JP6937042B2 - Tube stent delivery system - Google Patents

Description

The present invention relates to a tube stent delivery system used for bile duct, pancreatic duct drainage, and the like.

A tube stent delivery system including a tube stent, an inner catheter and an outer catheter is known.

For example, in Patent Document 1, a filamentous body provided with a hump-like body is attached to an end by being tied through a hole provided in the radial direction of a pusher catheter (outer catheter) or a tube stent, and an inner catheter is provided. It is a tube stent delivery system that maintains the loose fitting state of the hump-like body and the locking hole. With a simple structure, the connection state between the tube stent and the pusher catheter is not easily released, and the connection state is maintained. It is disclosed that it is easy to release when you want to release it.

Japanese Unexamined Patent Publication No. 2012-239803

The above-mentioned Patent Document 1 describes that the outer catheter and the tube stent are connected by a filament. However, with the progress of surgery using an endoscope, inner catheters having various outer diameters have been used, and there is a problem that the tube stent tends to come off during internal movement. In particular, when the outer diameter of the inner catheter is small, there is a problem that the bond between the outer catheter and the tube stent becomes loose and the tube stent becomes easier to come off.

In view of the above circumstances, it is an object of the present invention to provide a highly versatile tube stent delivery system in which the tube stent does not easily come off during in-vivo movement.

As a result of diligent research on the above-mentioned problems, the inventor of the present invention has found the following epoch-making tube stent delivery system.

The first aspect of the present invention for solving the above problems is an inner catheter, a middle catheter into which the inner catheter is inserted, an outer catheter into which the middle catheter is inserted, and a middle catheter in which the distal end side of the inner catheter is inserted. A tube stent having a joint to be joined to the catheter and a tube stent delivery system characterized in that the inner diameter of the joint is smaller than the outer diameter of the middle catheter.

In the first aspect, since the tube stent and the middle catheter are joined by friction at the joint portion, the tube stent does not easily come off during movement in the body, and the tube stent can be reliably transported to the target site.

Even when the outer diameter of the inner catheter is small (for example, the diameter is 10 French or less, especially 5 French or less), the inner catheter is surrounded by the middle catheter, so that the strength can be maintained and the inner catheter can maintain its strength during internal movement. It is possible to prevent the tube stent from being easily detached. As a result, the present embodiment can be adapted to various inner catheters having different outer diameters, and can provide a highly versatile tube stent delivery system.

In addition, the middle catheter allows the distance between the outer catheter and the tube stent to be smaller (the axis of the outer catheter and the tube stent axis can be prevented from shifting), so that their axial changes during in-vivo movement. (Even if the tube stent or outer catheter is bent), the opposite end on the distal end side of the tube stent and the distal end on the outer catheter can be reliably brought into contact with each other. As a result, the tube stent can be reliably pushed by the tip of the outer catheter.

Further, it is possible to provide a highly versatile tube stent delivery system in which the tube stent does not easily come off. In particular, it is possible to provide a highly versatile tube stent delivery system in which the tube stent does not easily come off even when an inner catheter having a small outer diameter (for example, a diameter of 10 French or less, particularly 5 French or less) is used.

The tube stent delivery according to the first aspect, wherein the second aspect according to the present invention is provided with a small diameter portion having a small outer diameter of the inner catheter on the distal end side of the inner catheter. In the system.

In such a second aspect, the small diameter portion of the inner catheter is less rigid than the other portion of the inner catheter and is therefore easily flexed from the portion surrounded by the tube stent as the guide wire moves. be able to. As a result, the operability of the tube stent delivery system is improved, and stable movement within the body can be performed.

Further, the tube stent delivery system of this embodiment can easily pass through the mesh even in a mesh-like stent such as a stent-in-stent described later, and can be applied to various drainage applications. In addition, the force of insertion within the stenosis site is reduced, facilitating operability regarding passage through the stenosis site.

A third aspect of the present invention is the tube stent delivery system according to the second aspect, wherein the outer diameter of the small diameter portion becomes smaller toward the tip end portion of the inner catheter.

