arranged at unequal intervals.

Referring to FIG. 4 , the second structure 2 includes wires 21 extending parallel to each other in a first helical direction, and parallel to each other in a second helical direction opposite to the first helical direction. The extending wires 22 may be braided and connected to each other. The first helical wire 21 and the second helical wire 22 may be woven to extend in parallel with the same or different spacing, respectively.

The stent according to an embodiment of the present invention includes both a first structure 1 having a V-structure and a second structure 2 having a Y-structure as shown in FIG. 2 . That is, the first structure 1, in which the wire is bent in a zigzag shape and connected to each other by the bent portion 11, and the wire 21 extending parallel to each other in the first spiral direction, and the first The second structure 2 may include a structure in which wires 22 extending parallel to each other in a second spiral direction opposite to the spiral direction are braided and connected to each other.

In one embodiment, each of the first helical wire 21 and the second helical wire 22 of the second structure 2 intersects over the radially inward wire segments at a plurality of intersection points. It may pass or cross under a plurality of radially outward wire segments.

In the present invention, a 'wire segment' may mean a part of the entire wire. That is, it may mean a part of the wire of the first structure 1, the wire 21 of the first spiral direction of the second structure 2, or the wire 22 of the second spiral direction of the second structure 2 there is. If, in addition to the first structure (1) and the second structure (2), other structures are included, the wire of the added structure may also be included.

In addition, in the present invention, 'radially inward' may mean radially close to the longitudinal axis (X) of the stent, and 'radially outward' means radially with respect to the longitudinal axis (X) of the stent. It can mean distant.

That is, the wire 21 of the first helical direction of the second structure 2 has a wire 22 segment of the second helical direction of the second structure 2 and/or the wire segment of the first structure 1 . if disposed radially inward, cross over it; The wire 21 in the first helical direction of the second structure 2 has a second helical wire 22 segment of the second structure 2 and/or the wire segment of the first structure 1 radially outward. If placed as a , you can cross and pass under it.

In the same way, the second helical wire 22 of the second structure 2 is a segment of the first helical wire 21 of the second structure 2 and/or the wire of the first structure 1 . If the segment is disposed radially inward, it crosses over it; The wire 22 in the second helical direction of the second structure 2 has a segment of the wire 21 in the first helical direction of the second structure 2 and/or the wire segment of the first structure 1 radially outward. If placed as a , you can cross and pass under it.

In one embodiment, in the rhombic space 12 formed by the four bent portions 11 of the first structure 1, the wire 21 in the first spiral direction of the second structure 2 and The wires 22 in the second helical direction can cross and pass.

In one embodiment, the first helical wire 21 of the second structure 2 may alternately cross over the radially inwardly inward wire segment and under the radially outwardly outward wire segment. Separately or simultaneously, the wire 21 in the first helical direction of the second structure 2 is formed between the segment of the wire 22 in the second helical direction of the second structure 2 and the first structure 1 . It may cross the wire segments, preferably alternately.

In one embodiment, the second helical wire 22 of the second structure 2 may alternately cross over the radially inwardly inward wire segments and under the radially outwardly outward wire segments. Separately or simultaneously, the wire 22 in the second helical direction of the second structure 2 is formed between the segment of the wire 21 in the first helical direction of the second structure 2 and the first structure 1 . It may cross the wire segments, preferably alternately.

In an embodiment, the first helical wire 21 of the second structure 2 is a segment of the second helical wire 22 of the second structure 2 and/or of the first structure 1 . The wire segments alternately cross from above or below, and at the same time, the wire 22 of the second helical direction of the second structure 2 , the wire 21 of the first helical direction of the second structure 2 , ) segments and/or wire segments of the first structure 1 alternately intersect above or below.

In one embodiment, in the rhombic space 12 formed by the four bent portions 11 of the first structure 1, the wire 21 in the first spiral direction of the second structure 2 and The wires 22 in the second helical direction can cross and pass. The number of intersections of the wires in the space 12 may be one or more.

In one embodiment, at the center of the space 12 , the wire 21 in the first helical direction and the wire 22 in the second helical direction of the second structure 2 may cross and pass.

