CN114849025A

CN114849025A - Balloon catheter and catheter system

Info

Publication number: CN114849025A
Application number: CN202110983697.9A
Authority: CN
Inventors: 早川浩一
Original assignee: Terumo Corp
Current assignee: Terumo Corp
Priority date: 2021-02-04
Filing date: 2021-08-25
Publication date: 2022-08-05
Also published as: JP2022119396A

Abstract

The invention provides a balloon catheter and a catheter system, which can restrain the twist of a balloon and enable the balloon to smoothly protrude from the front end opening of an outer tube. A balloon catheter (12) forming a catheter system (10) is provided with an outer tube (24). A recess (40) extending in the axial direction of the outer tube (24) is formed on the front end side of the inner peripheral surface of the outer tube (24). A rotation restricting section (23) is fixed to the outer peripheral surface of the inner tube (62), and the rotation restricting section (23) has a stopper section (82) that is inserted into the recess (40) so as to be movable in the distal direction relative to the outer tube (24).

Description

Balloon catheter and catheter system

Technical Field

The present invention relates to a balloon catheter and a catheter system.

Background

For example, patent document 1 discloses a catheter system including a balloon catheter and a oviduct scope (endoscope) for treating a diseased portion (a stricture portion or an occlusion portion) of a fallopian tube. The balloon catheter comprises: an outer tube having flexibility; an inner tube disposed in an inner cavity of the outer tube so as to be movable in an axial direction relative to the outer tube; and a tubular balloon that connects the distal end portion of the outer tube and the distal end portion of the inner tube to each other and expands radially inward of the outer tube.

In the oviduct forming operation under the oviduct scope, in a state that a balloon in an inflated state is supported by a linear insertion part of the oviduct scope, a pushing force in a front end direction is transmitted from an inner tube to the balloon, and the balloon is inserted into an oviduct orifice in a mode of protruding from a front end opening of an outer tube while being turned over at a front end part of the balloon.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 3921108

Disclosure of Invention

Problems to be solved by the invention

However, when an insertion force is applied from the inner tube to the balloon, the inner tube may rotate in the circumferential direction with respect to the outer tube, and the balloon may twist. This may prevent the balloon from smoothly protruding from the distal end opening of the outer tube.

The present invention has been made in view of the above problems, and an object thereof is to provide a balloon catheter and a catheter system capable of suppressing twisting of a balloon and smoothly projecting the balloon from a distal end opening of an outer tube.

Means for solving the problems

One aspect of the present invention is a balloon catheter having: an outer tube having flexibility; an inner tube disposed in an inner cavity of the outer tube so as to be movable in an axial direction relative to the outer tube; and a tubular balloon that connects a distal end portion of the outer tube and a distal end portion of the inner tube to each other and inflates radially inward of the outer tube, wherein in the balloon catheter, in a state where the balloon in an inflated state is supported by a linear insertion portion of a medical device, a pushing-in force in a distal end direction is transmitted from the inner tube to the balloon, and the balloon protrudes in the distal end direction from a distal end opening of the outer tube while being turned over at the distal end portion thereof, a recessed portion extending in the axial direction is formed on a distal end side of an inner peripheral surface of the outer tube, and a rotation restricting portion having a stopper portion inserted into the recessed portion so as to be movable in the distal end direction with respect to the outer tube is fixed to an outer peripheral surface of the inner tube.

Another aspect of the present invention is a catheter system including the balloon catheter described above and the medical device.

Effects of the invention

According to the present invention, the stopper of the rotation restricting portion is inserted into the recess of the outer tube. Thus, even when a rotational force acts in the circumferential direction of the inner pipe when the inner pipe is pushed in the distal direction, the stopper portion contacts the wall surface in which the recess is formed, and therefore, the inner pipe can be prevented from rotating in the circumferential direction with respect to the outer pipe. Further, when the pushing force is transmitted from the inner tube to the balloon, the stopper slides in the recessed portion in the distal end direction, so that the balloon can be smoothly projected from the distal end opening of the outer tube.

Drawings

Fig. 1 is a schematic configuration diagram of a balloon catheter system including an embodiment of the present invention.

Fig. 2 is a partially omitted longitudinal cross-sectional view of the catheter system of fig. 1.

Fig. 3A is a cross-sectional view taken along line IIIA-IIIA of fig. 2, and fig. 3B is a cross-sectional view taken along line IIIB-IIIB of fig. 2.

Fig. 4 is a partially omitted top view of the tubular member of fig. 2.