In the third aspect, the small diameter portion of the inner catheter becomes more easily bent with the movement of the guide wire because the rigidity of the inner catheter becomes smoother toward the tip portion. Can be done. As a result, the operability of the tube stent delivery system is further improved, and more stable movement in the body can be performed.

A fourth aspect of the present invention is in the tube stent delivery system according to the second aspect, wherein the small diameter portion is tapered.

In the fourth aspect, the small diameter portion of the inner catheter becomes more easily bent with the movement of the guide wire because the rigidity of the inner catheter becomes smoother toward the tip portion. Can be done. As a result, the operability of the tube stent delivery system is further improved, and more stable movement in the body can be performed.

In addition, the tube stent delivery system of this embodiment can pass through the mesh more easily even in the mesh-like stent, and can be adapted to various drainage applications. In addition, the force of insertion within the stenosis site is further reduced, facilitating operability regarding passage through the stenosis site.

A fifth aspect of the present invention is the tube stent delivery system according to any one of the second to fourth aspects, wherein at least a part of the small diameter portion is surrounded by a tube stent. ..

In such a fifth aspect, the tube stent delivery system can suppress the displacement of the small diameter portion, enable stable movement in the body, and easily pass through the body tube deformed at various angles. The operability of the

It is a side view which shows an example of the tube stent delivery system which concerns on Embodiment 1. FIG. The inner catheter of FIG. 1 is shown, and is a side view (a), a cross-sectional view taken along the line AA of (b) and (a), and a cross-sectional view taken along the line BB of (c) and (a). The tube stent of FIG. 1 is shown, and is a side view (a), a cross-sectional view taken along the line AA of (b) and (a), and a cross-sectional view taken along the line BB of (c) and (a). The outer catheter of FIG. 1 is shown, and is a side view (a) and a cross-sectional view taken along the line AA of (b) and (a). A middle catheter according to the first embodiment is shown, and is a side view (a) and a cross-sectional view taken along the line AA of (b) and (a). FIG. 5 is an exploded cross-sectional view showing the relationship between the inner catheter, the tube stent, the outer catheter, and the middle catheter according to the first embodiment. FIG. 5 is an exploded cross-sectional view showing the relationship between the inner catheter, the tube stent, the outer catheter, and the middle catheter according to the first embodiment. It is a partial side view which shows the relationship of the inner catheter, the tube stent, the outer catheter, and the middle catheter which concerns on another embodiment of Embodiment 1. It is a schematic diagram explaining the use state in the body of the tube stent delivery system which concerns on Embodiment 1. FIG. It is a schematic diagram explaining the relationship between the tube stent delivery system and the expansion stent which concerns on Embodiment 1. FIG.

An embodiment of the tube stent delivery system according to the present invention will be described below with reference to the accompanying drawings. The present invention is not limited to the following embodiments.
(Embodiment 1)

FIG. 1 is a side view showing a tube stent delivery system according to the present embodiment. 2A and 2B show the inner catheter of FIG. 1, where FIG. 2A is a side view, FIG. 2B is a cross-sectional view taken along the line AA of FIG. 3A and 3B show the tube stent of FIG. 1, FIG. 3A is a side view, FIG. 3B is a cross-sectional view taken along the line AA of FIG. 4A and 4B show the outer catheter of FIG. 1, where FIG. 4A is a side view and FIG. 4B is a cross-sectional view taken along the line AA of FIG. 1A. FIG. 5 shows a middle catheter according to the present embodiment, and is a side view (a) and a cross-sectional view taken along the line AA of (b) and (a). FIG. 6 is an exploded cross-sectional view showing the relationship between the inner catheter, the tube stent, the outer catheter, and the middle catheter according to the present embodiment. FIG. 7 is an exploded cross-sectional view showing the relationship between the inner catheter, the tube stent, the outer catheter, and the middle catheter according to the present embodiment. FIG. 8 is a partial side view showing the relationship between the inner catheter, the tube stent, the outer catheter, and the middle catheter according to another embodiment of the present embodiment. The tube stent delivery system 1 will be described in detail with reference to FIGS. 1 to 8.

