JP2022124574A - Stent delivery apparatus - Google Patents

Abstract

To provide a stent delivery apparatus having a structure that can further reduce invasiveness at the time when inserted into a body cavity.SOLUTION: A stent delivery apparatus 100 includes an outer tube part 10, an outer tube handle 20, an inner tube part 40, an inner shaft 50 and a shaft handle 60. The outer tube part 10 has a base end side portion 18 and a tip side portion 17. The base end side portion 18 is made by using a first resin material as a base material. The tip side portion 17 is made by using a second resin material having the hardness being lower than that of the first resin material as the base material. In the circumferential direction of a boundary 12 between the tip side portion 17 and the base end side portion 18, a protruding portion 12a and a recessed portion 12b are present. In the axial direction of the outer tube part 10, a difference dimension between a maximum protruding place of the protruding portion 12a and a maximum recessed place of the recessed portion 12b is smaller than the dimension for one opening of a mesh 16a of a reinforcing layer 16.SELECTED DRAWING: Figure 7

Description

The present invention relates to stent delivery devices.

A stent delivery device used for indwelling a stent in a body cavity is disclosed, for example, in Patent Document 1. The stent delivery device of Patent Document 1 (described as an indwelling device delivery device in the same document) includes a tubular body that holds a stent (described as an indwelling device in the same document) to be indwelled in a body cavity, and a distal portion of the tubular body. and a restricting member capable of restricting movement of the stent to the proximal side. The stent can be deployed in the body lumen by moving it relative to the member.

JP 2020-078459 A

According to the studies of the inventors of the present application, the stent delivery device of Cited Document 1 still has room for improvement from the viewpoint of reducing the invasiveness when it is inserted into a body cavity.

The present invention has been made in view of the above problems, and provides a stent delivery device having a structure that can further reduce invasiveness when it is inserted into a body cavity.

According to the present invention, the outer tube portion;
an outer tube handle to which a proximal end portion of the outer tube portion is fixed;
an inner tube portion axially slidably inserted through the outer tube portion;
an inner shaft integrated with the inner tube portion and extending proximally from the outer tube handle;
a shaft handle to which the proximal end of the inner shaft is fixed;
with
By retracting the outer tube handle together with the outer tube toward the shaft handle, the distal end of the inner tube is exposed from the outer tube, and the stent held by the inner tube is left in the body cavity. is possible and
The outer tube portion has a proximal side portion and a distal side portion connected to the distal side of the proximal side portion,
The base end portion is configured using a first resin material as a base material,
The tip side portion is configured using a second resin material having a hardness lower than that of the first resin material as a base material,
a protruding portion in which a boundary line between the distal side portion and the proximal side portion protrudes toward the distal side in the circumferential direction of the boundary portion between the distal side portion and the proximal side portion; There is a recessed part that is convex on the proximal side,
The outer tube portion includes a reinforcing layer formed in a mesh shape by braided metal wires,
a series of reinforcing layers extending from the proximal portion to the distal portion;
Regarding the protruding portion and the recessed portion adjacent to each other in the circumferential direction of the boundary,
In the axial direction of the outer tube portion, the differential dimension between the maximum projecting portion of the projecting portion and the maximum recessed portion of the recessed portion is smaller than the dimension of one mesh opening of the reinforcing layer. An apparatus is provided.

According to the present invention, it is possible to further reduce invasiveness when a stent delivery device is inserted into a body cavity.

1 is a schematic overall view of a stent delivery device according to an embodiment; FIG. FIG. 2 is a cross-sectional view taken along line AA shown in FIG. 1; FIG. 2 is a cross-sectional view taken along line BB shown in FIG. 1; FIG. 3 is a cross-sectional view taken along line AA shown in FIG. 2; Fig. 4 is a side view showing the internal structure of the outer tube handle according to the embodiment; Fig. 6(a) is a cross-sectional view along the axis of the switching operation portion according to the embodiment, and Fig. 6(b) is a front view showing the threaded member according to the embodiment. FIG. 7(a) is a partially enlarged view of the portion C shown in FIG. 1, and FIG. 7(b) is a sectional view of FIG. 7(a). 1 is a schematic diagram showing a state in which a stent delivery device according to an embodiment is inserted into an endoscope; FIG. 9(a), 9(b), and 9(c) are diagrams for explaining the operation of the stent delivery device according to the embodiment, of which FIG. is slightly exposed from the outer tube portion, and FIG. 9(b) shows a state in which the tip of the inner tube portion is further exposed from the outer tube portion than in the state shown in FIG. 9(a). 9(c) shows a state in which the entire stent arrangement section in the inner tube is exposed from the outer tube. 10(a), 10(b), and 10(c) are diagrams for explaining the operation of the stent delivery device according to the embodiment, of which FIG. 10(a) is FIG. 10(b) shows the position of the outer tube handle in a state corresponding to FIG. 9(b), and FIG. 10(c) shows the position of the outer tube handle in a state corresponding to FIG. 9(c). ) shows the position of the outer tube handle in the corresponding state.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 10(c). In addition, in all the drawings, the same reference numerals are given to the same constituent elements, and the description thereof will be omitted as appropriate. 1, 2, 3, 4 and 9(a), the stent 200 is indicated by a chain double-dashed line. Also, in FIG. 6B, illustration of the inner shaft 50 and the ring member 33 is omitted. 7(b) is a cross-sectional view taken along line AA shown in FIG.
It should be noted that the various components of the stent delivery device 100 of the present invention do not need to exist individually. that a plurality of constituent elements are formed as one member, that one constituent element is formed of a plurality of members, that a certain constituent element is part of another constituent element, or that a certain constituent element is one It is permissible for a part and a part of another component to overlap, and so on.
Further, hereinafter, the distal side of the stent delivery device 100 is also referred to as the distal side, and the proximal side thereof is referred to as the proximal side. In addition, the distal end means a certain range including the distal end (most proximal end) and its periphery, and the proximal end means a certain range including the proximal end (most proximal end) and its periphery. shall be

