KR100548781B1 - A cylindrical stent - Google Patents

Abstract

The present invention relates to a cylindrical stent composed of a wire and having a longitudinal axis, wherein a plurality of peaks 1c and valleys 1b are connected to the linear portions 1a along the circumferential surface. The reference turns (1) having a one-turn in a zigzag and having a plurality of reference turns are arranged without crossing points at intervals equal to the height (h) of the reference turn along the cylindrical longitudinal direction, and [ii] The connecting turns 2 connecting the plurality of reference turns to each other in a mesh form by winding the linear portions 1a of the reference turns overlapping while being arranged in the left and right inclined directions are turned in the reference turn in the left and right inclination directions. It is characterized by consisting of a plurality of connecting turns arranged at the same interval as the distance (d) between the straight portion. The present invention is provided with a connection turn (2) for connecting the reference turns (1) and excellent flexibility, the connection turn (2) is wound around the reference turn (1) is also excellent in expandability. As a result, the lumen is in close contact with the deformation curve of the lumen, and even when bending, it is possible to maintain the cylindrical shape as it is, to improve the flow of blood vessels, etc., and to minimize the formation of fixing wire.

Stent, Medical Device, Cylindrical, On Coil, Reference Turn, Connecting Turn, Spacing, Elasticity

Description

Cylindrical stent {A cylindrical stent}             

1 is a perspective schematic view of the stent of the present invention

Figure 2 is an enlarged view showing a unit cell of the stent of the present invention

Figure 3 is an enlarged view showing the reference turn of the stent of the present invention

4 to 6 are views for explaining a method of manufacturing the stent of the present invention

7 and 8 are views showing the connection state of the reference turns in the conventional stent

※ Explanation of main parts in drawings

1: reference turn 2: connection turn

1a: straight portion of the reference turn 1b: valley portion of the reference turn

1c: peak portion of the reference turn d: distance between the straight portions of the reference turn

h: Height of reference turn H: Spacing between reference turns

10: jig for manufacturing stent 11: 1st reference pin 12: 2nd reference pin

The present invention relates to a luminal medical device, and more particularly, to a self-expansion type medical device (hereinafter referred to as a "stent") that expands when the lumen of blood vessels or esophagus is constricted. More specifically, the present invention relates to a stent that is not only able to be reduced to a minimum size but also has excellent expandability and excellent flexibility while bending in a curved shape of the lumen.

In general, due to diseases occurring in the human body, the lumens in the human body may become narrowed and may be in a state in which no function may occur in severe cases. For example, when the lumen is narrowed, esophageal cancer may cause narrowing of the esophagus, when atherosclerosis does not allow a smooth blood circulation, or when a track through which bile from the liver flows may be narrowed.

As the lumen is confined as described above, food, blood, or bile cannot flow smoothly. Therefore, the constricted lumen should be expanded to maintain the passage. In this case, for example, as a method for extending and maintaining the constricted passage, A stent is inserted into the lumen.

Such stents generally have a cylindrical structure in overall shape, and have an elastic force so that the stent can be contracted by applying an external force, and when the external force is removed, the self-expanding method is widely used.

The self-expandable stent has various characteristics, that is, expandability to expand the lumen, flexibility to adapt flexibly while maintaining the curved shape of the lumen at the bent portion of the lumen, and shrinkage to be reduced to a constant diameter. If you have sex, you will be able to function properly as a stent.

If the stent lacks the expandability of the characteristics of the stent, it is easy to move from the initial insertion position of the lumen, if the lack of flexibility, when the stent expands in the bent portion of the lumen, it is inadequate in the bent portion of the lumen, shrinkage If this is insufficient, the size of the inserting device for inserting the stent will increase.

Therefore, a number of stents having the above functions have been developed, and these stents can be largely divided into spiral stents and zigzag stents.

Representative of the spiral stents, the filament having a unit length spirally wound along the cylindrical wall surface and reciprocating both ends in a zigzag form again and intersecting with each other to form a mesh to have an overall cylindrical shape. Such a spiral stent can be reduced to a small diameter, so that the flexibility is excellent while the flexibility is greatly reduced in expandability.

On the other hand, the Republic of Korea Patent Publication No. 1998-67399 and the like, a plurality of turns in a zigzag to form a peak portion and a valley portion connecting the filament by a plurality of straight portions and a plurality of bending points, and the one-turn of The valley portion presents a stent formed by twisting the corresponding peak portions of the one turn and the neighboring turns with each other as shown in FIGS. 7 and 8.

However, the conventional stent is excellent in expandability to expand the narrowed lumen, but also inferior in flexibility, it is difficult to shrink to a small size, there is a disadvantage that does not maintain the bent shape in the bent portion of the lumen.

The present invention has been proposed to solve the above problems, an object of the present invention is to reduce the size to a minimum size having a connecting turn to connect to each other while wrapping the reference turns, excellent in expandability and flexibility bending the lumen It is to provide a cylindrical stent that maintains the cylindrical shape well to smooth the flow of blood, etc. in the jin site and be in close contact with the inner wall of the lumen while bending in the bent shape of the lumen.