As shown in FIG. 1, the tube stent delivery system 1 of the present invention includes an inner catheter 10, a tube stent 20, an outer catheter 30, and a middle catheter 40. In this figure, the middle catheter 40 is shown by a broken line.

As shown in FIG. 2, the inner catheter 10 includes an inner catheter tube wall portion 11 having an annular shape, an inner catheter insertion portion 12 surrounded by the inner catheter tube wall portion 11 and a cavity, and a connector operated by a doctor or the like at one end. , An operation unit 50 provided with an endoscope or the like, and an inner catheter opening 13 provided at one end opposite to the operation unit 50.

Hereinafter, the direction of one end opposite to the operation unit 50 will be described as the distal end side, and the tube stent 20 and the outer catheter 30 will also be described as the distal end side. Further, the tip of the inner catheter 10 will be referred to as a tip portion 14.

The tube stent 20 is to be placed at a target site in the body, and as shown in FIG. 3, a stent tube wall portion 21 having an annular shape, a hollow stent insertion portion 22 surrounded by the stent tube wall portion 21, and a stent insertion portion 22 are provided. Flap portions 23 arranged on both sides of the tube stent 20 and stent openings 24 opened at both ends are provided.

As shown in FIG. 4, the outer catheter 30 has an outer catheter tube wall portion 31 having an annular shape, a hollow outer catheter insertion portion 32 surrounded by the outer catheter tube wall portion 31, and an opening on the distal end side of the outer catheter 30. The outer catheter opening 33 is provided.

As shown in FIG. 5, the middle catheter 40 is formed at the middle catheter tube wall portion 41 having an annular shape, the hollow middle catheter insertion portion 42 surrounded by the middle catheter tube wall portion 41, and the end of the middle catheter 40. It is provided with an opened middle catheter opening 43.

The middle catheter 40 is integrally attached to the outer catheter 30 and has a coupling structure that does not easily separate from the outer catheter 30. Examples of this bonding structure include mechanical bonding such as engagement and chemical bonding such as adhesive. In the present embodiment, the outer catheter 30 and the middle catheter 40 are separately molded, but may be integrally molded. Further, the middle catheter 40 may be arranged over the entire length of the outer catheter 30, and one end thereof may be attached to the operation unit 50 in the same manner as the outer catheter 30.

As shown in FIG. 1, the tube stent delivery system 1 is a system in which the above-mentioned inner catheter 10, tube stent 20, outer catheter 30, and middle catheter 40 are integrated. In the present embodiment, the middle catheter 40 is inserted into the outer catheter insertion portion 32 of the outer catheter 30, and a part of the distal end side of the middle catheter 40 is arranged so as to protrude from the distal end side of the outer catheter 30. Then, the protruding portion is inserted into the tube stent 20. When the middle catheter 40 and the outer catheter 30 are integrally molded, the middle catheter 40 is in a state of protruding toward the distal end side of the outer catheter 30.

Here, since the total length of the inner catheter 10 is longer than the total length of the outer catheter 30, when the inner catheter 10 is inserted into the outer catheter 30 and the middle catheter 40, the distal end side of the inner catheter 10 protrudes from the distal end side of the outer catheter 30. do. When the protruding portion is inserted into the stent insertion portion 22, the stent opening 24 on the opposite side of the distal end side of the tube stent 20 and the outer catheter opening 33 come into contact with each other or come into close contact with each other. Since the length of the portion of the inner catheter 10 protruding from the distal end side of the outer catheter 30 is longer than the total length of the tube stent 20, the inner catheter 10 is arranged in a partially protruding state on the distal end side of the tube stent 20. When the middle catheter 40 is arranged over the entire length of the outer catheter 30, the total length of the middle catheter 40 is longer than the total length of the outer catheter 30.