As shown in FIG. 1, a stent delivery device 100 according to this embodiment includes an outer tube portion 10, an outer tube handle 20 to which a proximal end portion 10a of the outer tube portion 10 is fixed, and a an inner tube portion 40 axially slidably inserted through the inner tube portion 40; an inner shaft 50 integrated with the inner tube portion 40 and extending proximally from the outer tube handle 20; and a shaft handle 60 to which the proximal end of the shaft handle 60 is fixed.
By retracting the outer tube handle 20 together with the outer tube portion 10 toward the shaft handle 60, the distal end portion 40b of the inner tube portion 40 is exposed from the outer tube portion 10, and the stent 200 held by the inner tube portion 40 is moved into the body cavity. can be placed in
The outer tube portion 10 has a proximal side portion 18 and a distal side portion 17 connected to the distal side of the proximal side portion 18. The proximal side portion 18 is made of a first resin material as a base material. , and the distal end portion 17 is configured using a second resin material having a hardness lower than that of the first resin material as a base material.
As shown in FIG. 7A, in the circumferential direction of the boundary 12 between the distal side portion 17 and the proximal side portion 18, the boundary line between the distal side portion 17 and the proximal side portion 18 is convex to the distal side. There are a protruding portion 12a that is formed and a recessed cutout portion 12b that has a boundary line that protrudes toward the base end.
As shown in FIG. 7(b), the outer tube portion 10 includes a reinforcing layer 16 made up of braided metal wires in a mesh pattern, and a series of reinforcing layers 16 extends from a proximal portion 18 to a distal portion. 17 are located.
Regarding the protruding portion 12a and recessed portion 12b that are adjacent to each other in the circumferential direction of the boundary, the difference dimension between the maximum protruding portion of the protruding portion 12a and the maximum recessed portion of the recessed portion 12b in the axial direction of the outer tube portion 10 ( L1) shown in FIG. 7A) is smaller than the size of one opening of the mesh 16a of the reinforcing layer 16 (L2 shown in FIG. 7A).
The dimension L2 for one opening of the mesh 16a means the opening width of the mesh 16a in the axial direction.

According to the present embodiment, the distal end portion 17 is made of the second resin material having a hardness lower than that of the first resin material as a base material. That is, since the distal end portion 17 is softer than the proximal end portion 18 (the bending rigidity of the distal end portion 17 is lower than the bending rigidity of the proximal end portion 18), the stent delivery device 100 is inserted into the body cavity. When doing so, it is possible to easily realize a structure that allows the tip side portion 17 to well follow the curved shape of the body cavity.
Furthermore, according to the present embodiment, the boundary 12 between the distal end portion 17 and the proximal end portion 18 has a projecting portion 12a and a recessed portion 12b in the circumferential direction. As a result, in the boundary portion 12, a portion (distal side portion 17) having a lower hardness than other portions and a portion (base end side portion 18) having a higher hardness than the other portions are smoothly switched. Therefore, in this range, the kink of the outer tube portion 10 can be suppressed.
Thus, according to this embodiment, the invasiveness of the stent delivery device 100 when it is inserted into a body cavity can be further reduced.
Further, according to the present embodiment, in the axial direction of the outer tube portion 10, the difference L1 between the maximum protruding portion of the projecting portion 12a and the maximum recessed portion of the recessed portion 12b is equal to the mesh 16a of the reinforcing layer 16. It is smaller than the dimension L2 for one opening. Therefore, the appearance of the boundary portion 12 between the distal portion 17 and the proximal portion 18 is improved.
Further, according to this embodiment, since a series of reinforcing layers 16 are arranged from the proximal side portion 18 to the distal side portion 17, the connection strength between the distal side portion 17 and the proximal side portion 18 can be increased. can be secured.

When the stent 200 is held by the inner tube portion 40 , the stent 200 is accommodated between the inner peripheral surface of the outer tube portion 10 and the outer peripheral surface of the inner tube portion 40 in a reduced diameter state. Then, while the outer tube part 10 and the inner tube part 40 are inserted into the desired site of the body cavity along the guide wire 300 (see FIG. 10( a ), etc.), the outer tube handle 20 is moved together with the outer tube part 10 to the shaft handle. By retracting to the 60 side and exposing the distal end portion 40b of the inner tube portion 40 from the outer tube portion 10, the stent 200 can be deformed from the diameter-reduced state to the expanded state and left at the desired site. . More specifically, as the distal end portion 40b of the inner tube portion 40 is exposed from the outer tube portion 10, the stent 200 is also exposed from the outer tube portion 10, and the exposed portion of the stent 200 is deployed. That is, deployment of the stent 200 progresses according to the retraction amount of the outer tube handle 20 .
The contracted state of the stent 200 means a state in which the stent 200 is radially compressed, and the expanded state of the stent 200 means a state in which the stent 200 is radially expanded. .

The outer tube portion 10 is an elongated hollow tubular member. As shown in FIGS. 2 and 3, the inner tube portion 40 is inserted through the lumen of the outer tube portion 10, and the outer tube portion 10 is slidable relative to the inner tube portion 40 in its axial direction. .
In this embodiment, the inner and outer diameters of the outer tube portion 10 are constant regardless of the position in the axial direction, and therefore the thickness of the outer tube portion 10 is constant regardless of the position in the axial direction. However, the outer diameter and inner diameter of the outer tube portion 10 may differ depending on the position in the axial direction.
As shown in FIGS. 2 and 4, the outer tube portion 10 has, for example, a two-layer structure including an inner layer 14 and an outer layer 15 provided around the inner layer 14. , an inner layer 14 and an outer layer 15 are laminated in this order. Further, the reinforcing layer 16 is, for example, embedded in the outer layer 15 and arranged around the inner layer 14 .
A hydrophilic layer (not shown) may be formed on the surface of the outer layer 15 . The material of the hydrophilic layer is not particularly limited, but examples thereof include hydrophilic resin materials such as maleic anhydride-based polymers such as polyvinyl alcohol (PVA), copolymers thereof, and polyvinylpyrrolidone. By doing so, it is possible to reduce the sliding resistance when the outer tubular portion 10 is inserted into the body cavity of the living body.

The inner layer 14 is the innermost layer of the outer tube portion 10, and is formed, for example, in the shape of a circular tube whose wall thickness is constant regardless of the position in the axial direction. The inner layer 14 is open at both the distal end and the proximal end of the outer tube portion 10 .
The inner layer 14 is made of, for example, a fluorine-based thermoplastic polymer resin. The fluorine-based thermoplastic polymer material can be, but is not limited to, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), perfluoroalkoxy fluororesin (PFA), and the like. By forming the inner layer 14 from such a fluoropolymer material, the sliding resistance when the inner tubular portion 40 slides in the lumen of the outer tubular portion 10 is reduced.

The outer layer 15 is the outermost layer of the outer tubular portion 10 . For example, most (majority) of the thickness of the outer tube portion 10 is occupied by the thickness of the outer layer 15 . The outer layer 15 is formed, for example, in the shape of a circular tube whose thickness is constant regardless of the position in the axial direction.

