Balloon for balloon catheter

Abstract

Provided is a balloon capable of improving tracking performance and protecting an expanded portion of the balloon when the balloon in a contracted state is delivered into a body lumen. A balloon catheter balloon (2) has a balloon main body (27) and an outer protrusion (60) that satisfies (1) and / or (2) below in a contracted state of the balloon (2). (1) A first imaginary cylinder C1 circumscribing a proximal side sleeve portion (21) has a radius r1 that is larger than a radius r0 of an imaginary circle C0 circumscribing an expanded portion (20) at a midpoint (20c) of the expanded portion (20). (2) A second imaginary cylinder C2 circumscribing a distal side sleeve portion (22) has a radius r2 that is larger than the radius r0 of the imaginary circle C0 circumscribing the expanded portion (20) at the midpoint (20c) of the expanded portion (20).

Description

Technical Field

[0001] This invention relates to balloons for balloon catheters. Background Technology

[0002] Angina pectoris, myocardial infarction, and other diseases can occur due to the formation of narrowed sections in the inner wall of blood vessels caused by calcification and other hardening. As one treatment option, angioplasty is a procedure that uses a balloon catheter to dilate the narrowed section. Angioplasty is a low-invasive treatment that does not require open-chest surgery like bypass surgery and is widely performed.

[0003] In angiogenesis surgery, conventional balloon catheters sometimes fail to dilate stenotic lesions hardened by calcification or other factors. Alternatively, methods using indwelling dilators called stents can be employed to dilate the stenosis; however, this treatment can also lead to in-stent-restenosis (ISR) lesions, characterized by excessive neointimal proliferation and subsequent re-stenosis. In ISR lesions, the neointimal layer is soft and prone to slippage, making it easy for the balloon to shift from the lesion during dilation, potentially damaging the vessel.

[0004] As balloon catheters capable of dilating stenosis even in calcified lesions and ISR lesions, balloon catheters have been developed that incorporate protrusions or braided layers and scoring elements within the balloon for engaging the stenosis. For example, Patent Document 1 discloses a balloon catheter with scoring elements made of a polymer material with a higher rigidity than the polymer material forming the balloon body, the scoring elements being flattened at one and the other ends of the balloon. Patent Document 2 discloses a scoring balloon structure where the height of the scoring element decreases along the pointed shape of the balloon, and Patent Document 3 discloses a balloon catheter with an outer protrusion in the straight portion of the balloon and an inner protrusion in the conical portion. In Patent Documents 1-3, the height of the scoring element decreases at both ends of the balloon, or an inner protrusion is provided instead of an outer protrusion. In contrast, there are also balloon catheters with a high protrusion where the protrusion of the protrusion located in the distal conical portion is greater than the protrusion of the protrusion located in the straight portion of the balloon (Patent Document 4).

[0005] Patent Document 1: U.S. Patent Application Publication No. 2016 / 0128718

[0006] Patent Document 2: Japanese Patent Publication No. 2014-506140

[0007] Patent Document 3: International Publication No. 2020 / 012851

[0008] Patent Document 4: International Publication No. 2020 / 012850

[0009] The balloon catheter is inserted into the body cavity in a contracted and folded state and delivered to the treatment site. Therefore, in the balloon catheters disclosed in Patent Documents 1-3, to facilitate insertion into the body cavity, the height of the scoring element at the front end of the balloon is suppressed to prevent an increase in the outer diameter, attempting to improve the balloon's permeability. However, in such balloon catheters, the height of the scoring element is suppressed at both ends of the balloon, causing the balloon's expansion portion to abut against the body cavity wall during delivery, increasing the contact area between the balloon and the body cavity wall. As a result, the balloon's tracking ability within the body cavity's curvature (the ease with which the balloon follows the curvature of the body cavity during delivery) may decrease. Furthermore, since the balloon's expansion portion abuts against the body cavity wall to deliver the balloon to the lesion, there is a possibility that the expansion portion of the balloon, which expands to act on the lesion during treatment, may be damaged during delivery, hindering treatment. In the balloon catheter disclosed in the aforementioned patent document 4, the height of the protrusion at the front lateral cone is high, which is designed to facilitate the formation of an incision at the lesion site in the expanded state. However, there is room for improvement in terms of improving the tracking performance when delivering the balloon in the contracted state to the lesion site and protecting the balloon expansion portion during delivery. Summary of the Invention

[0010] In view of the above, the object of the present invention is to provide a balloon catheter that can improve trackability and protect the balloon's expansion portion when delivering a balloon in a contracted state within a body cavity.

[0011] One embodiment of the balloon catheter of the present invention, which can solve the above-mentioned problems, is a balloon catheter having: an expansion portion; a proximal sleeve portion located closer to the expansion portion; and a distal sleeve portion located distal to the expansion portion, wherein the balloon catheter has: a balloon body having an outer surface and an inner surface; and an outer protrusion that protrudes radially outward from the outer surface of the balloon body and extends in the long axis direction of the balloon body, and satisfies at least one of (1) and (2) below in the balloon's contracted state.

[0012] (1) The radius of the first imaginary cylinder C1 is larger than the radius of the imaginary circle C0. The first imaginary cylinder C1 has a central axis parallel to the long axis direction, and the bottom surface of the first imaginary cylinder C1 is located at the distal end and proximal end of the proximal sleeve portion. The proximal sleeve portion is circumscribed on at least a portion of the side surface of the first imaginary cylinder C1. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the long axis direction at the midpoint of the expansion portion in the long axis direction of the expansion portion.

[0013] (2) The radius of the second imaginary cylinder C2 is larger than the radius of the imaginary circle C0. The second imaginary cylinder C2 has a central axis parallel to the major axis direction, and the bottom surface of the second imaginary cylinder C2 is located at the distal end and proximal end of the distal sleeve portion. The distal sleeve portion is circumscribed on at least a portion of the side surface of the second imaginary cylinder C2. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the major axis direction at the midpoint of the expansion portion in the major axis direction.

[0014] Preferably, the dilatation portion has a main section obtained by removing 10% of the long axis from both the distal and proximal ends, and satisfies at least one of the following (1) and (2) when the balloon is in a contracted state.

[0015] (1) The radius of the first imaginary cylinder C1 is larger than the radius of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the major axis direction, and the bottom surface of the third imaginary cylinder C3 is located at the far end and proximal end of the main interval. The main interval is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3.

[0016] (2) The radius of the second imaginary cylinder C2 is larger than the radius of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the direction of the major axis, and the bottom surface of the third imaginary cylinder C3 is located at the far end and the proximal end of the main interval. The main interval is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3.

[0017] Preferably, the balloon is folded when it is in the contracted state.

[0018] Preferably, the outer protrusion has a front end in the radial section, and satisfies at least one of (1) and (2) below in the contracted state of the balloon.

[0019] (1) At least a portion of the front end is connected to the side of the first imaginary cylinder C1 outside the proximal sleeve portion.

[0020] (2) The front end portion is connected to at least a portion of the side of the second imaginary cylinder C2 outside the distal sleeve portion.

[0021] Preferably, the outer protrusion has a front end in the radial section, and satisfies at least one of (1) and (2) below in the contracted state of the balloon.

[0022] (1) Only the front end portion is connected to at least a portion of the side of the first imaginary cylinder C1 outside the proximal sleeve portion.

[0023] (2) Only the front end portion is connected to at least a portion of the side of the second imaginary cylinder C2 outside the distal sleeve portion.

[0024] Preferably, in the contracted state of the balloon, the expansion portion has winglets, which are circumscribed in an imaginary circle C0.

[0025] Preferably, in the contracted state of the balloon, the expansion portion has winglets, and the outer protrusion is positioned in a location other than the winglets.

[0026] Preferably, at least one of (1) and (2) below is satisfied.

[0027] (1) The outer protrusion of the proximal sleeve portion and the outer protrusion of the expansion portion extend continuously in the long axis direction.

[0028] (2) The outer protrusion of the distal sleeve portion and the outer protrusion of the expansion portion extend continuously in the long axis direction.

[0029] Preferably, in the balloon's contracted state, the radius of the first imaginary cylinder C1 at the proximal sleeve portion is larger than the radius of the imaginary circle C0 at the expansion portion, and the radius of the second imaginary cylinder C2 in the distal sleeve portion is smaller than the radius of the imaginary circle C0. In this case, the expansion portion preferably has a main section obtained by removing 10% of the long axis direction from both the distal and proximal ends. In the balloon's contracted state, the radius of the first imaginary cylinder C1 at the proximal sleeve portion is larger than the radius of the third imaginary cylinder C3, and the radius of the second imaginary cylinder C2 at the distal sleeve portion is smaller than the radius of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the long axis direction, and the bottom surface of the third imaginary cylinder C3 is located at the distal and proximal ends of the main section. The main section is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3. In this case, it is further advantageous that the distal sleeve portion has an inner protrusion that protrudes radially inward from the inner surface of the balloon body and extends in the long axis direction.

