CN116782844A

CN116782844A - Balloon for balloon catheter

Info

Publication number: CN116782844A
Application number: CN202180088986.0A
Authority: CN
Inventors: 杖田昌人; 小嶋真弘; 中野良纪; 滨渊崇亘
Original assignee: Kaneka Corp
Current assignee: Kaneka Corp
Priority date: 2021-01-21
Filing date: 2021-11-17
Publication date: 2023-09-19
Also published as: WO2022158100A1; JPWO2022158100A1

Abstract

Provided is a balloon capable of improving tracking performance and protecting an expansion portion of the balloon when the balloon in a contracted state is delivered in a body cavity. The balloon (2) for a balloon catheter has a balloon body (27) and an outer protruding portion (60), and satisfies the following (1) and/or (2) in a contracted state of the balloon (2). (1) A first imaginary cylinder C circumscribed by the proximal sleeve part (21) ₁ Radius r of (2) ₁ An imaginary circle C circumscribing the expansion part (20) at the midpoint (20C) of the expansion part (20) ₀ Radius r of (2) ₀ Large. (2) A second imaginary cylinder C circumscribed by the distal sleeve part (22) ₂ Radius r of (2) ₂ An imaginary circle C circumscribing the expansion part (20) at the midpoint (20C) of the expansion part (20) ₀ Radius r of (2) ₀ Large.

Description

Balloon for balloon catheter

Technical Field

The present invention relates to a balloon for a balloon catheter.

Background

Diseases such as angina pectoris and myocardial infarction are caused by the formation of a hardened stenosed portion such as calcification on the inner wall of a blood vessel. As one of their treatments, there is an angiogenesis operation for dilating a stricture using a balloon catheter. The angiogenesis operation is a low invasive therapy that does not require an open chest operation such as bypass operation, and is widely performed.

In the vascular surgery, it is sometimes difficult to dilate a stricture portion hardened by calcification or the like in a general balloon catheter. In addition, a method of dilating a stenosed portion by indwelling an indwelling Stent called Stent In the stenosed portion has been used, but there are cases such as an ISR (In-Stent) lesion In which a neointima of a blood vessel is excessively proliferated and a stenosis of the blood vessel is reproduced after the treatment. In ISR lesions, since the neointima is soft and the surface thereof easily slides, there is a case where a balloon is displaced from a lesion to damage a blood vessel when the balloon is expanded in a general balloon catheter.

As a balloon catheter capable of dilating a stricture even with such calcified lesions and ISR lesions, a balloon catheter provided with a protrusion or a braid for biting into the stricture and a scoring element (scoring element) has been developed. For example, patent document 1 discloses a balloon catheter having a scoring element made of a polymer material having higher rigidity than a polymer material forming a balloon main body, the scoring element being flattened at one end and the other end of the balloon. Patent document 2 discloses a scored balloon structure in which the height of a scored element is reduced along the tapered shape of the balloon, and patent document 3 discloses a balloon catheter in which an outer protruding portion is provided in a straight tube portion of the balloon and an inner protruding portion is provided in a tapered portion. In patent documents 1 to 3, the height of the scoring element is reduced at both end portions of the balloon, or an inner protruding portion is provided instead of an outer protruding portion. In contrast, there is also a balloon catheter that is a high protruding portion having a protruding amount larger than that of a protruding portion disposed in a straight tube portion of the balloon, the protruding portion being disposed in a distal-side tapered portion (patent document 4).

Patent document 1: U.S. patent application publication 2016/0128218 specification

Patent document 2: japanese patent application laid-open No. 2014-506140

Patent document 3: international publication No. 2020/012851 booklet

Patent document 4: international publication No. 2020/0126850 pamphlet

The balloon catheter is inserted into the body cavity in a contracted and folded state and delivered to the treatment site. Accordingly, in the balloon catheters disclosed in patent documents 1 to 3, in order to facilitate insertion into a body cavity, an increase in the outer diameter is suppressed by suppressing the height of the scoring element at the distal end portion of the balloon, and an attempt is made to improve the trafficability of the balloon. However, in such balloon catheter, since the score element height is suppressed at both end portions of the balloon, the expansion portion of the balloon comes into contact with the body cavity wall during delivery of the balloon, and the contact area between the balloon and the body cavity wall during delivery increases. As a result, the traceability of the balloon at the curved portion of the body lumen (the ease of following the curvature of the body lumen by the balloon at the time of balloon delivery in the body lumen) may be reduced. Further, since the balloon is delivered to the lesion by the balloon expansion portion abutting against the body cavity wall, there is a case where the balloon expansion portion expanded to act on the lesion during treatment is damaged during delivery, which may hinder treatment. In the balloon catheter disclosed in patent document 4, the height of the protruding portion disposed on the distal-end side tapered portion is high for the purpose of easily forming an incision in the lesion in the expanded state, but there is room for improvement in the point of improvement in the traceability at the time of delivering the balloon in the contracted state to the lesion and in the protection of the balloon-expanded portion during the delivery.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a balloon for a balloon catheter capable of improving trackability and protecting an expanded portion of the balloon when the balloon in a contracted state is delivered in a body cavity.

One embodiment of a balloon for a balloon catheter according to the present invention, which can solve the above-described problems, is a balloon for a balloon catheter, comprising: an expansion section; a proximal sleeve portion located closer to the proximal side than the expansion portion; and a distal sleeve portion located on a distal side from the expansion portion, wherein the balloon for a balloon catheter includes: a balloon body having an outer surface and an inner surface; and an outer protruding portion protruding radially outward from the outer surface of the balloon body and extending in the longitudinal direction of the balloon body, wherein at least one of the following (1) and (2) is satisfied in the contracted state of the balloon.

(1) First imaginary cylinder C ₁ Radius of (2) is greater than that of imaginary circle C ₀ Is large in radius, the first imaginary cylinder C ₁ Has a central axis parallel to the long axis direction, and the first imaginary cylinder C ₁ Is positioned at the far end and the near end of the near sleeve part, and the near sleeve part is externally connected with the first imaginary cylinder C ₁ At least a part of the side surface of the virtual circle C ₀ The expansion portion is a virtual circle circumscribed in a cross section of a radial direction perpendicular to the longitudinal direction at a midpoint of the longitudinal direction of the expansion portion.

(2) A second imaginary cylinder C ₂ Radius of (2) is greater than that of imaginary circle C ₀ Is large in radius, the second imaginary cylinder C ₂ Has a central axis parallel to the long axis direction, and the second imaginary cylinder C ₂ Is positioned at the far end and the near end of the far sleeve part, and the far sleeve part is externally connected with the second imaginary cylinder C ₂ At least a part of the side surface of the virtual circle C ₀ The expansion portion is a virtual circle circumscribed in a cross section of a radial direction perpendicular to the longitudinal direction at a midpoint of the longitudinal direction of the expansion portion.

Preferably, the expansion portion has a main section from which 10% of the longitudinal direction is removed from each of the distal end and the proximal end, and satisfies at least one of the following (1) and (2) in the contracted state of the balloon,

(1) First imaginary cylinder C ₁ Radius of (C) is greater than that of the third imaginary cylinder C ₃ Is large in radius, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the main section is positioned at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary circleColumn C ₃ At least a portion of the side of (c),

(2) A second imaginary cylinder C ₂ Radius of (C) is greater than that of the third imaginary cylinder C ₃ Is large in radius, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the third imaginary cylinder C is located at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c).

Preferably, the balloon is folded in its contracted state.

Preferably, the outer protruding portion has a distal end portion in a radial cross section, and at least one of the following (1) and (2) is satisfied in a contracted state of the balloon,

(1) The front end part is externally connected with the first imaginary cylinder C at the proximal sleeve part ₁ At least a portion of the side of (c),

(2) The front end part is externally connected with a second imaginary cylinder C at the far side sleeve part ₂ At least a portion of the side of (c).

(1) Only the front end part is externally connected with the first imaginary cylinder C at the proximal sleeve part ₁ At least a portion of the side of (c),

(2) Only the front end part is externally connected with the second imaginary cylinder C at the far side sleeve part ₂ At least a portion of the side of (c).

Preferably, in the contracted state of the balloon, the expansion portion has a fin circumscribing the imaginary circle C ₀ 。

Preferably, in the contracted state of the balloon, the expansion portion has a fin, and the outer protruding portion is disposed at a position other than the fin.

Preferably satisfying at least one of the following (1) and (2),

(1) The outer protruding portion of the proximal sleeve portion and the outer protruding portion of the expansion portion extend continuously in the long axis direction,

(2) The outer protruding portion of the distal sleeve portion and the outer protruding portion of the expansion portion extend continuously in the longitudinal direction.