Here, in the case of this embodiment, as shown in FIG. At 15, the portion forming the distal portion 17 and the portion forming the proximal portion 18 are molded separately from each other and then integrated with each other.
More specifically, in the outer layer 15, the portion forming the distal end portion 17 is formed of, for example, a first resin material, and the portion forming the proximal end portion 18 is formed, for example, of a second resin material. It is made of resin material.

In the case of this embodiment, when creating the outer tube portion 10 , first, metal wires are woven into a mesh on the outer peripheral surface of the inner layer 14 to form the reinforcing layer 16 . Subsequently, the resin tube made of the second resin material is inserted onto the distal end portion of the inner layer 14, and the resin tube made of the first resin material is inserted onto the proximal end portion of the inner layer 14. to extrapolate. Then, while the proximal end of the distal end portion 17 and the distal end of the proximal end portion 18 are abutted against each other, they are heat-sealed using a heat-shrinkable tube (not shown). As a result, in the outer layer 15, the portion forming the distal end portion 17 and the portion forming the proximal end portion 18 are heat-sealed to each other without a step in the radial direction.

The first resin material includes, for example, one or more polymers. The polymers are for example polyether block copolyamide polymers (e.g. PEBAX®), copolyester elastomers (e.g. Arnitel® copolyester elastomers), thermosetting polymers, polyolefins (e.g. Marlex® polyethylene , Marlex® polypropylene), high density polyethylene (HDPE), low density polyethylene (LDPE), polyamides (eg Vestamid®), polyetheretherketone (PEEK), and silicones. This polymer also includes thermoplastic polymers such as, for example, polyamides (eg, nylon), thermoplastic polyester elastomers (eg, Hytrel®), and thermoplastic polyurethane elastomers (eg, Pellethane™).
The second resin material may contain, for example, the same type of polymer as the first resin material and/or may contain a different type of polymer.

Moreover, as shown in FIG. 7A, it is preferable that a plurality of protruding portions 12a and a plurality of recessed portions 12b are repeatedly present in the circumferential direction of the boundary portion 12. As shown in FIG.
By doing so, at a plurality of locations in the circumferential direction of the boundary portion 12, a portion (distal side portion 17) having a lower hardness than other portions and a portion (base end side portion 18) having a higher hardness than other portions. , the kink of the outer tube portion 10 can be more reliably suppressed in this range.
In addition, in the example shown in FIG. 7A, the boundary line between the distal end portion 17 and the proximal end portion 18 is indicated by an irregular wavy line. That is, the plurality of protruding portions 12a includes protruding portions 12a having different dimensions in the axial direction. Similarly, the plurality of recessed cutouts 12b include recessed cutouts 12b having different dimensions in the axial direction.
Note that, for example, the first resin material forming the proximal side portion 18 may exist in an island shape on the distal side of the boundary line between the distal side portion 17 and the proximal side portion 18 . Similarly, the second resin material forming the distal portion 17 may exist in an island shape on the proximal side of the boundary line.
Also, the boundary line between the distal end portion 17 and the proximal end portion 18 may be, for example, a regular wavy line.

The inner diameter of the outer tube portion 10 is set to be larger than the outer diameter (maximum diameter) of the inner tube portion 40 . Therefore, the inner tube portion 40 can be slidably inserted into the lumen of the outer tube portion 10 .
More specifically, although the inner diameter of the outer tube portion 10 is not particularly limited, it is preferably 1 mm or more and 7 mm or less. Although the outer diameter of the outer tube portion 10 is not particularly limited, it is preferably 1.5 mm or more and 8 mm or less. The total length of the outer tube portion 10 is not particularly limited, but is preferably 500 mm or more and 2500 mm or less.

As described above, the reinforcement layer 16 is, for example, embedded in the outer layer 15 and arranged around the inner layer 14 . 1 and 8 to 10(c), illustration of the reinforcing layer 16 is omitted.
The reinforcement layer 16 is formed, for example, by braiding metal wires in a mesh shape around the inner layer 14 . FIG. 7A shows, as an example, a reinforcing layer 16 in which meshes 16a are substantially rhombic in shape. In addition, the substantially rhombus here means that the first diagonal is longer than the second diagonal, and the first diagonal and the second diagonal are substantially orthogonal. Further, the approximate rhombus here includes not only the rhombus but also flat polygons such as a kite shape (a kite shape) and a flat hexagon and a flat octagon. Further, the substantially elliptical shape includes eccentric circles such as ovals in addition to elliptical shapes and elliptical shapes.
The reinforcing layer 16 is arranged, for example, from the distal end to the proximal end of the outer tube portion 10 . The outer tube portion 10 is entirely reinforced with a reinforcing layer 16 .
The reinforcing layer 16 may be made of, for example, a metal wire wound in a coil shape. Further, the reinforcing layer 16 may be arranged on a part of the outer tube portion 10 in the axial direction, for example.

In the case of this embodiment, it is also preferable that the differential dimension L1 is larger than the dimension of half the opening of the mesh 16a (half the dimension L2).
By doing so, the first resin material and the second resin material are more sufficiently bonded to each other, so that the structure in which the distal end portion 17 and the proximal end portion 18 are more strongly connected can be achieved. realizable.

Further, in the case of this embodiment, for example, an annular marker member 11 is embedded in the vicinity of the tip of the outer tube portion 10 .
The marker member 11 is made of, for example, an X-ray opaque material such as platinum or tungsten. By using the position of the marker member 11 as an index, the position of the distal end portion 10b of the outer tube portion 10 in the body cavity can be accurately recognized under X-ray (radiation) observation.
However, if the marker member 11 is not embedded in the outer tube portion 10, the outer layer 15 of the outer tube portion 10 may be mixed with an inorganic filler. Examples of inorganic fillers include contrast agents such as barium sulfate and bismuth subcarbonate. By mixing a contrast agent into the outer layer 15, the X-ray contrastability of the outer tubular portion 10 inside the body cavity can be improved.