The inner catheter 10, the tube stent 20, the outer catheter 30, and the middle catheter 40 are molded from a flexible resin material (for example, polyethylene, polyurethane, polyamide, etc.), but the material is not particularly limited.

The shape of the tube stent 20 is not particularly limited, and examples thereof include a straight type, an inside type, and a double pigtail type. Further, the shape of the inner catheter 10 is not particularly limited, and examples thereof include an α type, a J type, and a pigtail type.

Next, the joint portion of the tube stent 20, the middle catheter 40, and the outer catheter 30 will be described. As shown in FIG. 6, the stent insertion portion 22 of the tube stent 20 is provided with a junction portion 25 for joining with the middle catheter 40. The joint portion 25 has an inner diameter L, which is smaller than the outer diameter M of the middle catheter 40. That is, when the middle catheter 40 is inserted into the tube stent 20, the stent insertion portion 22 is in a state of being pressed against the middle catheter tube wall portion 41 at the joint portion 25. As a result, friction occurs between the stent insertion portion 22 and the middle catheter tube wall portion 41, and the tube stent 20 is prevented from being detached from the middle catheter 40. In the present embodiment, the joint portion 25 is provided on a part of the tube stent 20, but it may be provided over the entire length of the tube stent 20, and the length of the joint portion 25 is not limited. In FIG. 6, the inner catheter 10 is shown by a broken line.

Here, the relationship between the inner diameter L and the outer diameter M is the case where the inner diameter L is over the entire length of the tube stent 20 and the inner diameter of the tube stent is smaller than the outer diameter M of the middle catheter 40, as shown in FIG. Is also included. In such a case, when the middle catheter 40 is inserted into the tube stent 20, the inner diameter of the tube stent 20 is widened to be larger than L, and as a result, the tube stent 20 in the portion where the middle catheter 40 is inserted is inserted. A state in which the inner diameter is M or about M is also included. In this case, the stent tube wall portion 21 of the portion where the middle catheter 40 of the tube stent 20 is inserted becomes the joint portion 25.

In the present embodiment, as shown in FIG. 2, the inner catheter 10 has an outer diameter D1, but includes a small diameter portion 15 having an outer diameter D2 having a small outer diameter D1. As shown in this figure, the outer diameter of the inner catheter tube wall portion 11 is D1 in the AA cross section, but the outer diameter D2 of the small diameter portion 15 and D1> in the BB cross section near the tip. It has a D2 relationship. However, the outer diameters D1 and D2 are not exact values and include molding errors, shape displacements, and the like.

The shape is not particularly limited as long as the outer diameter D2 is smaller than the outer diameter D1 of the inner catheter 10. The shape of the small diameter portion 15 includes various shapes, for example, the outer diameter D2 becomes smaller toward the tip portion 14, the outer diameter D2 becomes smaller gradually and gradually, and the shape is tapered on the cross section. In, the gradient angles of both sides are the same, different, and the like. In the tapered shape, a two-step taper having two different taper angles may be used, but a plurality of taper angles of three or more may be provided, and the taper shape is not particularly limited to two steps. The outer diameter D2 may be partially varied, but it is preferably the smallest at the tip portion 14.

The small diameter portion 15 may be formed by using a mold or may be deformed by using heat, but it is preferable that the small diameter portion 15 maintains a predetermined inner diameter over the entire length of the inner catheter 10. The inner catheter insertion portion 12 needs to be inserted with a guide wire to be arranged in the body in advance, and is preferably suitable for the outer diameter of the guide wire to be used. For example, the length of the small diameter portion 15 is 25 mm ± 5 mm, the inner diameter is 0.025 inch, and the like.

The portion where the formation of the small diameter portion 15 is started is closer to the distal end side (closer to the distal end) than the vicinity of the center, and as shown in FIG. 8, at least a part of the small diameter portion 15 is surrounded by the stent tube wall portion 21. There is. Since the small diameter portion 15 is thinner than the other portions of the inner catheter 10, it has low rigidity and is easily bent, but it is supported by the stent tube wall portion 21 during internal movement and can stably move to the target site. ..

