Stent storage jig and stent delivery system

Abstract

To provide a stent storage tool that can easily store a stent in a stent delivery system.SOLUTION: A stent storage tool 60 is used for a stent delivery system 1. The stent delivery system 1 comprises: an external cylinder 20 whose inside on its tip side can store a stent 10 in a diameter reduction state; an inner member 30 that is disposed inside the external cylinder 20 so as to be movable forward and backward in an axial direction and is capable of being arranged in a state in which its tip protrudes outside more than the tip side in the axial direction of the external cylinder 20; and a tip chip 40 provided at a tip of the inner member 30. The stent storage tool 60 comprises: a core member 614 outside which the stent 10 is disposed and inside which a storage part 618 capable of storing the tip chip 40 is provided; a guide member 62 that is disposed between the core member 614 and the external cylinder 20 and is formed in a cylindrical shape having a taper inner surface 622a; and a coupling member 63 for coupling the core member 614 with the guide member 62 in a state in which their axial directions agree with each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a stent storage jig used for a stent delivery system for implanting a stent in a living body and a stent delivery system including the same.

Background Art

[0002] Conventionally, in stenotic diseases (such as tumors and inflammations) of biological conduits such as blood vessels and digestive tracts, a treatment has been performed in which a stent, which is a mesh-like cylindrical member, is implanted in a stenotic portion to expand the stenotic portion and maintain an open state. Generally, a stent is stored in a radially compressed state in a thin tubular member called a delivery system and is transported to a stenotic portion using an endoscope. After the delivery system is brought close to the stenotic portion, the stent is released from the delivery system and the stent is implanted in the stenotic portion.

[0003] A delivery system generally includes an outer sheath (outer cylinder) that stores a stent in a diameter-reduced state at its tip, a guide wire guiding tube (inner member) disposed inside the outer sheath and having a through-hole through which a guide wire can be inserted, and a tip provided at the tip of the guide wire guiding tube. The delivery system is inserted into a living body along a guide wire to deliver the stent to a stenotic portion.

[0004] A stent is stored in the outer sheath of the delivery system. Since the inner diameter of the outer sheath of the delivery system is smaller than the diameter of the stent, when storing the stent in the outer sheath, the stent is compressed and stored in the outer sheath. However, a stent having self-expanding force generates a repulsive force that tries to return to its original diameter while being diameter-reduced, so it is difficult to perform the operation of storing the stent in the outer sheath while compressing the stent.

[0005] On the other hand, when storing a stent in an outer sheath, a technique has been proposed to facilitate the storage of the stent in the outer sheath by reducing the diameter of the stent using a funnel-shaped stent storage jig (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] When storing a stent in a stent delivery system using a stent storage jig, it is further desired to easily store the stent in the stent delivery system.

[0008] An object of the present invention is to provide a stent storage jig capable of easily storing a stent in a stent delivery system and a stent delivery system including the same.

Means for Solving the Problems

[0009] The present invention relates to a stent storage jig used for a stent delivery system for implanting a stent into a living body. The stent delivery system includes an outer cylinder capable of storing the stent in a reduced diameter state inside the tip side, an inner member disposed inside the outer cylinder so as to be able to advance and retreat in the axial direction, and a tip of the inner member protruding outside the tip side in the axial direction of the outer cylinder. The stent storage jig includes a core member formed in a cylindrical shape, having a storage portion on the outside where the stent is disposed and capable of storing the tip chip inside, a guide member disposed between the core member and the outer cylinder in the axial direction of the outer cylinder, formed in a cylindrical shape having a tapered inner surface that tapers as it goes from the core member side to the outer cylinder side, with the portion on the outer cylinder side connected to the outer cylinder and the surface on the core member side disposed away from the core member, and a connecting member disposed outside the core member for connecting the core member and the guide member in a state where their axial directions coincide with each other.

[0010] Further, it is preferable that the core member has a tapered outer surface that tapers as it goes toward the guide member side at the end on the guide member side.

[0011] Further, it is preferable to further include a fixing member for fixing the position of the tip chip with respect to the outer cylinder.

[0012] Further, the guide member has an inner peripheral surface of a mounting portion provided at the end on the outer cylinder side and having an inner diameter substantially the same as the outer diameter of the outer cylinder, an outer cylinder mounting portion into which the end on the tip side of the outer cylinder is inserted, and an adjacent inner peripheral surface disposed adjacent to the tip side of the inner peripheral surface of the mounting portion and having a smaller diameter than the inner peripheral surface of the mounting portion. It is preferable that a step difference equal to or greater than the thickness of the outer cylinder is formed between the inner peripheral surface of the mounting portion and the adjacent inner peripheral surface.

[0013] The present invention relates to a stent delivery system including the stent storage jig, the outer cylinder, the inner member provided with the tip chip, and a string member inserted into the inner part of the outer cylinder, wherein one end side is connected to the stent outside the tip side in the axial direction of the outer cylinder and the other end side is passed through a hole formed in the base end side in the axial direction of the outer cylinder. The stent is disposed on the outer periphery of the core member, and the tip chip is stored in the storage portion.