[0030] Preferably, the outer protrusion is made of the same material as the balloon body.

[0031] According to the balloon for the above-mentioned balloon catheter, in the balloon's contracted state, 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 dilation portion. Therefore, when delivering a contracted balloon within a body cavity, the balloon's tracking ability can be improved, and the balloon's dilation portion can be protected. Attached Figure Description

[0032] Figure 1 This is a side view of a balloon catheter according to one embodiment of the present invention.

[0033] Figure 2 express Figure 1 The cross-sectional view along the long axis of the balloon catheter in its expanded state.

[0034] Figure 3 Indicates from Figure 2A top view of the lateral protrusion of the balloon shown.

[0035] Figure 4 express Figure 1 Sectional view IV-IV.

[0036] Figure 5 express Figure 1 The side view of the balloon catheter in the contracted state.

[0037] Figure 6 Indicates Figure 5 Another example of a side view shown.

[0038] Figure 7 express Figure 5 Sectional view VII-VII.

[0039] Figure 8 Indicates Figure 7 Another example of a sectional view shown.

[0040] Figure 9 Indicates Figure 7 Another example of a sectional view shown.

[0041] Figure 10 Indicates Figure 7 Another example of a sectional view shown.

[0042] Figure 11 express Figure 5 XI-XI sectional view.

[0043] Figure 12 Indicates Figure 11 Another example of a sectional view shown.

[0044] Figure 13 A side view showing the balloon of a balloon catheter according to another embodiment of the present invention in its contracted state.

[0045] Figure 14 This is a radial cross-sectional view taken at the midpoint of the long axis of the expansion portion of a balloon catheter in a folded state, according to one embodiment of the present invention.

[0046] Figure 15 Indicates Figure 14 Another example of a sectional view shown.

[0047] Figure 16 This is a side view showing the balloon of a balloon catheter in a contracted state according to yet another embodiment of the present invention.

[0048] Figure 17 express Figure 16 Sectional view of XVII-XVII.

[0049] Figure 18 Indicates Figure 17 Another example of a sectional view shown.

[0050] Figure 19 This is a perspective view of the preform before expansion according to one embodiment of the present invention. Detailed Implementation

[0051] The present invention will now be specifically described based on embodiments. However, the present invention is not limited to these embodiments, and it can undoubtedly be implemented with appropriate modifications within the scope of the preceding / following descriptions, all of which are included within the technical scope of the present invention. Furthermore, in the various drawings, for convenience, there are instances where shaded lines, component reference numerals, etc., are omitted. In such cases, please refer to the specification and other drawings. Additionally, the dimensions of various components in the drawings are primarily advantageous for understanding the features of the present invention, and therefore may differ from the actual dimensions.

[0052] The balloon for a balloon catheter according to an embodiment of the present invention has: an expansion portion; a proximal sleeve portion located closer to the expansion portion than the expansion portion; and a distal sleeve portion located distal to the expansion portion. The balloon for a balloon catheter has: a balloon body having an outer surface and an inner surface; and an outer protrusion that protrudes radially outward from the outer surface of the balloon body and extends in the long axis direction of the balloon body. In the contracted state of the balloon, at least one of (1) and (2) below is satisfied.

[0053] (1) The radius of the first imaginary cylinder C1 is larger than the radius of the imaginary circle C0. The first imaginary cylinder C1 has a central axis parallel to the long axis direction, and the bottom surface of the first imaginary cylinder C1 is located at the distal end and proximal end of the proximal sleeve portion. The proximal sleeve portion is circumscribed on at least a portion of the side surface of the first imaginary cylinder C1. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the long axis direction at the midpoint of the expansion portion in the long axis direction of the expansion portion.

[0054] (2) The radius of the second imaginary cylinder C2 is larger than the radius of the imaginary circle C0. The second imaginary cylinder C2 has a central axis parallel to the major axis direction, and the bottom surface of the second imaginary cylinder C2 is located at the distal end and proximal end of the distal sleeve portion. The distal sleeve portion is circumscribed on at least a portion of the side surface of the second imaginary cylinder C2. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the major axis direction at the midpoint of the expansion portion in the major axis direction.

[0055] Thus, in the balloon's contracted state, at least one of the radii of the first imaginary cylinder C1 circumscribed outside the proximal sleeve portion and the second imaginary cylinder C2 circumscribed outside the distal sleeve portion is larger than the radius of the imaginary circle C0 circumscribed outside the radial section at the midpoint of the long axis of the expansion portion. Therefore, when delivering a contracted balloon within the body cavity, the expansion portion is less likely to come into contact with the body cavity wall by having either the proximal or distal sleeve portion abut against it. This reduces the contact area between the balloon and the body cavity wall, improving balloon tracking ability (the ease with which the balloon follows the curvature of the body cavity during intracavitary balloon delivery). Furthermore, by delivering the balloon to the lesion with the central portion of the expansion portion less likely to come into contact with the body cavity wall, damage to the expansion portion that expands and acts on the lesion during treatment can be prevented, enabling effective treatment. Also, for example, when the expansion portion carries medication, medication loss can be prevented. In this manual, the balloon catheter is sometimes referred to simply as a "balloon".

[0056] Reference Figures 1-15 Instructions are provided regarding the use of balloon catheters. Figure 1 This is a side view of a balloon catheter according to one embodiment of the present invention. Figure 2 express Figure 1 The image shows a cross-sectional view along the long axis of the balloon catheter in its inflated state. Figure 3 Indicates from Figure 2 A top view of the lateral protrusion of the balloon shown. Figure 4 express Figure 1 Sectional view IV-IV. Figure 5 express Figure 1 The image shows a side view of the balloon catheter in its contracted state. Figure 6 Indicates Figure 5 Another example of a side view shown. Figure 7 express Figure 5 Section VII-VII, that is, the radial section at the midpoint of the major axis of the expansion. Figures 8-10 Indicates Figure 7 The cross-sectional views shown are of another example, namely cross-sectional views showing different lengths of the winglets and the number of outer protrusions. Figure 11 express Figure 5 The XI-XI sectional view, i.e., the radial sectional view of the proximal sleeve portion. Figure 12 Indicates Figure 11 Another example of a sectional view shown. Figure 13 A side view showing the balloon of a balloon catheter according to another embodiment of the present invention in its contracted state. Figure 14This is a radial cross-sectional view taken at the midpoint of the long axis of the expansion portion of the balloon in a folded state, according to one embodiment of the present invention. Figure 15 Indicates Figure 14 Another example of the sectional view shown is a sectional view showing examples with different blade lengths.

[0057] In this invention, the proximal side refers to the direction on the user's or surgeon's hand side along the extension direction of the balloon catheter 1 or the long axis direction x of the shaft 3, while the distal side refers to the opposite direction of the proximal side, i.e., the direction on the side of the object to be treated. Even components other than the long strip-shaped shaft 3 have the same long axis direction x as the shaft 3. The radial direction y is the direction perpendicular to the long axis direction x and is the direction connecting the center of the balloon body 27 to a point on the circumference of the balloon body 27 in the inflated state in a cross-section perpendicular to the long axis direction x. The circumferential direction z is the direction along the circumference of the circumference of the balloon body 27 in the inflated state in a cross-section along the radial direction y.

[0058] like Figure 1 and Figure 2 As shown, the balloon catheter 1 has: a shaft 3; and a balloon 2, disposed outside the shaft 3. The balloon catheter 1 has a distal side and a proximal side, with the balloon 2 disposed distal to the shaft 3. The balloon catheter 1 is configured to supply fluid to the interior of the balloon 2 via the shaft 3, and the expansion and contraction of the balloon 2 can be controlled using an inflator (balloon pressurizer). The fluid can also be a pressurized fluid pressurized by a pump or the like.

[0059] Preferably, the shaft 3 has a fluid flow path inside and a guidewire insertion path. To form a structure in which the shaft 3 has both a fluid flow path and a guidewire insertion path inside, an example can be formed as follows: the shaft 3 has an outer tube 31 and an inner tube 32, the inner tube 32 functions as the guidewire insertion path, and the space between the inner tube 32 and the outer tube 31 functions as a fluid flow path. Thus, in the case of the shaft 3 having an outer tube 31 and an inner tube 32, preferably the inner tube 32 extends from the distal end of the outer tube 31 and protrudes to a position distal to the balloon 2, the distal side of the balloon 2 engages with the inner tube 32, and the proximal side of the balloon 2 engages with the outer tube 31.

