Covered stent

Abstract

To provide a covered stent which prevents a lumen in the body from being repeatedly punctured or causing friction.SOLUTION: The covered stent 1000 includes a cylindrical stent in which a plurality of space portions 120 are formed between wires 110 made of a shape memory alloy by weaving or crossing the wires 110 in a hollow cylindrical mesh shape and a plurality of bent portions 130 are formed at both ends of the cylindrical stent 100 along a circumferential direction, a coating portion 200 in which first and second PTFE tapes respectively formed on inner and outer surfaces of the cylindrical stent 100 are bonded to each other by heating and pressing, and a PTFE protective member 300 which is located at both ends of the cylindrical stent, has a cylindrical shape with an open center, has a groove formed in a thickness portion to surround the bent portion by inserting an end portion of the cylindrical stent thereinto, and is bonded to an outer side of the coating portion by heating and pressing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a covered stent that is operated on and expanded at a stenotic or occlusive lesion site in a lumen of the body. [Background technology]

[0002] Generally, when a stenosis or obstruction occurs in a lumen of the human body, such as the urethra or pancreatic duct, the inherent function of the lumen as a lumen for transporting bodily fluids is impaired.

[0003] For this reason, a stent is inserted at the location of the stenosis or occlusion to expand the narrowed lumen in the body.

[0004] In this regard, Patent Document 1 provides a stent manufactured by a method for manufacturing an adhesive stent for artificial blood vessels, characterized by the steps of: manufacturing a stent having a hollow cylindrical body formed by weaving superelastic shape memory alloy wires in a crosswise manner; winding an artificial blood vessel diagonally around an SUS rod to form an inner artificial blood vessel layer made of PTFE, inserting the stent on the outside of the stent, winding the artificial blood vessel diagonally around the stent to form an outer artificial blood vessel layer made of PTFE, and then inserting a silicone tube to prepare for bonding; and fixing the prepared SUS rod inside a vacuum heating device, and then using a vacuum operation, the inner and outer artificial blood vessel layers located on the inside and outside of the stent enclose the stent from the inside and outside, adsorbing each other toward the stent, while heating the inner and outer artificial blood vessel layers to thermally fuse with each other and bond them together to form an integrated bond with the stent.

[0005] However, in the case of Patent Document 1, as shown in Figure 1, there is a risk that the numerous bent portions 12 formed around the circumference at both ends of the stent 10 may not be properly coated with the inner and outer PTFE artificial blood vessel layers 31, 32, which may result in the sharp bent portions 12 being exposed from the inner and outer PTFE artificial blood vessel layers 31, 32.

[0006] Therefore, as shown in Figure 2, when a stent 10 having inner and outer PTFE artificial vascular layers 31, 32 formed thereon is applied to a stenotic or occlusive lesion site 1a in a lumen 1 inside the body, the sharp bent portion 12 may repeatedly puncture the lumen 1 inside the body or cause friction, resulting in the risk of irritation or inflammation. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Publication No. 10-2015-0052719 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the present invention has been made to solve such problems of the conventional art, and its purpose is to provide a covered stent that differs from conventional ones in that the sharp bends of a covered stent having a PTFE coating are covered with a PTFE protective member, thereby preventing exposure of the sharp bends that may occur when the PTFE coating is not properly coated, and preventing the sharp bends from repeatedly puncturing the internal lumen of the body or causing friction at the lesion site. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the present invention provides a covered stent comprising: a cylindrical stent in which wires made of a shape memory alloy are woven or crossed into a hollow cylindrical mesh to form numerous spaces between the wires, and in which numerous bent portions are formed around the circumference at both ends; a covering portion formed by first and second PTFE tapes formed on the inner and outer surfaces of the cylindrical stent and bonded to each other by heating and pressing; and PTFE protective members located on both ends of the cylindrical stent, each cylindrical with an open center, having grooves formed in its thickness portion into which the ends of the cylindrical stent are fitted to surround the bent portions, and bonded to the outside of the covering portion by heating and pressing. [Effects of the Invention]

[0010] According to the present invention, the sharp bends of the covered stent having a PTFE coating are covered with a PTFE protective member, which has the effect of preventing the exposure of the sharp bends that may occur when the PTFE coating is not properly applied.