As shown in FIG. 3, the tube stent 20 generally has an outer diameter F1, but an outer diameter F2 smaller than the outer diameter F1 is provided on the distal end side in accordance with the small diameter portion 15 of the inner catheter 10. The stent small diameter portion 26 to have may be provided. In the AA cross section, the outer diameter of the stent tube wall portion 21 is F1, but in the BB cross section near the tip, the outer diameter of the stent small diameter portion 26 is F2, and there is a relationship of F1> F2. However, the outer diameters F1 and F2 are not exact values and include molding errors, shape displacements, and the like.

Further, it is preferable that at least a part of the small diameter portion 15 of the inner catheter 10 is surrounded by the small diameter portion 26 of the stent. Since the outer circumference of the small diameter portion 15 of the inner catheter 10 is positioned so as to be in contact with the stent tube wall portion 21 of the tube stent 20, the displacement of the inner catheter due to the movement of the inner catheter 10 in the body is suppressed, and the displacement of the inner catheter is suppressed. The follow-up movement of the tube stent 20 with respect to the inner catheter 10 becomes smooth.

The shape of the stent small diameter portion 26 is not particularly limited as long as the outer diameter F2 is smaller than the outer diameter F1 of the stent. The shape of the stent small diameter portion 26 includes various shapes, for example, the outer diameter F2 becomes smaller toward the tip, the outer diameter F2 becomes smaller gradually and gradually, and the stent is tapered in cross section. , The slope angles on both sides are the same, different, and so on. In the tapered shape, a two-step taper having two different taper angles may be used, but a plurality of taper angles of three or more may be provided, and the taper shape is not particularly limited to two steps. The outer diameter F2 may be partially varied, but it is preferably the smallest diameter at the tip.

The small diameter portion 26 of the stent may be formed by using a mold or may be deformed by using heat, but has a predetermined inner diameter that easily contacts the outer periphery of the inner catheter 10 over the entire length of the tube stent 20. It is preferable to maintain it.

The tube stent delivery system 1 according to the present embodiment fits the tube stent 20 on the distal end side of the inner catheter 10, and for example, in order to perform bile duct and pancreatic duct drainage, the purpose in the body together with the tube stent 20 in combination with an endoscope. Allow to stand at a site (eg, a stenotic site). In particular, the tube stent delivery system 1 of the present embodiment is easily inserted into the narrowed portion by the small diameter portion 15. Further, if the outer diameter D2 becomes smaller toward the tip, force and torque are likely to be applied to the tip 14 of the inner catheter at the time of insertion and passage into the constricted portion. Then, after pulling out the guide wire, the tube stent delivery system 1 is allowed to stand in the body for a predetermined period, and in a state where it is determined that body fluid such as bile is stably discharged, the inner catheter 10 is pulled out and the tube stent is pulled out. 20 is reserved at the target site.

Further, since a frictional force is generated between the inner surface of the tube stent 20 and the outer surface of the middle catheter 40, the tube stent 20 can be easily detached from the inner catheter 10 even if the tube stent delivery system 1 is inserted into the body. There is no. Therefore, it is easy to adjust the position with respect to the target site, and the burden on the patient is reduced.

Further, when the outer diameter of the inner catheter 10 is small (for example, the diameter is 10 French or less, particularly 5 French or less), it is easy to bend, but since it is surrounded by the middle catheter 40, the strength (rigidity) can be improved. can.

Further, since the middle catheter 40 is inserted into the tube stent 20, the distance between the outer catheter 30 and the tube stent 20 can be reduced (the axis of the outer catheter and the tube stent axis can be prevented from being displaced). (Can be done), so even with those axial changes during internal movement (even if the tube stent or outer catheter bends), the opposite end on the distal end of the tube stent and the distal end of the outer catheter It can be reliably contacted. As a result, the tube stent 20 can be reliably pushed by the tip of the outer catheter 30.