[0060] like Figures 1-12 As shown, the balloon 2 for the balloon catheter has: an expansion portion 20; a proximal sleeve portion 21 located closer to the expansion portion 20; and a distal sleeve portion 22 located more distal to the expansion portion 20, and has: a balloon body 27 having an outer surface and an inner surface; and a lateral protrusion 60 protruding radially y from the outer surface of the balloon body 27 and extending in the long axis direction x of the balloon body 27, satisfying at least one of (1) and (2) below in the contracted state of the balloon 2.

[0061] (1) The radius r1 of the first imaginary cylinder C1 is larger than the radius r0 of the imaginary circle C0. The first imaginary cylinder C1 has a central axis parallel to the major axis direction x, and the bottom surface of the first imaginary cylinder C1 is located at the distal end and proximal end of the proximal sleeve portion 21. The proximal sleeve portion 21 is externally connected to at least a portion of the side surface of the first imaginary cylinder C1. The imaginary circle C0 is an imaginary circle externally connected to the expansion portion 20 in a radial y section perpendicular to the major axis direction x at the midpoint 20c of the expansion portion 20 at the major axis direction x.

[0062] (2) The radius r2 of the second imaginary cylinder C2 is larger than the radius r0 of the imaginary circle C0. The second imaginary cylinder C2 has a central axis parallel to the major axis direction x, and the bottom surface of the second imaginary cylinder C2 is located at the distal end and proximal end of the distal sleeve portion 22. The distal sleeve portion 22 is externally connected to at least a portion of the side surface of the second imaginary cylinder C2. The imaginary circle C0 is an imaginary circle externally connected to the expansion portion 20 in a radial y section perpendicular to the major axis direction x at the midpoint 20c of the expansion portion 20 at the major axis direction x.

[0063] When the balloon 2 is in its contracted state, at least one of the radius r1 of the first imaginary cylinder C1 circumscribed by the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumscribed by the distal sleeve portion 22 is larger than the radius r0 of the imaginary circle C0 circumscribed by the expansion portion 20 in the radial y section at the midpoint 20c of the major axis direction x of the expansion portion 20. Therefore, when delivering the balloon 2 in its contracted state into the body cavity, the expansion portion 20 can be made to be less likely to come into contact with the body cavity wall by having either the proximal sleeve portion 21 or the distal sleeve portion 22 abut against the body cavity wall. As a result, the contact area of ​​the balloon 2 with the body cavity wall can be reduced, and the tracking ability of the balloon 2 (the ease with which the balloon 2 follows the curvature of the body cavity during delivery of the balloon 2 into the body cavity) can be improved. Furthermore, the central portion of the dilation section 20 is designed to prevent it from pressing against the body cavity wall, thus ensuring that the balloon 2 is delivered to the lesion site. This protects the dilation section 20 from damage during treatment, allowing for effective treatment. Additionally, when the dilation section 20 carries medication, medication loss can be prevented.

[0064] like Figure 1 and Figure 2 As shown, the balloon 2 has a proximal sleeve portion 21 and a distal sleeve portion 22 at positions closer to the position and distal to the position of the expansion portion 20, respectively. It is possible to form a structure in which at least a portion of the proximal sleeve portion 21 and the distal sleeve portion 22 is fixed to the shaft 3. When the shaft 3 has an outer tube 31 and an inner tube 32, it is possible to form a structure in which at least a portion of the proximal sleeve portion 21 is fixed to the outer tube 31, and at least a portion of the distal sleeve portion 22 is fixed to the inner tube 32.

[0065] The preferred expansion section 20 is the portion that expands by supplying fluid to the interior of the balloon 2 through the shaft 3. Even when fluid is supplied to the interior of the balloon 2, the proximal sleeve section 21 and the distal sleeve section 22, located closer to the proximal or distal side of the expansion section 20, do not expand. Therefore, the balloon 2 and the shaft 3 can be stably fixed even when the balloon 2 is in the expanded state. Furthermore, as described later, if the balloon 2 is contracted from the expanded state, a flap 29 is formed in the expansion section 20. However, if the proximal sleeve section 21 and the distal sleeve section 22 do not expand, then even when the balloon 2 is contracted from the expanded state, the flap 29 will not form in the proximal sleeve section 21 and the distal sleeve section 22. Thus, a structure can be formed such that when the balloon 2 is delivered into the body cavity in the contracted state, the flap 29 does not abut against the body cavity wall in the proximal sleeve section 21 and the distal sleeve section 22.

[0066] Although not illustrated, the dilation section 20 may also include: a straight tube; a proximal conical section located closer to the side of the straight tube; and a distal conical section located distal to the side of the straight tube. Preferably, the straight tube has the same diameter in the long axis direction x, and the proximal and distal conical sections are formed to narrow as they move away from the straight tube. The dilation section 20 has a straight tube with the largest diameter, so that when the balloon 2 is dilated in a lesion such as a stenosis, the straight tube can also make sufficient contact with the lesion, making it easy to dilate or cut the lesion. In addition, the narrowed proximal and distal conical sections can reduce the outer diameter of the proximal and distal ends of the balloon 2 when the balloon 2 is contracted, thereby reducing the step difference between the axis 3 and the balloon 2, and thus making it easier to insert the balloon 2 into the body cavity.

[0067] like Figures 1-4 As shown, the balloon 2 has: a balloon body 27 having an outer surface and an inner surface; and a lateral protrusion 60 that protrudes radially outward from the outer surface of the balloon body 27 and extends along the long axis direction x of the balloon body 27. In a cross-section along the radial y-axis, the maximum length by which the lateral protrusion 60 protrudes radially outward from the outer surface of the balloon body 27 is preferably at least 1.2 times the membrane thickness of the balloon body 27, more preferably at least 1.5 times, and even more preferably at least 2 times. It is also permissible to have a length of less than 100 times, less than 50 times, less than 30 times, or less than 10 times. Furthermore, this maximum length may vary along the long axis direction x. With the lateral protrusion 60 having a maximum length within the aforementioned range, it is easy to form an incision of appropriate depth in the narrow portion, making incision easier. Furthermore, by having the lateral protrusion 60, the strength of the balloon 2 can be improved, and excessive expansion of the balloon 2 during pressurization can be suppressed.

[0068] The number of lateral protrusions 60 on the circumferential z of balloon 2 can also be as follows Figures 1 to 8 as well as Figure 11There can be multiple as shown, or as... Figure 9 , Figure 10 as well as Figure 12 As shown, this is one. When the balloon 2 has multiple lateral protrusions 60 in the circumferential direction z, the multiple lateral protrusions 60 are preferably separated in the circumferential direction z, more preferably arranged at equal intervals in the circumferential direction z. Preferably, the separation distance is longer than the maximum circumference of the lateral protrusions 60. The lateral protrusions 60 are separated in the circumferential direction z, preferably arranged at equal intervals, thereby facilitating the fixation of the balloon 2 and the incision of the stenotic portion.

[0069] The lateral protrusion 60 extending along the long axis x on the outer surface of the balloon body 27 can also be positioned at the same location in the circumferential direction z along the long axis x, i.e., as shown in the figure. Figure 3 As shown, it is arranged vertically along the long axis x. If the outer protrusion 60 is arranged vertically, it can cut through the narrow portion vertically. Alternatively, although not shown, the outer protrusion 60 can also be arranged at different positions in the circumferential direction z along the long axis x, for example, in a spiral shape that surrounds the outer surface of the balloon body 27 in the circumferential direction z. If it is such an outer protrusion, it can cut through the narrow portion obliquely.

[0070] The balloon 2 is preferably satisfied with at least one of (1) and (2) below.

[0071] (1) The outer protrusion 60 of the proximal sleeve portion 21 and the outer protrusion 60 of the expansion portion 20 extend continuously in the long axis direction x.

[0072] (2) The outer protrusion 60 of the distal sleeve portion 22 and the outer protrusion 60 of the expansion portion 20 extend continuously in the long axis direction x.

[0073] Figure 3 The diagram shows a configuration that satisfies both (1) and (2) above, namely, the outer protrusion 60 of the proximal sleeve portion 21, the outer protrusion 60 of the expansion portion 20, and the outer protrusion 60 of the distal sleeve portion 22 extend continuously in the long axis direction x, but it is sufficient to satisfy at least one of (1) and (2) above. This further enhances the strength of the balloon 2 and further suppresses excessive expansion of the balloon 2 during pressurization.