Advantages of the Invention

[0014] According to the present invention, it is possible to provide a stent storage jig capable of easily storing a stent in a stent delivery system and a stent delivery system including the same.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Figure 6A

Figure 6B

Figure 6C

Embodiments for Carrying Out the Invention

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, the proximal end side of the stent delivery system 1 is taken as the proximal end side and is shown as the Y direction in the drawings. Also, the side opposite to the proximal end side of the stent delivery system 1 is taken as the distal end side and is shown as the X direction in the drawings.

[0017] The stent storage jig 60 according to the present invention is used in a stent delivery system 1 for implanting the stent 10 into a living body. In the present embodiment, the stent delivery system 1 includes the stent storage jig 60 and is shipped to the market and distributed in the state shown in FIG. 1 in which the stent 10 is stored in the stent storage jig 60.

[0018] As shown in FIG. 1, the stent delivery system 1 includes a stent 10, an outer cylinder 20, a guide wire induction tube 30 (internal member), a tip chip 40, an intermediate cylinder 50, a stent storage jig 60, a clip member 71 (fixing member), and a mandrel member 72.

[0019] The stent 10 is formed in a mesh-like cylindrical shape. In the present embodiment, as the stent 10, a resin stent having a self-expanding function is used. Since the resin stent has a weak self-expanding function, it is circulated in a state of being stored inside the stent storage jig 60 without reducing the diameter of the stent 10, and immediately before use, the stent 10 is reduced in diameter and stored in the outer cylinder 20. As the material of the resin stent, for example, polydioxanone or the like is preferably used. Although a resin stent is preferably used as the stent, it is not limited to the resin stent, and a metal stent may be used.

[0020] The outer cylinder 20 can store the stent 10 in a state where its diameter is reduced inside the tip side (X direction side). The inner diameter of the outer cylinder 20 only needs to be formed to a diameter that can store the stent 10 in a reduced diameter state in the radial direction. For example, when the stent 10 is applied to a small intestine stent, the inner diameter of the outer cylinder 20 is preferably 2.8 mm to 3.2 mm. Further, for example, when the stent 10 is applied to an esophageal stent, the inner diameter of the outer cylinder 20 is preferably 4.6 mm to 9.0 mm. The outer cylinder 20 is formed of, for example, nylon with a metal blade woven therein, and as an example, PTFE (polytetrafluoroethylene) is used for the innermost layer in contact with the stent 10 in order to improve slidability.

[0021] The guide wire conduit 30 extends in the axial direction of the outer cylinder 20 and is disposed inside the outer cylinder 20 so as to be able to advance and retreat in the axial direction of the outer cylinder 20. The guide wire conduit 30 can be disposed in a state where its tip protrudes outside the tip side (X direction side) in the axial direction of the outer cylinder 20.

[0022] The guide wire conduit 30 only needs to be disposed inside the outer cylinder 20 so as to be able to advance and retreat, and any material and inner and outer diameters can be appropriately used. In the present embodiment, as an example, a guide wire conduit 30 having an outer diameter of 1.1 mm, an inner diameter of 1.0 mm, and a material of PEEK (polyetheretherketone) resin is used. Further, a tip chip 40 described later is connected to the tip of the guide wire conduit 30.

[0023] The guide wire guiding tube 30 is formed with a through hole through which a guide wire (not shown) can be inserted from the tip to the base end. Although not shown in the drawing, the guide wire guides the insertion of the stent delivery system 1 into the body when the stent 10 is implanted in the body. When implanting the stent 10 in the body, after the guide wire reaches the site where the stent 10 is to be implanted, the stent delivery system 1 is advanced into the body along the guide wire, so that the stent 10 can be carried to the target site.

[0024] In the stent delivery system 1 in which the stent 10 is stored by the stent storage jig 60 in the through hole of the guide wire guiding tube 30, a mandrel member 72 is inserted from the tip side of the tip chip 40 (described later) across the through hole of the tip chip 40 and the through hole of the guide wire guiding tube 30 so as to reinforce the strength of the guide wire guiding tube 30 and the tip chip 40 described later. The mandrel member 72 has a bent portion that catches on the tip of the tip chip 40 and is formed to extend axially from the bent portion by a predetermined length. The mandrel member 72 is inserted from the tip of the tip chip 40 to the middle of the guide wire guiding tube 30.

[0025] When the stent 10 is implanted in the body, the mandrel member 72 is removed from the through hole of the guide wire guiding tube 30. After removing the mandrel member 72 from the through hole of the guide wire guiding tube 30, when the stent 10 is implanted in the body, a guide wire (not shown) is inserted into the through hole of the guide wire guiding tube 30.