[0011] This has the effect of preventing the sharp bends of the covered stent from repeatedly piercing or rubbing the body lumen at the lesion site with the PTFE protective member, and also has the effect of preventing irritation and inflammation.

[0012] The present invention has the effect of covering the sharp bends formed at both ends of the covered stent with pre-fabricated PTFE protective members.

[0013] In addition, after fitting a portion of the PTFE protective member inside or outside the cylindrical stent, the remaining portion can be bent to cover the sharp bends formed at both ends of the covered stent with the PTFE protective member.

[0014] That is, there is an advantage that the PTFE protective members can be attached to both ends of the covered stent in various ways.

[0015] The present invention has the advantage that the second PTFE tape formed in a spiral shape prevents the hook portions and parts of the intersection portions formed by braiding or crossing the wire from being fixed to the first and second PTFE tapes of the coating portion.

[0016] As a result, the hook portions and a portion of the crossing portion are free, and the covered stent has adaptability, which has the effect of easily deforming into a curved shape to fit the curved lumen inside the body.

[0017] The present invention has the advantage that the lesion site or the lumen of the body is inserted into the space of the covered stent that is not closed by the second PTFE tape formed in a spiral shape, so that the covered stent is engaged with the lesion site and the lumen of the body where it is inserted into the space.

[0018] This has the effect of further preventing the covered stent from coming off the lesion site due to shaking of the human body or external forces generated outside. [Brief explanation of the drawings]

[0019] [Figure 1] 1A and 1B are a front view and a view showing a state of use of a conventional stent. [Figure 2] 1A and 1B are a front view and a view showing a state of use of a conventional stent. [Figure 3] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 4] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 5] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 6] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 7] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 8] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 9] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 10] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 11] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 12]1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 13] 1A-1C are a front view, a partial enlarged view, and a detailed view of a covered stent according to an embodiment of the present invention. [Figure 14] 1 is a diagram illustrating a state in which a covered stent according to an embodiment of the present invention is used. [Figure 15] 1 is a diagram illustrating a state in which a covered stent according to an embodiment of the present invention is used. [Figure 16] 1A and 1B are a front view, a partially enlarged view, and a detailed view of a covered stent according to a first modified example of an embodiment of the present invention. [Figure 17] 1A and 1B are a front view, a partially enlarged view, and a detailed view of a covered stent according to a first modified example of an embodiment of the present invention. [Figure 18] 1A and 1B are a front view, a partially enlarged view, and a detailed view of a covered stent according to a first modified example of an embodiment of the present invention. [Figure 19] 1A and 1B are a front view, a partially enlarged view, and a detailed view of a covered stent according to a first modified example of an embodiment of the present invention. [Figure 20] 1A and 1B are a front view, a partially enlarged view, and a detailed view of a covered stent according to a first modified example of an embodiment of the present invention. [Figure 21] FIG. 1 is a view showing a state in which a covered stent according to a first modified example of an embodiment of the present invention is used. [Figure 22] FIG. 1 is a view showing a state in which a covered stent according to a first modified example of an embodiment of the present invention is used. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0021] As shown in Figures 3 to 15, a covered stent 1000 according to an embodiment of the present invention is inserted into an internal cavity 1 of the human body, such as the urethra or pancreatic duct, via a stent delivery system, and is used to expand a stenosis or obstruction lesion 1a occurring in the internal cavity 1.

[0022] Here, the stent delivery system includes a first handle connected to an outer tube that moves along a lumen 1 in the body, a second handle that moves from behind the first handle, an inner tube that is connected to the second handle and inserted so as to be able to move inside the outer tube, and has an attachment space formed on one side in which the stent of the present invention is crimped and attached to the outer tube, and a guide tip that is connected to the inner tube and exposed from the outer tube.