[0074] Alternatively, although not illustrated, the outer protrusions 60 of the proximal sleeve portion 21, the expansion portion 20, and the distal sleeve portion 22 may not extend continuously in the long axis direction x, and there may be portions without the outer protrusions 60, provided that the following condition is met: in the contracted state of the balloon 2, at least one of the radius r1 of the first imaginary cylinder C1 circumscribed by the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumscribed by the distal sleeve portion 22 is larger than the radius r0 of the imaginary circle C0 circumscribed by the expansion portion 20 in the radial y-section at the midpoint 20c of the long axis direction x of the expansion portion 20. This allows for a smaller outer diameter portion of the balloon 2 in the contracted state, reducing the contact area between the balloon 2 and the body cavity wall and improving tracking performance.

[0075] like Figure 4 As shown, the lateral protrusion 60 has a front end 61 in a radial y-section. The front end 61 facilitates the formation of an incision in the stenosis, thus preventing dissection of the vascular intima. The front end 61 is the portion of the lateral protrusion 60 that protrudes radially outward from the outer surface of the balloon body 27, and can have features such as... Figure 4 The acute angle shown can also have an obtuse angle, a curved shape, or a flat shape. Considering the ease of forming the cut, it is preferable that the front end 61 has an acute angle. The shape of the radial y-section of the outer protrusion 60 can be arbitrary, or it can be as follows: Figure 4 The shape shown is roughly a triangle, but it can also be a polygon, sector, wedge, convex shape, spindle shape, etc.

[0076] like Figure 5 and Figure 7 As shown, the contracted state of balloon 2 is either before fluid is supplied to the interior of balloon 2 or after fluid is discharged from the interior of balloon 2. In the contracted state of balloon 2, the expansion portion 20 has: a portion of the inner surface of the balloon body 27 that is close to the shaft 3 and a wing 29. Figure 5 and Figure 7 In the illustrated configuration, the shaft 3 has an outer tube 31 and an inner tube 32. In the contracted state of the balloon 2, the expansion portion 20 includes: a portion of the inner surface of the balloon body 27 that approaches the inner tube 32 and a wing 29. Preferably, in the contracted state of the balloon 2, the wing 29 is formed to surround the shaft 3 in the circumferential direction z. Preferably, before supplying fluid to the interior of the balloon 2, particularly in the contracted state of the balloon 2 before use, such as... Figures 7-10As shown, the wing 29 surrounds the axis 3 in the circumferential direction z. In the portion without the outer protrusion 60, the balloon membranes are tightly attached to each other, and in the portion with the outer protrusion 60, the wing 29 is tightly attached to the outer protrusion 60. Furthermore, it is preferable that even in the contracted state after the balloon 2 has been used and fluid has been discharged from the temporarily expanded balloon 2, the structure remains in the contracted state described above. As a result, the radius r0 of the imaginary circle C0 circumscribed in the cross section perpendicular to the major axis direction x at the midpoint 20c of the expansion portion 20 in the major axis direction x can be easily reduced.

[0077] like Figure 5 As shown, balloon 2 satisfies at least one of (1) and (2) below when it is in a contracted state.

[0078] (1) The radius r1 of the first imaginary cylinder C1 is larger than the radius r0 of the imaginary circle C0. The first imaginary cylinder C1 has a central axis parallel to the major axis direction x, and the bottom surface of the first imaginary cylinder C1 is located at the distal end and proximal end of the proximal sleeve portion 21. The proximal sleeve portion 21 is externally connected to at least a portion of the side surface of the first imaginary cylinder C1. The imaginary circle C0 is an imaginary circle externally connected to the radial y section of the expansion portion 20 at the midpoint 20c of the major axis direction x of the expansion portion 20.

[0079] (2) The radius r2 of the second imaginary cylinder C2 is larger than the radius r0 of the imaginary circle C0. The second imaginary cylinder C2 has a central axis parallel to the major axis direction x, and the bottom surface of the second imaginary cylinder C2 is located at the distal end and proximal end of the distal sleeve portion 22. The distal sleeve portion 22 is externally connected to at least a portion of the side surface of the second imaginary cylinder C2. The imaginary circle C0 is an imaginary circle externally connected to the radial y section of the expansion portion 20 at the midpoint 20c of the major axis direction x of the expansion portion 20.

[0080] Figure 5The diagram shows a configuration that satisfies both (1) and (2) above, but it is sufficient if at least one of (1) and (2) is satisfied. When both (1) and (2) are satisfied, the radius r1 of the first imaginary cylinder C1 circumferentially attached to the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumferentially attached to the distal sleeve portion 22 can be the same, or either one can be larger. With the above structure, when the balloon 2 in a contracted state is delivered into the body cavity, the expansion portion 20 is made difficult to contact the body cavity wall by having either the proximal sleeve portion 21 or the distal sleeve portion 22 abut against the body cavity wall. As a result, the larger expansion portion 20 becomes less likely to contact the body cavity wall, thus reducing the contact area of ​​the balloon 2 with the body cavity wall during delivery and improving the tracking ability of the balloon 2. Furthermore, since the expansion portion 20 is less likely to contact the body cavity wall, the expansion portion 20 that expands and acts on the lesion during treatment can be protected from damage, enabling effective treatment. Furthermore, for example, when the expansion section 20 is equipped with a drug, the loss of the drug can be prevented.

[0081] Here, the condition (1) above is that the proximal sleeve portion 21 is externally connected to at least a portion of the side surface of the first imaginary cylinder C1, which has a central axis parallel to the major axis direction x, and has a bottom surface at both the distal and proximal ends of the proximal sleeve portion 21. In other words, when the proximal sleeve portion 21 is housed inside the first imaginary cylinder C1 in a manner consistent with the major axis direction x, the proximal sleeve portion 21 is in contact with at least a portion of the side surface of the first imaginary cylinder C1, and when the diameter of the proximal sleeve portion 21 is different in the major axis direction x, the portion with the largest diameter is in contact with the side surface of the first imaginary cylinder C1. The condition (2) above regarding the distal sleeve portion 22 can also be understood in the same way as above.

[0082] When the proximal end of the expansion portion 20 is set to 0% and the distal end to 100% in the major axis direction x, the midpoint 20c of the expansion portion 20 in the major axis direction x corresponds to the 50% position. However, it is preferable that at least one of the radius r1 of the first imaginary cylinder C1 circumscribed by the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumscribed by the distal sleeve portion 22 is larger than the radius of each imaginary circle circumscribed in the radial y-section of the expansion portion 20 at the 40% and 60% positions. Furthermore, it is more preferable that at least one of the radii r1 and r2 is larger than the radius of each imaginary circle circumscribed in the radial y-section of the expansion portion 20 at the 30% and 70% positions, and even more preferably that at least one of the radii r1 and r2 is larger than the radius of each imaginary circle circumscribed in the radial y-section of the expansion portion 20 at the 20% and 80% positions. Therefore, when the balloon 2 in a contracted state is delivered into the body cavity, the expansion portion 20 becomes less likely to come into contact with the body cavity wall, making it easier to improve the tracking capability of the balloon 2 and protect the expansion portion 20.

[0083] Preferably, when the expansion section 20 has a structure comprising a proximal conical section, a straight tube section, and a distal conical section, at least one of the radius r1 of the first imaginary cylinder C1 connected to the proximal sleeve section 21 and the radius r2 of the second imaginary cylinder C2 connected to the distal sleeve section 22 is larger than the radius of the straight tube section. Therefore, when the balloon 2 in a contracted state is delivered into the body cavity, the relatively large straight tube section is less likely to abut against the body cavity wall, thus improving the tracking capability of the balloon 2 and protecting the straight tube section.

[0084] It is not necessary for the sleeve portion to be externally circumscribed to each imaginary cylinder. For example, Figure 6 As shown, the distal end of the distal sleeve portion 22 may have a portion that is not externally connected to the second imaginary cylinder C2. With this structure, the diameter of the anterior end in the direction of travel can be reduced when the balloon 2 in its contracted state is inserted into the body cavity, thereby improving insertion patency. Alternatively, although not shown, the proximal end of the proximal sleeve portion 21 may also have a portion that is not externally connected to the first imaginary cylinder C1. With this structure, the diameter of the anterior end in the direction of travel can be reduced when the balloon 2 in its contracted state is retracted from the lesion, thereby improving insertion patency.