As shown in FIG. 5, the outer tube handle 20 is, for example, a hollow member, and has, for example, a substantially rectangular parallelepiped shape elongated in one direction. The inner shaft 50 is slidably inserted into the inside of the outer tube handle 20, and by moving the outer tube handle 20 along the inner shaft 50 toward the shaft handle 60, the outer tube portion 10 can be moved. The base end portion 10a of the can also be retracted along the inner shaft 50 toward the shaft handle 60 side.
Regarding the description of the outer tube handle 20, the left side in FIG. 5 is referred to as the distal side, and the right side in FIG. 5 is referred to as the proximal side. Also, the direction toward the distal side and the proximal side is referred to as the distal-basal direction.
As shown in FIGS. 1 and 5, the outer tube handle 20 has, for example, a first member 22a and a second member 22b, and the first member 22a and the second member 22b are assembled together. The outer tube handle 20 is constructed by being 5, the illustration of the second member 22b is omitted, and these figures are side views in which the internal structure of the outer tube handle 20 can be seen.
The first member 22a and the second member 22b are formed to have the same dimensions and the same outer shape.
The proximal end of the outer tube portion 10 is introduced into the outer tube handle 20 , and the proximal end portion 10 a of the outer tube portion 10 is arranged along the longitudinal direction of the outer tube handle 20 .

More specifically, as shown in FIG. 5, in the case of this embodiment, a fixing ring member 19 is provided on the outer circumference of the base end portion 10a of the outer tube portion 10. As shown in FIG. The outer tube handle 20 has an accommodation recess 23 , and the fixing ring member 19 is accommodated in the accommodation recess 23 , thereby fixing the outer tube portion 10 to the outer tube handle 20 .
The fixing ring member 19 is, for example, an annular member and is made of an elastic material such as silicone rubber or elastomer.
The fixing ring member 19 is fixed to the outer tube portion 10 by being fitted onto the outer tube portion 10, for example.
In addition, as shown in FIG. 5, a housing recess 23 having a rectangular shape in a side view is formed by four wall portions erected from the inner surface of the first member 22a. The fixing ring member 19 is housed inside the housing recess 23 , and movement of the fixing ring member 19 in the distal-to-basal direction is restricted by the housing recess 23 .
Here, two notch-shaped portions 24c are formed in the accommodation recess 23. As shown in FIG. Each cutout portion 24 c has a semicircular shape when viewed in the tip-to-base direction, and its diameter is set to be slightly larger than the outer diameter of the outer tube portion 10 . In the outer tube portion 10, portions closer to the proximal side and the distal end than the fixing ring member 19 protrude to the outside of the housing recess 23 through the notch-shaped portions 24c.
In addition, for example, the accommodation recess 23 may be similarly formed on the inner surface of the second member 22b. In this case, a portion of the fixing ring member 19 is arranged inside the accommodation recess 23 of the first member 22a and the remaining portion of the fixing ring member 19 is arranged inside the accommodation recess 23 of the second member 22b. be.

The outer tube handle 20 is made of, for example, a hard resin material. Hard resin materials are not particularly limited, but examples thereof include polyolefins such as polyethylene and polypropylene, polyamides, polycarbonates, and polystyrene.

As shown in FIGS. 1, 2, and 3, the inner tube portion 40 includes, for example, a relatively small-diameter small-diameter portion 41 and a relatively large-diameter large-diameter portion 42, for example.
Each of the small diameter portion 41 and the large diameter portion 42 is an elongated hollow tubular member. The outer diameter of the small diameter portion 41 is set smaller than the inner diameter of the large diameter portion 42, and as shown in FIG. is inserted into the Further, the overall length of the small diameter portion 41 is set to be longer than the overall length of the large diameter portion 42 . Using the large-diameter portion 42 as a reference, the small-diameter portion 41 protrudes from the opening on the distal end side of the large-diameter portion 42 toward the distal end side, and protrudes from the opening on the proximal end side of the large-diameter portion 42 toward the proximal end side. ing.
Here, in the small-diameter portion 41, a portion closer to the distal end than the distal end of the large-diameter portion 42 constitutes an arrangement section 41a in which the stent 200 is arranged. The stent 200 is held by the narrow diameter portion 41 of the inner tube portion 40 in a state of being fitted over the arrangement section 41 a of the narrow diameter portion 41 .
A portion of the small-diameter portion 41 that is closer to the proximal end than the proximal end of the large-diameter portion 42 is inserted through the lumen of the inner shaft 50 . More specifically, the distal end portion of the inner shaft 50 is inserted into the proximal opening of the large diameter portion 42, and the lumen of the large diameter portion 42 and the lumen of the inner shaft 50 communicate with each other. ing. The small-diameter portion 41 extends through the lumen of the large-diameter portion 42 and the inner shaft 50 , and further reaches the inside of the shaft handle 60 .

More specifically, for example, an endoscope visual recognition marker 46 is provided at the distal end of the large-diameter portion 42 . Therefore, in the small-diameter portion 41, the portion closer to the distal end than the endoscope visual recognition marker 46 is the arrangement section 41a, and the entire stent 200 is externally fitted in the arrangement section 41a. That is, an endoscope visual recognition marker 46 is arranged on the proximal end side of the stent 200 . Therefore, the user can easily grasp the position of the stent 200 by using the position of the endoscope visual recognition marker 46 as an index based on the image captured by the endoscope.
More specifically, when using the stent delivery device 100, as shown in FIG. It will be exposed from the tip of the part.
Also, the tip of the endoscope visual recognition marker 46 is fixed to the small diameter portion 41 . More specifically, the tip of the endoscope visual recognition marker 46 and the portion corresponding to the tip on the outer peripheral surface of the small-diameter portion 41 are coated with an adhesive 42a in a circular pattern. Thereby, the small diameter portion 41 is fixed to the endoscope visual recognition marker 46 and by extension to the large diameter portion 42 .
The proximal end of the endoscope visual recognition marker 46 is connected to the distal end side of the large diameter portion 42, and the lumen of the endoscope visual recognition marker 46 and the lumen of the large diameter portion 42 communicate with each other. Therefore, the small diameter portion 41 is inserted through the lumen of the endoscope visual recognition marker 46 and the lumen of the large diameter portion 42 . The outer diameter of the endoscope visual recognition marker 46 is set to be approximately the same as the outer diameter of the large-diameter portion 42 .
The endoscope visual recognition marker 46 is composed of, for example, a resin tube that is a separate member from the large-diameter portion 42 , and is colored in a color different from that of the large-diameter portion 42 . In addition, in the case of the present embodiment, the proximal portion 18 is, for example, colored and opaque (opaque to visible light), while the distal portion 17 is, for example, transparent (transparent to visible light). transparent). Therefore, the user can visually recognize the endoscope visual recognition marker 46 through the outer tube portion 10 .
The endoscope visual recognition marker 46 may be formed, for example, by applying ink to the tip of the large-diameter portion 42, or may be made of an X-ray opaque material such as platinum or tungsten. may