Preferably, in the contracted state of the balloon, a first imaginary cylinder C at the proximal sleeve portion ₁ Radius ratio of (2) to imaginary circle C at the expansion part ₀ A second imaginary cylinder C in the distal sleeve part having a large radius ₂ Radius of (2) is greater than that of imaginary circle C ₀ Is small. In this case, the expansion portion preferably has a main section in which 10% of the longitudinal direction is removed from each of the distal end and the proximal end, and the first virtual cylinder C at the proximal sleeve portion in the contracted state of the balloon ₁ Radius of (C) is greater than that of the third imaginary cylinder C ₃ A second imaginary cylinder C at the distal sleeve part having a large radius ₂ Radius of (C) is greater than that of the third imaginary cylinder C ₃ Is small in radius, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the third imaginary cylinder C is located at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c). In this case, it is further preferable that the distal sleeve portion has an inner protruding portion protruding radially inward from the inner surface of the balloon main body and extending in the longitudinal direction.

Preferably, the outer protrusion is composed of the same material as the balloon body.

According to the balloon for a balloon catheter described above, in the contracted state of the balloon, the radius of the imaginary cylinder circumscribed by at least one of the proximal sleeve portion and the distal sleeve portion is larger than the radius of the imaginary circle circumscribed by the central portion of the expansion portion, so that when the balloon in the contracted state is delivered in the body cavity, the trackability of the balloon can be improved, and the expansion portion of the balloon can be protected.

Drawings

Fig. 1 shows a side view of a balloon catheter according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view in the longitudinal direction of the balloon catheter shown in fig. 1 in an expanded state.

Fig. 3 is a plan view of the balloon shown in fig. 2, as seen from the outer protrusion side.

Fig. 4 shows a cross-sectional view of IV-IV of fig. 1.

Fig. 5 shows a side view of the balloon catheter shown in fig. 1 in a contracted state.

Fig. 6 shows a side view illustrating another example of the side view shown in fig. 5.

Fig. 7 shows a cross-sectional view VII-VII of fig. 5.

Fig. 8 shows a cross-sectional view showing another example of the cross-sectional view shown in fig. 7.

Fig. 9 shows a cross-sectional view showing still another example of the cross-sectional view shown in fig. 7.

Fig. 10 shows a cross-sectional view showing still another example of the cross-sectional view shown in fig. 7.

FIG. 11 shows a section view XI-XI of FIG. 5.

Fig. 12 shows a cross-sectional view showing another example of the cross-sectional view shown in fig. 11.

Fig. 13 is a side view of a balloon for a balloon catheter according to another embodiment of the present invention in a contracted state.

Fig. 14 is a radial cross-sectional view of an expanded portion in a folded state of a balloon for a balloon catheter according to an embodiment of the present invention, taken at a midpoint in a longitudinal direction thereof.

Fig. 15 shows a cross-sectional view showing another example of the cross-sectional view shown in fig. 14.

Fig. 16 is a side view of a balloon for a balloon catheter according to still another embodiment of the present invention in a contracted state.

Fig. 17 shows a cross-sectional view of XVII-XVII of fig. 16.

Fig. 18 shows a cross-sectional view showing another example of the cross-sectional view shown in fig. 17.

Fig. 19 is a perspective view of a parison before inflation according to an embodiment of the present invention.

Detailed Description

The present invention will be specifically described below based on embodiments, but the present invention is not limited to the following embodiments, and needless to say, the present invention can be implemented with appropriate modifications within a range that can meet the gist of the present invention described above and below, and these are included in the technical scope of the present invention. In each of the drawings, hatching, component reference numerals, and the like may be omitted for convenience, and in this case, reference is made to the specification and other drawings. In addition, the dimensions of the various components in the drawings are preferred to facilitate an understanding of the features of the present invention, and thus there are cases where they differ from actual dimensions.

The balloon for a balloon catheter according to an embodiment of the present invention includes: an expansion section; a proximal sleeve portion located closer to the proximal side than the expansion portion; and a distal sleeve portion located on a distal side from the expansion portion, wherein the balloon for a balloon catheter includes: a balloon body having an outer surface and an inner surface; and an outer protruding portion protruding radially outward from the outer surface of the balloon body and extending in the longitudinal direction of the balloon body, wherein at least one of the following (1) and (2) is satisfied in the contracted state of the balloon.

(2) A second imaginary cylinder C ₂ Radius of (2) is greater than that of imaginary circle C ₀ Is large in radius, the second imaginary cylinder C ₂ Has a central axis parallel to the long axis direction, and the second imaginary cylinder C ₂ The bottom surface of the sleeve part is positioned at the far end and the near end of the sleeve part, and the sleeve part is externally connected with the second imaginary cylinder C ₂ At least a part of the side surface of the virtual circle C ₀ The expansion portion is a virtual circle circumscribed in a cross section of a radial direction perpendicular to the longitudinal direction at a midpoint of the longitudinal direction of the expansion portion.

Thus, in the contracted state of the balloon, the proximal sleeve portion circumscribes the first imaginary cylinder C ₁ A second imaginary cylinder C circumscribing the radius and the distal sleeve portion ₂ At least one of the radii of (2) is larger than an imaginary circle C circumscribed by the expansion portion in a radial cross section at a midpoint in the longitudinal direction of the expansion portion ₀ Since the radius of (a) is large, when the balloon in the contracted state is delivered in the body cavity, the proximal sleeve portion or the distal sleeve portion can be made to abut against the body cavity wall, so that the expansion portion is less likely to abut against the body cavity wall. This can reduce the contact area of the balloon with the body cavity wall, and can improve the trackability of the balloon (the ease of following the curvature of the body cavity by the balloon during the balloon delivery in the body cavity). In addition, since the balloon can be delivered to the lesion by making it difficult for the central portion of the dilated portion to contact the body cavity wall, the dilated portion that dilates and acts on the lesion during treatment can be protected from damage, and effective treatment can be performed. Further, for example, in the case where the medicine is mounted on the expansion portion, the loss of the medicine can be prevented. In this specification, the balloon for a balloon catheter may be simply referred to as "balloon".

A balloon for a balloon catheter will be described with reference to fig. 1 to 15. Fig. 1 shows a side view of a balloon catheter according to an embodiment of the present invention. Fig. 2 is a cross-sectional view in the longitudinal direction of the balloon catheter shown in fig. 1 in an expanded state, and fig. 3 is a plan view of the balloon shown in fig. 2 from the outer protruding portion side. Fig. 4 shows a cross-sectional view of IV-IV of fig. 1. Fig. 5 is a side view of the balloon catheter shown in fig. 1 in a contracted state, and fig. 6 is a side view showing another example of the side view shown in fig. 5. Fig. 7 shows a cross-sectional view VII-VII of fig. 5, i.e., a radial cross-sectional view at a midpoint in the long axis direction of the expansion. Fig. 8 to 10 are cross-sectional views showing another example of the cross-sectional view shown in fig. 7, that is, cross-sectional views showing examples in which the length of the fin and the number of the outer protrusions are different. Fig. 11 shows a cross-sectional view XI-XI of fig. 5, that is, a radial cross-sectional view of the proximal sleeve portion, and fig. 12 shows a cross-sectional view showing another example of the cross-sectional view shown in fig. 11. Fig. 13 is a side view of a balloon for a balloon catheter according to another embodiment of the present invention in a contracted state. Fig. 14 is a radial cross-sectional view of a balloon catheter according to an embodiment of the present invention at a midpoint in the longitudinal direction of an expanded portion in a folded state of the balloon, and fig. 15 is a cross-sectional view showing another example of the cross-sectional view shown in fig. 14, that is, a cross-sectional view showing an example in which the lengths of the fins are different.

In the present invention, the proximal side refers to the direction of the balloon catheter 1 in the extending direction or the direction of the user or operator's hand side in the long axis direction x of the shaft 3, and the distal side refers to the opposite direction of the proximal side, i.e., the direction of the treatment target side. The longitudinal direction x is the same as that of the shaft 3, except for the long member such as the shaft 3. The radial direction y is a direction perpendicular to the long axis direction x and is a direction connecting the center of the balloon body 27 and a point on the circumscribing circle of the balloon body 27 in the expanded state in a cross section perpendicular to the long axis direction x. The circumferential direction z is a direction along the circumference of the circumscribed circle of the balloon body 27 in the expanded state in the cross section in the radial direction y.

As shown in fig. 1 and 2, the balloon catheter 1 includes: a shaft 3; and a balloon 2 provided outside the shaft 3. The balloon catheter 1 has a distal side and a proximal side, and the balloon 2 is disposed on the distal side of the shaft 3. The balloon catheter 1 is configured such that a fluid is supplied to the interior of the balloon 2 through the shaft 3, and inflation and deflation of the balloon 2 can be controlled by an inflator (balloon pressurizer). The fluid may be a pressurized fluid pressurized by a pump or the like.