[0085] Reference Figures 7-10 The imaginary circle C0 circumscribed in the radial y section of the expansion portion 20 at the midpoint 20c of the major axis direction x of the expansion portion 20 when the balloon 2 is in the contracted state will be explained. Figure 7 and Figure 8 An example of an imaginary circle C0 is shown in the case of a balloon 2 with three lateral protrusions 60. For example... Figure 7As shown, in the example of a balloon 2 with a relatively large diameter in the expansion portion 20, the length of the wing 29 encircling in the circumferential direction z is relatively long. In this case, the wing 29 can be circumscribed by an imaginary circle C0. Figure 8 As shown, in the example of a balloon 2 with a relatively small diameter of expansion portion 20, the length of the wing 29 surrounding in the circumferential direction z is relatively short. In such cases, the outer protrusion 60 may be circumscribed to the imaginary circle C0. Figure 9 and Figure 10 An example of an imaginary circle C0 is shown in the case of a balloon 2 with an outer protrusion 60. For example... Figure 10 As shown, in the example of a balloon 2 with a relatively large diameter in the expansion portion 20, the length of the wing 29 encircling in the circumferential direction z is relatively long. In this case, the wing 29 can be circumscribed by an imaginary circle C0. Figure 9 As shown, in the example of a balloon 2 with a relatively small diameter of the expansion portion 20, the length of the wing 29 encircling in the circumferential direction z is relatively short. In this case, the outer protrusion 60 and the wing 29 may be externally connected to the imaginary circle C0. When the outer protrusion 60 is externally connected to the imaginary circle C0, the front end portion 61 may be externally connected to the imaginary circle C0. In any case, at least one of the radius r1 of the first imaginary cylinder C1 externally connected to the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 externally connected to the distal sleeve portion 22 is larger than the radius r0 of the imaginary circle C0, thus making it difficult for the outer protrusion 60 of the straight tube portion 20 and the wing 29 to abut against the body cavity wall.

[0086] Reference Figure 11 and Figure 12 The first imaginary cylinder C1, in the contracted state of the balloon 2, is described in the case where the radius r1 of the first imaginary cylinder C1 circumferentially connected to the proximal sleeve portion 21 is larger than the radius r0 of the imaginary circle C0 circumferentially connected to the expansion portion 20 in the radial y section at the midpoint 20c of the major axis direction x of the expansion portion 20. Figure 11 An example of a first imaginary cylinder C1 with a balloon 2 having three outer protrusions 60 is shown. Figure 12 An example of a first imaginary cylinder C1 is shown in the case of a balloon 2 having an outer protrusion 60. Figure 11 yes Figure 5 XI-XI sectional view, Figure 5 The diagram shows the proximal sleeve portion 21 externally circumscribed in the entire long axis direction x to the first imaginary cylinder C1, but the balloon 2 involved in the embodiments of the present invention is not limited to this. Figure 5 As long as a portion of the proximal sleeve portion 21 has Figure 11 The cross-section shown is sufficient. Figure 12 Similarly, in the configuration shown, as long as the balloon 2 has a portion of the proximal sleeve 21 Figure 12 The cross-section shown is sufficient. For example... Figure 11 and Figure 12 As shown, in the non-expanding proximal sleeve portion 21, no wings 29 are formed even in the contracted state of the balloon 2. Figure 11 In the configuration shown, the outer protrusion 60 can be externally connected to the first imaginary cylinder C1. Including... Figure 12 Other configurations, including the one shown, may involve the outer protrusion 60 and the balloon body 27 externally connected to the first imaginary cylinder C1. The first imaginary cylinder C1 can also be considered as the wall of the body cavity during balloon 2 delivery within the body cavity, such as... Figure 11 and Figure 12 As shown, the proximal sleeve portion 21 abuts against the body cavity wall with a smaller contact area, thereby ensuring the delivery path of the balloon 2 and improving the tracking performance of the balloon 2.

[0087] like Figure 12 As shown, for example, when a lateral protrusion 60 is provided in the proximal sleeve portion 21 and multiple lateral protrusions 60 are provided in the expansion portion 20, the balloon membrane is also tightly attached to each other, and the balloon 2 is contracted in the portion where the lateral protrusions 60 are provided by the flaps 29 of the expansion portion 20 tightly attached to the lateral protrusions 60, so that at least one of the radii r1 and r2 is larger than the radius r0.

[0088] Regarding the second imaginary cylinder C2 circumscribed outside the distal sleeve portion 22 in the contracted state of balloon 2, where the radius r2 is larger than the radius r0 of the imaginary circle C0 circumscribed outside the expansion portion 20 in the radial y section at the midpoint 20c of the major axis direction x of the expansion portion 20, although not shown in the figure, it can be referred to in the description of the proximal sleeve portion 21 above. Figure 11 and Figure 12 The same understanding applies.

[0089] From the perspective of protection of the expansion section 20, such as Figure 5 and Figure 6As shown, preferably, in the contracted state of the balloon 2, both the radius r1 of the first imaginary cylinder C1 circumscribed outside the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumscribed outside the distal sleeve portion 22 are larger than the radius r0 of the imaginary circle C0 circumscribed outside the expansion portion 20 in the radial y section at the midpoint 20c of the major axis direction x of the expansion portion 20. From the viewpoint of ease of insertion during balloon 2 delivery, it is preferable that either the radius r1 of the first imaginary cylinder C1 circumscribed outside the proximal sleeve portion 21 or the radius r2 of the second imaginary cylinder C2 circumscribed outside the distal sleeve portion 22 is larger than the radius r0 of the imaginary circle C0 circumscribed outside the expansion portion 20 in the radial y section at the midpoint 20c of the major axis direction x of the expansion portion 20. Especially when the radius r1 of the first imaginary cylinder C1 connected only to the proximal sleeve portion 21 is larger than the radius r0, the outer diameter of the distal sleeve portion 22, which becomes the anterior end side, can be suppressed when inserted into the body cavity, making the delivery of the balloon 2 within the body cavity easier. Furthermore, since the radius r1 is larger than the radius r0, when the balloon 2 is delivered within the body cavity, the proximal sleeve portion 21 abuts against the body cavity wall to support the body cavity wall on the proximal side of the balloon 2. This ensures the delivery path of the balloon 2 and makes it difficult for the expansion portion 20 to abut against the body cavity wall, thereby improving the trackability of the balloon 2 and protecting the expansion portion 20. When the radius r2 of the distal sleeve portion 22 is larger than the radius r0, the distal sleeve portion 22 abuts against the body cavity wall during balloon 2 delivery, which can ensure the delivery path of balloon 2. Therefore, it has the advantage of preventing the balloon 2 from deteriorating due to the disruption of the balloon 2's contraction state caused by the balloon membrane rolling up due to the expansion portion 20 abutting against the body cavity wall.

[0090] Radius r0, radius r1, and radius r2 can also be adjusted by changing the length of the radial y in the radial y section of the outer protrusion 60 through the expansion portion 20, the proximal sleeve portion 21, and the distal sleeve portion 22. However, regardless of the length of the radial y of the outer protrusion 60, radius r0 can be adjusted by contracting the expansion portion 20, thereby allowing adjustment of the relationship between radius r0 and radii r1 and r2. That is, when the balloon 2 is contracted, the balloon 2 is contracted such that the balloon membranes are tightly attached to each other in the portion without the outer protrusion 60, and the flaps 29 are tightly attached to the outer protrusion 60 in the portion where the outer protrusion 60 is located, thereby making radius r0 smaller than at least one of radius r1 and radius r2. Regardless of the length of the radial y in the radial y section of the expansion portion 20, the proximal sleeve portion 21, the distal sleeve portion 22, and the outer protrusion 60, the radius r0 can be adjusted, and as a result, the relationship between the radius r0 and the radii r1 and r2 can be adjusted.

[0091] like Figure 13As shown, the preferred expansion portion 20 has a main interval 20m obtained by removing 10% of the long axis direction x from the distal end and the proximal end respectively, and satisfies at least one of (1) and (2) below when the balloon 2 is in a contracted state.

[0092] (1) The radius r1 of the first imaginary cylinder C1 is larger than the radius r3 of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the major axis direction x, and the bottom surface of the third imaginary cylinder C3 is located at the far end and near end of the main interval 20m. The main interval 20m is circumscribed to at least a portion of the side surface of the third imaginary cylinder C3.

[0093] (2) The radius r2 of the second imaginary cylinder C2 is larger than the radius r3 of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the major axis direction x, and the bottom surface of the third imaginary cylinder C3 is located at the far end and near end of the main interval 20m. The main interval 20m is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3.