[0026] As shown in FIG. 2, the tip chip 40 is connected to the tip of the guide wire guiding tube 30. In the stent delivery system 1 in which the stent 10 is stored by the stent storage jig 60, the tip chip 40 is stored in a storage portion 618 formed on the base end side (Y-direction side) of the core member 614 of the core member configuration portion 61 described later.

[0027] The tip chip 40 is connected to the tip of the guide wire conduit 30. With the guide wire conduit 30 protruding outside the axial tip side (X-direction side) of the outer cylinder 20, it is arranged at a predetermined distance L from the tip of the outer cylinder 20 to the tip side (X-direction side) along the axial direction of the guide wire conduit 30. Only the guide wire conduit 30 is arranged between the base end of the tip chip 40 and the tip of the outer cylinder 20. The space between the base end of the tip chip 40 and the tip of the outer cylinder 20 serves as a gap through which the stent 10 can pass when the stent 10 is moved from the stent storage jig 60 side to the outer cylinder 20 side.

[0028] In this embodiment, the position of the tip chip 40 relative to the outer cylinder 20 is fixed by the clip member 71. Specifically, as shown in FIG. 1, on the base end side (Y-direction side) in the axial direction of the outer cylinder 20, the clip member 71 sandwiches and fixes the intermediate cylinder 50, which is fixed outside the outer cylinder 20 and the guide wire conduit 30, so as to maintain a gap of a predetermined distance L formed between the tip chip 40 and the outer cylinder 20.

[0029] As shown in FIG. 2, the tip chip 40 has a base end side portion 41 and a tip end side portion 42. The base end side portion 41 is arranged on the base end side (Y-direction side) of the tip chip 40 and is formed in a tapered shape with an outer diameter that increases from the base end to the tip. The tip end side portion 42 is arranged on the tip end side (X-direction side) of the tip chip 40 and is formed in a tapered shape with an outer diameter that decreases from the base end to the tip.

[0030] As shown in FIG. 2, the maximum outer diameter R1 of the tip chip 40 is formed to be smaller than the diameter of the opening 617 of the core member 614 of the core member configuration portion 61, which will be described later, and also smaller than the inner diameter of the outer cylinder 20. A through hole (not shown) penetrating in the axial direction is formed in the tip chip 40. A guide wire (not shown) can be inserted through the through hole of the tip chip 40.

[0031] In the stent delivery system 1 in which the stent 10 is stored by the stent storage jig 60 in the through hole of the tip chip 40, as described above, the core member 72 is inserted across the through hole of the tip chip 40 and the through hole of the guide wire conduit 30 so as to reinforce the strength of the tip chip 40 and the guide wire conduit 30.

[0032] As the material constituting the tip chip 40, an elastic member having biocompatibility and flexibility is used. Specifically, thermoplastic elastomers such as polyurethane-based elastomers, polyamide-based elastomers, and polystyrene-based elastomers are preferably used.

[0033] As shown in FIG. 1, the intermediate cylinder 50 is disposed outside the guide wire conduit 30 inside the outer cylinder 20. The intermediate cylinder 50 is formed in a cylindrical shape having an outer diameter corresponding to the inner diameter of the outer cylinder 20 and extends in the axial direction of the outer cylinder 20. Inside the intermediate cylinder 50, a guide wire conduit 30 extending in the axial direction is inserted and disposed. The intermediate cylinder 50 is fixed to the guide wire conduit 30 with an adhesive and is movable in the axial direction of the outer cylinder 20 in conjunction with the guide wire conduit 30.

[0034] When the stent 10 is to be placed in the living body in a state where the stent 10 is stored inside the outer cylinder 20, the intermediate cylinder 50 moves the guide wire conduit 30 to the tip side (X direction side) with respect to the outer cylinder 20, and thus moves in conjunction with the guide wire conduit 30. Thereby, the intermediate cylinder 50 can push out the stent 10 from the inside of the outer cylinder 20 to the outside by moving the guide wire conduit 30 in the axial direction.

[0035] As shown in FIGS. 3 and 4, the stent storage jig 60 includes a core member configuration part 61, a guide member 62, and a connecting outer cylinder member 63 (connecting member).

[0036] The core member forming portion 61 has a tip fixing cylinder portion 611 and a core member 614. The tip fixing cylinder portion 611 is formed in a cylindrical shape and is disposed on the tip side (X direction side) of the stent delivery system 1. The tip fixing cylinder portion 611 has an annular portion 612 and a fixing cylinder portion 613 that projects cylindrically from the outer peripheral edge on the radially outer side of the annular portion 612 toward the base end side (Y direction side). On the inner peripheral surface of the fixing cylinder portion 613, a core member side connection screw portion 613a that is screwed and connected to the tip side connection screw portion 632 of the connecting outer cylinder member 63 is formed.

[0037] The core member 614 is formed in a cylindrical shape. The core member 614 has a shaft cylinder portion 615 that extends linearly along the axial direction from the inner peripheral edge on the radially inner side of the annular portion 612 of the tip fixing cylinder portion 611 toward the base end side (Y direction side), and a tapered cylinder portion 616 that is connected to the base end side (Y direction side) of the shaft cylinder portion 615.