The shaft 3 preferably has a fluid flow path inside and also has a guide wire insertion path. In order to form the shaft 3 having a fluid flow path and a guide wire insertion path therein, for example, the following structure may be used: the shaft 3 includes an outer tube 31 and an inner tube 32, and the inner tube 32 functions as an insertion passage for a guide wire and the space between the inner tube 32 and the outer tube 31 functions as a fluid flow path. In this way, in the case where the shaft 3 has a structure including the outer tube 31 and the inner tube 32, the inner tube 32 preferably extends from the distal end of the outer tube 31 and penetrates to the distal side of the balloon 2, the distal side of the balloon 2 is joined to the inner tube 32, and the proximal side of the balloon 2 is joined to the outer tube 31.

As shown in fig. 1 to 12, the balloon 2 for a balloon catheter includes: an expansion section 20; a proximal sleeve portion 21 located on the proximal side of the expansion portion 20; and a distal sleeve portion 22 which is located on a distal side from the expansion portion 20 and has: a balloon body 27 having an outer surface and an inner surface; and an outer protruding portion 60 protruding outward in the radial direction y from the outer surface of the balloon body 27 and extending in the longitudinal direction x of the balloon body 27, and satisfying at least one of the following (1) and (2) in the contracted state of the balloon 2.

(1) First imaginary cylinder C ₁ Radius r of (2) ₁ Than imaginary circle C ₀ Radius r of (2) ₀ Large, the first imaginary cylinder C ₁ Has a central axis parallel to the long axis direction x, and the first imaginary cylinder C ₁ Is positioned at the distal end and the proximal end of the proximal sleeve portion 21, and the proximal sleeve portion 21 is externally connected to the first imaginary cylinder C ₁ At least a part of the side surface of the virtual circle C ₀ Is an imaginary circle circumscribed by the expansion portion 20 in a cross section of a radial direction y perpendicular to the long axis direction x at a midpoint 20c of the long axis direction x of the expansion portion 20.

(2) A second imaginary cylinder C ₂ Radius r of (2) ₂ Than imaginary circle C ₀ Radius r of (2) ₀ Large, the second imaginary cylinder C ₂ Has a central axis parallel to the long axis direction x, and the second imaginary cylinder C ₂ Is positioned at the distal end and the proximal end of the distal sleeve portion 22, and the distal sleeve portion 22 is circumscribed by the second imaginary cylinder C ₂ At least a part of the side surface of the virtual circle C ₀ Is an imaginary circle circumscribed by the expansion portion 20 in a cross section of a radial direction y perpendicular to the long axis direction x at a midpoint 20c of the long axis direction x of the expansion portion 20.

In the contracted state of the balloon 2, the proximal sleeve portion 21 circumscribes the first imaginary cylinder C ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of which is larger than an imaginary circle C circumscribed by the expansion portion 20 in a cross section of the radial direction y at a midpoint 20C of the long axis direction x of the expansion portion 20 ₀ Radius r of (2) ₀ When the balloon 2 in the contracted state is delivered into the body cavity, the proximal sleeve portion 21 or the distal sleeve portion 22 can be made to abut against the body cavity wall, and therefore, the dilating portion 20 can be made less likely to abut against the body cavity wall. This can reduce the contact area of the balloon 2 with the body cavity wall, and can improve the trackability (body cavityEase of following the curvature of the body lumen by the balloon 2 during the delivery of the inner balloon 2). In addition, since the balloon 2 can be delivered to the lesion by making it difficult for the central portion of the dilating portion 20 to contact the body cavity wall, the dilating portion 20 that is dilated and acts on the lesion during treatment can be protected from damage, and effective treatment can be performed. Further, for example, when the medicine is mounted on the expansion unit 20, loss of the medicine can be prevented.

As shown in fig. 1 and 2, the balloon 2 has a proximal sleeve portion 21 and a distal sleeve portion 22 at positions closer to the distal side and the proximal side than the expansion portion 20, respectively. The proximal sleeve portion 21 and the distal sleeve portion 22 may be fixed to the shaft 3, or when the shaft 3 has the outer tube 31 and the inner tube 32, at least a portion of the proximal sleeve portion 21 may be fixed to the outer tube 31 and at least a portion of the distal sleeve portion 22 may be fixed to the inner tube 32.

The expansion portion 20 is preferably a portion that expands by supplying fluid to the inside of the balloon 2 through the shaft 3, and even when fluid is supplied to the inside of the balloon 2, the proximal sleeve portion 21 and the distal sleeve portion 22 located at positions closer to the position or the distal position than the expansion portion 20, respectively, do not expand. This can stabilize the fixation of the balloon 2 to the shaft 3 even in the expanded state of the balloon 2. Further, as described later, when the balloon 2 is contracted from the expanded state, the fins 29 are formed in the expanded portion 20, but when the proximal sleeve portion 21 and the distal sleeve portion 22 are not expanded, even when the balloon 2 is contracted from the expanded state, the fins 29 are not formed in the proximal sleeve portion 21 and the distal sleeve portion 22. This can be configured as follows: when the balloon 2 is delivered in the body cavity in the contracted state, the fins 29 do not abut against the body cavity wall in the proximal sleeve portion 21 and the distal sleeve portion 22.

Although not shown, the expansion unit 20 may include: a straight pipe section; a proximal cone portion located closer to the proximal side than the straight tube portion; and a distal taper portion located on a distal side from the straight tube portion. The straight tube portion preferably has the same diameter in the longitudinal direction x, and the proximal taper portion and the distal taper portion are formed so as to decrease in diameter as they are separated from the straight tube portion. The dilating portion 20 has a straight tube portion having a maximum diameter, so that when the balloon 2 is dilated in a lesion such as a stricture, the straight tube portion can be sufficiently brought into contact with the lesion to facilitate dilation or incision of the lesion. Further, since the proximal taper portion and the distal taper portion have the reduced diameters, when the balloon 2 is contracted, the outer diameters of the proximal end portion and the distal end portion of the balloon 2 can be reduced to reduce the step between the shaft 3 and the balloon 2, and thus the balloon 2 can be easily inserted into the body cavity.

As shown in fig. 1 to 4, the balloon 2 includes: a balloon body 27 having an outer surface and an inner surface; and an outer protruding portion 60 protruding outward in the radial direction y than the outer surface of the balloon main body 27 and extending in the longitudinal direction x of the balloon main body 27. The maximum length of the outer protruding portion 60 protruding outward in the radial direction y from the outer surface of the balloon main body 27 in the cross section in the radial direction y is preferably 1.2 times or more, more preferably 1.5 times or more, still more preferably 2 times or more, and still more preferably 100 times or less, 50 times or less, 30 times or less, or 10 times or less the film thickness of the balloon main body 27. The maximum length may be different in the longitudinal direction x. By the outer protruding portion 60 having the maximum length in the above range, a suitable-depth incision can be easily formed in the narrow portion, and the incision can be easily performed. Further, since the balloon 2 has the outer protruding portion 60, the strength of the balloon 2 can be improved, and excessive expansion of the balloon 2 at the time of pressurization can be suppressed.

The number of the outer protrusions 60 in the circumferential direction z of the balloon 2 may be plural as shown in fig. 1 to 8 and 11, or may be one as shown in fig. 9, 10 and 12. In the case where the balloon 2 has a plurality of outer protrusions 60 in the circumferential direction z, the plurality of outer protrusions 60 are preferably separated in the circumferential direction z, and more preferably are arranged at equal intervals in the circumferential direction z. Preferably, the separation distance is longer than the maximum circumference of the outer protrusion 60. The outer protruding portions 60 are preferably spaced apart from each other at equal intervals in the circumferential direction z, so that the balloon 2 can be easily fixed and the narrow portion can be easily cut.

The outer protruding portion 60 extending in the longitudinal direction x on the outer surface of the balloon main body 27 may be disposed at the same position in the circumferential direction z in the longitudinal direction x, that is, may be disposed straight in the longitudinal direction x as shown in fig. 3. If the outer protruding portion 60 is disposed straight, the narrow portion can be cut straight. Alternatively, although not shown, the outer protruding portion 60 may be disposed at a different position in the circumferential direction z in the longitudinal direction x, for example, may be disposed in a spiral shape so as to surround the outer surface of the balloon main body 27 in the circumferential direction z. In such an outer protruding portion, the narrow portion can be cut obliquely.

The balloon 2 preferably satisfies at least one of the following (1) and (2).

(1) The outer protruding portion 60 of the proximal sleeve portion 21 and the outer protruding portion 60 of the expansion portion 20 extend continuously in the longitudinal direction x.

(2) The outer protruding portion 60 of the distal sleeve portion 22 and the outer protruding portion 60 of the expansion portion 20 extend continuously in the longitudinal direction x.

Fig. 3 shows a configuration satisfying both (1) and (2), that is, a configuration in which the outer protruding portion 60 of the proximal sleeve portion 21, the outer protruding portion 60 of the expansion portion 20, and the outer protruding portion 60 of the distal sleeve portion 22 extend continuously in the longitudinal direction x, but at least one of (1) and (2) may be satisfied. This can further enhance the strength of the balloon 2 and further suppress excessive expansion of the balloon 2 during pressurization.