A tip 43 (see FIGS. 1 and 4) is provided at the tip of the small-diameter portion 41 . The distal tip 43 is formed, for example, in a conical shape whose diameter gradually decreases toward the distal end side. The proximal end portion of the distal tip 43 is connected to the distal end portion of the narrow diameter portion 41, and the lumen of the distal tip 43 and the lumen of the narrow diameter portion 41 communicate with each other.
When inserting the stent delivery device 100 into the body cavity, the guide wire 300 (see FIG. 9A, etc.), which has been inserted into the body cavity in advance, is passed through the opening on the distal end side of the distal tip 43 into the inner tube portion 40. inserted into the cavity. Thereby, the outer tube part 10 and the inner tube part 40 can be inserted into the body cavity along the guidewire 300 . 9(a) to 10(c), the guide wire 300 is indicated by a one-dot chain line.
Moreover, in the case of this embodiment, the proximal end of the distal tip 43 and the distal end of the outer tube portion 10 face each other. As shown in FIG. 4, the outer diameter of the distal tip 43 is set to be approximately equal to or slightly larger than the outer diameter of the outer tube portion 10, and the inner diameter of the distal tip 43 is The dimension is set to be smaller than the inner diameter of the outer tube portion 10 .
Therefore, for example, when the outer tube handle 20 is moved forward together with the outer tube portion 10 toward the distal tip 43 , the distal end face of the outer tube portion 10 abuts against the proximal end face of the distal tip 43 . Since further advancement is restricted, further advancement of the outer tube handle 20 integrated with the outer tube portion 10 is also restricted. In the following description, the initial state of the stent delivery device 100 is the state in which the distal end surface of the outer tube portion 10 is in contact with the proximal end surface of the distal tip 43 (see FIG. 1, etc.).

Furthermore, in the case of this embodiment, a stent holding portion 48 (see FIG. 1, etc.) is provided on the outer circumference of the small diameter portion 41 . The stent holding portion 48 is formed to have a larger diameter than the small diameter portion 41 .
The stent holding portion 48 holds the stent 200 in the placement section 41a, and the stent holding portion 48 prevents the stent 200 from being displaced with respect to the placement section 41a as the outer tube portion 10 retreats or advances. Regulated.
More specifically, the stent holding portion 48 is, for example, a resin tube and is fitted onto the small diameter portion 41 . In addition, for example, an adhesive (not shown) is applied to the outer peripheral surface of the stent holding portion 48 and the vicinity of the arrangement area of the stent holding portion 48 in the arrangement section 41a. 41a.
The inner diameter of the stent holding portion 48 is set to be substantially equal to the outer diameter of the small diameter portion 41, and the outer diameter of the stent holding portion 48 is set to be smaller than the inner diameter of the outer tubular portion 10. It is set to a dimension larger than the inner diameter of the stent 200 in the diameter-reduced state. The stent 200 is held between the inner peripheral surface of the outer tube portion 10 and the outer peripheral surface of the narrow diameter portion 41 in a state in which a portion of the stent 200 in the longitudinal direction is externally inserted into the stent holding portion 48. there is More specifically, the portion of the stent 200 that is externally inserted into the stent holding portion 48 is sandwiched between the inner peripheral surface of the outer tube portion 10 and the outer peripheral surface of the stent holding portion 48. Axial displacement of the stent 200 relative to the arrangement section 41a as the outer tube portion 10 retreats or advances is regulated.
The length dimension (dimension in the axial direction) of the stent holding portion 48 is not particularly limited, but is preferably set appropriately according to the length dimension of the stent 200 .

The small-diameter portion 41 is made of, for example, fluorine-based thermoplastic polymer resin. The fluorine-based thermoplastic polymer material can be, but is not limited to, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), perfluoroalkoxy fluororesin (PFA), and the like. By forming the small diameter portion 41 from such a fluoropolymer material, sliding resistance when the guide wire 300 slides in the lumen of the small diameter portion 41 is reduced.
Also, the large-diameter portion 42 is integrally formed as a whole with, for example, a thermoplastic polymer material. The thermoplastic polymer materials include nylons such as polyimide (PI), polyamideimide (PAI), polyethylene terephthalate (PET), polyethylene (PE), polyamide (PA), polyamide elastomer (PAE), polyether block amide (PEBA). Elastomers, polyurethane (PU), ethylene-vinyl acetate resin (EVA), polyvinyl chloride (PVC) or polypropylene (PP) may be mentioned.
The large-diameter portion 42 may be, for example, a single tubular body configured by connecting tubular members that are formed separately from each other.

Although the outer diameter of the small diameter portion 41 is not particularly limited, it is preferably 0.1 mm or more and 2 mm or less. Although the inner diameter of the small-diameter portion 41 is not particularly limited, it is preferably 0.05 mm or more and 1 mm or less. The overall length of the small diameter portion 41 is not particularly limited, but is preferably 500 mm or more and 3000 mm or less.
Although the outer diameter of the large-diameter portion 42 is not particularly limited, it is preferably 1 mm or more and 6 mm or less. Although the inner diameter of the large-diameter portion 42 is not particularly limited, it is preferably 0.5 mm or more and 4 mm or less. The total length of the large-diameter portion 42 is not particularly limited, but is preferably 500 mm or more and 2500 mm or less.

The inner shaft 50 is formed, for example, in a tubular shape elongated in one direction. The large-diameter portion 42 and the inner shaft 50 are fixed to each other by press-fitting the distal end portion of the inner shaft 50 into the base end portion of the large-diameter portion 42 . The large-diameter portion 42 and the inner shaft 50 may be fixed to each other, for example, by adhesion or fusion.
In the case of this embodiment, a section of the inner shaft 50 that is exposed on the proximal side of the outer tube handle 20 in the initial state constitutes the protruding/retracting portion 54 .
The shaft handle 60 is formed, for example, in a cylindrical shape, is connected to the proximal end side of the large-diameter portion 42 , and has a series of lumens with the lumen of the large-diameter portion 42 . When using the stent delivery device 100 , for example, a physiological saline solution, a contrast medium, or the like can be injected into the lumen of the small diameter portion 41 through the opening on the proximal side of the shaft handle 60 .

The inner shaft 50 is made of, for example, a metal material such as stainless steel (SUS). Moreover, the shaft handle 60 is made of a resin material such as polyurethane or polyamide.