FIG. 5 is a 1 st illustration of a sub-salpingoplasty using the catheter system of FIG. 1.

FIG. 6 is a 2 nd illustration of the sub-salpingoplasty.

FIG. 7 is a 3 rd illustration of the sub-salpingoplasty.

FIG. 8 is a 4 th illustration of the sub-salpingoplasty.

FIG. 9 is a 5 th illustration of the sub-salpingoplasty.

FIG. 10 is a 6 th illustration of the sub-salpingoplasty.

Fig. 11 is a cross-sectional explanatory view of a balloon catheter according to a modification.

Fig. 12 is a cross-sectional view taken along line XII-XII of fig. 11.

Description of the reference numerals

10

… catheter system

12, 12A … balloon catheter

14 … endoscope (medical device) 22 … balloon

23 …

rotation restricting parts

24, 24a … outer tube

30. 30a … outer tube body 33 … tubular member

34 … recess of No. 1

inner cavity

40, 40a …

42 … tubular front end 44 … tubular base end

54 … front end opening 62 … inner tube

82 … stop 90 … insert

Space outside Sc …

Detailed Description

Hereinafter, a balloon catheter and a catheter system according to the present invention will be described with reference to the accompanying drawings by referring to preferred embodiments.

As shown in fig. 1, a catheter system 10 of an embodiment of the present invention includes a balloon catheter 12 and an endoscope 14 (a salpingoscope) as a medical device. As shown in fig. 5 to 10, the catheter system 10 is used, for example, in a sub-salpingography fallopian tube formation operation for treating a lesion 204 (a stenosis portion, an occlusion portion, or the like) of a fallopian tube 202. In addition to the fallopian tube 202, the catheter system 10 can be used for treating a lesion in a living body tube such as a blood vessel, a bile duct, a trachea, an esophagus, a urethra, a large intestine, or other organs.

In the following description of the catheter system 10, the left side (arrow X1 direction) in fig. 1 is referred to as the "tip end", and the right side (arrow X2 direction) in fig. 1 is referred to as the "base end".

As shown in fig. 1 and 2, the balloon catheter 12 includes an outer catheter 16, a slider 18 provided on the outer catheter 16, an inner catheter 20 inserted into the outer catheter 16, a balloon 22, and a rotation restricting portion 23.

The outer pipe 16 has: an elongated outer tube 24 having flexibility; an outer tube hub 26 (outer tube operating portion) provided at a base end portion of the outer tube 24; and a set screw 28 provided to the outer tube hub 26. The entire length of the outer tube 24 is preferably set to 100mm to 1500mm, and more preferably 200mm to 1000 mm.

In fig. 2, the outer tube 24 comprises: an outer tube body 30; a front end member 32 (front end contact) provided at the front end portion of the outer tube main body 30; and a tubular member 33 disposed in the 1 st lumen 34 of the outer tube body 30. Examples of the constituent material of each of the outer tube main body 30, the distal end member 32, and the tubular member 33 include polyolefins (e.g., polyethylene, polypropylene, polybutylene, etc.), polyesters (e.g., polyethylene terephthalate, etc.), elastomer resins (e.g., polyolefin elastomers, polyester elastomers, polyamide elastomers, fluororesin elastomers, polyurethane elastomers, etc.), polymer materials having flexibility (e.g., polytetrafluoroethylene, polyimide, ethylene-vinyl acetate copolymers, silicone rubber, etc.), soft polyvinyl chloride, polyurethane, polyamide, and the like. The outer tube main body 30 and the tubular member 33 may be made of the same material or different materials.

The cross section of the 1 st lumen 34 of the outer tube main body 30, which penetrates from the distal end to the proximal end, is formed in a circular shape (see fig. 3A and 3B). The distal end of the outer tube main body 30 is formed in an arc shape curved in the axial direction. The outer tube body 30 has a substantially constant outer diameter and inner diameter over its entire length.

The outer side of the distal member 32 is curved to prevent damage to the balloon catheter 12 and the living tissue. A balloon outlet 52 is formed in the distal end member 32, and the balloon outlet 52 is used to discharge the balloon 22 in a distal end direction (direction of arrow X1) with respect to the distal end member 32. The balloon lead-out hole 52 communicates with a front end opening 54 of the outer tube 24.