Alternatively, although not shown, the outer protruding portions 60 of the proximal sleeve portion 21, the expansion portion 20, and the distal sleeve portion 22 may not extend continuously in the longitudinal direction x, or may have a portion where the outer protruding portions 60 are not arranged, as long as the condition is satisfied: in the contracted state of the balloon 2, the proximal sleeve portion 21 circumscribes the first imaginary cylinder C ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of which is larger than an imaginary circle C circumscribed by the expansion portion 20 in a cross section of the radial direction y at a midpoint 20C of the long axis direction x of the expansion portion 20 ₀ Radius r of (2) ₀ Large. Thus, a portion having a small outer diameter in the contracted state of the balloon 2 can be provided, and the contact area between the balloon 2 and the body cavity wall can be reduced, thereby improving trackability.

As shown in fig. 4, the outer protruding portion 60 has a tip portion 61 in a cross section in the radial direction y. Since the distal end portion 61 makes it easy to form an incision in the stenosed portion, the stenosed portion can be incised while preventing peeling of the intima of the blood vessel. The distal end portion 61 is a portion of the outer protruding portion 60 protruding outward in the radial direction y than the outer surface of the balloon main body 27, and may have a shape having an acute angle as shown in fig. 4, a shape having an obtuse angle, a shape formed by a curved line, or a flat shape. From the viewpoint of ease of forming the incision, the distal end portion 61 preferably has a shape having an acute angle. The shape of the outer protruding portion 60 in the cross section in the radial direction y may be arbitrary, may be substantially triangular as shown in fig. 4, or may be polygonal, fan-shaped, wedge-shaped, convex-shaped, spindle-shaped, or the like.

As shown in fig. 5 and 7, the contracted state of the balloon 2 is a state before supplying fluid into the balloon 2 or after discharging fluid from the balloon 2, and the expanding portion 20 has, in the contracted state of the balloon 2: the portion of the inner surface of the balloon body 27 that is proximal to the shaft 3 and the tab 29. In the form shown in fig. 5 and 7, the shaft 3 has an outer tube 31 and an inner tube 32, and the expansion portion 20 has, in the contracted state of the balloon 2: the portion of the inner surface of the balloon body 27 that is in proximity to the inner tube 32 and the fins 29. Preferably in the contracted state of balloon 2, fins 29 are formed to encircle shaft 3 in circumferential direction z. Preferably, before supplying the fluid into the balloon 2, particularly in a contracted state of the balloon 2 before use, as shown in fig. 7 to 10, the fins 29 are wound around the shaft 3 in the circumferential direction z, and the fins 29 are contracted so as to be in close contact with each other in a portion where the outer protruding portion 60 is not present, and so as to be in close contact with the outer protruding portion 60 in a portion where the outer protruding portion 60 is disposed. It is preferable that the above-described structure be in a contracted state even when the balloon 2 is in a contracted state in which fluid is discharged from the temporarily expanded balloon 2 after use or the like. This makes it possible to easily reduce the virtual circle C circumscribed by the expansion portion 20 in the cross section of the radial direction y perpendicular to the longitudinal direction x at the midpoint 20C of the longitudinal direction x of the expansion portion 20 ₀ Radius r of (2) ₀ 。

As shown in fig. 5, the balloon 2 satisfies at least one of the following (1) and (2) in a contracted state.

(1) First imaginary cylinder C ₁ Radius r of (2) ₁ Than imaginary circle C ₀ Radius r of (2) ₀ Large, the first imaginary cylinder C ₁ Has a central axis parallel to the long axis direction x, and the first imaginary cylinder C ₁ Is positioned at the distal end and the proximal end of the proximal sleeve portion 21, and the proximal sleeve portion 21 is externally connected to the first imaginary cylinder C ₁ At least a part of the side surface of the virtual circle C ₀ Is an imaginary circle circumscribed by the expansion portion 20 in a cross section of the radial direction y at a midpoint 20c of the long axis direction x of the expansion portion 20.

(2) A second imaginary cylinder C ₂ Radius r of (2) ₂ Than imaginary circle C ₀ Radius r of (2) ₀ Large, the second imaginary cylinder C ₂ Has a central axis parallel to the long axis direction x, and the second imaginary cylinder C ₂ Is positioned at the distal end and the proximal end of the distal sleeve portion 22, and the distal sleeve portion 22 is circumscribed by the second imaginary cylinder C ₂ At least a part of the side surface of the virtual circle C ₀ Is an imaginary circle circumscribed by the expansion portion 20 in a cross section of the radial direction y at a midpoint 20c of the long axis direction x of the expansion portion 20.

Fig. 5 shows a configuration satisfying both of the above (1) and (2), but at least one of the above (1) and (2) may be satisfied. When both (1) and (2) are satisfied, the proximal sleeve portion 21 circumscribes the first virtual cylinder C ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ The same may be applied, or any one may be larger. With the above configuration, when the balloon 2 in the contracted state is delivered in the body cavity, the proximal sleeve portion 21 or the distal sleeve portion 22 can be made to abut against the body cavity wall, so that the expanding portion 20 can be made less likely to abut against the body cavity wall. As a result, the relatively large-area dilating portion 20 is less likely to come into contact with the body cavity wall, and therefore the contact area of the balloon 2 with the body cavity wall during delivery can be reduced, and the trackability of the balloon 2 can be improved. Further, since the dilating portion 20 is less likely to abut against the body cavity wall, the dilating portion 20 which is dilated and acts on the lesion during treatment can be protected from damage, and effective treatment can be performed. For example, a drug is mounted on the expansion portion 20In the above case, the loss of the drug can be prevented.

Here, the condition of (1) above is that the proximal sleeve portion 21 is circumscribed by the first imaginary cylinder C ₁ At least a part of the side surface of the first imaginary cylinder C ₁ Has a central axis parallel to the longitudinal axis direction x, and has bottom surfaces at the distal end and proximal end of the proximal sleeve portion 21. In other words, it is: when in the first imaginary cylinder C ₁ When the proximal sleeve portion 21 is accommodated so that the longitudinal direction x coincides with the inside of the barrel portion 21, the proximal sleeve portion 21 and the first virtual cylinder C ₁ At least a part of the side surfaces of the proximal sleeve portion 21 is in contact with the first imaginary cylinder C, and when the diameters of the proximal sleeve portion 21 are different in the longitudinal direction x, the portion having the largest diameter is in contact with the first imaginary cylinder C ₁ Is connected with the side face of the frame. The condition (2) described above with respect to the distal sleeve portion 22 can be understood in the same manner as described above.

When the proximal end of the expansion portion 20 is set to a position of 0% and the distal end is set to a position of 100% in the longitudinal direction x, the midpoint 20C of the expansion portion 20 in the longitudinal direction x corresponds to a position of 50%, but it is preferable that the proximal sleeve portion 21 circumscribes the first virtual cylinder C ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of which is larger than the radius of each virtual circle circumscribed by the expansion portion 20 in the cross section of the radial direction y at 40% and 60% of the positions. In addition, the radius r is more preferable ₁ Radius r ₂ At least one of which is larger than the radius of each imaginary circle circumscribed by the expansion portion 20 in a section of the radial direction y at 30% and 70% of the positions, and more preferably the radius r ₁ Radius r ₂ At least one of which is larger than the radius of each virtual circle circumscribed by the expansion portion 20 in a cross section of the radial direction y at 20% of the positions and 80% of the positions. Thus, when the balloon 2 in the contracted state is delivered into the body cavity, the expanded portion 20 can be made more difficult to abut against the body cavity wall, and the traceability of the balloon 2 can be improved and the expanded portion 20 can be protected more easily.

Preferably, in the case where the expansion portion 20 has a structure of a proximal cone portion, a straight tube portion, and a distal cone portion, the proximal cone portionFirst imaginary cylinder C circumscribed by sleeve portion 21 ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of which is larger than the radius of the straight tube portion. Thus, when the balloon 2 in the contracted state is conveyed in the body cavity, the straight tube portion having a relatively large area can be made difficult to abut against the body cavity wall, and the traceability of the balloon 2 can be improved and the straight tube portion can be protected.

The sleeve part is not required to be integrally connected with each imaginary cylinder. For example, as shown in FIG. 6, the distal end portion of the distal sleeve portion 22 may have a distal end portion that does not circumscribe the second imaginary cylinder C ₂ Is a part of the same. With such a configuration, the diameter of the distal end portion in the advancing direction can be reduced when the balloon 2 in the contracted state is inserted into the body cavity, and thus the insertion performance can be improved. Alternatively, although not shown, the proximal end portion of the proximal sleeve portion 21 may have a shape not circumscribed by the first imaginary cylinder C ₁ Is a part of the same. With such a configuration, the diameter of the distal end portion in the advancing direction can be reduced when the balloon 2 in the contracted state is retracted from the lesion, and thus the insertion performance can be improved.

