Stent

Abstract

The present invention relates to a stent having a pull wire, wherein, when an outer tube is pulled at a lesion site, the pull wire in point contact therewith reduces resistance, allowing the outer tube to be pulled smoothly, and the pull wire prevents the thickness of a portion of the outer tube from being increased by the length of the pull wire, and, more specifically, to a stent comprising: a cylindrical body in which shape memory alloy wires are woven or crossed in a mesh form to have a hollow cylindrical shape, thereby forming a plurality of space portions between the wires, and which has a plurality of bent portions formed along the circumference thereof at both ends; and a pull wire provided at one end of the cylindrical body, wherein the pull wire consists of a single strand, wherein one end of the pull wire is tied to the wire of one bent portion to form a first knot portion, and the opposite end of the pull wire is woven through the space portions of the plurality of bent portions along the circumference of the cylindrical body and positioned adjacent to the first knot portion, and then is allowed to protrude outward from the cylindrical body, and the opposite end of the pull wire protruding outward from the cylindrical body is tied, thereby forming a second knot portion.

Description

stent

[0001] The present invention relates to a stent that can be easily removed from the lumen of the body through a pulling cord after a certain period of time has elapsed after being inserted into a lesion site that is narrowed or occluded in the lumen of the body.

[0002] In general, when a lesion occurs in the internal lumen of the body, such as the esophagus, duodenum, or bile duct, causing narrowing or occlusion, the inherent function of the internal lumen to move body fluids is reduced.

[0003] For this reason, a stent was inserted into the location of the lesion that was stenotic or occluded to expand the narrowed lumen of the body.

[0004] And, after the procedure was completed at the lesion site, the stent had to be removed from the lumen of the body after a certain period of time.

[0005] In this regard, Patent Document 1 provides a hook structure of a stent removal pull cord for forming a stent (10) comprising a cylindrical body (14) having a space (12) formed by interweaving or zig-zagging one or more shape memory alloy wires (11) with each other and having a plurality of bending ends (13) formed along the circumference at both ends, wherein the stent removal pull cord (20) is formed by forming a cylindrical pull cord (21) by interweaving the bending ends (13) of the cylindrical body (14) of the stent (10) in a zig-zag manner to form a circular band shape, and then tying the ends to form a hook (22).

[0006] However, in the case of patent document 1, as shown in FIG. 1, when the stent (10) is compressed to the outer tube (2a) of the stent delivery system (2) and mounted in the mounting space (2d') formed in the inner tube (2d), a pair of pulling lines (20) protruding outward from the stent (10) are in long contact with the inner surface of the outer tube (2a).

[0007] Due to this, when the stent (10) is inserted into the lesion site and the external tube (2a) is pulled, resistance may be generated by the pulling line (20) that is in contact with the surface, and the external tube (2a) may not be pulled properly. In other words, the stent (10) insertion may not be performed properly.

[0008] In addition, if the outer tube (2a) is not pulled well by the pull string (20) that is in contact with the surface and is pulled with a greater external force, the outer tube (2a) may be torn or cut.

[0009] And, since a pair of the above-mentioned pulling lines (20) were positioned between the outer tube (2a) and the stent (10), the thickness of a portion of the outer tube (2a) was thickened by the length (L) of the pair of the above-mentioned pulling lines (20).

[0010] Due to this, the outer tube (2a) with the increased thickness may experience resistance in the lumen of the body, making it difficult to move or making it difficult to pass through a narrow lesion area.

[0011] [Prior Art Literature]

[0012] [Patent Document]

[0013] Patent Document 1: Domestic Publication No. 10-2010-0119068

[0014]

[0015] Accordingly, the present invention aims to provide a stent having a different pulling cord from the prior art, which reduces resistance when pulling an external tube at a lesion site by a pulling cord that is in point contact, thereby allowing the external tube to be pulled well and facilitating stent placement, and which prevents a portion of the external tube from becoming thicker by the length of the pulling cord, thereby facilitating movement of the external tube in the lumen of the body and passage through a narrow lesion site.