[0038] As shown in FIG. 1, a cylindrical stent 10 in an expanded state is disposed outside the shaft cylinder portion 615. A guide wire 11 (string member) is attached to the base end side (Y direction side) of the stent 10. As shown in FIG. 1, one end side of the guide wire 11 is connected to the stent 10 by being hooked in a ring shape on the base end side (Y direction side) of the stent 10, a middle portion thereof is passed through the inside of the outer cylinder connection cylinder portion 623 of a guide member 62 described later and the inside of the outer cylinder 20, and the other end side is passed through a side hole 20a formed on the base end side (Y direction side) of the outer cylinder 20.

[0039] As shown in FIG. 2, in a state where the guide member 62 is attached to the core member forming portion 61, the end portion on the base end side (Y direction side) of the tapered cylinder portion 616 is disposed with a gap of a predetermined distance S from the end portion on the tip side (X direction side) of the outer cylinder side inner peripheral surface 623a of the guide member 62 described later.

[0040] As shown in FIG. 2, the tapered cylindrical portion 616 is formed in a tapered shape whose diameter decreases from the distal end side to the proximal end side (Y-direction side) of the stent delivery system 1. The tapered cylindrical portion 616 has a tapered outer surface 616a. The tapered outer surface 616a is a tapered outer surface that decreases in diameter toward the guide member 62 side on the outer surface of the end portion of the core member 614 on the guide member 62 side.

[0041] An opening 617 into which the tip tip 40 can be inserted is formed at the proximal end side (Y-direction side) end of the tapered cylindrical portion 616. The inside of the tapered cylindrical portion 616 communicating with the opening 617 of the tapered cylindrical portion 616 constitutes a storage portion 618 capable of storing the tip tip 40 inserted from the opening 617. The storage portion 618 can store the tip tip 40 through the opening 617 of the tapered cylindrical portion 616.

[0042] The guide member 62 is formed in a cylindrical shape having a funnel-shaped portion. The guide member 62 is disposed between the outer cylinder 20 and the core member 614 in the axial direction of the guide wire conduit 30. An outer cylinder connection cylinder portion 623 (described later) of the guide member 62 on the outer cylinder 20 side is connected to the outer cylinder 20, and a tapered inner peripheral surface 622a (described later) of the funnel-shaped cylinder portion 622 of the guide member 62 on the core member 614 side is disposed away from the core member 614.

[0043] As shown in FIGS. 2 to 4, the guide member 62 has a distal end side cylinder portion 621, a funnel-shaped cylinder portion 622, and an outer cylinder connection cylinder portion 623 (outer cylinder attachment portion). The distal end side cylinder portion 621, the funnel-shaped cylinder portion 622, and the outer cylinder connection cylinder portion 623 are continuously formed in this order from the distal end tip 40 side toward the outer cylinder 20 side in the axial direction.

[0044] As shown in FIG. 2, the distal end side cylinder portion 621 is formed in a cylindrical shape having the maximum diameter of the guide member 62 on the distal end side (X-direction side) of the guide member 62 and extends in the axial direction by a predetermined length. The funnel-shaped cylinder portion 622 extends from the proximal end side (Y-direction side) end of the distal end side cylinder portion 621 toward the proximal end side (Y-direction side). The funnel-shaped cylinder portion 622 is formed in a funnel shape whose diameter decreases from the distal end side (X-direction side) toward the proximal end side (Y-direction side).

[0045] The outer cylinder connection cylinder portion 623 is provided at the end portion on the outer cylinder 20 side of the guide member 62. The outer cylinder connection cylinder portion 623 is formed in a cylindrical shape with the smallest diameter in the guide member 62, and is formed in a cylindrical shape extending from the end portion on the base end side (Y direction side) of the funnel-shaped cylinder portion 622 toward the base end side (Y direction side). The end portion on the tip side (X direction side) of the outer cylinder 20 is connected to the outer cylinder connection cylinder portion 623.

[0046] As shown in FIG. 2, the inner peripheral surface of the guide member 62 is formed continuously with the tip chip side inner peripheral surface 621a, the tapered inner peripheral surface 622a (tapered inner surface), and the outer cylinder side inner peripheral surface 623a corresponding to the inner peripheral surfaces of the tip side cylinder portion 621, the funnel-shaped cylinder portion 622, and the outer cylinder connection cylinder portion 623, respectively.

[0047] The tip chip side inner peripheral surface 621a is the inner peripheral surface of the tip side cylinder portion 621, and extends in the axial direction with the largest diameter on the inner peripheral surface of the guide member 62. A tip chip side screw portion 621b is formed on the tip chip side inner peripheral surface 621a. The base end side connection screw portion 633 of the connecting outer cylinder member 63 described later is screwed and connected to the tip chip side screw portion 621b.