The outer diameter (maximum diameter) of the inner shaft 50 is not particularly limited, but is preferably 1 mm or more and 6 mm or less. Although the inner diameter of the inner shaft 50 is not particularly limited, it is preferably 0.5 mm or more and 3 mm or less. In addition, although the total length of the inner shaft 50 is not particularly limited, it is preferably 30 mm or more and 500 mm or less.

Here, as shown in FIG. 5, in the case of this embodiment, the outer tube handle 20 has a state in which the forward/backward movement of the outer tube handle 20 with respect to the inner shaft 50 is restricted, and a state in which the forward/backward movement of the outer tube handle 20 with respect to the inner shaft 50 is controlled. and a switching operation unit 30 capable of switching operation between the state in which
The switching operation portion 30 includes a ring member 33 made of an elastic material and through which the inner shaft 50 is inserted; a housing member 35 through which the inner shaft 50 is inserted and housing the ring member 33; and a threaded member 37 through which the shaft 50 is inserted and which is screwed to the housing member 35 .
In the case of this embodiment, the threaded member 37 is screwed into the housing member 35 and the ring member 33 is compressed between the housing member 35 and the threaded member 37 , whereby the switching operation portion 30 advances and retreats with respect to the inner shaft 50 . is regulated, and the outer diameter of the ring member 33 is reduced in the direction in which the threaded member 37 is screwed into the accommodating member 35 .
As a result, the forward/backward movement of the outer tube handle 20 with respect to the inner shaft 50 can be appropriately regulated, so that unintentional movement of the outer tube handle 20 can be suppressed, and the outer tube handle 20 can be moved at a desired timing and retraction amount. It becomes easy to retreat to the shaft handle 60 side. Therefore, it is possible to easily achieve the intended placement operation of the stent 200 .

The ring member 33 is formed, for example, in a substantially cylindrical shape whose axial direction is the tip-to-base end direction, and the inner shaft 50 is inserted through the inner cavity of the ring member 33 . The inner diameter of the ring member 33 in the natural state is, for example, set substantially equal to the outer diameter of the inner shaft 50 .
The elastic body forming the ring member 33 is not particularly limited, but may be, for example, an elastic material such as silicone rubber or elastomer.

The housing member 35 is formed in a cylindrical shape having a spiral direction as an axial direction. The inner shaft 50 is inserted through the inner cavity of the housing member 35 and is slidable relative to the housing member 35 in the axial direction of the housing member 35 .
More specifically, as shown in FIG. 6A, the accommodation member 35 includes, for example, a body portion 35a into which the screw member 37 is screwed, and an operation receiving portion 35b that receives a switching operation.
Each of the main body portion 35a and the operation receiving portion 35b is formed in a cylindrical shape whose axial direction is the tip-to-base end direction. Further, the main body portion 35a and the operation receiving portion 35b are arranged coaxially with each other.
The inner diameter of the main body portion 35a is smaller than the inner diameter (maximum diameter) of the operation receiving portion 35b, and the outer diameter of the main body portion 35a is smaller than the outer diameter of the operation receiving portion 35b.
Further, the inner lumen of the proximal end portion of the operation receiving portion 35b is formed to have a smaller diameter than the inner lumen of the other portions, and the inner lumen of the operation receiving portion 35b includes a large diameter portion and a small diameter portion. The ring member 33 is accommodated in the large diameter portion of the lumen of the operation receiving portion 35b. A portion of the inner peripheral surface of the operation receiving portion 35b forms a stepped surface facing the distal end side at the boundary between the large diameter portion and the small diameter portion of the lumen of the operation receiving portion 35b. The stepped surface of the operation receiving portion 35 b has an annular shape when viewed in the axial direction, and the stepped surface faces the tip end surface of the ring member 33 .
Further, as shown in FIG. 5, on the outer peripheral surface of the operation receiving portion 35b, for example, a plurality of grooves extending in the axial direction are intermittently arranged in the circumferential direction of the operation receiving portion 35b. The plurality of grooves and the portions between the adjacent grooves form a plurality of irregularities alternately arranged in the circumferential direction.

The threaded member 37 is formed in a cylindrical shape having a threaded direction as an axial direction. The inner shaft 50 is inserted through the inner cavity of the threaded member 37 and is slidable relative to the threaded member 37 in the axial direction of the threaded member 37 .
More specifically, as shown in FIGS. 6(a) and 6(b), the threaded member 37 includes, for example, a threaded portion 37a threadedly engaged with the housing member 35 and a threaded portion 37a. and an insertion portion 37b inserted into the lumen of the body portion 35a of the housing member 35 .
Each of the threaded portion 37a and the insertion portion 37b is, for example, formed in a cylindrical shape whose axial direction is the tip-to-base end direction, and arranged coaxially with each other. The proximal end of the threaded portion 37a is connected to the distal end of the insertion portion 37b. Further, the inner cavity of the threaded portion 37a and the inner cavity of the insertion portion 37b communicate with each other. The outer diameter of the threaded portion 37a is set to be, for example, larger than the outer diameter of the insertion portion 37b, and the inner diameter of the threaded portion 37a is set to be substantially equal to the inner diameter of the insertion portion 37b. ing.
As shown in FIG. 6B, the outer shape of the flange portion 37c when viewed in the axial direction of the flange portion 37c is, for example, a regular hexagonal shape, and the outer peripheral surface of the flange portion 37c is composed of six surfaces. , and the six planes are formed in planes orthogonal to the axial direction.
The dimension of the flange portion 37c in the radial direction is larger than the outer diameter of the threaded portion 37a.

In the case of this embodiment, the threaded member 37 is screwed into the housing member 35 from the distal end side. The portion 37a is a male screw portion. Further, a screw thread is formed on the inner peripheral surface of the main body portion 35a, and the main body portion 35a is a female screw portion. The threaded member 37 and the housing member 35 are connected to each other by screwing the female threaded portion and the male threaded portion together. The ring member 33 is arranged between the proximal end surface of the threaded portion 37a and the stepped surface of the operation receiving portion 35b.
In addition, the inner shaft 50 is inserted through the inner cavity of the threaded member 37 and the inner cavity of the housing member 35 . The inner shaft 50 protrudes distally from the distal end side opening of the threaded member 37 and protrudes proximally from the proximal side opening of the housing member 35 .

Each of the housing member 35 and the threaded member 37 is made of, for example, a hard resin material. Although the resin material is not particularly limited, examples thereof include polyolefins such as polyethylene and polypropylene, polyamide, polycarbonate, and polystyrene. The housing member 35 and the threaded member 37 may be made of the same kind of resin material, or may be made of different resin materials.