According to the stent according to the present invention, while the coupling of the first structure (1) and the second structure (2) is strong, the first structure (1) and the second structure (2) can be flexibly deformed, so that various It has the advantage that it can be easily deployed to a location. In addition, the stent according to the present invention has an independent cell expansion force, which is an advantage of the V-structure, and at the same time has a characteristic that kink generation, which is an advantage of the Y-structure, is suppressed. Moreover, the stent according to the present invention can return to its original state when the deformation is removed while accommodating the deformation when deformation in the longitudinal and diametric directions is applied.

Next, a method for manufacturing a stent according to the present invention will be described. In the method of manufacturing a stent according to an embodiment of the present invention, the wire is bent in a zigzag shape to form a first structure (1) that is a structure connected to each other by a bent portion (11), and a first spiral A structure in which wires 21 extending parallel to each other in the direction and wires 22 extending parallel to each other in a second spiral direction opposite to the first spiral direction are braided and connected a second step of forming a second structure (2), wherein each of the wire (21) in the first helical direction and the wire (22) in the second helical direction of the second structure (2) is formed at a plurality of intersection points , formed to cross over a segment of a radially inward wire segment or cross over a segment of a radially outward wire segment to cross over and a rhombus space formed by the four bends 11 of the first structure 1 . In the portion 12 , the wire 21 in the first helical direction and the wire 22 in the second helical direction of the second structure 2 may cross each other.

In one embodiment, after the first step of forming the first structure 1 , the second step of forming the second structure 2 may be performed.

In one embodiment, forming the first structure 1 , after which the wire 21 in the first helical direction of the second structure 2 is placed above or below the wire segment of the first structure 1 . connecting so as to cross over, and thereafter, the wire 22 in the second helical direction of the second structure 2 is connected to the wire segment of the first structure 1 and/or the It may include the step of connecting to cross over or below the wire 21 segment in the second spiral direction.

In one embodiment, the second helical wire 22 of the second structure 2 may comprise alternatingly passing over the radially inwardly inward wire segment and under the radially outwardly outward wire segment. . Separately or simultaneously, the wire 22 in the second helical direction of the second structure 2 is formed between the segment of the wire 21 in the first helical direction of the second structure 2 and the first structure 1 . It may cross the wire segments and may preferably include alternating crossings.

According to the method for manufacturing a stent according to the present invention, the combination of the first structure (1) and the second structure (2) is simple and easy, and the manufactured stent has excellent properties in flexibility, expansion force, elasticity, deformation resistance, etc. There are advantages.

Next, below, the stent according to an embodiment of the present invention shown in FIGS. 1 and 2 (hereinafter, 'Example 1'), a stent consisting only of the V-structure shown in FIG. 3 (hereinafter, 'Comparative Example 1') ), and the properties of the stent consisting only of the Y-structure shown in FIG. 4 (hereinafter, 'Comparative Example 2') are compared. 5 (a) to (c) show the characteristics of flexibility and adaptability according to the modifications of Example 1, Comparative Example 1, and Comparative Example 2, respectively, and FIGS. 6 (a) to (c) are each carried out Example 1, Comparative Example 1, and Comparative Example 2 shows whether kink occurs according to the longitudinal compression, (a) to (c) of Figure 7 are in the radial direction of Example 1, Comparative Example 1 and Comparative Example 2, respectively shows the deformation angle and shape according to the compression of

Figure 3 shows the deformation of the stent after applying the folding deformation so that the length of the stent is half.

Figure 3 (a) shows the example 1, which has excellent flexibility and returns to its original shape when temporarily applied external force is removed. Therefore, the stent of Example 1 has the advantage that it can be stably deployed to any lesion site.

On the other hand, FIG. 3(b) is Comparative Example 1, and the conformability is very high, and after deformation is applied to the stent of Comparative Example 1, it is hardly possible to return to the original shape.

Figure 3 (c) is a comparative example 2, excellent flexibility and almost no conformability, even after applying a bending deformation of the stent, it is stretched to its original shape.

That is, Example 1 has the advantages of flexibility and deformation resistance similar to those of Comparative Example 2.

Next, Figure 4 shows the deformation of the stent after applying a compressive force in the longitudinal direction to the stent.

Figure 4 (a) is Example 1, when a compressive force is applied to the stent, overlap occurs for each node depending on the cell structure. . Therefore, since the stent of Example 1 does not have a problem that the length of the stent is shortened during deployment, deployment is easy.