[0094] When the balloon 2 is in its contracted state, at least one of the radii r1 of the first imaginary cylinder C1 connected to the proximal sleeve portion 21 and the second imaginary cylinder C2 connected to the distal sleeve portion 22 is larger than the radius r3 of the third imaginary cylinder C3 connected to the main section 20m of the expansion portion 20. Therefore, when the balloon 2 in its contracted state is delivered into the body cavity, the entire main section 20m of the expansion portion 20 is unlikely to come into contact with the body cavity wall. This further reduces the contact area of ​​the balloon 2 with the body cavity wall, thus improving the tracking ability of the balloon 2. In addition, by delivering the balloon 2 to the lesion site with the entire main section 20m of the expansion portion 20 unlikely to come into contact with the body cavity wall, damage to the main section 20m that expands and acts on the lesion site during treatment can be prevented, for example, preventing drug loss when the main section 20m is carrying medication.

[0095] The main interval 20m is obtained by removing 10% of the long axis x from both the distal and proximal ends of the expansion portion 20, that is, by removing the portion of the expansion portion 20 at its most contracted diameter in the expanded state. In other words, the main interval 20m is an interval with a diameter of a certain or greater in the expanded state. Thus, in the contracted state of the balloon 2, a wing 29 of a certain or greater length is formed in the main interval 20m, which surrounds the balloon 2 in the circumferential z direction. The balloon 2 is contracted by the wing 29 being in close contact with the outer protrusion 60, thereby making the radius r0 smaller than at least one of the radii r1 and r2.

[0096] In the above configuration, the radius r3 of the third imaginary cylinder C3 circumscribed outside the main section 20m of the expansion portion 20 can be greater than, equal to, or smaller than, the radius r0 of the imaginary circle C0 circumscribed in the radial y section perpendicular to the major axis direction x at the midpoint 20c of the expansion portion 20 at the midpoint 20c of the major axis direction x. If at least one of the radius r1 of the first imaginary cylinder C1 circumscribed outside the proximal sleeve portion 21 and the radius r2 of the second imaginary cylinder C2 circumscribed outside the distal sleeve portion 22 is larger than the radius r0, then it is preferable that the radius r3 of the third imaginary cylinder C3 circumscribed outside the main section 20m is larger than the radius r0. Therefore, in the contracted state, the diameter of the central portion of the expansion portion 20 can be more suppressed at the proximal or distal end of the balloon 2, which is preferable from the viewpoints of improved tracking and protection of the expansion portion 20.

[0097] Preferably, the balloon 2 is folded in its contracted state. The balloon 2 can be folded in a folded state by hand or various folding machines before fluid is supplied to its interior or after fluid is discharged from its interior. In the folded state, the flaps 29 are securely folded around the axis 3 and do not float off the axis 3, thus preventing the flaps 29 from contacting the body cavity wall during delivery. This allows for easy reduction of the radius r0, making it more difficult for the expansion portion 20 to contact the body cavity wall, thereby improving the tracking ability of the balloon 2. Furthermore, the difficulty for the expansion portion 20 to contact the body cavity wall protects the expansion portion 20, which expands and acts on the lesion during treatment, from damage.

[0098] For example, it can be like Figure 14 and Figure 15 As shown, in the folded state of the balloon 2, the wing 29 is securely folded, and the outer protrusion 60 deforms in the circumferential z-direction of the wing 20. This folding makes it easier to reduce the radius r0. Examples of methods for folding the balloon 2 include using a hand, various folding machines, etc. By folding the balloon 2 in this way, the radius r0 can be adjusted regardless of the radial y-length of the outer protrusion 60, resulting in the ability to adjust the relationship between radius r0 and radii r1 and r2. That is, by deforming the outer protrusion 60 in the circumferential z-direction of the wing 29, the radius r0 can be reduced, making it smaller than at least one of radii r1 and r2.

[0099] Furthermore, the main section 20m is a section with a wing 29 of a certain length that surrounds the circumferential z direction. Therefore, if the main section 20m is folded in such a way that the outer protrusion 60 and the expansion portion 20 are deformed in the circumferential z direction of the wing 29, the radius r3 of the third imaginary cylinder C3 circumscribed outside the main section 20m can be easily reduced, and the radius r3 can be made smaller than at least one of the radii r1 and r2. As a result, it is difficult for the main section 20m to come into contact with the body cavity wall, and the contact area between the balloon 2 and the body cavity wall can be further reduced.

[0100] Preferably, the outer protrusion 60 has a front end 61 in a radial y section, satisfying at least one of (1) and (2) below when the balloon 2 is in a contracted state.

[0101] (1) The front end portion 61 is connected to at least a portion of the side of the first imaginary cylinder C1 outside the proximal sleeve portion 21.

[0102] (2) The front end portion 61 is connected to at least a portion of the side of the second imaginary cylinder C2 outside the distal sleeve portion 22.

[0103] By externally connecting the front end 61 to the imaginary cylinder, the area of ​​the sleeve portion connected to the imaginary cylinder can be reduced. The imaginary cylinder can also be considered as the body cavity wall when delivering the balloon 2 within the body cavity. By having the sleeve portion abut against the body cavity wall with a smaller contact area, the delivery path of the balloon 2 can be ensured, and the tracking performance of the balloon 2 can be improved. In this case, it is also possible to... Figure 11 As shown, only the front end 61 is externally connected to the imaginary cylinder, or it can be like... Figure 12 As shown, the front end 61 and the balloon body 27 are externally connected to an imaginary cylinder, or, although not shown, the front end 61 and other parts such as the outer protrusion 60 are externally connected to other parts such as the front end 61. Figure 11 and Figure 12 The proximal sleeve portion 21, which is externally connected to the first imaginary cylinder C1, is shown, but the distal sleeve portion 22, which is externally connected to the second imaginary cylinder C2, can also be referred to. Figure 11 and Figure 12 The same understanding applies.

[0104] Preferably, the outer protrusion 60 has a front end 61 in a radial y section, satisfying at least one of (1) and (2) below when the balloon 2 is in a contracted state.

[0105] (1) Only the front end portion 61 is connected to at least a portion of the side of the first imaginary cylinder C1 outside the proximal sleeve portion 21.

[0106] (2) Only the front end portion 61 is connected to at least a portion of the side of the second imaginary cylinder C2 outside the distal sleeve portion 22.

[0107] By attaching only the front end 61 to the imaginary cylinder, the area of ​​the sleeve portion attached to the imaginary cylinder can be further reduced. The imaginary cylinder can also be considered as the body cavity wall when delivering the balloon 2 within the body cavity. By having the sleeve portion abut against the body cavity wall with a smaller contact area, the delivery path of the balloon 2 can be ensured, and the tracking performance of the balloon 2 can be further improved. In this case, for example... Figure 11 As shown, the sleeve portion can be formed into a structure in which multiple outer protrusions 60 are separately arranged in the circumferential direction z. Figure 11 The proximal sleeve portion 21, which is externally connected to the first imaginary cylinder C1, is shown, but the distal sleeve portion 22, which is externally connected to the second imaginary cylinder C2, can also be referred to. Figure 11 The same understanding applies.

[0108] Preferably, in the contracted state of the balloon 2, the expansion portion 20 has a wing 29 and the wing 29 is externally circumscribed in an imaginary circle C0. Through Figure 7 and Figure 8 or Figure 9 and Figure 10 A comparison shows that by adjusting the diameter of the balloon body 27, the length of the wing 29 around the circumference z can be adjusted. However, by forming the wing 29 to a certain length or more, a structure is formed in which the wing 29 is circumscribed by an imaginary circle C0. This applies to structures such as... Figure 7 and Figure 10 The structure of the wing 29 circumscribed to the imaginary circle C0 makes it easy to protect the outer protrusion 60 from damage. Furthermore, when the balloon 2 is delivered into the body cavity, even if the expansion portion 20 is assumed to be in contact with the body cavity wall, the outer protrusion 60 acting on the lesion is unlikely to be in contact with the body cavity wall. Thus, it is possible to prevent the outer protrusion 60 from acting on the body cavity wall in an undesirable position.

[0109] exist Figures 7-10 The diagram shows a configuration with three winglets 29, but the number of winglets 29 is not particularly limited as long as the balloon 2 can be retracted. For example, two or more winglets are preferred, more preferably three, and four or more or five are also possible. Furthermore, the number of winglets 29 is preferably ten or fewer, more preferably eight or fewer, and even more preferably six or fewer. As long as the number of winglets 29 is within the above range, the balloon 2 can be easily retracted.