The tubular member 33 is formed in a circular tubular shape and extends over the entire length of the outer tube main body 30. On the inner peripheral surface of the tubular member 33 (inner peripheral surface of the outer tube 24), 1 recessed portion 40 extending in the axial direction (arrow X direction) of the tubular member 33 is formed. The recess 40 is a slit 41 (see fig. 2 and 4) that penetrates the wall of the tubular member 33 in the radial direction. The front end of the slit 41 is located in the middle of the tubular member 33. The base end of the slit 41 is located at the base end of the tubular member 33. That is, the tubular member 33 includes a tubular distal end portion 42 positioned at the distal end of the slit 41 and a tubular proximal end portion 44 in which the slit 41 is positioned.

The tubular tip portion 42 is formed in an annular shape in cross section (see fig. 3A). The tubular base end portion 44 is formed in a C-shape (see fig. 3B). The length L1 in the axial direction of the tubular tip portion 42 is shorter than the length L2 in the axial direction of the tubular base end portion 44. The length L1 of the tubular tip portion 42 is preferably set to, for example, 30mm or more and 80mm or less, more preferably 40mm or more and 70mm or less, and still more preferably 50mm or more and 60mm or less. The length L2 of the tubular base end portion 44 (slit 41) is preferably set to 130mm or more and 300mm or less, for example. As shown in fig. 4, the width D6 of the slit 41 is preferably smaller than the outer diameter of the insertion portion 90 of the endoscope 14, for example, preferably 0.1mm or more and 0.6mm or less, and more preferably 0.2mm or more and 0.5mm or less.

The distal end portion of the tubular distal end portion 42 is fixed (fused or bonded) to the outer tube main body 30 (see fig. 2). In fig. 4, the outer diameter D1 of the tubular tip portion 42 is smaller than the outer diameter D2 of the tubular base end portion 44. The inner diameter D3 of the tubular tip portion 42 is smaller than the inner diameter D4 of the tubular base end portion 44. In the state where the balloon 22 is inflated radially inward of the outer tube 24, both the inner diameter D3 of the tubular distal end portion 42 and the inner diameter D4 of the tubular proximal end portion 44 are set to be smaller than 3 times the outer diameter D5 (see fig. 6) of the portion of the balloon 22 that is in close contact with the outer peripheral surface of the insertion portion 90 of the endoscope 14. The wall thickness of the tubular tip portion 42 is substantially the same as the wall thickness of the tubular base end portion 44. That is, a step portion 45 is provided at a boundary portion between the tubular leading end portion 42 and the tubular base end portion 44.

As shown in fig. 2 and 3A, the outer peripheral surface of the tubular tip portion 42 is separated from the inner peripheral surface of the outer tube main body 30. In other words, an annular space 46 is formed between the outer peripheral surface of the tubular tip portion 42 and the inner peripheral surface of the outer tube main body 30.

In fig. 2, a proximal end portion of the tubular proximal end portion 44 is fixed (fused or bonded) to the outer tube main body 30. The outer peripheral surface of the tubular base end portion 44 is in contact with or close to the outer peripheral surface of the outer tube main body 30.

As shown in fig. 1 and 2, the outer tube hub 26 is made of hard resin or metal (stainless steel, titanium alloy, or the like). Examples of the hard resin include polycarbonate, acrylic resin, polyester, polyolefin, styrene resin, polyamide, polysulfone, polyarylate, and polyetherimide.

In fig. 2, the outer tube hub 26 is formed in a hollow shape having a size that is easy to handle manually. The outer tube hub 26 is provided with a 1 st space 53 communicating with the 1 st lumen 34 of the outer tube 24, a 1 st insertion hole 55 located on the base end side of the 1 st space 53 and through which the inner catheter 20 is inserted, and a 1 st introduction port 56 for introducing the balloon inflation fluid into the 1 st space 53. The balloon inflation fluid is used to inflate the balloon 22 shown in fig. 2 radially inward of the outer tube 24. The balloon inflation fluid is, for example, saline. The outer tube hub 26 is provided with a 1 st seal member 57, and the 1 st seal member 57 prevents the balloon inflation fluid in the 1 st space 53 from leaking to the outside through the 1 st insertion hole 55.

Set screws 28 are used to secure the inner catheter 20 to the outer hub 26. The material of the fixing screw 28 can be the same as the material of the outer tube hub 26.

The slider 18 is provided in a state of being movable (slidable) in the axial direction of the outer tube 24 with respect to the outer peripheral surface of the outer tube main body 30. The overall length of the slide 18 is shorter than the overall length of the outer tube 24. The slider 18 has an elongated tubular slider body 58 and a slider hub 60 (slider operating portion) provided at a base end portion of the slider body 58. The slider body 58 and the slider hub 60 are each made of the same material as the outer tube hub 26 described above. The slider hub 60 is formed in a ring shape of a size that is easy to handle manually.