[0016] In order to achieve the above object, the present invention provides a stent comprising: a cylindrical body in which wires made of a shape memory alloy are woven or crossed in a mesh shape in a hollow cylindrical shape to form a plurality of spaces between the wires, and a plurality of bends are formed along the circumference at both ends; and a pull cord installed at one end of the cylindrical body, and which is inserted into and expands a lesion site that is stenotic or occluded in the lumen of a body, wherein the pull cord is formed of a single strand, one end of the pull cord is tied to a wire of one bend to form a first knot portion, and the other end of the pull cord is woven into the space portions of the plurality of bends along the circumference of the cylindrical body and positioned adjacent to the first knot portion, and then protrudes outward from the cylindrical body, and the other end of the pull cord protruding from the outside of the cylindrical body is tied to form a second knot portion.

[0017] The present invention has the effect of making stent placement more smooth than in the past because the resistance is reduced by the second knot of the pulling line that makes point contact with the inner surface of the external tube when pulling the external tube from the lesion site, so that the external tube is pulled well.

[0018] Additionally, since it does not require a greater external force to be pulled, it has the effect of preventing the outer tube from being torn or cut by a greater external force.

[0019] In addition, since it is not necessary to use an external tube with a large diameter to reduce resistance due to the pulling cord, it has the effect of preventing the movement of the external tube in the lumen of the body and the difficulty in passing through a narrow lesion area due to an increase in diameter.

[0020] Since the present invention has a single, rather than a pair, pulling cord positioned between the outer tube and the stent, the thickness of the portion of the outer tube where the pulling cord is positioned does not become thicker than in the past.

[0021] That is, there is an effect in which the thickness of a part of the outer tube does not become longer or thicker than before by the length of the pull cord.

[0022] For this reason, the outer tube, which is not thicker than before, has the effect of reducing resistance in the lumen of the body during stent placement, making movement easier than before, and making passage through narrow lesion areas easier than before.

[0023] The present invention has the effect of removing the stent by pulling the second knot portion using a forceps or other forceps-like forceps after a certain period of time has elapsed after the stent has been placed in the lesion area.

[0024] For this reason, it has the effect of preventing forceps and other forceps from slipping on a pull string made of slippery material.

[0025] Since the present invention has a plurality of second knot portions formed on the pulling line, it has the effect of being able to hold a greater number of second knot portions with a forceps or other tweezers.

[0026] For this reason, by hooking a plurality of second knots on the forceps or other forceps member, the forceps or other forceps member has the effect of further preventing the forceps or other forceps member from slipping on the pulling line made of a slippery material, and also has the effect of increasing the pulling external force, thereby enabling the stent to be removed quickly.

[0027] In addition, since one of the plurality of second knots can be grabbed with a forceps or other forceps at any position of the pulling rope, there is an effect of being able to remove the stent by selecting a second knot at a position that is easy to remove the stent from among the plurality of second knots and pulling it with a forceps or other forceps.

[0028] Since the present invention forms a gap between one end of the cylindrical body of the stent and the adjacent second knot portion, it has the effect of preventing the entrance of the stent from being caught on the second knot portion and not being expanded to its original state when the compressed stent is expanded.

[0029] For this reason, there is an effect in which the lesion area is smoothly expanded by the stent of the present invention.

[0030] Figures 1 and 2 are a diagram and a partial enlarged view of a conventional stent in use.

[0031] Figures 3 and 4 are a front view and a plan view of a stent according to an embodiment of the present invention.

[0032] Figures 5 to 7 are partial enlarged views of Figure 3 and diagrams showing the process of forming the first knot.

[0033] Figures 8 to 10 are partial enlarged views of Figure 3 and diagrams showing the process of forming the second knot portion.

[0034] Figure 11 is a diagram showing the use state of a stent according to an embodiment of the present invention, showing why a gap is formed between the cylindrical body and the second knot portion.

[0035] Fig. 12 is a partially enlarged cross-sectional view of Fig. 4;

[0036] Figures 13 to 21 are diagrams showing the state of use of a stent according to an embodiment of the present invention.

[0037] Accordingly, the embodiments of the present invention as described above will be described in detail based on the attached drawings as follows.

[0038] As illustrated in FIGS. 1 to 21, a stent (1000) according to an embodiment of the present invention is inserted into a lumen (1) of a body, such as the esophagus, duodenum, biliary tract, etc., by a stent delivery system (2), and is used to expand a lesion site (1a) that is narrowed or occluded in the lumen (1).