[0110] Preferably, in the contracted state of the balloon 2, the expansion portion 20 has a wing 29, and the outer protrusion 60 is disposed in a position other than the wing 29. If the outer protrusion 60 is disposed in a position other than the wing 29, the balloon 2 can be easily contracted because the outer protrusion 60 does not obstruct the wrapping of the wing 29. Furthermore, by disposing the outer protrusion 60 in a position other than the wing 29, it can be easily covered by the wing 29 in the contracted state of the balloon 2. Thus, it is easy to form a structure in which the wing 29 is circumscribed by an imaginary circle C0 in the contracted state of the balloon 2.

[0111] Next, refer to Figures 16-18 The balloon of the balloon catheter according to other embodiments of the present invention will be described. Figure 16 This is a side view showing the balloon of a balloon catheter according to another embodiment of the present invention in its contracted state. Figure 17 express Figure 16 The XVII-XVII sectional view, i.e., the radial sectional view of the distal sleeve portion. Figure 18 Indicates Figure 17 Another example of a sectional view shown.

[0112] like Figure 16 As shown, preferably, in the contracted state of the balloon 2, the radius r1 of the first imaginary cylinder C1 at the proximal sleeve portion 21 is larger than the radius r0 of the imaginary circle C0 at the expansion portion 20, and the radius r2 of the second imaginary cylinder C2 at the distal sleeve portion 22 is smaller than the radius r0 of the imaginary circle C0. By forming such a structure, the outer diameter of the distal sleeve portion 22, which becomes the anterior end side when inserted into the body cavity, can be suppressed, making the delivery of the balloon 2 within the body cavity easier. In addition, since the radius r1 is larger than the radius r0, when the balloon 2 is delivered within the body cavity, the proximal sleeve portion 21 abuts against the body cavity wall to support the body cavity wall on the proximal side of the balloon 2, thereby ensuring the delivery path of the balloon 2 and making it difficult for the expansion portion 20 to abut against the body cavity wall, thus improving the tracking ability of the balloon 2 and protecting the expansion portion 20. Thus, by forming the above structure, it is possible to form a balloon 2 that is easy to insert and has improved tracking performance, and the expansion portion 20 is easy to protect.

[0113] like Figure 17 As shown, the above structure can also be formed by shortening the radial y length of the outer protrusion 60 in the radial y section of the distal sleeve portion 22, or it can be formed by not providing the outer protrusion 60 in the distal sleeve portion 22. By shortening the radial y length of the outer protrusion 60 or not providing the outer protrusion 60, the radius r2 of the second imaginary cylinder C2 circumscribed outside the distal sleeve portion 22 can be reduced.

[0114] Alternatively, to reduce the radius r2, such as Figure 18As shown, preferably, the distal sleeve portion 22 has an inner protrusion 70, which protrudes radially inward (y) from the inner surface of the balloon body 27 and extends in the long axis direction (x). Alternatively, it can be as follows... Figure 18 As shown, an outer protrusion 60 with a shorter radial y-length is also provided in the radial y-section, or, although not shown, the outer protrusion 60 may not be provided. By providing the inner protrusion 70, even when the radial y-length of the outer protrusion 60 is short or the outer protrusion 60 is not provided, the strength of the balloon 2 can be improved and over-expansion of the balloon 2 during pressurization can be suppressed. When the outer protrusion 60 is provided together with the inner protrusion 70, it is preferable that the inner protrusion 70 and the outer protrusion 60 are located at the same position in the circumferential z-direction. This makes it easier to improve the strength of the balloon 2 and suppress over-expansion of the balloon 2 during pressurization.

[0115] like Figure 16 As shown, the preferred expansion section 20 has a main section 20m obtained by removing 10% of the long axis x from both the distal and proximal ends. In the contracted state of the balloon 2, the radius r1 of the first imaginary cylinder C1 in the proximal sleeve section 21 is larger than the radius r3 of the third imaginary cylinder C3, and the radius r2 of the second imaginary cylinder C2 in the distal sleeve section 22 is smaller than the radius r3 of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the long axis x, and the bottom surface of the third imaginary cylinder C3 is located at both the distal and proximal ends of the main section 20m. The main section 20m is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3. By forming such a structure, when the balloon 2 in a contracted state is delivered into the body cavity, the entire main section 20m of the expansion section 20 is unlikely to come into contact with the body cavity wall. In addition, it can suppress the outer diameter of the distal sleeve portion 22, which becomes the anterior end side, when inserted into the body cavity, making it easier to deliver the balloon 2 into the body cavity. The radius r1 is larger than the radius r3, so when the balloon 2 is delivered into the body cavity, the proximal sleeve portion 21 abuts against the body cavity wall to support the body cavity wall on the proximal side of the balloon 2. This ensures the delivery path of the balloon 2 and makes it difficult for the main section 20m of the expansion portion 20 to abut against the body cavity wall. As a result, the balloon 2 can be formed that is easy to insert, has better tracking performance, and is easier to protect the expansion portion 20.

[0116] Materials constituting the balloon body 27 include, for example, polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyester resins such as polyethylene terephthalate and polyester elastomers; polyurethane resins such as polyurethane and polyurethane elastomers; polyphenylene sulfide resins; polyamide resins such as polyamide elastomers; fluorinated resins; silicone resins; and natural rubber such as latex rubber. Only one type of these can be used, or two or more types can be used in combination. Polyamide resins, polyester resins, and polyurethane resins are particularly suitable. Especially considering the thin-film properties and flexibility of the balloon body 27, elastomer resins are preferred. For example, among polyamide resins, nylon 12 and nylon 11 are suitable as resins constituting the balloon body 27, and nylon 12 is more suitable considering its ease of molding during blow molding. Furthermore, considering the thin-film properties and flexibility of the balloon body 27, polyamide elastomers such as polyether ester amide elastomers and polyamide ether elastomers are preferred. Among these considerations, considering the high yield strength and good dimensional stability of the balloon body 27, polyether ester amide elastomer is preferred.

[0117] Preferably, the outer protrusion 60 is made of the same material as the balloon body 27. If the outer protrusion 60 is made of the same material as the balloon body 27, the flexibility of the balloon 2 can be maintained, and the outer protrusion 60 is less likely to damage the outer surface of the balloon body 27. Preferably, the balloon body 27 and the outer protrusion 60 are integrally formed. This prevents the outer protrusion 60 from detaching from the balloon body 27. In the configuration where the inner protrusion 70 is formed, the inner protrusion 70 is also preferably made of the same material as the balloon body 27 for the same reasons described above.

[0118] The balloon 2, for example, can transmit through a means such as Figure 19The cylindrical preform 200, made of resin, is manufactured by biaxial stretch blow molding, with a grooved inner cavity placed in a mold. The outer protrusion 60 can be formed, for example, by inserting the preform 200 into the inner cavity of the mold, causing the thick-walled portion 220 of the preform 200 to enter the groove of the mold, and by introducing fluid into the inner cavity 210 of the preform 200 to cause it to expand. The radial length y in the radial y section of the outer protrusion 60 can be adjusted by the thickness of the thick-walled portion 220 of the preform 200 and the depth of the groove in the mold. The inner protrusion 70 can be formed, for example, by pressing the thick-walled portion 220 of the preform 200 against the grooveless portion of the mold and introducing fluid into the inner cavity 210 of the preform 200 to cause it to expand. Furthermore, in order to form the outer protrusion 60 and inner protrusion 70 with short radial y-length in the radial y-section, for example, it can be formed by pressing the thick-walled portion 220 of the preform 200 against the shallow portion of the mold groove and introducing fluid into the inner cavity 210 of the preform 200 to expand the preform 200. As for the material constituting the preform 200, the description of the material constituting the above-described balloon body 27 can be referred to.

[0119] Examples of materials constituting the shaft 3 include polyamide resins, polyester resins, polyurethane resins, polyolefin resins, fluorinated resins, vinyl chloride resins, silicone resins, and natural rubber. Only one type may be used, or two or more may be used in combination. Preferably, the material constituting the shaft 3 is at least one of polyamide resin, polyolefin resin, and fluorinated resin. This improves the slipperiness of the shaft 3 surface, thereby enhancing the insertion success of the balloon catheter 1 within the body cavity.