In a state where the slider 18 is moved to the closest position to the base end side (in the direction of the arrow X2) with respect to the outer tube main body 30 (a state where the base end of the slider 18 is positioned at the distal end of the outer tube hub 26), the distal end side of the outer tube main body 30 is exposed to the distal end side of the slider 18 and is bent in an arc shape. In a state where the slider 18 is moved to the closest position to the tip end side (the direction of arrow X1) with respect to the outer tube main body 30, the tip end side of the outer tube main body 30 linearly extends along the shape of the slider main body 58.

As shown in fig. 1 and 2, the inner catheter 20 includes an elongated inner tube 62 and an inner tube hub 64 (inner tube operating portion) provided at a proximal end portion of the inner tube 62. The entire length of the inner tube 62 is preferably set to 100mm to 1500mm, and more preferably 200mm to 1000 mm.

In fig. 2, as a material constituting the inner tube 62, a relatively hard resin (for example, a fluororesin, a polycarbonate, a polyimide, a PEEK resin, etc.) or a metal (for example, stainless steel, titanium, a titanium alloy, etc.) can be exemplified. The inner tube 62 is formed with a 2 nd lumen 66 penetrating from the distal end to the proximal end.

The inner tube 62 is inserted through the outer tube hub 26 and disposed within the No. 1 inner cavity 34 of the outer tube body 30. The front end of the inner tube 62 is located in the base end direction (arrow X2 direction) relative to the front end of the outer tube main body 30. An outer lumen Sa (an expansion lumen) through which a balloon expansion fluid flows is provided between the outer peripheral surface of the inner tube 62 and the inner peripheral surface of the tubular member 33.

An elongated insertion portion 90 of the endoscope 14, which also functions as a balloon support device, is inserted into the No. 2 lumen 66 of the inner tube 62. In a state where the insertion portion 90 is inserted into the 2 nd lumen 66 of the inner tube 62, an inner lumen Sb (perfusion lumen) through which a perfusion fluid flows is formed between the inner tube 62 and the insertion portion 90. The perfusion fluid is, for example, physiological saline.

The inner tube hub 64 is constructed of the same material as the outer tube hub 26. The inner tube hub 64 is formed in a hollow shape. The inner tube hub 64 is provided with: a 2 nd space 68 communicating with the 2 nd lumen 66 of the inner tube 62; a 2 nd insertion hole 70 which is located on the proximal end side of the 2 nd space 68 and through which the insertion portion 90 of the endoscope 14 is inserted; and a 2 nd introduction port 72 for introducing the perfusion liquid into the 2 nd space 68. The inner tube hub 64 is provided with a 2 nd sealing member 73, and the 2 nd sealing member 73 prevents the perfusion fluid in the 2 nd space 68 from leaking to the outside through the 2 nd insertion hole 70.

The balloon 22 is a tubular member that connects the distal end portion of the outer tube 24 and the distal end portion of the inner tube 62 to each other. The balloon 22 is inflated radially inward of the outer tube 24 by the balloon inflation fluid. In other words, the balloon 22 is formed to be elastically deformable in the radial direction.

The material constituting the balloon 22 is preferably composed of polyolefin (for example, polyethylene, polypropylene, polybutylene, etc.), polyester (polyethylene terephthalate, etc.), elastomer resin (polyolefin elastomer, polyester elastomer, polyamide elastomer, fluororesin elastomer, polyurethane elastomer, etc.), polymer material having flexibility (natural rubber, ethylene-propylene copolymer, polytetrafluoroethylene, polyimide, ethylene-vinyl acetate copolymer, silicone rubber, etc.), soft polyvinyl chloride, polyurethane, polyamide, polyisoprene, polyester, etc.

One end of the balloon 22 is bonded or fused to the distal end of the outer tube 24 (the proximal end of the distal end member 32). In other words, one end portion of the balloon 22 is bonded or fused to the outer tube 24 in the vicinity of the proximal end side of the balloon lead-out hole 52. Specifically, one end portion of the balloon 22 is clamped between the front end of the outer tube main body 30 and the front end member 32. The other end portion of the balloon 22 is bonded or fused to the distal end portion of the outer peripheral surface of the inner tube 62.