As shown in FIG. 8, in the tube stent delivery system 1, the inner catheter 10 is inserted into the outer catheter insertion portion 32 of the outer catheter 30 and the middle catheter insertion portion 42 of the middle catheter 40, and the tube is placed on the distal end side of the inner catheter 10. The tube stent delivery system 1 is configured with the inner catheter 10 inserted through the stent insertion portion 22 of the stent 20. At this time, the middle catheter 40 is inserted into the joint portion 25 of the tube stent 20. Then, the tube stent delivery system 1 in this state is inserted into the body.

At that time, the stent opening 24 on the opposite side of the distal end side of the tube stent 20 and the outer catheter opening 33 are in contact with each other or in close proximity to each other. Then, when the tube stent 20 is placed at the target site, when the inner catheter 10 is pulled out from the tube stent 20 with respect to the tube stent delivery system 1 stationary at the target site in the body, the outer catheter opening 33 becomes the tube stent 20. Since the stent opening 24 on the opposite side of the tip side is pushed, the tube stent 20 can be easily placed at the target site.

Next, the usage state of the tube stent delivery system 1 of the present embodiment in the body will be described with reference to FIG.

The tube stent delivery system 1 can transport the tube stent 20 to a target site in the body in combination with an endoscope. In advance, a guide wire (not shown) is introduced into the bile duct, for example, through a channel of the endoscope, and the tip of the guide wire is inserted to a position beyond the stenosis site. Next, the inner catheter 10 is put on the guide wire from the hand side thereof, the inner catheter 10 is pushed forward using the guide wire as a guide, and the tip portion 14 of the inner catheter 10 is inserted to a position beyond the narrowed portion of the bile duct.

For example, the tube stent 20 is inserted from the duodenum 100 into the papilla 102 of the bile duct 101 and sent to the stenotic site where the bile duct cancer 103 is occurring. The small diameter portion 15 and the small diameter portion 26 of the stent of the inner catheter 10 facilitate the insertion and passage of the stenotic site, so that the operability of the tube stent delivery system 1 is improved. The duodenum 100 and the bile duct 101 are substantially orthogonal to each other, but since the tube stent 20 and the inner catheter 10 are in close contact with each other, the tube stent 20 and the inner catheter 10 do not separate from each other, and the tube stent can be smoothly reached to the target site. 20 can be transported.

When the tube stent 20 is placed at the target site and the biliary drainage can be performed, the inner catheter 10 is pulled out, and the outer catheter 30 stops the movement of the tube stent 20. As a result, the tube stent 20 and the inner catheter 10 are smoothly separated, and the tube stent 20 is placed at the target site.

Further, as shown in FIG. 10, an dilated stent (metallic stent, reticulated stent) 60 may be used in order to open the stenotic site to a predetermined size in advance. In this case, the expansion stent 60 has a mesh shape, and it is difficult to insert the expansion stent 60 with the outer diameter of the conventional inner catheter tube wall portion. However, since the inner catheter 10 of the present embodiment has a small diameter portion 15, it is easy. Can be inserted into. The dilated stent 60 dilates the stenotic site of the hilar bile duct 112 where the left hepatic duct 110 and the right hepatic duct 111 are separated, and the tip 14 of the inner catheter 10 inserts the mesh pattern of the dilated stent 60 to the right. It can easily advance into the hepatic duct 111, and the distal end side of the tube stent 20 can easily follow. In particular, when the tube stent 20 is provided with the small diameter portion 26 of the stent, such fine movements become easier, smooth passage through the expansion stent 60 (stent instent) becomes possible, and better medical practice is realized. can.
(Embodiment 2)

The present invention is not limited to the above-described first embodiment. For example, a tube stent delivery system may be constructed using an inner catheter having a tapered small diameter portion.

By configuring the tube stent delivery system in this way, the operability during in-vivo movement is improved, and in particular, the force and torque for inserting and passing the stenotic site are further reduced.
(Embodiment 3)

In the first embodiment, the tube stent delivery system is configured so that the portion where the formation of the small diameter portion of the inner catheter is started is closer to the tip side (closer to the tip side) than the vicinity of the center of the tube stent. Not limited.