Here, inside the outer tube handle 20, a pair of holding portions 25 for holding the threaded member 37 and a housing portion 26 for housing the housing member 35 are formed.
The pair of holding portions 25 restricts rotation of the threaded member 37 with respect to the outer tube handle 20 , while the accommodating portion 26 allows rotation of the accommodating member 35 with respect to the outer tube handle 20 . As shown in FIG. 5 , the pair of holding portions 25 are arranged, for example, on the distal end side of the accommodating portion 26 .
In the case of the present embodiment, by rotating the accommodating member 35 of the screwing member 37 and the accommodating member 35, the screwing member 37 moves in the spiral direction.

More specifically, each of the pair of holding portions 25 is constituted by a pair of flat plate-like wall portions erected on the inner surface of the first member 22a. Each of the pair of wall portions is arranged with the flange portion 37c of the screw member 37 interposed therebetween. More specifically, one of the six surfaces forming the outer peripheral surface of the flange portion 37c is in surface contact with one wall portion of the pair of wall portions. and parallel surfaces are in surface contact with the other wall portion of the pair of wall portions.
Therefore, the threaded member 37 is held by the pair of holding portions 25 in a state in which the threaded member 37 is allowed to move in the direction of the proximal end while the rotation of the threaded member 37 is restricted. . However, in the case of the present embodiment, on the inner surface of the first member 22a, between the pair of holding portions 25, there is provided a restricting plate that restricts movement of the threaded member 37 to the distal end side of the holding portion 25. 27 is formed. As a result, movement of the threaded member 37 to the proximal end side relative to the restricting plate 27 is restricted.
The shape of the flange portion 37c viewed in the direction of the proximal end is not particularly limited as long as the outer peripheral surface thereof has a pair of surfaces facing each other.
Also, such a pair of holding portions 25 may be formed, for example, at positions corresponding to the holding portions 25 of the first member 22a on the inner surface of the second member.

In the case of this embodiment, four walls are erected on the inner surface of the first member 22a. An assembly of these four wall portions forms a frame-shaped accommodation portion 26 that is substantially rectangular in side view. Two notch-shaped portions 26a are formed in the housing portion 26. One of the two notch-shaped portions 26a allows passage to the distal end side of the main body portion 35a, and the other is the inner shaft. 50 is allowed to pass proximally. As a result, the housing member 35 is rotatable about the axis with respect to the outer tube handle 20 while being housed inside the housing portion 26 . Then, the user can perform the switching operation, for example, by rotating the operation receiving portion 35b about its axis.
Note that such a housing portion 26 may also be formed, for example, at a portion corresponding to the housing portion 26 of the first member 22a on the inner surface of the second member 22b.
Here, in each of the first member 22a and the second member 22b, the portion corresponding to the operation receiving portion 35b has an opening that allows the internal space of the outer tube handle 20 and the outside of the outer tube handle 20 to communicate with each other. A portion 22c (see FIG. 1) is formed. At least a portion of the operation receiving portion 35b in the circumferential direction can be accessed by the user's fingers from the outside of the outer tube handle 20 through the opening 22c. Part of the operation receiving portion 35b may or may not protrude to the outside of the outer tube handle 20 through the opening 22c.
The opening 22c is formed in, for example, a substantially rectangular shape when viewed from the side.

In the case of this embodiment, the screwing direction in which the screwing member 37 is screwed into the housing member 35 is the proximal direction.
More specifically, the operation of rotating the operation receiving portion 35b of the housing member 35 in one direction in the circumferential direction relative to the outer tube handle 20 (hereinafter referred to as the closing operation) causes the outer tube handle 20 to move forward and backward with respect to the inner shaft 50. can be switched to a regulated state. Along with the closing operation, the screwing member 37 is screwed into the accommodating member 35 and is screwed from the distal end side to the proximal end side. At this time, as the screwing member 37 is screwed, the stepped surface of the operation receiving portion 35b and the end surface of the screwing portion 37a of the screwing member 37 on the proximal side approach each other in the screwing direction. It will happen. As a result, the ring member 33 disposed between the stepped surface of the operation receiving portion 35b and the end surface on the base end side of the threaded portion 37a is elastically deformed by being pressed by the surfaces, and moves in the axial direction. It is in a compressed state, and the inner diameter of the ring member 33 is reduced. Then, by further performing the closing operation, the inner shaft 50 can be in a state in which it is circularly tightened by the ring member 33 that is compressed in the distal and proximal direction.
Further, by rotating the operation receiving portion 35b of the housing member 35 relative to the screwing member 37 in the other direction in the circumferential direction (opposite direction to the rotation direction in the closing operation) (hereinafter referred to as opening operation), the inner It is possible to switch to a state in which the outer tube handle 20 can move back and forth with respect to the shaft 50 . With the opening operation, the screwing member 37 moves toward the distal end side, the ring member 33 is released from the compressed state, and the switching operation portion 30 can move forward and backward with respect to the inner shaft 50 .
Here, as described above, the regulating plate 27 is arranged between the pair of holding portions 25 holding the screwing member 37 . The abutment of the threaded member 37 against the restricting plate 27 prevents the housing member 35 and the threaded member 37 from being completely disengaged.
The threading direction of the threaded member 37 is not limited to the distal side to the proximal side, and the threaded member 37 may be configured to thread from the proximal side toward the distal side. In this case, the positional relationship between the housing member 35 and the threaded member 37 is reversed in the distal-to-basal direction.