[0048] The tapered inner peripheral surface 622a is the inner peripheral surface of the funnel-shaped cylinder portion 622. The tapered inner peripheral surface 622a decreases in diameter from the core member 614 side toward the outer cylinder 20 side.

[0049] The outer cylinder side inner peripheral surface 623a is the inner peripheral surface of the outer cylinder connection cylinder portion 623. The outer cylinder side inner peripheral surface 623a has a minimum diameter inner peripheral surface 624 (adjacent inner peripheral surface) and a base end side inner peripheral surface 625 (attachment portion inner peripheral surface).

[0050] The minimum diameter inner peripheral surface 624 is formed on the X direction side of the outer cylinder side inner peripheral surface 623a, and is the inner peripheral surface with the minimum inner diameter R2 on the inner peripheral surface of the guide member 62. The minimum diameter inner peripheral surface 624 is disposed adjacent to the tip side of the base end side inner peripheral surface 625.

[0051] The proximal-end-side inner peripheral surface 625 is formed on the Y-direction side of the outer cylinder-side inner peripheral surface 623a. The proximal-end-side inner peripheral surface 625 is an inner peripheral surface having an inner diameter substantially the same as the outer diameter of the outer cylinder 20. The end portion on the distal-end side (X-direction side) of the outer cylinder 20 is inserted into the proximal-end-side inner peripheral surface 625. The proximal-end-side inner peripheral surface 625 is formed by an inner peripheral surface having a larger diameter than the minimum-diameter inner peripheral surface 624. In other words, the minimum inner diameter R2 of the minimum-diameter inner peripheral surface 624 is smaller than the inner diameter R3 of the proximal-end-side inner peripheral surface 625 (R2 < R3).

[0052] A step 626 having the same height as the thickness T of the outer cylinder 20 is formed between the proximal-end-side inner peripheral surface 625 and the minimum-diameter inner peripheral surface 624. The minimum-diameter inner peripheral surface 624 of the guide member 62 is disposed adjacent to the distal-end side of the proximal-end-side inner peripheral surface 625 of the guide member 62.

[0053] When a step 626 having the same height as the thickness T of the outer cylinder 20 is formed between the proximal-end-side inner peripheral surface 625 and the minimum-diameter inner peripheral surface 624, when the distal end of the outer cylinder 20 is attached to the outer cylinder connection cylinder portion 623, the inner peripheral surface of the outer cylinder 20 does not protrude radially inward from the minimum-diameter inner peripheral surface 624. Therefore, when the stent 10 is introduced into the outer cylinder 20 using the stent storage jig 60, no step is generated where the stent 10 gets caught when passing through the outer cylinder-side inner peripheral surface 623a of the stent storage jig 60. Thus, the stent 10 can be smoothly inserted into the guide member 62 and smoothly introduced into the outer cylinder 20.

[0054] In addition, in the present embodiment, a step 626 having the same height as the thickness T of the outer cylinder 20 is formed between the proximal-side inner peripheral surface 625 and the minimum-diameter inner peripheral surface 624, but the present invention is not limited thereto. A step 626 larger than the thickness T of the outer cylinder 20 may be formed between the proximal-side inner peripheral surface 625 and the minimum-diameter inner peripheral surface 624. As a result, when the tip of the outer cylinder 20 is attached to the outer cylinder connection cylinder portion 623, the inner peripheral surface of the outer cylinder 20 is recessed in the radial direction from the minimum-diameter inner peripheral surface 624 of the guide member 62 and does not protrude in the radial direction from the minimum-diameter inner peripheral surface 624. Therefore, when the stent 10 is introduced into the outer cylinder 20 using the stent storage jig 60, no step where the stent 10 gets caught occurs, and thus the stent 10 can be smoothly introduced into the outer cylinder 20 in the same manner as when a step 626 having the same thickness T as the outer cylinder 20 is formed between the proximal-side inner peripheral surface 625 and the minimum-diameter inner peripheral surface 624.

[0055] The connecting outer cylinder member 63 is disposed outside the core member 614 of the core member configuration portion 61 and is formed in a cylindrical shape extending in the axial direction. The connecting outer cylinder member 63 connects the core member 614 and the guide member 62 in a state where their central axes coincide with each other. The connecting outer cylinder member 63 is disposed so as to cover the stent 10 disposed on the outer periphery of the core member 614 of the core member configuration portion 61.

[0056] A plurality of slit-shaped openings 631 are formed in the connecting outer cylinder member 63. The plurality of slit-shaped openings 631 are formed in an oval shape extending in the axial direction. By forming the plurality of slit-shaped openings 631, the state of the stent 10 inside the connecting outer cylinder member 63 can be easily visually recognized. Also, by forming the plurality of slit-shaped openings 631, the cost required for the material of the connecting outer cylinder member 63 can be reduced. Note that the state of the stent 10 inside the connecting outer cylinder member 63 may be made easier to visually recognize by forming the connecting outer cylinder member 63 from a transparent or translucent resin material. In this case, the slit-shaped openings 631 may or may not be formed in the connecting outer cylinder member 63.