Referring to fig. 7 to 10, a virtual circle C circumscribed in a cross section of the expansion portion 20 in a radial direction y at a midpoint 20C in a longitudinal direction x of the expansion portion 20 in a contracted state of the balloon 2 ₀ An explanation is given. Fig. 7 and 8 show a virtual circle C in the case of the balloon 2 having three outer protrusions 60 ₀ Is an example of (a). As shown in fig. 7, in the case of the balloon 2 having a relatively large diameter of the expansion portion 20, the length of the fin 29 around the balloon in the circumferential direction z is relatively long, and in this case, the fin 29 may be circumscribed with the virtual circle C ₀ . As shown in fig. 8, in the case of the balloon 2 having a relatively small diameter of the expansion portion 20, the length of the fin 29 around the circumferential direction z is relatively short, and in this case, the outer protruding portion 60 may be circumscribed by the virtual circle C ₀ . Fig. 9 and 10 show a virtual circle C in the case of the balloon 2 having one outer protruding portion 60 ₀ Is an example of (a). As shown in fig. 10, in the case of the balloon 2 having a relatively large diameter of the expansion portion 20, the length of the fin 29 around the balloon in the circumferential direction z is relatively long, and in this case, the fin 29 may be circumscribed with an imaginary circle C ₀ . As shown in fig. 9, in the example of the balloon 2 having a relatively small diameter of the expansion portion 20, the length of the fin 29 around the balloon in the circumferential direction z may be relatively short, and in this case, the outer protruding portion 60 and the fin 29 may be circumscribed with the virtual circle C ₀ . The outer protruding part 60 is externally connected with an imaginary circle C ₀ In the case of (C), the tip portion 61 may be circumscribed by the virtual circle C ₀ . In any case, the first imaginary cylinder C circumscribed by the proximal sleeve portion 21 ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of them is larger than the imaginary circle C ₀ Radius r of (2) ₀ Because of this large size, the outer projecting portion 60 and the fins 29 of the straight tube portion 20 can be made difficult to abut against the body cavity wall.

Referring to fig. 11 and 12, a first virtual cylinder C circumscribed by the proximal sleeve portion 21 in the contracted state of the balloon 2 is provided ₁ Radius r of (2) ₁ An imaginary circle C circumscribing the expansion portion 20 in a cross section of a radial direction y at a midpoint 20C of the long axis direction x of the expansion portion 20 ₀ Radius r of (2) ₀ First imaginary cylinder C in case of large ₁ An explanation is given. Fig. 11 shows a first imaginary cylinder C in the case of a balloon 2 with three outer protrusions 60 ₁ Fig. 12 shows a first imaginary cylinder C in the case of a balloon 2 with one outside protrusion 60 ₁ Is an example of (a). FIG. 11 is a sectional view XI-XI of FIG. 5, showing in FIG. 5 that the proximal sleeve portion 21 circumscribes the first imaginary cylinder C in the entire longitudinal direction x ₁ However, the balloon 2 according to the embodiment of the present invention is not limited to fig. 5, and may have a cross section shown in fig. 11 at a part of the proximal sleeve portion 21. In the same manner as in the embodiment shown in fig. 12, the balloon 2 may have a cross section shown in fig. 12 at a part of the proximal sleeve portion 21. As shown in fig. 11 and 12, the fin 29 is not formed in the contracted state of the balloon 2 even in the unexpanded proximal sleeve portion 21, and in the form shown in fig. 11, the outer protruding portion 60 can circumscribe the first virtual cylinder C ₁ . In other forms including the form shown in fig. 12, the outer protruding portion 60 and the balloon body 27 may be circumscribed by the first virtual cylinder C ₁ . First, theImaginary cylinder C ₁ As shown in fig. 11 and 12, the proximal sleeve portion 21 can be considered as a body cavity wall when the balloon 2 is conveyed in the body cavity, and can ensure a conveying path of the balloon 2 by abutting against the body cavity wall with a small contact area, thereby improving the trackability of the balloon 2.

As shown in fig. 12, for example, when one outer protruding portion 60 is provided in the proximal sleeve portion 21 and a plurality of outer protruding portions 60 are provided in the expansion portion 20, the balloon 2 is contracted so that the balloon films are in close contact with each other, and so that the fins 29 of the expansion portion 20 are in close contact with the outer protruding portions 60 at the portion where the outer protruding portions 60 are provided, so that the radius r can be made ₁ And r ₂ At least one of the ratio radii r ₀ Large.

About the second imaginary cylinder C circumscribed by the distal sleeve portion 22 in the contracted state of the balloon 2 ₂ Radius r of (2) ₂ An imaginary circle C circumscribing the expansion portion 20 in a cross section of a radial direction y at a midpoint 20C of the long axis direction x of the expansion portion 20 ₀ Radius r of (2) ₀ Second imaginary cylinder C in case of large ₂ Although not shown, the same can be understood with reference to fig. 11 and 12 used in the description of the proximal sleeve portion 21.

From the viewpoint of protection of the expansion portion 20, as shown in fig. 5 and 6, it is preferable that the proximal sleeve portion 21 circumscribes the first virtual cylinder C in the contracted state of the balloon 2 ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ An imaginary circle C, which is circumscribed by the expansion part 20 in the cross section of the radial direction y at the midpoint 20C of the long axis direction x of the expansion part 20 ₀ Radius r of (2) ₀ Large. From the viewpoint of ease of insertion during delivery of the balloon 2, it is preferable that the proximal sleeve portion 21 circumscribe the first virtual cylinder C ₁ Radius r of (2) ₁ Or a second imaginary cylinder C circumscribed by the distal sleeve part 22 ₂ Radius r of (2) ₂ Any one of the expansion sections 20 is larger than an imaginary circle C circumscribed by the expansion section 20 in a cross section of a radial direction y at a midpoint 20C of a long axis direction x of the expansion section 20 ₀ Radius r of (2) ₀ Large. In particular, a first imaginary cylinder C circumscribed by only the proximal sleeve portion 21 ₁ Radius r of (2) ₁ Radius r of ratio ₀ In the case of a large size, the outer diameter of the distal sleeve portion 22, which is the distal end side when inserted into the body cavity, can be suppressed, and the balloon 2 can be easily transported in the body cavity. In addition, radius r ₁ Radius r of ratio ₀ When the balloon 2 is transported in the body cavity, the proximal sleeve portion 21 is brought into contact with the body cavity wall to support the body cavity wall on the proximal side of the balloon 2, whereby the transport path of the balloon 2 can be ensured, the expansion portion 20 is less likely to be brought into contact with the body cavity wall, and the traceability of the balloon 2 can be improved and the protection of the expansion portion 20 can be achieved. Radius r of the distal sleeve portion 22 ₂ Radius r of ratio ₀ In the case of a large size, the distal sleeve portion 22 is in contact with the body cavity wall during the conveyance of the balloon 2, and the conveyance path of the balloon 2 can be ensured, so that there is an advantage that the insertion performance of the balloon 2 can be prevented from being deteriorated due to disturbance of the contracted state of the balloon 2, such as the distal end of the balloon membrane being rolled up due to the abutment of the expansion portion 20 with the body cavity wall.

Radius r ₀ Radius r ₁ Radius r ₂ The radial length y of the outer protruding portion 60 in the cross section of the radial direction y can be changed in the expansion portion 20, the proximal sleeve portion 21, and the distal sleeve portion 22, but the radius r can be adjusted by a method of contracting the expansion portion 20 regardless of the radial length y of the outer protruding portion 60 ₀ As a result, the radius r can be adjusted ₀ And radius r ₁ Radius r ₂ Is a relationship of (3). That is, when the balloon 2 is contracted, the balloon 2 is contracted in such a manner that the balloon films are adhered to each other at the portion where the outer protruding portion 60 is not provided, and in such a manner that the fins 29 are adhered to the outer protruding portion 60 at the portion where the outer protruding portion 60 is provided, whereby the radius r can be made ₀ Radius r of ratio ₁ Radius r ₂ Is small. As long as this method is adopted, the radius r can be adjusted regardless of the length of the radial direction y in the cross section of the radial direction y of the expansion portion 20, the proximal sleeve portion 21, the distal sleeve portion 22, and the outer protruding portion 60 ₀ As a result, the radius r can be adjusted ₀ And radius r ₁ Radius r ₂ Is a relationship of (3).

As shown in fig. 13, the expansion portion 20 preferably has a main section 20m from which 10% of the longitudinal direction x is removed from each of the distal end and the proximal end, and at least one of the following (1) and (2) is satisfied in the contracted state of the balloon 2.

(1) First imaginary cylinder C ₁ Radius r of (2) ₁ Compared with a third imaginary cylinder C ₃ Radius r of (2) ₃ Large, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction x, and the third imaginary cylinder C ₃ The bottom surface of the main section 20m is positioned at the far-position end and the near-position end of the main section 20m, and the main section 20m is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c).