Figure 4 (b) is Comparative Example 1, when a compressive force is applied to the stent, overlap occurs for each node depending on the cell structure, showing the result that the length of the stent is shortened in a straight line even after the compressive force is removed. Therefore, the stent of Comparative Example 1 is highly likely to cause a problem of shortening the stent length during deployment.

Figure 4 (c) is Comparative Example 2, when a compressive force is applied to the stent, there is no overlap for each node depending on the cell structure.

That is, Example 1 has an advantage that, like Comparative Example 2, kink does not occur even after a compressive force in the longitudinal direction is applied.

Next, Figure 5 shows the deformation of the stent in a state in which a compressive force is applied in the radial direction of the stent.

The stent of Comparative Example 1 shown in Fig. 5 (b) has an expansive force for each cell. Accordingly, since the cells in the portion to which the compressive force is applied do not affect the surrounding cells, the deformation angle is steep and the length of the deformed region is the shortest.

In the stent of Comparative Example 2 shown in FIG. 5(c), each cell has an expansive force in association with the surrounding cells. Accordingly, the cells in the portion to which the compressive force is applied also affect the surrounding cells, and the length of the deformed region is excessively long.

The stent of Example 1 shown in Figure 5 (a), while having an expansive force for each cell, affects the surrounding cells to some extent.

Accordingly, the deformation angle and the length of the deformed region of Example 1 are most suitable as intermediate between those of Comparative Examples 1 and 2 described above.

5 to 7, the stent according to the present invention, including both the advantages of the V-structure and the advantages of the Y-structure, shows superior properties than the single structure of V or Y, and in a single structure stent Since the problems appearing are suppressed, there is an advantage that easy deployment is possible.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this application, terms such as "comprises" are intended to designate that the described feature, number, step, action, component, or combination thereof exists, but one or more other features or number, step, action, It should be understood that the possibility of the presence or addition of components, or combinations thereof, is not precluded in advance.

1 first structure
11 bend
12 space department
2 second structure
21 wire in the first spiral direction
22 wire in the second helix direction

Claims (7)

As a stent,
A first structure (1) in which the wire is bent in a zigzag shape and connected to each other by a bent portion (11), and
A wire 21 extending parallel to each other in a first helical direction and a wire 22 extending parallel to each other in a second helical direction opposite to the first helical direction are braided with each other, and a second structure (2) that is a connected structure,
Each of the first helical wire 21 and the second helical wire 22 of the second structure 2 crosses over the radially inward wire segments at a plurality of intersection points or a plurality of radially inward wires. passing under the outgoing wire segment,
In the rhombic space portion 12 formed by the four bent portions 11 of the first structure 1, the wire 21 in the first spiral direction of the second structure 2 and the second spiral direction A stent, characterized in that the wires (22) cross over. The method of claim 1,
Each of the first helical wire 21 and the second helical wire 22 of the second structure 2 alternately crosses above the radially inward wire segment and below the radially outward wire segment, Passing, stent. 3. The method of claim 1 or 2,
The wire 21 in the first helical direction of the second structure 2 is, at a plurality of intersections, the wire segment of the first structure 1 or the wire in the second helical direction of the second structure 2 ( 22) passing across the segment of the stent. 4. The method of claim 3,
The wire 21 in the first helical direction of the second structure 2 alternates between the wire segments of the first structure 1 and the segments of the second helical wire 22 of the second structure 2 A stent that crosses and passes by. The method of claim 1,
In the center of the space portion (12), the wire (21) in the first spiral direction and the wire (22) in the second spiral direction of the second structure (2) cross and pass. A method for manufacturing a stent, comprising:
A first step of forming a first structure (1) in which the wire is bent in a zigzag shape to be connected to each other by the bent portion (11), and
Wires 21 extending parallel to each other in a first spiral direction and wires 22 extending parallel to each other in a second spiral direction opposite to the first spiral direction are braided and connected a second step of forming a second structure (2) which is a structure to be
Each of the first helical wires 21 and the second helical wires 22 of the second structure 2 crosses over segments of the radially inwardly directed wires at a plurality of intersection points or the radially outwardly directed wires. formed to cross and pass under the wire segment,
In the rhombic space 12 formed by the four bent portions 11 of the first structure 1, the wire 21 in the first spiral direction of the second structure 2 and the second spiral direction A method of making a stent, allowing wires (22) to cross over. 7. The method of claim 6,
A method of manufacturing a stent, wherein after the first step of forming the first structure (1), a second step of forming the second structure (2) is performed.

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