[0039] Here, the stent delivery system (2) includes a first handle (2b) connected to an outer tube (2a) that moves along the lumen (1) of the body; a second handle (2c) that moves from the first handle (2b); an inner tube (2d) that is connected to the second handle (2c) and inserted so as to be movable inside the outer tube (2a), and has a mounting space (2d') formed on one side thereof in which the stent (1000) of the present invention is mounted by being compressed on the outer tube (2a); and a guide tip (2e) that is connected to the inner tube (2d) and exposed from the outer tube (110).

[0040] The above stent (1000) is composed of a cylindrical body (100) in which wires (110) made of a shape memory alloy are woven or crossed in a mesh shape in a hollow cylindrical shape to form a plurality of spaces (120) between the wires (110), and a plurality of bent portions (130) are formed along the circumference at both ends, and a pulling line (200) installed at one end of the cylindrical body (100).

[0041] The above-mentioned pulling rope (200) is composed of a single strand and is made of nylon material, etc., and one end of the pulling rope (200) is tied to a wire (110) of a bending portion (130) to form a first knot portion (210).

[0042] The process of forming the first knot portion (210) will be described in detail as shown in FIGS. 6 and 7. The first knot portion (210) is formed by one side of a pull cord (200) passing through a space (120) of a bend (130) and twisting to form at least one loop penetrating the wire (110), and then passing the loop through one side of the pull cord (200), the loop becomes smaller and one side of the pull cord (200) is tied to the wire (110).

[0043] The above-mentioned pulling rope (200) is positioned adjacent to the first knot portion (210) by weaving one side of the opposite side of the pulling rope (200) into the space portion (120) of a plurality of bend portions (130) along the circumference of the cylindrical body (100), and then protrudes outward from the cylindrical body (100), and the other side of the pulling rope (200) protruding from the outside of the cylindrical body (100) is tied to form the second knot portion (220).

[0044] The process of forming the second knot portion (220) will be described in detail as shown in FIGS. 9 and 10. The second knot portion (220) is formed by twisting one side of the opposite side of the pull cord (200) protruding from the outside of the cylindrical body (100) to form at least one loop, then passing the loop through the opposite side of the pull cord (200), causing the loop to become smaller and tying the opposite side of the pull cord (200).

[0045] Here, the second knot portion (220) is formed in a plurality at predetermined intervals along the length of the pulling line (200) protruding from the outside of the cylindrical body (100).

[0046] In addition, a gap (230) is formed between one end of the cylindrical body (100) and the adjacent second knot portion (220).

[0047] As illustrated in FIG. 11, the reason why the gap (230) is formed will be described in detail. When the stent (1000) of the present invention is compressed to the outer tube (2a) of the stent delivery system (2) and mounted in the mounting space (2d') of the inner tube (2d), the length (L1) of the diameter of the cylindrical body (100) is formed to be shorter than the length (L2) between one end of the cylindrical body (100) and the adjacent second knot portion (220), and when the stent (1000) of the present invention is implanted in the lesion site (1a), the length (L1) of the diameter of the cylindrical body (100) is formed to be longer than the length (L2) between one end of the cylindrical body (100) and the adjacent second knot portion (220). At this time, the entrance of the cylindrical body (100) that is expanded, i.e., In order to prevent the entrance of the stent (1000) from being caught on the second knot portion (220), a gap (230) is formed between one end of the cylindrical body (100) and the adjacent second knot portion (220).

[0048] Here, the above gap (230) is formed to be 3 mm to 10 mm.

[0049] The operation of the stent (1000) according to an embodiment of the present invention is described as follows.

[0050] As illustrated in FIGS. 1 to 21, the stent (1000) of the embodiment of the present invention is compressed to the outer tube (2a) of the stent delivery system (2) and mounted in the mounting space (2d') of the inner tube (2d).

[0051] Then, the second knot (220) of the pulling line (200) protruding outwardly of the stent (1000) is in point contact with the inner surface of the outer tube (2a), and since the pulling line (200) is positioned between the outer tube (2a) and the cylindrical body (100) of the stent (1000) as one, i.e., one strand, the thickness of the part of the outer tube (2a) where the pulling line (200) is positioned does not increase.