(2) A second imaginary cylinder C ₂ Radius r of (2) ₂ Compared with a third imaginary cylinder C ₃ Radius r of (2) ₃ Large, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction x, and the third imaginary cylinder C ₃ The bottom surface of the main section 20m is positioned at the far-position end and the near-position end of the main section 20m, and the main section 20m is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c).

A first imaginary cylinder C circumscribed by the proximal sleeve portion 21 in the contracted state of the balloon 2 ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ A third virtual cylinder C circumscribing the main section 20m of the expansion section 20 ₃ Radius r of (2) ₃ Since the balloon 2 in a contracted state is transported in the body cavity, the entire main section 20m of the dilating portion 20 can be made difficult to abut against the body cavity wall. This can further reduce the contact area of the balloon 2 with the body cavity wall, and can further improve the trackability of the balloon 2. Further, since the entire main section 20m of the expansion unit 20 is made difficult to be brought into contact with the body cavity wall and the balloon 2 is delivered to the lesion, the main section 20m which expands and acts on the lesion during treatment can be protected from damage, and for example, when a drug is mounted on the main section 20m, loss of the drug can be prevented.

The main section 20m is a section obtained by removing 10% of the longitudinal direction x from the distal end and the proximal end of the expansion section 20, that is, removing the portion of the expansion section 20 having the smallest diameter in the expanded state.In other words, the main section 20m is a section having a diameter equal to or larger than a certain value in the expanded state. In this way, in the contracted state of the balloon 2, the fins 29 having a certain or more length, which are circumferentially wound in the circumferential direction z, are formed in the main section 20m, and the balloon 2 is contracted so that the fins 29 are in close contact with the outer protruding portion 60, whereby the radius r can be made ₀ Radius r of ratio ₁ Radius r ₂ Is small.

In the above-described configuration, the third virtual cylinder C circumscribed to the main section 20m of the expansion section 20 ₃ Radius r of (2) ₃ In other words, the expansion portion 20 may be larger than an imaginary circle C circumscribed by the expansion portion 20 in a cross section of a radial direction y perpendicular to the long axis direction x at a midpoint 20C of the long axis direction x of the expansion portion 20 ₀ Radius r of (2) ₀ Is also equal to the imaginary circle C ₀ Radius r of (2) ₀ Or may be smaller than the imaginary circle C ₀ Radius r of (2) ₀ . If considering the first imaginary cylinder C circumscribed by the proximal sleeve portion 21 ₁ Radius r of (2) ₁ A second imaginary cylinder C circumscribed with the distal sleeve portion 22 ₂ Radius r of (2) ₂ At least one of the ratio radii r ₀ If the volume is large, it is preferable that the third imaginary cylinder C circumscribes the main section 20m ₃ Radius r of (2) ₃ Radius r of ratio ₀ Large. In this way, the diameter of the central portion of the expansion portion 20 can be further suppressed at the proximal end portion or the distal end portion of the balloon 2 in the contracted state, and it is preferable from the viewpoints of improvement of the trackability and protection of the expansion portion 20.

Preferably, in the contracted state of the balloon 2, the balloon 2 is folded. The balloon 2 in the collapsed state can be formed by folding the balloon 2 in the collapsed state before supplying the fluid into the balloon 2 or after discharging the fluid from the balloon 2 by hand, various folding machines, or the like. In the folded state, the flap 29 is folded so as to securely surround the shaft 3, and does not float from the shaft 3, so that the flap 29 can be prevented from abutting against the body cavity wall during conveyance. Thereby, the radius r can be easily reduced ₀ Therefore, the dilating portion 20 is more difficult to abut against the wall of the body cavity, and the trackability of the balloon 2 can be further improved. In addition, since the dilating portion 20 is less likely to abut against the wall of the body cavity, it is possible to protect the patient from the disease by dilating during the treatmentThe expansion portion 20 of the transformation portion is not damaged.

For example, as shown in fig. 14 and 15, in the folded state of the balloon 2, the flap 29 may be folded firmly, and the outer protruding portion 60 may be deformed in the circumferential direction z of the flap 20. By folding in this way, the radius r can be reduced more easily ₀ . As a method of folding the balloon 2 in this way, there are mentioned a method of stacking the balloon 2 by hand, various folding machines, and the like. By folding the balloon 2 in this way, the radius r can be adjusted regardless of the length of the radial direction y of the outer protrusion 60 ₀ As a result, the radius r can be adjusted ₀ And radius r ₁ Radius r ₂ Is a relationship of (3). That is, the outer protruding portion 60 deforms in the circumferential direction z of the vane 29, so that the radius r can be reduced ₀ Can make radius r ₀ Radius r of ratio ₁ Radius r ₂ Is small.

Further, since the main section 20m is a section having the fins 29 with a length equal to or longer than a certain length surrounding in the circumferential direction z, if the outer protruding portion 60 is folded so as to be deformed in the circumferential direction of the fins 29 over the entire main section 20m of the expansion portion 20, the third virtual cylinder C circumscribing the main section 20m can be easily reduced ₃ Radius r of (2) ₃ Can make radius r ₃ Radius r of ratio ₁ Radius r ₂ Is small. This makes it possible to make the entire main section 20m less likely to come into contact with the body cavity wall, and to further reduce the contact area of the balloon 2 with the body cavity wall.

The outer protruding portion 60 preferably has a distal end portion 61 in a cross section in the radial direction y, and at least one of the following (1) and (2) is satisfied in a contracted state of the balloon 2.

(1) The distal end portion 61 is circumscribed by the first imaginary cylinder C at the proximal sleeve portion 21 ₁ At least a portion of the side of (c).

(2) The distal end portion 61 circumscribes the second imaginary cylinder C at the distal sleeve portion 22 ₂ At least a portion of the side of (c).

The area of the sleeve portion circumscribing the virtual cylinder can be reduced by the distal end portion 61 circumscribing the virtual cylinder. The imaginary cylinder can also be seenIn order to transport the balloon 2 in the body cavity, the sleeve portion is abutted against the body cavity wall with a small contact area, whereby the transport path of the balloon 2 can be ensured and the trackability of the balloon 2 can be improved. In this case, as shown in fig. 11, only the distal end portion 61 may be externally connected to the virtual cylinder, as shown in fig. 12, the distal end portion 61 and the balloon body 27 may be externally connected to the virtual cylinder, or, although not shown, the distal end portion 61 and a portion other than the distal end portion 61, for example, a portion other than the distal end portion 61 of the outer protruding portion 60 may be externally connected. FIGS. 11 and 12 show a first imaginary cylinder C circumscribed by ₁ But is circumscribed by the second imaginary cylinder C ₂ The distal sleeve portion 22 of (c) can be similarly understood with reference to fig. 11 and 12.

(1) Only the tip portion 61 is circumscribed by the first imaginary cylinder C at the proximal sleeve portion 21 ₁ At least a portion of the side of (c).

(2) Only the distal end portion 61 is circumscribed by the second imaginary cylinder C at the distal sleeve portion 22 ₂ At least a portion of the side of (c).

By connecting only the distal end portion 61 to the virtual cylinder, the area of the sleeve portion connecting to the virtual cylinder can be further reduced. The virtual cylinder can also be regarded as a body cavity wall when the balloon 2 is conveyed in the body cavity, and the sleeve portion is brought into contact with the body cavity wall with a smaller contact area, whereby the conveying path of the balloon 2 can be ensured and the trackability of the balloon 2 can be further improved. In this case, for example, as shown in fig. 11, the sleeve portion may be configured such that a plurality of outer protruding portions 60 are arranged apart from each other in the circumferential direction z. FIG. 11 shows a first imaginary cylinder C circumscribed by ₁ But about the proximal sleeve portion 21 of (C) and the second imaginary cylinder C ₂ The circumscribed distal sleeve portion 22 can also be understood in the same manner with reference to fig. 11.

Preferably, in the contracted state of the balloon 2, the expansion portion 20 has a tab 29 and the tab 29 circumscribes the imaginary circle C ₀ . As can be seen from a comparison of fig. 7 and 8 or fig. 9 and 10: by adjusting the balloon body 27The diameter can be adjusted so that the length of the fin 29 around the circumferential direction z is adjusted, but the fin 29 is formed so that the fin 29 is circumscribed by the virtual circle C by forming the fin 29 to have a certain length or more ₀ Is a structure of (a). As long as the fin 29 is circumscribed by the virtual circle C as shown in fig. 7 and 10, for example ₀ The outer protruding portion 60 is easily protected from damage, and even if the dilating portion 20 is in contact with the body lumen wall, the outer protruding portion 60 acting on the lesion is less likely to be in contact with the body lumen wall when the balloon 2 is delivered in the body lumen, so that the outer protruding portion 60 can be prevented from acting on the body lumen wall at an undesired position.