The other end of the balloon 22 is fixed to the distal end of the inner tube 62 by a balloon fixing member 74. The other end of the balloon 22 may be bonded or fused to the distal end of the inner peripheral surface of the inner tube 62. The balloon 22 has a lumen 76 into which an insertion portion 90 of the endoscope 14 can be inserted. A bag-shaped outer space Sc having a closed distal end is formed between the outer peripheral surface of the balloon 22 and the inner peripheral surface of the tubular member 33. The balloon fixing member 74 is formed in an annular shape. The balloon fixing member 74 is disposed in the lumen of the tubular member 33.

As shown in fig. 6 and 7, the pushing force (pushing force in the distal direction) is transmitted from the inner tube 62 to the balloon 22, and the balloon 22 protrudes in the distal direction from the distal opening 54 of the outer tube 24 while being curled at the distal end portion 22a thereof. At this time, the balloon 22 is formed with a portion folded into two layers in the radial direction at the protruding portion 22b protruding in the arrow X1 direction from the distal end opening 54 of the outer tube 24.

As shown in fig. 2 and 3B, the rotation restricting portion 23 is provided at the distal end portion of the inner tube 62, and restricts the rotation of the inner tube 62 in the circumferential direction with respect to the outer tube 24. In fig. 3B, the rotation restricting portion 23 has an annular portion 80 and 1 stopper portion 82 (convex portion) protruding radially outward from the outer peripheral surface of the annular portion 80.

The inner peripheral surface of the annular portion 80 is fixed (fused or bonded) to the outer peripheral surface of the inner pipe 62. That is, the inner tube 62 is inserted in the inner cavity of the circular portion 80. The circular ring portion 80 is disposed in the lumen of the tubular member 33. The stopper 82 protrudes radially outward from the outer peripheral surface of the annular portion 80. The stopper 82 is disposed in the slit 41 of the tubular member 33. The stopper 82 is slidable in the slit 41 along the axial direction (arrow X direction). The protruding ends of the stopper portions 82 contact or approach the inner peripheral surface of the outer tube main body 30. The stopper 82 extends along the arrow X direction over the entire length of the annular ring 80. The stopper 82 has an arcuate outer peripheral surface in cross section.

As shown in fig. 2, the endoscope 14 is a fallopian tube scope for observing the fallopian tube 202 (see fig. 5). The endoscope 14 has a flexible linear insertion portion 90, and the insertion portion 90 is inserted into the No. 2 lumen 66 of the inner tube 62 of the balloon catheter 12 and the lumen 76 of the balloon 22. The insertion portion 90 is formed of, for example, a resin material. Although not shown in detail, the insertion portion 90 includes a covering member, a light emitting unit that emits light, and an imaging unit that images the fallopian tube 202. The light emitting unit includes an elongated optical waveguide (optical fiber). The image pickup unit includes a lens unit and an electrical unit (e.g., an optical fiber or the like) for transmitting an image imaged by the lens unit.

Next, a description is given of a sub-salpingography using the catheter system 10 configured as above.

In a sub-salpingoplasty, the above-described catheter system 10 is prepared in a preparation process. Then, the user fixes the inner tube 62 in a state of being completely pulled to the proximal end side (the direction of arrow X2) using the fixing screw 28 in advance. Further, the slider 18 is slid in the distal end direction of the outer tube 24 with respect to the outer tube 24, whereby the distal end side of the outer tube main body 30 is straightened.

Next, in the insertion step, the user inserts the balloon catheter 12 into the uterine fundus 200 through the cervical canal (see fig. 5). Then, in the sliding process, the slider 18 is pulled back toward the base end of the outer tube 24 with respect to the outer tube 24. Thereby, as shown in fig. 5, the distal end side of the outer tube main body 30 is exposed from the slider 18 and is bent. At this time, the user positions the distal end portion of the insertion portion 90 of the endoscope 14 at the distal end opening 54 of the outer tube 24, and confirms the oviduct port 202a from the captured image of the endoscope 14.

Then, the user returns the insertion portion 90 of the endoscope 14 to the initial position (the position shown in fig. 5), and then performs the balloon derivation step. Specifically, in the balloon lead-out step, as shown in fig. 6, the balloon inflation fluid is supplied to the 1 st introduction port portion 56 (pressurizing step). Thereby, the balloon inflation fluid is supplied from the 1 st introduction port portion 56 to the outer space Sc of the balloon 22 through the outer lumen Sa. Therefore, the balloon 22 is pressed radially inward by the balloon-expanding fluid supplied to the outer space Sc and is elastically deformed. That is, a portion of the balloon 22 located on the outer peripheral side of the insertion portion 90 is in close contact with the outer peripheral surface of the insertion portion 90. Inner surfaces of portions of the balloon 22 located on the front end side than the front end of the insertion portion 90 contact each other.