[0023] The covered stent 1000 includes a cylindrical stent 100 in which wires 110 made of shape memory alloy are woven or crossed into a hollow cylindrical mesh, forming a number of spaces 120 between the wires 110, and hook portions 140 and crossing portions 150 are formed around the spaces 120, and a number of bent portions 130 are formed along the circumference at both ends.

[0024] Here, the hook portion 140 and the crossing portion 150 are formed by braiding or crossing the wire 110 .

[0025] The covered stent 1000 includes a covering portion 200 formed by bonding first and second PTFE (polytetrafluoroethylene) tapes 210 and 220 formed on the inner and outer surfaces of the cylindrical stent 100 by heating and pressing.

[0026] Here, the coating portion 200 is formed on the cylindrical stent 100 by winding a first PTFE tape 210 around the outer surface of a jig by taping, inserting the jig into the inside of the cylindrical stent 100, winding a second PTFE tape 210 around the outer surface of the cylindrical stent 100 by taping, and heating and pressing the cylindrical stent 100 with the jig inserted inside until the first and second PTFE (polytetrafluoroethylene) tapes 210 and 220 are adhered to each other.

[0027] The first and second PTFE (polytetrafluoroethylene) tapes 210 and 220 are formed on the entire inner and outer surfaces of the cylindrical stent 100 , and the numerous spaces 120 of the cylindrical stent 100 are closed by the coating portion 200 .

[0028] The covered stent 1000 is positioned at both ends of the cylindrical stent 100, has a cylindrical shape with an open center, has a ring-shaped groove 310 formed in the thickness part into which the ends of the cylindrical stent 100 are fitted and surrounds the bending portion 130, and includes a pair of protective members 300 made of PTFE (polytetrafluoroethylene) that are bonded to the outside of the covering portion 200 by heating and pressing.

[0029] As shown in Figures 8 and 9, the PTFE protective member 300 is positioned at both ends of the cylindrical stent 100 on which the coating portion 200 is formed, and the ends of the cylindrical stent 100 are fitted into the groove 310 to enclose the bent portion 130.

[0030] In addition, a jig is inserted into the cylindrical stent 100 having the PTFE protective member 300 attached to both ends, and then the PTFE protective member 300 and the coating portion 200 are heated and pressed until they are adhered to each other, thereby completing the stent 1000 according to an embodiment of the present invention.

[0031] As shown in Figures 10 and 11, the PTFE protective member 300 is cylindrical and open in the center. At both ends of the cylindrical stent 100, a portion of the PTFE protective member 300 is fitted into the interior of the cylindrical stent 100, and the remaining portion is bent outward to cover both ends of the cylindrical stent 100 so that the ends of the cylindrical stent 100 are fitted and grooves 310 surrounding the bent portions 130 are formed. After that, the PTFE protective member 300 may be bonded to the coating portion 200 by heating and pressing with a jig inserted inside the cylindrical stent 100.

[0032] As shown in Figures 12 and 13, the PTFE protective member 300 is cylindrical and open in the center. At both ends of the cylindrical stent 100, a portion is fitted to the outside of the cylindrical stent 100, and the remaining portion is bent inward to cover both ends of the cylindrical stent 100 so that the ends of the cylindrical stent 100 are fitted and grooves 310 surrounding the bent portions 130 are formed. After that, the PTFE protective member 300 may be bonded to the coating portion 200 by heating and pressing with a jig inserted inside the cylindrical stent 100.

[0033] Next, the operation of the covered stent 1000 according to the embodiment of the present invention will be described.

[0034] As shown in Figures 14 and 15, the covered stent 1000 according to an embodiment of the present invention is inserted into a body lumen 1 such as the urethra or pancreatic duct of a human body via a stent delivery system, and dilates a stenotic or obstructive lesion 1a occurring in the lumen 1.