Although 3 tabs 29 are shown in fig. 7 to 10, the number of tabs 29 is not particularly limited as long as the balloon 2 can be contracted, and for example, it is preferably 2 or more, more preferably 3, but may be 4 or more or 5 or more. The number of fins 29 is preferably 10 or less, more preferably 8 or less, and still more preferably 6 or less, for example. The balloon 2 can be easily contracted as long as the number of the fins 29 is within the above range.

In the contracted state of the balloon 2, the expansion portion 20 preferably has the fins 29, and the outer protruding portion 60 is disposed at a position other than the fins 29. If the outer protruding portion 60 is disposed at a position other than the flap 29, the balloon 2 can be easily contracted because the outer protruding portion 60 does not hinder the wrapping of the flap 29. In addition, since the outer protruding portion 60 is disposed at a position other than the flap 29, the outer protruding portion 60 can be easily covered with the flap 29 in the contracted state of the balloon 2. Thus, the fin 29 is easily formed to circumscribe the virtual circle C in the contracted state of the balloon 2 ₀ Is a structure of (a).

Next, a balloon for a balloon catheter according to another embodiment of the present invention will be described with reference to fig. 16 to 18. Fig. 16 is a side view of a balloon for a balloon catheter according to still another embodiment of the present invention in a contracted state. Fig. 17 shows a sectional view of XVII-XVII of fig. 16, that is, a radial sectional view of the distal sleeve part, and fig. 18 shows a sectional view showing another example of the sectional view shown in fig. 17.

As shown in fig. 16, preferably in the contracted state of balloon 2,a first imaginary cylinder C at the proximal sleeve part 21 ₁ Radius r of (2) ₁ Than an imaginary circle C at the expansion portion 20 ₀ Radius r of (2) ₀ Large, second imaginary cylinder C at distal sleeve part 22 ₂ Radius r of (2) ₂ Than imaginary circle C ₀ Radius r of (2) ₀ Is small. By forming such a structure, the outer diameter of the distal sleeve portion 22 on the distal end side when inserted into the body cavity can be suppressed, and the balloon 2 can be easily transported in the body cavity. In addition, radius r ₁ Radius r of ratio ₀ As a result, when the balloon 2 is conveyed in the body cavity, the proximal sleeve portion 21 is brought into contact with the body cavity wall to support the body cavity wall on the proximal side of the balloon 2, whereby the conveyance path of the balloon 2 can be ensured, the expansion portion 20 is made difficult to be brought into contact with the body cavity wall, and the traceability of the balloon 2 can be improved and the protection of the expansion portion 20 can be achieved. By forming the structure as described above, the balloon 2 can be easily inserted, the trackability is improved, and the protection of the expansion portion 20 is easy.

As shown in fig. 17, the above-described structure may be formed by shortening the length of the outer protruding portion 60 in the radial direction y of the distal sleeve portion 22 in the cross section thereof, or may be formed without providing the outer protruding portion 60 in the distal sleeve portion 22. By shortening the length of the outer protruding portion 60 in the radial direction y or by eliminating the outer protruding portion 60, the second virtual cylinder C circumscribed by the distal sleeve portion 22 can be reduced ₂ Radius r of (2) ₂ 。

Alternatively, to reduce the radius r ₂ As shown in fig. 18, the distal sleeve portion 22 preferably includes an inner protruding portion 70, and the inner protruding portion 70 protrudes inward in the radial direction y from the inner surface of the balloon main body 27 and extends in the longitudinal direction x. In this case, as shown in fig. 18, an outer protruding portion 60 having a short length in the radial direction y in the cross section in the radial direction y may be provided, or the outer protruding portion 60 may not be provided, although not shown. By providing the inner protruding portion 70, the strength of the balloon 2 can be improved and excessive expansion of the balloon 2 at the time of pressurization can be suppressed even when the length of the outer protruding portion 60 in the radial direction y is short or the outer protruding portion 60 is not provided. An outside is also provided along with the inside protrusion 70 In the case of the protruding portion 60, the inner protruding portion 70 and the outer protruding portion 60 are preferably provided at the same position in the circumferential direction z. This makes it easier to increase the strength of the balloon 2 and suppress excessive expansion of the balloon 2 during pressurization.

As shown in fig. 16, the expansion portion 20 preferably has a main section 20m in which 10% of the longitudinal direction x is removed from each of the distal end and the proximal end, and the first virtual cylinder C in the proximal sleeve portion 21 is preferably in the contracted state of the balloon 2 ₁ Radius r of (2) ₁ Compared with a third imaginary cylinder C ₃ Radius r of (2) ₃ Large, second imaginary cylinder C at distal sleeve part 22 ₂ Radius r of (2) ₂ Compared with a third imaginary cylinder C ₃ Radius r of (2) ₃ Small, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction x, and the third imaginary cylinder C ₃ The bottom surface of the main section 20m is positioned at the far-position end and the near-position end of the main section 20m, and the main section 20m is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c). With such a configuration, when the balloon 2 in the contracted state is delivered into the body cavity, the entire main section 20m of the expansion section 20 can be made difficult to abut against the body cavity wall. In addition, the outer diameter of the distal sleeve portion 22, which is the distal end side when inserted into the body cavity, can be suppressed, and the balloon 2 can be easily transported in the body cavity. Radius r ₁ Radius r of ratio ₃ When the balloon 2 is transported in the body cavity, the proximal sleeve portion 21 is brought into contact with the body cavity wall to support the body cavity wall on the proximal side of the balloon 2, whereby the transport path of the balloon 2 can be ensured, the entire main section 20m of the expansion portion 20 is made difficult to be brought into contact with the body cavity wall, and the balloon 2 can be easily inserted, and the trackability is improved, and the protection of the expansion portion 20 is facilitated.

Examples of the material constituting the balloon main body 27 include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polyester resins such as polyethylene terephthalate and polyester elastomers, polyurethane resins such as polyurethane and polyurethane elastomers, polyamide resins such as polyphenylene sulfide resins, polyamides and polyamide elastomers, fluorine resins, silicone resins, and natural rubbers such as latex rubber. Only 1 kind of these may be used, or 2 or more kinds may be used in combination. Among them, polyamide resins, polyester resins, and polyurethane resins are suitably used. In particular, from the viewpoint of film formation and flexibility of the balloon main body 27, an elastomer resin is preferably used. For example, nylon 12, nylon 11, and the like are preferable as the resin constituting the balloon main body 27, and nylon 12 is more preferable from the viewpoint of being relatively easy to mold at the time of blow molding. In addition, from the viewpoint of film formation and flexibility of the balloon main body 27, polyamide elastomers such as polyether ester amide elastomers and polyamide ether elastomers are preferably used. Among them, polyether ester amide elastomer is preferably used in view of the high yield strength and the good dimensional stability of the balloon main body 27.

Preferably, the outer protrusion 60 is composed of the same material as the balloon body 27. If the outer protruding portion 60 is made of the same material as the balloon main body 27, the flexibility of the balloon 2 can be maintained, and the outer protruding portion 60 can be made difficult to damage the outer surface of the balloon main body 27. Preferably, the balloon body 27 and the lateral protrusions 60 are integrally formed. This can prevent the outer protruding portion 60 from falling off the balloon main body 27. In the form in which the inner protruding portion 70 is formed, the inner protruding portion 70 is preferably made of the same material as the balloon main body 27 for the same reason as described above.

The balloon 2 can be manufactured by, for example, disposing a cylindrical parison 200 made of a resin as shown in fig. 19 in a mold having a groove in an inner cavity, and performing biaxial stretch blow molding. The outer protruding portion 60 can be formed, for example, by inserting the parison 200 into the cavity of the mold, causing the thick wall portion 220 of the parison 200 to enter the groove of the mold, and introducing a fluid into the cavity 210 of the parison 200 to expand the parison 200. The length of the radial direction y in the cross section of the radial direction y of the outer protruding portion 60 can be adjusted by the thickness of the thick wall portion 220 of the parison 200 and the depth of the groove of the mold. The inner protruding portion 70 can be formed by, for example, pressing the thick portion 220 of the parison 200 against a portion of the mold having no groove, and introducing a fluid into the cavity 210 of the parison 200 to expand the parison 200. In order to form the outer protruding portion 60 and the inner protruding portion 70 having short lengths in the radial direction y in the cross section of the radial direction y, the thick wall portion 220 of the parison 200 is pressed against the shallow groove portion of the mold, and fluid is introduced into the cavity 210 of the parison 200 to expand the parison 200. As the material constituting the preform 200, the description of the material constituting the balloon main body 27 can be referred to.

Examples of the material constituting the shaft 3 include polyamide resin, polyester resin, polyurethane resin, polyolefin resin, fluorine resin, vinyl chloride resin, silicone resin, natural rubber, and the like. Only 1 kind of these may be used, or 2 or more kinds may be used in combination. Among them, the material constituting the shaft 3 is preferably at least one of polyamide resin, polyolefin resin, and fluorine resin. This can improve the sliding property of the surface of the shaft 3, and can improve the insertion property of the balloon catheter 1 into the body cavity.