[0057] The connecting outer cylinder member 63 has a distal-end-side connection thread portion 632 formed on the outer peripheral surface on the distal-end side (X-direction side) and a proximal-end-side connection thread portion 633 formed on the outer peripheral surface on the proximal-end side (Y-direction side). The core-member-side connection thread portion 613a of the tip fixing cylinder portion 611 of the core member component 61 is screwed and connected to the distal-end-side connection thread portion 632. The tip-chip-side thread portion 621b on the inner peripheral surface 621a on the tip-chip side of the tip-side cylinder portion 621 of the guide member 62 is screwed and connected to the proximal-end-side connection thread portion 633.

[0058] Next, with reference to FIGS. 5A to 5D, a method for assembling the stent delivery system 1 using the stent storage jig 60 will be described. In the present embodiment, for example, a resin stent is used as the stent 10 to be stored in the stent delivery system 1.

[0059] First, as shown in FIG. 5A, the guide member 62 of the stent storage jig 60 is connected to the tip of the outer cylinder 20. Then, one end of the guide wire 11 is annularly attached to the end side on the proximal-end side (Y-direction side) of the stent 10, the guide wire 11 is passed through the inside of the outer cylinder 20, and the other end of the guide wire 11 is pulled out from the side hole 20a formed on the proximal-end side (Y-direction side) of the outer cylinder 20.

[0060] Next, as shown in FIG. 5B, with the connecting outer cylinder member 63 attached to the core member component 61, a tubular stent 10 in an expanded state is inserted between the core member 614 of the core member component 61 and the connecting outer cylinder member 63. As a result, the stent 10 is disposed on the outer periphery of the core member 614 of the core member component 61, and the outside is covered by the connecting outer cylinder member 63.

[0061] Subsequently, as shown in FIG. 5C, the tip chip 40 is inserted into the inside of the core member 614 through the opening 617 at the tip on the proximal-end side of the core member 614 of the core member component 61, so that the tip chip 40 is stored in the storage portion 618 as shown in FIG. 2. Then, from the state shown in FIG. 5C, the guide member 62 is connected to the connecting outer cylinder member 63. As a result, as shown in FIG. 5D, the stent delivery system 1 can be assembled. In this state, the stent delivery system 1 is sterilized and shipped to the market.

[0062] Next, with reference to FIGS. 6A to 6C, a method of using the stent delivery system 1 will be described. A method of storing the stent 10 inside the outer cylinder 20 and implanting the stent 10 at a stenosis in a living body using the stent delivery system 1 will be described.

[0063] From the state shown in FIG. 5D, by pulling the guide wire 11 passed through the side hole 20a of the outer cylinder 20, as shown in FIG. 6A, with the tip 40 housed in the housing portion 618 of the core member 614 of the core member configuration portion 61, the stent 10 connected to the tip side of the guide wire 11 is pulled into the outer cylinder 20.

[0064] Here, in the stent delivery system 1, the core member 614 has a tapered outer surface 616a, and the guide member 62 has a tapered inner peripheral surface 622a. The end on the proximal side (Y-direction side) of the tapered cylinder portion 616 of the core member 614 is disposed at a position with a gap of a predetermined distance S from the end on the distal side (X-direction side) of the outer cylinder side inner peripheral surface 623a of the outer cylinder connection cylinder portion 623 of the guide member 62.

[0065] Therefore, when moving the stent 10 to the outer cylinder 20 side, the stent 10 can be smoothly moved along the guide wire induction tube 30 through a gap of a predetermined distance S between the end on the distal side (X-direction side) of the outer cylinder side inner peripheral surface 623a of the outer cylinder connection cylinder portion 623 of the guide member 62 and the end on the proximal side (Y-direction side) of the tapered cylinder portion 616 of the core member 614. Then, the tapered cylinder portion 616 of the core member 614 and the tapered inner peripheral surface 622a of the guide member can smoothly guide the stent 10 to become smaller inward in the radial direction.

[0066] Further, the tip chip 40 is stored in the storage portion 618 of the core member 614 of the core member configuration portion 61. Therefore, when the stent 10 is moved, the stent 10 does not contact the tip chip 40. As a result, since the tip chip 40 is prevented from entering the mesh of the stent 10, the stent 10 is prevented from being caught by the tip chip 40, and the stent 10 is prevented from being deformed.

[0067] Further, by forming a step 626 that is the same as the thickness T of the outer cylinder 20 between the proximal end side inner peripheral surface 625 and the minimum diameter inner peripheral surface 624, when the tip of the outer cylinder 20 is attached to the outer cylinder connection cylinder portion 623, the inner peripheral surface of the outer cylinder 20 does not protrude radially inward from the minimum diameter inner peripheral surface 624. As a result, when the stent 10 is introduced into the outer cylinder 20 using the stent storage jig 60, no step is generated that catches the stent 10 when it passes through the outer cylinder side inner peripheral surface 623a of the stent storage jig 60. Therefore, the stent 10 can be smoothly inserted through the guide member 62. Thus, the stent 10 can be easily introduced into the interior of the outer cylinder 20.