[0120] For the joining of balloon 2 and shaft 3, methods such as bonding with adhesives, fusion bonding, and riveting by installing a ring-shaped component at the overlapping position of the end of balloon 2 and shaft 3 can be used. Among these, joining balloon 2 and shaft 3 by fusion bonding is preferred. By fusing balloon 2 and shaft 3, even if balloon 2 is repeatedly expanded and contracted, the joining of balloon 2 and shaft 3 is difficult to dislodge, and the joining strength of balloon 2 and shaft 3 can be easily improved.

[0121] like Figure 1 As shown, a hub 4 may be provided proximal to the shaft 3 in the balloon catheter 1, and a fluid injection section 7 communicating with the flow path of fluid supplied to the interior of the balloon 2 may be provided in the hub 4. Furthermore, the hub 4 preferably has a guidewire insertion section 5 communicating with the guidewire insertion path. By having a hub 4 with the fluid injection section 7 and the guidewire insertion section 5 in the balloon catheter 1, it is possible to easily supply fluid to the interior of the balloon 2 to inflate and deflate the balloon 2, and to deliver the balloon catheter 1 to the treatment site along the guidewire. The balloon 2 according to the embodiments of the present invention can be applied not only to… Figure 1The so-called OTW (Over-The-Wire) balloon catheter, which inserts the guidewire from the distal side to the proximal side of axis 3 as shown, can also be used as the so-called RX (RapidExchange) balloon catheter, which inserts the guidewire from the distal side of axis to the midway to reach the proximal side.

[0122] For the joining of shaft 3 and pivot 4, examples include bonding with adhesives and fusion bonding. Among these, it is preferable that shaft 3 and pivot 4 are joined by adhesive bonding. By bonding shaft 3 and pivot 4, for example, when the materials constituting shaft 3 and pivot 4 are different, such as shaft 3 being made of a highly flexible material and pivot 4 being made of a highly rigid material, the joining strength of shaft 3 and pivot 4 can be increased, thereby improving the durability of balloon catheter 1.

[0123] This application claims the benefit of priority based on Japanese Patent Application No. 2021-8307, filed January 21, 2021. The entire contents of the description of Japanese Patent Application No. 2021-8307, filed January 21, 2021, are incorporated herein by reference.

[0124] Explanation of reference numerals in the attached figures

[0125] 1...Balloon catheter; 2...Balloon; 3...Axis; 4...Pivot; 5...Guidewire insertion section; 7...Fluid injection section; 20...Dilation section; 20c...Midpoint of the long axis of the dilation section; 20m...Main section of the dilation section; 21...Proximal sleeve section; 22...Distal sleeve section; 27...Balloon body; 29...Flanges; 31...Lateral tube; 32...Medial tube; 60...Lateral protrusion; 61...Anterior end portion; 70...Medial protrusion; 200...Preform; 210... 220...the inner cavity of the preform; 220...the thick-walled portion of the preform; C0...an imaginary circle circumscribed at the midpoint of the expansion portion along its major axis; C1...a first imaginary cylinder circumscribed on the proximal sleeve portion; C2...a second imaginary cylinder circumscribed on the distal sleeve portion; C3...a third imaginary cylinder circumscribed on the main section of the expansion portion; r0...the radius of the imaginary circle C0; r1...the radius of the first imaginary cylinder C1; r2...the radius of the second imaginary cylinder C2; r3...the radius of the third imaginary cylinder C3; x...the major axis direction; y...the radial direction; z...the circumferential direction.

Claims

1. A balloon for a balloon catheter, comprising: an dilator; a proximal sleeve portion located closer to the dilator than the dilator; and a distal sleeve portion located distal to the dilator. The balloon used in the balloon catheter is characterized in that... It comprises: a balloon body having an outer surface and an inner surface; and a lateral protrusion that protrudes radially outward from the outer surface of the balloon body and extends along the long axis of the balloon body. The expansion portion has a main interval obtained by removing 10% of the length axis from both the distal and proximal ends. In the contracted state of the balloon, a flap is formed throughout the main compartment, but no flap is formed throughout the proximal sleeve portion and the distal sleeve portion. In the contracted state of the balloon, at least one of the following (1) and (2) is satisfied: (1) The radius of the first imaginary cylinder C1 is larger than the radius of the imaginary circle C0 and larger than the radius of the third imaginary cylinder C3. The first imaginary cylinder C1 has a central axis parallel to the major axis direction, and the first bottom surface and the second bottom surface of the first imaginary cylinder C1 are respectively located at the distal end and the proximal end of the proximal sleeve portion. The proximal sleeve portion is circumscribed on at least a portion of the side surface of the first imaginary cylinder C1. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the major axis direction at the midpoint of the expansion portion. The third imaginary cylinder C3 has a central axis parallel to the major axis direction, and the first bottom surface and the second bottom surface of the third imaginary cylinder C3 are respectively located at the distal end and the proximal end of the main interval. The main interval is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3. (2) The radius of the second imaginary cylinder C2 is larger than the radius of the imaginary circle C0 and larger than the radius of the third imaginary cylinder C3. The second imaginary cylinder C2 has a central axis parallel to the major axis direction, and the first bottom surface and the second bottom surface of the second imaginary cylinder C2 are respectively located at the distal end and the proximal end of the distal sleeve portion. The distal sleeve portion is circumscribed on at least a portion of the side surface of the second imaginary cylinder C2. The imaginary circle C0 is an imaginary circle circumscribed in a radial section perpendicular to the major axis direction at the midpoint of the expansion portion at the major axis direction. The third imaginary cylinder C3 has a central axis parallel to the major axis direction, and the first bottom surface and the second bottom surface of the third imaginary cylinder C3 are respectively located at the distal end and the proximal end of the main interval. The main interval is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3.

2. The balloon for balloon catheters according to claim 1, characterized in that, In the contracted state, the balloon is folded.

3. The balloon for balloon catheters according to claim 1 or 2, characterized in that, The outer protrusion has a front end in the radial section, and satisfies at least one of (1) and (2) below in the contracted state of the balloon. (1) The front end portion is at least a portion of the side surface of the first imaginary cylinder C1 outside the proximal sleeve portion. (2) The front end portion is connected to at least a portion of the side surface of the second imaginary cylinder C2 outside the distal sleeve portion.

4. The balloon for balloon catheters according to claim 1 or 2, characterized in that, The outer protrusion has a front end in the radial section, and satisfies at least one of (1) and (2) below in the contracted state of the balloon. (1) Only a portion of the front end portion is connected to the side surface of the first imaginary cylinder C1 outside the proximal sleeve portion. (2) Only the front end portion is connected to at least a portion of the side of the second imaginary cylinder C2 outside the distal sleeve portion.

5. The balloon for balloon catheters according to claim 1 or 2, characterized in that, In the contracted state of the balloon, the expansion portion has winglets that are externally circumscribed in the imaginary circle C0.

6. The balloon for balloon catheters according to claim 1 or 2, characterized in that, In the contracted state of the balloon, the expansion portion has winglets, and the outer protrusion is positioned in a location other than the winglets.

7. The balloon for balloon catheters according to claim 1 or 2, characterized in that, Satisfying at least one of (1) and (2) below, (1) The outer protrusion of the proximal sleeve portion and the outer protrusion of the expansion portion extend continuously in the long axis direction. (2) The outer protrusion of the distal sleeve portion and the outer protrusion of the expansion portion extend continuously in the long axis direction.

8. The balloon for balloon catheters according to claim 1 or 2, characterized in that, In the contracted state of the balloon, the radius of the first imaginary cylinder C1 at the proximal sleeve portion is larger than the radius of the imaginary circle C0 at the expansion portion, and the radius of the second imaginary cylinder C2 at the distal sleeve portion is smaller than the radius of the imaginary circle C0.

9. The balloon for balloon catheters according to claim 8, characterized in that, The expansion portion has a main interval obtained by removing 10% of the long axis direction from both the distal and proximal ends. In the contracted state of the balloon, the radius of the first imaginary cylinder C1 at the proximal sleeve portion is larger than the radius of the third imaginary cylinder C3, and the radius of the second imaginary cylinder C2 at the distal sleeve portion is smaller than the radius of the third imaginary cylinder C3. The third imaginary cylinder C3 has a central axis parallel to the long axis direction, and the bottom surface of the third imaginary cylinder C3 is located at the distal and proximal ends of the main interval. The main interval is circumscribed on at least a portion of the side surface of the third imaginary cylinder C3.

10. The balloon for balloon catheters according to claim 8, characterized in that, The distal sleeve portion has an inner protrusion that protrudes radially inward beyond the inner surface of the balloon body and extends along the long axis.

11. The balloon for balloon catheters according to claim 1 or 2, characterized in that, The outer protrusion is made of the same material as the balloon body.

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