The joining of the balloon 2 and the shaft 3 may be performed by bonding or welding with an adhesive, attaching an annular member to a position where the end of the balloon 2 overlaps the shaft 3, or by caulking. Among these, the balloon 2 and the shaft 3 are preferably joined by welding. By welding the balloon 2 and the shaft 3, even if the balloon 2 is repeatedly inflated and deflated, the joint between the balloon 2 and the shaft 3 is hardly released, and the joint strength between the balloon 2 and the shaft 3 can be easily improved.

As shown in fig. 1, the balloon catheter 1 may be provided with a pivot (hub) 4 on the proximal side of the shaft 3, and the pivot 4 may be provided with a fluid injection portion 7 that communicates with a flow path of fluid supplied to the interior of the balloon 2. In addition, the pivot portion 4 preferably has a guide wire insertion portion 5 that communicates with the insertion path of the guide wire. By providing the balloon catheter 1 with the pivot portion 4 having the fluid injection portion 7 and the guide wire insertion portion 5, the operation of supplying the fluid into the balloon 2 to expand and contract the balloon 2 and the operation of delivering the balloon catheter 1 to the treatment site along the guide wire can be easily performed. The balloon 2 according to The embodiment of The present invention can be applied not only to a so-called OTW (Over-The-Wire) type balloon catheter in which a guide Wire is inserted from The distal side to The proximal side of The shaft 3 as shown in fig. 1, but also to a so-called RX (quick Exchange) type balloon catheter in which a guide Wire is inserted from The distal side to The halfway of The shaft to The proximal side.

The shaft 3 and the pivot 4 are joined by, for example, adhesion by an adhesive, welding, or the like. Of these, the shaft 3 and the pivot 4 are preferably joined by adhesion. By bonding the shaft 3 and the pivot 4, for example, when the shaft 3 is made of a material having high flexibility and the pivot 4 is made of a material having high rigidity, the material constituting the shaft 3 is different from the material constituting the pivot 4, so that the joint strength between the shaft 3 and the pivot 4 can be improved to improve the durability of the balloon catheter 1.

The present application claims the benefit of priority based on japanese patent application No. 2021-8307 filed on 1/21 of 2021. The entire contents of the specifications of Japanese patent application No. 2021-8307 applied to month 21 of 2021 are incorporated herein by reference.

Description of the reference numerals

Balloon catheter; 2. balloon; shaft; a pivot; a guidewire insertion; a fluid injection portion; expansion part; midpoint of the expansion part in the long axis direction; main section of the expansion section; proximal sleeve portion; distal sleeve portion; a balloon body; fins; an outside tube; inner tube; outside protrusion; 61. the front end; medial protrusion; parison is a green body; inner cavity of parison; thick wall portion of parison; c (C) ₀ .. an imaginary circle circumscribed by the midpoint of the expansion portion in the longitudinal direction; c (C) ₁ .. the proximal sleeve portion circumscribes a first imaginary cylinder; c (C) ₂ .. the second imaginary cylinder circumscribed by the distal sleeve portion; c (C) ₃ .. a third imaginary cylinder circumscribed by the main section of the expansion portion; r is (r) ₀ .. imaginary circle C ₀ Radius of (2); r is (r) ₁ .. first imaginary cylinder C ₁ Radius of (2); r is (r) ₂ .. A second imaginary cylinder C ₂ Radius of (2); r is (r) ₃ .. third imaginary cylinder C ₃ Radius of (2); x. long axis direction; y. radial; z. it is circumferential.

Claims

1. A balloon for a balloon catheter, comprising: an expansion section; a proximal sleeve portion located closer to the proximal side than the expansion portion; and a distal sleeve portion positioned on a distal side of the expansion portion,

the balloon for balloon catheter is characterized in that,

the device comprises: a balloon body having an outer surface and an inner surface; and an outer protruding portion protruding radially outward from an outer surface of the balloon main body and extending in a longitudinal direction of the balloon main body,

at least one of the following (1) and (2) is satisfied in a contracted state of the balloon,

(1) First imaginary cylinder C ₁ Radius of (2) is greater than that of imaginary circle C ₀ Is large in radius, the first imaginary cylinder C ₁ Has a central axis parallel to the long axis direction, and the first imaginary cylinder C ₁ Is positioned at the far end and the near end of the near sleeve part, and the near sleeve part is externally connected with the first imaginary cylinder C ₁ At least a part of the side face of the imaginary circle C ₀ Is an imaginary circle circumscribed by the expansion portion in a radial cross section perpendicular to the long axis direction at a midpoint of the long axis direction of the expansion portion,

(2) A second imaginary cylinder C ₂ Radius of (2) is greater than that of imaginary circle C ₀ Is large in radius, the second imaginary cylinder C ₂ Has a central axis parallel to the long axis direction, and the second imaginary cylinder C ₂ Is positioned at the far end and the near end of the far sleeve part, and the far sleeve part is externally connected with the second imaginary cylinder C ₂ At least a part of the side face of the imaginary circle C ₀ The expansion portion is an imaginary circle circumscribed in a cross section in a radial direction perpendicular to the longitudinal direction at a midpoint of the longitudinal direction of the expansion portion.

2. The balloon for a balloon catheter according to claim 1, wherein,

the expansion portion has a main section from which 10% of the longitudinal direction is removed from each of the distal end and the proximal end, and satisfies at least one of the following (1) and (2) in a contracted state of the balloon,

(1) The first imaginary cylinder C ₁ Is greater than the radius of the third imaginary cylinder C ₃ Is large in radius of theThird imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the third imaginary cylinder C is positioned at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c),

(2) The second imaginary cylinder C ₂ Is greater than the radius of the third imaginary cylinder C ₃ Is large in radius, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the third imaginary cylinder C is positioned at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c).

3. The balloon for a balloon catheter according to claim 1 or 2, wherein,

in the contracted state of the balloon, the balloon is folded.

4. The balloon for a balloon catheter according to any one of claim 1 to 3, wherein,

the outer protruding portion has a distal end portion in the radial cross section, and satisfies at least one of the following (1) and (2) in a contracted state of the balloon,

(1) The front end part is externally connected to the first imaginary cylinder C at the proximal sleeve part ₁ At least a portion of the side of (c),

(2) The distal sleeve portion is externally connected to the second imaginary cylinder C ₂ At least a portion of the side of (c).

5. The balloon for a balloon catheter according to any one of claims 1 to 4, wherein,

(1) Only the front end portion is externally connected to the proximal sleeve portionThe first imaginary cylinder C ₁ At least a portion of the side of (c),

(2) Only the distal end portion is circumscribed by the second imaginary cylinder C at the distal sleeve portion ₂ At least a portion of the side of (c).

6. The balloon for a balloon catheter according to any one of claims 1 to 5, wherein,

in the contracted state of the balloon, the expansion portion has a fin circumscribing the virtual circle C ₀ 。

7. The balloon for a balloon catheter according to any one of claims 1 to 6, wherein,

in the contracted state of the balloon, the expansion portion has a fin, and the outer protruding portion is disposed at a position other than the fin.

8. The balloon for a balloon catheter according to any one of claims 1 to 7, wherein,

satisfies at least one of the following (1) and (2),

(1) The outer protruding portion of the proximal sleeve portion and the outer protruding portion of the expanding portion extend continuously in the long axis direction,

(2) The outer protruding portion of the distal sleeve portion and the outer protruding portion of the expanding portion extend continuously in the long axis direction.

9. The balloon for a balloon catheter according to any one of claims 1 to 8, wherein,

in the contracted state of the balloon, the first imaginary cylinder C at the proximal sleeve part ₁ Is smaller than the imaginary circle C at the expansion part ₀ Is larger than the second imaginary cylinder C at the distal sleeve part ₂ Radius of (C) is greater than the imaginary circle C ₀ Is small.

10. The balloon for a balloon catheter according to claim 9, wherein,

the expansion portion has a main section from which 10% of the longitudinal direction is removed from each of a distal end and a proximal end, and the first virtual cylinder C at the proximal sleeve portion in the contracted state of the balloon ₁ Radius of (C) is greater than that of the third imaginary cylinder C ₃ Is larger than the second imaginary cylinder C at the distal sleeve part ₂ Is smaller than the radius of the third imaginary cylinder C ₃ Is small in radius, the third imaginary cylinder C ₃ Has a central axis parallel to the long axis direction, and the third imaginary cylinder C ₃ The bottom surface of the third imaginary cylinder C is positioned at the far-position end and the near-position end of the main section, and the main section is externally connected with the third imaginary cylinder C ₃ At least a portion of the side of (c).

11. The balloon for a balloon catheter according to claim 9 or 10, wherein,

the distal sleeve portion has an inner protruding portion protruding radially inward from an inner surface of the balloon body and extending in the longitudinal direction.

12. The balloon for a balloon catheter according to any one of claims 1 to 11, wherein,

the outer protrusion is composed of the same material as the balloon body.