For example, the portion where the formation of the small diameter portion of the inner catheter is started is arranged outside the tube stent (so that the small diameter portion of the inner catheter is arranged on the distal end side of the distal end portion of the tube stent, that is, A tube stent delivery system may be configured (so that the small diameter portion of the inner catheter projects from the tip of the tube stent).
(Other embodiments)

For example, a tube stent delivery system is configured such that a small diameter portion having an outer diameter smaller than that of other portions is provided on the distal end side of the inner catheter, and at least a part of the small diameter portion is surrounded by the tube stent. May be good.

By configuring the tube stent delivery system in this way, it is possible to suppress the displacement of the small diameter portion, ensure stable movement in the body, and easily pass the internal tube deformed at various angles. , The operability can be improved. In addition, it can easily pass through a reticulated stent (expansion stent) and is suitable for various drainage applications. Then, the force of insertion in the narrowed portion is reduced, and the passage operability of the narrowed portion becomes easy.

The present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, and the like. In addition, the material, shape, size, numerical value, form, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

The tube stent delivery system of the present invention is ideal for fields where it is desired that the tube stent does not inadvertently disengage from the middle catheter during in-vivo movement.

1 Tube Stent Delivery System 10 Inner Catheter 11 Inner Catheter Tube Wall 12 Inner Catheter Insertion 13 Inner Catheter Opening 14 Tip 15 Small Diameter 20 Tube Stent 21 Stent Tube Wall 22 Stent Insertion 23 Flap 24 Stent Opening 25 Joint part 26 Stent small diameter part 30 Outer catheter 31 Outer catheter tube wall part 32 Outer catheter insertion part 33 Outer catheter opening 40 Middle catheter 41 Middle catheter tube wall part 42 Middle catheter insertion part 43 Middle catheter opening 50 Operation part 60 Expansion stent D1 Inner catheter outer diameter D2 Small diameter outer diameter F1 Tube stent outer diameter F2 Stent small diameter outer diameter L Joint inner diameter M Middle catheter outer diameter

Claims (6)

With the inner catheter
The middle catheter into which the inner catheter is inserted and the middle catheter
The outer catheter into which the middle catheter is inserted and the outer catheter
A tube stent in which the distal end side of the inner catheter is inserted and has a joint to be joined to the middle catheter.
It is a tube stent delivery system equipped with
The total length of the middle catheter is longer than the total length of the outer catheter.
When the middle catheter is inserted over the entire length of the outer catheter, a part of the distal end side of the middle catheter protrudes from the distal end side of the outer catheter.
When a part of the distal end side of the middle catheter is inserted into the tube stent, the distal end of the tube stent and the distal end of the outer catheter come into contact with or come into close contact with each other.
The inner diameter of the joint is smaller than the outer diameter of the middle catheter.
Tube stent delivery system. With the inner catheter
The middle catheter into which the inner catheter is inserted and the middle catheter
The outer catheter into which the middle catheter is inserted and the outer catheter
A tube stent in which the distal end side of the inner catheter is inserted and has a joint to be joined to the middle catheter.
It is a tube stent delivery system equipped with
The middle catheter is attached to the outer catheter so that a part of the distal end side protrudes from the outer catheter and cannot be separated.
When a part of the distal end side of the middle catheter is inserted into the tube stent, the distal end of the tube stent and the distal end of the outer catheter come into contact with or come into close contact with each other.
The inner diameter of the joint is smaller than the outer diameter of the middle catheter.
Tube stent delivery system. A small diameter portion having a small outer diameter of the inner catheter is provided on the distal end side of the inner catheter.
The tube stent delivery system according to claim 1 or 2. The outer diameter of the small diameter portion becomes smaller toward the tip end portion of the inner catheter.
The tube stent delivery system according to claim 3. The small diameter portion is characterized in that it has a tapered shape.
The tube stent delivery system according to claim 3. At least a part of the small diameter portion is surrounded by the tube stent.
The tube stent delivery system according to any one of claims 3 to 5.

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