[0052] Of course, even if the above-mentioned pulling line (200) is positioned inside the cylindrical body (100) of the stent (1000) rather than outside the cylindrical body (100) of the stent (1000), since the pulling line (200) is formed of one, i.e., one strand, the thickness of a portion of the outer tube (2a) where the pulling line (200) is positioned does not increase.

[0053] Then, after confirming the location of the above lesion site (1a) with an endoscope, the first and second handles (2b) (2c) of the stent delivery system (2) are advanced to advance the inner and outer tubes (2d) (2a) along the lumen (1) of the body.

[0054] Here, since the thickness of the outer tube (2a) is not increased by the single-stranded pulling line (200), as shown in FIG. 16, the outer tube (2a) is easily moved to the lesion site (1a) by reducing the resistance, that is, the snagging that occurs in the lumen (1) of the body when moving, and as shown in FIG. 17, the outer tube (2a) is easily passed through the narrow lesion site (1a) by reducing the snagging that occurs when passing through the narrow lesion site (1a).

[0055] As shown in Fig. 18, since the second knot portion (220) is in point contact with the inner surface of the outer tube (2a), the outer tube (2a) is easily pulled by reducing the resistance, i.e., the snag that occurs when pulling the outer tube (2a) through the first handle (2b) at the lesion site (1a).

[0056] For this reason, the stent (1000) of the present invention, which was compressed to the external tube (2a), is expanded without delay.

[0057] As illustrated in Fig. 19, since a gap (230) is formed between one end of the cylindrical body (100) and the adjacent second knot portion (220), the entrance of the expanding cylindrical body (100), i.e., the entrance of the stent (1000), does not get caught on the second knot portion (220).

[0058] For this reason, the stent (1000) of the present invention is easily expanded to expand the lesion site (1a).

[0059] As illustrated in Fig. 20, after a stent (1000) has been inserted into a lesion site (1a) that is narrowed or occluded in the lumen (1) of the body, it becomes necessary to remove it after a certain period of time. At this time, one of the plurality of second knot portions (220) of the pulling line (200) is grabbed and pulled with a forceps member (3) such as forceps.

[0060] Then, as the first knot portion (210) fixed to the bend portion (130) of the stent (1000) is pulled by the second knot portion (220) being pulled, the entrance of the stent (1000) is compressed, and the stent (1000) can easily come out of the lumen (1) of the body.

[0061] As illustrated in Fig. 21, the stent (1000) can be removed from the lumen (1) of the body by pulling at least two second knot portions (220) with a forceps member (3) such as the above forceps.

[0062] Although the present invention has been described and illustrated with specific preferred embodiments as examples, the present invention is not limited to the above embodiments, and various changes and modifications may be made by a person skilled in the art to which the invention pertains within a scope that does not depart from the spirit of the present invention.

[0063] [Explanation of symbols]

[0064] 100: Cylindrical body 110: Wire

[0065] 120: Space 130: Bend

[0066] 200: Pull rope 210: First knot

[0067] 220: Second knot 230: Spacing

[0068] 1000: Stent

Claims

1. A cylindrical body (100) in which wires (110) made of a shape memory alloy are woven or crossed in a mesh-like manner in a hollow cylindrical shape, and a plurality of space portions (120) are formed between the wires (110), and a plurality of bend portions (130) are formed along the circumference at both ends, It consists of a pulling line (200) installed at one end of the above cylindrical body (100), In a stent that is inserted into and expanded at a lesion site (1a) that is narrowed or occluded in the lumen (1) of the body, The above-mentioned pulling rope (200) is composed of a single strand, and one end of the pulling rope (200) is tied to a wire (110) of a bending portion (130) to form a first knot portion (210). The opposite side of the above-mentioned pulling rope (200) is woven into the space (120) of a number of folded parts (130) along the circumference of the cylindrical body (100) and positioned adjacent to the first knot part (210), and then protrudes outward from the cylindrical body (100). A stent characterized in that a second knot portion (220) is formed by tying one end of the opposite side of a pulling string (200) protruding from the outside of the cylindrical body (100).

2. In paragraph 1, A stent characterized in that the second knot portion (220) is formed in a plurality at predetermined intervals along the length direction of the pulling line (200) protruding from the outside of the cylindrical body (100).

3. In paragraph 1, A stent characterized in that a gap (230) is formed between one end of the cylindrical body (100) and an adjacent second knot portion (220).

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