Thereafter, the user operates the inner tube hub 64 with the set screw 28 loosened, and advances the inner tube 62 relative to the outer tube 24 (advancing process). As a result, as shown in fig. 7, the stopper 82 of the rotation restricting portion 23 slides in the distal direction in the slit 41 of the tubular member 33, and the balloon 22 pressed in the distal direction by the inner tube 62 advances relative to the outer tube 24 together with the insertion portion 90. That is, the pushing force is transmitted from the inner tube 62 to the balloon 22, and the balloon 22 projects from the front end opening 54 of the outer tube 24 in the front end direction (the arrow X1 direction) together with the insertion portion 90.

In the advancing step, one end portion of the balloon 22 is fixed to the distal end portion of the outer tube 24, and therefore the balloon 22 advances while turning the distal end portion 22a (projecting end portion) thereof. That is, the balloon 22 is turned over at its front end portion 22a (projecting end portion) so that the inner surface faces outward. Therefore, the advancement distance of the balloon 22 is half of the advancement distance of the insertion portion 90.

In the advancing step, the stopper 82 of the rotation restricting portion 23 slides in the slit 41 of the tubular member 33 in the distal direction. Therefore, in the advancing step, even when a rotational force in the circumferential direction acts on the inner tube 62, the stopper 82 is brought into contact with the wall surface in which the slit 41 is formed, whereby the inner tube 62 can be prevented from rotating in the circumferential direction with respect to the outer tube 24. Therefore, the balloon 22 can be suppressed from twisting in the circumferential direction of the inner tube 62. Therefore, the balloon 22 smoothly protrudes from the front end opening 54 of the outer tube 24 in the front end direction.

Next, the user determines whether the balloon 22 has reached the lesion 204 based on the captured image of the endoscope 14. When the balloon 22 is positioned in front of the lesion 204, the perfusion liquid (perfusion fluid) is supplied to the 2 nd introduction port portion 72 while the balloon inflation fluid is depressurized (depressurization step). Thus, the perfusion liquid flows between the balloon 22 and the insertion portion 90 of the endoscope 14 through the inner lumen Sb. Next, as shown in fig. 8, the user retracts the endoscope 14 by a predetermined distance (retraction step). Thereafter, the above-described pressing step and advancing step are performed again.

As shown in fig. 9, in the advancing step, when the distal end portion 22a of the balloon 22 comes into contact with the lesion 204, a large axial compressive force acts on the balloon 22 when the user pushes the inner tube 62 in the distal direction. Such a compressive force is likely to increase when the lesion 204 is completely occluded. When a large compression force acts on the balloon 22, the balloon 22 and the insertion portion 90 deform in a direction intersecting the axial direction, and are easily deformed by buckling.

However, since the tubular member 33 is provided in the 1 st lumen 34 of the outer tube main body 30, the outer peripheral surface of the balloon 22 contacts the inner peripheral surface of the tubular member 33 before the balloon 22 and the insertion portion 90 are largely deformed in the direction intersecting the axial direction. Therefore, the buckling deformation of the insertion portion 90 can be suppressed.

Thereafter, as shown in fig. 10, when the balloon 22 completely passes through the lesion 204, the lesion 204 is expanded by the balloon 22. That is, the stenosis or occlusion of the fallopian tube 202 is improved.

After opening the lesion 204, the user decompresses the balloon-inflating fluid and then pulls out the balloon catheter 12 and the endoscope 14 (pulling-out step). Before the balloon catheter 12 is pulled out, the endoscope 14 is positioned at the distal end portion of the balloon 22 by pulling the inner tube 62 to retract the balloon 22 while injecting the perfusion fluid through the 2 nd introduction port portion 72, and the balloon catheter 12 may be pulled out while observing the inside of the fallopian tube 202 at the time of the pulling-out step. Thereby, the sub-salpingoplasty is ended.

The present embodiment has the following effects.

According to the balloon catheter 12, the stopper 82 of the rotation restricting portion 23 is inserted into the recess 40 of the outer tube 24. Thus, even when a rotational force acts in the circumferential direction of the inner tube 62 when the inner tube 62 is pushed in the distal direction, the stopper 82 contacts the wall surface on which the recess 40 is formed, and thereby the inner tube 62 can be prevented from rotating in the circumferential direction with respect to the outer tube 24. When the pushing-in force is transmitted from the inner tube 62 to the balloon 22, the stopper 82 slides in the distal direction in the recess 40, so that the balloon 22 can be smoothly projected from the distal opening 54 of the outer tube 24.