Cylindrical stent of the present invention for achieving such a problem, the [Zig] zigzag while the wire has a plurality of peaks (1c) and valleys (1b) connected to the straight portion (1a) along the circumferential surface [00] A linear portion of the reference turns overlapping while being arranged in the left and right inclination directions of the plurality of reference turns and the reference turns (1) which are formed while rotating one by one in the longitudinal direction of the cylinder without crossing each other. In the cylindrical stent having a plurality of connecting turns that connect the plurality of reference turns to each other in a mesh form by winding (1a) onto a coil and having a longitudinal axis, an arrangement interval of the reference turns is the height of the reference turn ( Same as h), and the arrangement interval of the connection turns is equal to the distance d between the straight portions of the reference turn.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Cylindrical stent of the present invention includes a plurality of reference turns (1) formed by rotating one wire in a zigzag while having a plurality of bending points along the circumferential surface of the wire having a unit length as shown in the perspective schematic of FIG.

The reference turn has a plurality of peak portions 1c and valley portions 1b as shown in FIG. 3, and the peak portions 1c and valley portions 1b are formed by straight portions 1a inclined left and right. It has a connected structure. The reference turns 1 are arranged without intersections at intervals equal to the height h of the reference turns along the cylindrical longitudinal direction.

On the other hand, the cylindrical stent of the present invention is arranged in the direction of the left and right inclination of the reference turn as shown in the perspective schematic view of Figure 1 (arranged along the straight portion of the reference turn) while overlapping the straight portion (1a) of the reference turn It comprises a plurality of connecting turns (2) which are wound around the routine to connect the plurality of reference turns to each other. The connection turns 2 are arranged at the same interval as the distance d between the reference turn straight portions 1a.

The cylindrical stent of the present invention forms the unit cell as shown in FIG. 2 by the reference turns 1 and the connection turns 2 described above.

In the unit cell of FIG. 2, the connection turns 2 connecting the reference turns 1 arranged in a non-crossed state in a coil shape are connected to a mesh, thereby greatly improving the flexibility of the stent. Because of this, the stent can be reduced to a smaller size, and even in the bent portion of the lumen, the stent can maintain the original shape, thereby improving the flow of blood and the like.

In addition, the present invention is excellent in expandability because the connecting turns (2) are wound on the coil of the straight portion (1a) of the reference turn overlapping this. It is preferable that the number of times that the connecting turn 2 winds the straight portion 1a of the reference turn is 2-10 times. The wire constituting the reference turn 1 and the connection turn 2 is preferably nitanol, which is a shape memory alloy.

Looking at one example of a method for producing a cylindrical stent of the present invention.

First, as shown in FIG. 4, one reference turn 1 is formed by zigzag a wire along the first reference pin 11 and the second reference pin 12 of the stent fabrication jig 10. Repeating the operation of forming another reference turn (1) in the same manner as described above at a position spaced apart from the reference turn formed as shown in the jig 10 by a distance (H) equal to the reference turn height (h) A plurality of reference turns are formed along the length of the cylinder and arranged without intersections.

Next, as shown in Figs. 5 and 6 to form a connecting turn 2 for connecting the straight portion (1a) of the reference turn in the left and right inclined direction. At this time, the interval between the connection turns (2) is adjusted to be equal to the distance (d) between the reference turn linear portion, and the straight portion (1a) of the reference turn overlapping the connection turn (2) is wound by the connection turn (2).

When the formation of the connecting turn 2 is completed, the wire is positioned as the first reference pin 11 of the jig 10. In this case, when the wire is knotted, the thin wire work of the stent is completed.

In the present invention, since the knot of the connecting turn 2 serves as a fixing wire for fixing the stent to the lumen, there is an advantage of minimizing the production and attachment of the fixing wire separately.

Next, the thin stent is completed, the stent is heated for 10-20 minutes in a heating oven set at 400 ° C.-600 ° C. together with the jig 10 for stent fabrication, and then slowly cooled at room temperature for 30 minutes-4 hours, and the stent is Separating from the jig 10, and finishing work is completed the manufacture of the stent.

In the present invention, the heating and slow cooling conditions for producing the stent are not particularly limited.

Cylindrical stent of the present invention has a connection turn (2) for connecting them in a mesh shape while wrapping the reference turn (1) in the unit cell is very excellent in flexibility and expandability. As a result, it can be reduced to a minimum size, the circular shape can be maintained at the bent portion of the lumen, and the adhesion to the bent portion of the lumen is excellent. In addition, the present invention can minimize the number of separate fixing wires.

Claims (3)

[Ⅰ] The reference turns 1, which are formed while the wire is rotated zigzag and have a plurality of peak portions 1c and valley portions 1b connected to the straight portions 1a along the circumferential surface thereof, are formed in the cylindrical longitudinal direction. A plurality of reference turns arranged without a cross point along each other and [ii] the plurality of reference turns mesh by winding the linear portions 1a of the reference turns overlapped while being arranged in the left and right inclined directions of the reference turns onto a coil. In a cylindrical stent having a plurality of connecting turns connected to each other in a form and having a longitudinal axis, an arrangement interval of the reference turns is equal to a height h of the reference turns, and an arrangement interval of the connection turns is a reference turn. Cylindrical stent, characterized in that the same as the distance (d) between the straight portions of. The cylindrical stent of claim 1, wherein the wire is made of nitanol, which is a shape memory alloy. 2. The cylindrical stent according to claim 1, wherein the connecting turn (2) surrounds the straight portions (1a) of the reference turn overlapping with each other two to ten times.

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