An example of how to use the stent delivery device 100 of this embodiment will be described below.
As an example, an example in which the stent delivery device 100 is used in a procedure for placing the stent 200 inside a bile duct (not shown) will be described below.
Note that the distal end portion of the insertion portion of the endoscope 400 (see FIG. 8) is previously placed in the duodenum (not shown) near the papilla of the duodenum (Papilla of Vater) and the bile duct (not shown). ), and the distal end of the guide wire 300 is anchored (locked) to the needle hole.
First, the stent delivery device 100 is introduced along the guidewire 300 . More specifically, the small-diameter portion 41 of the inner tube portion 40 is fitted over the guidewire 300, and the inner tube portion 40 is slid from the proximal side to the distal side along the axial direction of the guidewire. 40 and the outer tube portion 10 are fed into the needle hole. At this time, the forward/backward movement of the outer tube handle 20 with respect to the inner shaft 50 is restricted by the switching operation portion 30 . Next, when the placement section 41a of the stent 200 in the inner tube portion 40 is inserted into the bile duct, the stent 200 is placed. More specifically, first, the switching operation unit 30 switches to a state in which the outer tube handle 20 can move back and forth with respect to the inner shaft 50 . Then, while holding the shaft handle 60 with one hand, the other hand retracts the outer tube handle 20 together with the outer tube portion 10 toward the shaft handle 60, thereby moving the distal end portion 40b of the inner tube portion 40 to the outer tube. It is exposed from the portion 10 (see FIGS. 9(a) and 10(a)). Subsequently, by retracting the outer tube handle 20 until the entire arrangement section 41a of the stent 200 in the inner tube section 40 is exposed from the outer tube section 10, the entire stent 200 is changed from the diameter-reduced state to the deployed state. (See FIGS. 9(c) and 10(c)).
Then, while the outer tube handle 20 is advanced together with the outer tube section 10 until the distal end of the outer tube section 10 abuts on the distal tip, the switching operation section 30 again moves the outer tube handle 20 forward and backward relative to the inner shaft 50 . Switch to regulated state. In this state, the inner tube part 40 and the outer tube part 10 are removed from the body cavity, and the guide wire 300 is also removed from the body cavity.
In the case of this embodiment, when the stent 200 is placed, the distal end portion 40b of the inner tube portion 40 is exposed from the outer tube portion 10, and the stent holding portion 48 is housed inside the outer tube portion 10. 9(b) and 10(b)), when the outer tube handle 20 is advanced, the outer tube portion 10 is advanced relative to the stent 200, and the stent 200 is moved toward the outer tube. It can be re-stored in section 10. As a result, for example, even if the deployment of the stent 200 is unintentionally started at a position other than the desired position in the body cavity, the stent 200 can be stored in the outer tube part 10 again, and the outer tube part 10 and The position of stent 200 in the body lumen can be adjusted with inner tube 40 .

The present invention is not limited to the above embodiments, and includes various modifications, improvements, and other aspects as long as the object of the present invention is achieved.

This embodiment includes the following technical ideas.
(1) an outer tube;
an outer tube handle to which a proximal end portion of the outer tube portion is fixed;
an inner tube portion axially slidably inserted through the outer tube portion;
an inner shaft integrated with the inner tube portion and extending proximally from the outer tube handle;
a shaft handle to which the proximal end of the inner shaft is fixed;
with
By retracting the outer tube handle together with the outer tube toward the shaft handle, the distal end of the inner tube is exposed from the outer tube, and the stent held by the inner tube is left in the body cavity. is possible and
The outer tube portion has a proximal side portion and a distal side portion connected to the distal side of the proximal side portion,
The base end portion is configured using a first resin material as a base material,
The tip side portion is configured using a second resin material having a hardness lower than that of the first resin material as a base material,
a protruding portion in which a boundary line between the distal side portion and the proximal side portion protrudes toward the distal side in the circumferential direction of the boundary portion between the distal side portion and the proximal side portion; There is a recessed part that is convex on the proximal side,
The outer tube portion includes a reinforcing layer formed in a mesh shape by braided metal wires,
a series of reinforcing layers extending from the proximal portion to the distal portion;
Regarding the protruding portion and the recessed portion adjacent to each other in the circumferential direction of the boundary,
In the axial direction of the outer tube portion, the differential dimension between the maximum projecting portion of the projecting portion and the maximum recessed portion of the recessed portion is smaller than the dimension of one mesh opening of the reinforcing layer. Device.
(2) The stent delivery device according to (1), in which the plurality of protruding portions and the plurality of recessed portions are repeatedly present in the circumferential direction of the boundary portion.
(3) The stent delivery device according to (1) or (2), wherein the differential dimension is larger than the dimension of half the opening of the mesh.

10 Outer tube portion 10a Base end portion 10b Tip portion 11 Marker member 12 Boundary portion 12a Protruding portion 12b Recessed portion 14 Inner layer 15 Outer layer 16 Reinforcing layer 16a Mesh 17 Tip side portion 18 Base end portion 19 Fixing ring member 20 Outer tube Handle 22a First member 22b Second member 22c Opening 23 Accommodating recess 24c Notch-shaped portion 25 Holding portion 26 Accommodating portion 26a Notch-shaped portion 27 Regulating plate 30 Switching operation portion 33 Ring member 35 Accommodating member 35a Body portion 35b Operation receiving portion 37 Screwing member 37a Screwing part 37b Insertion part 37c Flange part 40 Inner tube part 40a Base end part 40b Tip part 41 Small diameter part 42 Large diameter part 43 Tip tip 46 Endoscope visual recognition marker 46a Adhesive 48 Stent holding part 50 Inside Shaft 54 Protruding portion 60 Shaft handle 100 Stent delivery device 200 Stent 300 Guide wire 400 Endoscope

Claims (3)

an outer tube;
an outer tube handle to which a proximal end portion of the outer tube portion is fixed;
an inner tube portion axially slidably inserted through the outer tube portion;
an inner shaft integrated with the inner tube portion and extending proximally from the outer tube handle;
a shaft handle to which the proximal end of the inner shaft is fixed;
with
By retracting the outer tube handle together with the outer tube toward the shaft handle, the distal end of the inner tube is exposed from the outer tube, and the stent held by the inner tube is left in the body cavity. is possible and
The outer tube portion has a proximal side portion and a distal side portion connected to the distal side of the proximal side portion,
The base end portion is configured using a first resin material as a base material,
The tip side portion is configured using a second resin material having a hardness lower than that of the first resin material as a base material,
a protruding portion in which a boundary line between the distal side portion and the proximal side portion protrudes toward the distal side in the circumferential direction of the boundary portion between the distal side portion and the proximal side portion; There is a recessed part that is convex on the proximal side,
The outer tube portion includes a reinforcing layer formed in a mesh shape by braided metal wires,
a series of reinforcing layers extending from the proximal portion to the distal portion;
Regarding the protruding portion and the recessed portion adjacent to each other in the circumferential direction of the boundary,
In the axial direction of the outer tube portion, the differential dimension between the maximum projecting portion of the projecting portion and the maximum recessed portion of the recessed portion is smaller than the dimension of one mesh opening of the reinforcing layer. Device. 2. The stent delivery device according to claim 1, wherein a plurality of said projecting portions and a plurality of said recessed portions are repeatedly present in the circumferential direction of said boundary portion. 3. The stent delivery device according to claim 1 or 2, wherein the differential dimension is larger than the dimension of half of the opening of the mesh.

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