[0035] Here, even if the bent portion 130 of the covered stent 1000 is not completely covered by the first and second PTFE tapes 210, 220 of the coating portion 200, it is covered by the PTFE protective member 300, and therefore does not puncture or cause friction in the lumen 1 inside the body.

[0036] As shown in Figures 16 to 22, the second PTFE tapes 220 of the covered stent 1000 according to the first modified embodiment of the present invention are spirally formed on the outer surface of the cylindrical stent 100 so as to form a gap d between them, and are formed to cover both ends of the outer surface of the cylindrical stent 100.

[0037] Here, the space 120 located where the first and second PTFE tapes 210 and 220 overlap is closed, and the space 120 located where the first and second PTFE tapes 210 and 220 do not overlap is not closed.

[0038] Furthermore, the hook portion 140 and the crossing portion 150 located in the portion where the first and second PTFE tapes 210 and 220 do not overlap are not fixed to the covering portion 200 and are in a free state.

[0039] As shown in Figures 21 and 22, the covered stent 1000 according to the first variant of the embodiment of the present invention is inserted into an internal lumen 1 of the human body, such as the urethra or pancreatic duct, via a stent delivery system, and expands the stenotic or obstructive lesion 1a occurring in the lumen 1.

[0040] Furthermore, since the hook portion 140 and the intersection portion 150 located in the portion where the first and second PTFE tapes 210, 220 do not overlap are not fixed to the coating portion 200, the shape of the space portion 120 changes as the hook portion 140 and the intersection portion 150 change shape in response to the curved shape of the inner cavity 1 inside the body.

[0041] As a result, the covered stent 1000 is deformed into a curved shape to match the curved shape of the lumen 1 inside the body.

[0042] Furthermore, the space 120 located in the portion where the first and second PTFE tapes 210 and 220 do not overlap is not closed, so that the cavity 1 and the lesion site 1a in the body are inserted into the space 120.

[0043] As a result, the covered stent 1000 is locked in the lumen 1 and the lesion site 1a inside the body inserted into the space 120.

[0044] Although the present invention has been illustrated and described above by way of examples of specific preferred embodiments, the present invention is not limited to these embodiments, and various changes and modifications can be made by those having ordinary skill in the art to which the invention pertains without departing from the spirit of the present invention. [Explanation of symbols]

[0045] 100 Cylindrical stent 110 Wire 120 Space section 130 Bend section 140 Hook part 150 Intersection 200 Coating section 210 First PTFE Tape 220 Second PTFE Tape 300 Protective material 310 Groove 1000 Covered Stents

Claims

1. A cylindrical stent (100) in which wires (110) made of a shape memory alloy are woven or crossed into a hollow cylindrical mesh to form a number of spaces (120) between the wires (110) and a number of bent portions (130) are formed along the circumference at both ends; a coating portion (200) formed by bonding first and second PTFE (polytetrafluoroethylene) tapes (210) and (220) formed on the inner and outer surfaces of the cylindrical stent (100) by heating and pressing; a protective member (300) made of PTFE (polytetrafluoroethylene), which is positioned at each end of the cylindrical stent (100), has a cylindrical shape with an open center, has a groove (310) formed in its thickness portion so that the end of the cylindrical stent (100) is fitted therein and surrounds the bent portion (130), and is bonded to the outside of the coating portion (200) by heating and pressing; A covered stent comprising:

2. The protective member (300) is cylindrical with an opening in the center, and is partially fitted into the inside or outside of the cylindrical stent (100) at both ends of the cylindrical stent (100); 2. The covered stent according to claim 1, wherein the remaining portion is folded to cover both ends of the cylindrical stent (100) so that the ends of the cylindrical stent (100) are fitted together to form grooves (310) surrounding the bent portions (130), and the covered portion (200) is bonded to the outside of the coated portion (200) by heating and pressing.

3. 2. The covered stent according to claim 1, wherein the second PTFE tape (220) is spirally formed on the outer surface of the cylindrical stent (100) so as to form a gap (d) between the second PTFE tape (220) and is formed to cover both ends of the outer surface of the cylindrical stent (100).

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