[0068] From the state shown in FIG. 6A, by further pulling the guiding wire 11 passed through the side hole 20a of the outer cylinder 20, as shown in FIG. 6B, all of the stent 10 is stored inside the outer cylinder 20.

[0069] Then, as shown in FIG. 6B, the guiding wire 11 is cut outside the side hole 20a, and the stent storage jig 60 is moved to the tip side (X direction side). As shown in FIG. 6C, the stent storage jig 60 is removed from the tips of the outer cylinder 20, the tip chip 40, and the guide wire guiding tube 30. Also, the clip member 71 (see FIG. 1) and the mandrel member 72 are removed.

[0070] In this state, after a guide wire (not shown) passed through the through hole of the tip chip 40 and the through hole of the guide wire guiding tube 30 reaches the site where the stent 10 is to be placed, the tip chip 40, the guide wire guiding tube 30, and the outer cylinder 20 are advanced into the body to carry the tip chip 40, the guide wire guiding tube 30, and the outer cylinder 20 to the target site.

[0071] Then, at the site where the stent 10 is to be implanted, the guide wire conduit 30 is advanced into the body, so that the intermediate cylinder 50 that moves in conjunction with the guide wire conduit 30 is moved toward the distal end side (X-direction side), and the stent 10 is pushed out of the outer cylinder 20 by the intermediate cylinder 50. In this way, the stent 10 that is reduced in diameter and stored in the outer cylinder 20 can be expanded by being pushed out of the outer cylinder 20 and implanted in the stenotic part in the patient's body.

[0072] According to the stent storage jig 60 according to the present embodiment, the following effects can be obtained.

[0073] The stent storage jig 60 of the present embodiment is configured to be used in the stent delivery system 1. The stent delivery system 1 includes an outer cylinder 20 that can store the stent 10 in a reduced-diameter state inside the distal end side, an inner member 30 that is disposed inside the outer cylinder 20 so as to be able to advance and retreat in the axial direction and whose distal end is disposed in a state of protruding outside the axial distal end side of the outer cylinder 20, and a distal tip 40 provided at the distal end of the inner member 30. The stent storage jig 60 includes a core member 614 having a storage portion 618 where the stent 10 is disposed outside and the distal tip 40 is stored inside, a guide member 62 formed in a cylindrical shape having a tapered inner peripheral surface 622a that tapers as it goes from the core member 614 side to the outer cylinder 20 side and is disposed between the core member 614 and the outer cylinder 20, and a connecting outer cylinder member 63 that connects the core member 614 and the guide member 62 in a state where their axial directions coincide with each other. Thereby, the stent 10 can be easily stored in the stent delivery system 1.

[0074] In addition, conventionally, when the stent 10 is a resin stent, if the stent 10 is stored inside the outer cylinder 20 for a long time, the stent 10 may be deformed, and the expansion force when releasing the stent from the outer cylinder 20 may decrease. On the other hand, according to the present invention, immediately before the stent 10 is placed in the living body, the stent 10 can be reduced in diameter and stored inside the outer cylinder 20. Thereby, immediately before using the stent 10, the diameter of the stent 10 can be reduced and then expanded, so that it is possible to prevent the stent 10 from being deformed. Therefore, a decrease in the expansion force of the stent 10 can be suppressed.

[0075] Further, with the tip chip 40 stored in the storage portion 618 of the core member 614, the stent 10 can be drawn into the outer cylinder 20 and reduced in diameter. Therefore, when the stent 10 is drawn into the outer cylinder 20, the stent 10 does not contact the tip chip 40. Thereby, it is possible to prevent the tip chip 40 from entering and getting caught in the mesh of the stent 10, and it is possible to prevent the stent 10 from being deformed.

[0076] In addition, since the guide member 62 is formed in a cylindrical shape having a tapered inner peripheral surface 622a that decreases in diameter from the core member 614 side toward the outer cylinder 20 side, the stent 10 can be smoothly guided along the tapered inner peripheral surface 622a.

[0077] In the present embodiment, the core member 614 has a tapered outer surface 616a that decreases in diameter toward the guide member 62 side at the end on the guide member 62 side. Thereby, the stent 10 can be smoothly guided along the tapered outer surface 616a toward the guide member 62 side.

[0078] In the present embodiment, a clip member 71 for fixing the position of the tip chip 40 with respect to the outer cylinder 20 is provided. Thereby, when the stent 10 is drawn into the outer cylinder 20, a gap with a predetermined distance L formed between the tip chip 40 and the outer cylinder 20 can be maintained. Therefore, a gap with a predetermined distance L can be secured between the tip chip 40 and the outer cylinder 20, making it easier to pass the stent 10 through the gap.