The outer tube 24 includes an outer tube body 30 extending in the axial direction and a tubular member 33 disposed in the 1 st lumen 34 of the outer tube body 30. The tubular member 33 is formed with a recess 40.

According to such a configuration, since the tubular member 33 is disposed in the inner cavity of the outer tube main body 30, the distance between the outer peripheral surface of the balloon 22 and the inner peripheral surface of the outer tube 24 can be reduced as compared with the case where the tubular member 33 is not provided. Thus, in the case where a large axial compressive force acts on the balloon 22 in the case of a disease example in which the lesion 204 is completely occluded, the outer peripheral surface of the balloon 22 can be brought into contact with the inner peripheral surface of the tubular member 33 before the balloon 22 and the insertion portion 90 are largely deformed in the direction intersecting the axial direction, and therefore buckling deformation of the insertion portion 90 can be suppressed.

The recess 40 is a slit 41 that penetrates the wall of the tubular member 33 in the radial direction.

With this configuration, the tubular member 33 having the slit 41 can easily provide the recessed portion 40 on the inner peripheral surface of the outer tube 24.

The tip of the slit 41 is located at a halfway position in the axial direction of the tubular member 33, and the base end of the slit 41 is located at the base end of the tubular member 33.

With such a configuration, the rigidity of the tubular tip portion 42 can be improved as compared with the case where the slit 41 is formed over the entire length of the tubular member 33.

The rotation restricting portion 23 is provided at the front end portion of the inner tube 62. In the initial state of the balloon catheter 12 in which the balloon 22 does not protrude from the distal end opening 54, the distal end of the slit 41 is positioned in the distal end direction than the proximal end of the balloon 22.

With such a configuration, the length of the outer tube 24 can be reduced compared to a case where the distal end of the slit 41 is located closer to the proximal end side than the proximal end of the balloon 22 in the initial state of the balloon catheter 12.

The distal end of the tubular member 33 is fixed to the distal end of the outer tube main body 30.

With this configuration, the tubular member 33 can be prevented from being displaced in the proximal direction (the direction of arrow X2) with respect to the outer tube 24.

The inner diameter D3 of the tubular leading end portion 42 of the tubular member 33 on the leading end side of the slit 41 is smaller than the inner diameter D4 of the tubular base end portion 44 of the tubular member 33 provided with the slit 41.

With such a configuration, the buckling deformation of the insertion portion 90 at the tubular distal end portion 42 can be effectively suppressed. Further, the rotation restricting portion 23 can be disposed in the inner cavity of the tubular member 33 (tubular base end portion 44) while avoiding an excessively small outer diameter.

The number of the recesses 40 and the stoppers 82 is 1.

With this configuration, the tubular member 33 and the rotation restricting portion 23 can be simplified in configuration.

Next, a balloon catheter 12A according to a modification will be described with reference to fig. 11 and 12. In the balloon catheter 12A of the modification, the same components as those of the balloon catheter 12 are denoted by the same reference numerals, and the description thereof is omitted.

As shown in fig. 11 and 12, the balloon catheter 12A includes an outer catheter 16a, an inner catheter 20, a balloon 22, and a rotation restricting portion 23. The outer catheter 16a has an outer tube hub 26 and an elongated outer tube 24a having flexibility. The outer tube 24a includes an outer tube body 30a and a front end member 32. The outer tube main body 30a is made of the same material as that of the outer tube main body 30. The inner diameter of the outer tube main body 30a is set to be smaller than 3 times the outer diameter D5 (see fig. 6) of the portion of the balloon 22 in close contact with the outer peripheral surface of the insertion portion 90 in a state where the balloon 22 is inflated radially inward of the outer tube 24.

The inner peripheral surface of the outer tube main body 30a is formed with 1 recess 40a extending in the axial direction of the outer tube main body 30 a. The size and shape of the recess 40a are set to be the same as those of the slit 41 described above. The stopper 82 of the rotation restricting portion 23 is inserted into the recess 40a so as to be movable in the front end direction. Such a recess 40a has the same effect as the recess 40 (slit 41) described above.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

The above embodiments are summarized as follows.