[0079] In this embodiment, the inner peripheral surface 625 on the proximal end side of the guide member 62 has an outer cylinder connection cylinder portion 623 into which the end portion on the distal end side of the outer cylinder 20 is inserted, and a minimum diameter inner peripheral surface 624 that is disposed adjacent to the distal end side of the inner peripheral surface 625 on the proximal end side and has a smaller diameter than the inner peripheral surface 625 on the proximal end side. A step 626 equal to or greater than the thickness of the outer cylinder 20 is formed between the inner peripheral surface 625 on the proximal end side and the minimum diameter inner peripheral surface 624. Thereby, when the distal end of the outer cylinder 20 is attached to the outer cylinder connection cylinder portion 623, the inner peripheral surface of the outer cylinder 20 does not protrude radially inward of the minimum diameter inner peripheral surface 624. Therefore, when the stent 10 is introduced into the outer cylinder 20 using the stent storage jig 60, no step is generated that catches the stent 10 when passing through the outer cylinder side inner peripheral surface 623a of the stent storage jig 60, so that the stent 10 can be smoothly inserted through the guide member 62. Therefore, the stent 10 can be easily introduced into the stent delivery system 1.

[0080] In addition, the stent delivery system 1 includes a stent storage jig 60, an outer cylinder 20, a guide wire induction tube 30 provided with a tip chip 40, and a guiding thread 11 inserted into the outer cylinder 20. One end side is connected to the stent 10 outside the axial distal end side of the outer cylinder 20, and the other end side is passed through a hole formed in the axial proximal end side of the outer cylinder 20. The stent 10 is disposed on the outer periphery of the core member 614, and the tip chip 40 is stored in the storage portion 618. Thereby, the stent delivery system 1 can be configured more simply. Therefore, a stent delivery system 1 having a simple configuration can be sold on the market.

[0081] As described above, the preferred embodiments of the stent storage jig 60 of the present invention and the stent delivery system 1 including the same have been described. However, the present invention is not limited to the above-described embodiments and can be appropriately changed.

Description of reference numerals

[0082] 1 Stent delivery system 10 Stent 11 Guiding thread (string member) 20 Outer cylinder 30 guide wire catheter (inner member) 40 tip 60 stent storage jig 62 guide member 63 connecting outer cylinder member (connecting member) 618 storage part 614 core member 616a tapered outer surface 622a tapered inner peripheral surface (tapered inner surface) 623 outer cylinder connection cylinder part (outer cylinder attachment part) 624 minimum diameter inner peripheral surface (adjacent inner peripheral surface) 625 proximal end side inner peripheral surface (attachment part inner peripheral surface) 626 step

Claims

1. A stent storage jig used for a stent delivery system for implanting a stent into a living body, wherein the stent delivery system includes an outer cylinder capable of storing the stent in a reduced diameter state inside the tip side, an inner member disposed inside the outer cylinder so as to be movable forward and backward in the axial direction, and having a tip protruding outside the tip side in the axial direction of the outer cylinder, and a tip chip provided at the tip of the inner member, wherein the stent storage jig includes a core member formed in a cylindrical shape, having a storage portion on the outside where the stent is disposed and capable of storing the tip chip inside, a guide member disposed between the core member and the outer cylinder in the axial direction of the outer cylinder, formed in a cylindrical shape having a tapered inner surface that tapers as it goes from the core member side to the outer cylinder side, with the portion on the outer cylinder side connected to the outer cylinder and the surface on the core member side disposed away from the core member, and a connecting member disposed outside the core member for connecting the core member and the guide member in a state where their axial directions coincide with each other. The stent storage jig is provided.

2. The stent storage jig according to claim 1, wherein the core member has a tapered outer surface that tapers as it goes toward the guide member side at the end on the guide member side.

3. The stent storage jig according to claim 1 or 2, further comprising a fixing member for fixing the position of the tip chip with respect to the outer cylinder.

4. The guide member has an inner peripheral surface of a mounting portion provided at the end on the outer cylinder side and having an inner diameter substantially the same as the outer diameter of the outer cylinder, and an outer cylinder mounting portion into which the end on the tip side of the outer cylinder is inserted, and an adjacent inner peripheral surface disposed adjacent to the tip side of the inner peripheral surface of the mounting portion and having a smaller diameter than the inner peripheral surface of the mounting portion, wherein a step difference equal to or greater than the thickness of the outer cylinder is formed between the inner peripheral surface of the mounting portion and the adjacent inner peripheral surface. The stent storage jig according to any one of claims 1 to 3.

5. A stent delivery system comprising the stent storage jig according to any one of claims 1 to 4, the outer cylinder, the inner member provided with the tip chip, and a string member inserted into the outer cylinder, one end of which is connected to the stent outside the tip side in the axial direction of the outer cylinder and the other end of which is passed through a hole formed on the base end side in the axial direction of the outer cylinder, wherein the stent is disposed on the outer periphery of the core member and the tip chip is stored in the storage portion.

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