The above embodiment discloses a balloon catheter having: an outer tube (24, 24a) having flexibility; an inner tube (62) disposed in an inner cavity (34) of the outer tube so as to be movable in an axial direction relative to the outer tube; and a tubular balloon (22) which connects the front end portion of the outer tube and the front end portion of the inner tube to each other and which is inflated radially inward of the outer tube, in the balloon catheters (12, 12A), the pushing force towards the front end direction is transmitted from the inner tube to the balloon under the state that the inflated balloon is supported by the linear insertion part (90) of the medical device (14), whereby the balloon protrudes in the distal direction from a distal opening (54) of the outer tube while being turned over at the distal end portion thereof, a recess (40, 40a) extending in the axial direction is formed at the front end side of the inner peripheral surface of the outer pipe, a rotation restricting portion (23) is fixed to the outer peripheral surface of the inner pipe, the rotation restricting portion (23) has a stopper portion (82) inserted into the recess so as to be movable in the distal end direction with respect to the outer tube.

In the balloon catheter described above, the outer tube may include: an outer tube body (30) extending in the axial direction; and a tubular member (33) disposed in the lumen of the outer tube body, the tubular member having the recess formed thereon.

In the balloon catheter described above, the recess may be a slit (41) that penetrates the wall of the tubular member in the radial direction.

In the balloon catheter described above, a distal end of the slit may be located at a halfway position in the axial direction of the tubular member, and a proximal end of the slit may be located at a proximal end of the tubular member.

In the above-described balloon catheter, the rotation restricting portion may be provided at a distal end portion of the inner tube, and a distal end of the slit may be positioned in the distal end direction with respect to a proximal end of the balloon in an initial state of the balloon catheter in which the balloon does not protrude from the distal end opening.

In the balloon catheter described above, a distal end portion of the tubular member may be fixed to a distal end portion of the outer tube main body.

In the balloon catheter, an inner diameter (D3) of a tubular distal end portion (42) of the tubular member, which is located on the distal end side of the slit, may be smaller than an inner diameter (D4) of a tubular proximal end portion (44) of the tubular member, which is provided with the slit.

In the above balloon catheter, 1 of the concave portions and the stopper portions may be provided.

The above embodiments disclose a catheter system (10) comprising the above balloon catheter and the medical device.

In the catheter system, the medical device may be an endoscope.

Claims

1. A balloon catheter having: an outer tube having flexibility; an inner tube disposed in an inner cavity of the outer tube so as to be movable in an axial direction relative to the outer tube; and a tubular balloon which connects a distal end portion of the outer tube and a distal end portion of the inner tube to each other and which is inflated radially inward of the outer tube, characterized in that,

in a state where the balloon in an inflated state is supported by a linear insertion portion of a medical device, a pushing force in a distal direction is transmitted from the inner tube to the balloon, and the balloon protrudes in the distal direction from a distal opening of the outer tube while being turned at a distal end portion thereof,

a recess extending in the axial direction is formed on a front end side of an inner peripheral surface of the outer tube,

a rotation restricting portion having a stopper portion inserted into the recess portion so as to be movable in the distal end direction with respect to the outer tube is fixed to an outer peripheral surface of the inner tube.

2. The balloon catheter of claim 1,

the outer tube comprises:

an outer tube body extending in the axial direction; and

a tubular member disposed within the lumen of the outer tube body,

the recess is formed in the tubular member.

3. The balloon catheter of claim 2,

the recess is a slit extending radially through the wall of the tubular member.

4. The balloon catheter of claim 3,

the front end of the slit is located at a halfway position in the axial direction of the tubular member,

the base end of the slit is located at the base end of the tubular member.

5. The balloon catheter of claim 4,

the rotation restricting portion is provided at a front end portion of the inner tube,

in an initial state of the balloon catheter in which the balloon does not protrude from the leading end opening, a leading end of the slit is located in the leading end direction than a base end of the balloon.

6. A balloon catheter according to any one of claims 2-5,

the front end of the tubular member is fixed to the front end of the outer tube main body.

7. A balloon catheter according to any one of claims 3-6,

an inner diameter of a tubular leading end portion of the tubular member located on a leading end side than the slit is smaller than an inner diameter of a tubular base end portion of the tubular member provided with the slit.

8. A balloon catheter according to any one of claims 1-7,

the number of the concave portions and the stopper portions is 1.

9. A catheter system, comprising:

the balloon catheter of any one of claims 1-8; and

the medical device.

10. The catheter system of claim 9,

the medical device is an endoscope.