JP2013022347A - Method for manufacturing balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an appropriate manufacturing method in manufacturing a balloon catheter, capable of suppressing such inconvenience that an inflated part of a balloon is unintentionally brought into contact with a normal region inside the body.SOLUTION: The balloon catheter includes a catheter tube 11, which includes an outer tube 15 and an inner tube 16. The balloon 13 is provided to cover a portion of the inner tube 16 projecting on the distal side from the outer tube 15, and a contrast ring 30 is attached to a region in the inner tube 16 covered by the balloon 13. The method for manufacturing the catheter includes: a step of attaching the contrast ring 30 to the inner tube 16; and a step of positioning the balloon 13 to the inner tube 16 so as not be displaced to the proximal side from a proximal contrast ring 30b while the maximum pressure is applied to the proximal end of a straight tube region 13c of the balloon 13, and jointing the balloon 13 in the positioned state to the inner tube 16.

Description

  The present invention relates to a method for manufacturing a balloon catheter that is used by being introduced into a living body when, for example, an expansion treatment is performed on a stenosis or occlusion in a blood vessel.

  Conventionally, balloon catheters have been used in treatments such as PTA (percutaneous angioplasty) and PTCA (percutaneous coronary angioplasty) (see, for example, Patent Document 1). The balloon catheter includes a catheter tube and a balloon provided on the distal end side of the catheter tube. The balloon catheter is introduced and inflated by introducing the balloon into a portion that is narrowed or occluded by a lesioned portion or the like generated in the blood vessel. , The part is expanded.

  In general, when a balloon catheter is introduced into the body, it is performed while confirming the position of the balloon with a contrast ring (X-ray opaque marker) provided at the distal end of the catheter. FIG. 10 is a cross-sectional view showing an example of a balloon catheter to which such a contrast ring is attached. FIG. 10 shows the state of the balloon when a predetermined reference pressure (nominal pressure) is applied. The right side of the figure is the distal side, and the left side of the figure is the proximal side. As shown in FIG. 10, the balloon catheter 80 includes a catheter tube 81 and a balloon 82, and the catheter tube 81 includes an outer tube 83 and an inner tube 84 inserted into the outer tube 83. Yes. The inner tube 84 is provided in a state where a part of the inner tube 84 extends more distally than the outer tube 83, and a balloon 82 is provided so as to cover the extended region from the outside.

  The balloon 82 has joint portions at both ends joined to the catheter tube 81 and an inflating portion therebetween. Specifically, the balloon 82 includes a proximal leg region 82a joined to the outer tube 83 and a proximal cone region tapered so that the inner diameter and the outer diameter increase toward the distal end side. 82b, the straight tube region 82c having the same inner diameter and outer diameter in the entire length direction and forming the maximum outer diameter region of the balloon 82, and the inner diameter and the outer diameter are reduced toward the distal end side. Thus, the distal-side cone region 82d that is tapered and the distal-side leg region 82e joined to the inner tube 84 are provided in this order from the proximal side.

  Two contrast rings 90 are attached to the area of the inner tube 84 covered by the balloon 82. As shown in FIG. 10, each contrast ring 90 is provided at a position corresponding to both ends of the straight tube region 82c in the axial direction of the inner tube 84 in a state where a predetermined reference pressure is applied. Specifically, the distal end of the distal contrast ring 90a is in the same position as the distal end of the straight tube region 82c, and the proximal end of the proximal contrast ring 90b is straight. It arrange | positions so that it may become the same position as the proximal end part of the pipe | tube area | region 82c.

  Here, when the lesion site in the blood vessel is expanded using the balloon catheter 80 having the above configuration, the balloon 82 is first introduced into the lesion site in a deflated state. In this case, the position of the balloon 82 is adjusted so that the straight tube region 82c is at a position facing the lesioned part while confirming the position of the contrast unit 90 in a fluoroscopic state. This position adjustment is performed, for example, by aligning the proximal end portion of the proximal contrast ring 90b with the proximal end portion of the lesion site. Thereafter, a predetermined pressure, for example, a nominal pressure (specified pressure) is applied to the balloon 82 to inflate the balloon 82 to expand the lesion. Thereby, the proximal end part of the expanded straight tube | pipe area | region 82c becomes the same position as the proximal end part of a lesioned part.

JP 2008-237844 A

  By the way, when the lesioned part to be expanded by the balloon 82 is hardened by calcification or the like, the lesioned part may not be sufficiently expanded even if the balloon 82 is expanded under a nominal pressure. sell. In that case, by applying a pressure higher than the nominal pressure to the balloon 82, the balloon 82 is inflated and the lesioned part is expanded.

  However, when a pressure higher than the nominal pressure is applied to the balloon 82, it is assumed that the straight tube region 82c extends in the axial direction. In that case, there is a possibility that the proximal end side of the straight tube region 82c reaches a normal part other than the partially affected part, and the straight tube region 82c unintentionally contacts the blood vessel wall in the normal part. In this respect, it can be said that the conventional balloon catheter still has room for improvement.

  The present invention has been made in view of the above circumstances, and provides a manufacturing method suitable for manufacturing a balloon catheter that can suppress inconvenience of an inflated portion of a balloon unintentionally coming into contact with a normal site in the body. Is the main purpose.

  In order to solve the above problems, a method for manufacturing a balloon catheter according to a first aspect of the present invention includes a tubular outer shaft, and a portion extending to the distal side of the outer shaft. The inserted inner shaft and the extended portion of the inner shaft are provided so as to cover from the outside, and one end portion is joined to the distal end portion of the outer shaft and the other end portion is formed on the inner shaft. A balloon joined to the extension portion, and a contrast section attached to a region covered with the balloon on the inner shaft, and the balloon is supplied with a fluid therein and has a predetermined range defined in advance. It expands when the internal pressure is applied, and contracts when the fluid is discharged. Applied to a balloon catheter having an inflatable effective region, the contrast portion attaching step for attaching the contrast portion to the inner shaft, and by applying the pressure in both end portions in the axial direction of the inner shaft in the inflatable effective region of the balloon The balloon is connected to the inner shaft so that the displacement end portion that is displaced in the axial direction is not displaced more than the contrast portion toward the displacement side in a state where the maximum pressure within the predetermined range is applied. And a balloon bonding step of bonding the balloon to the inner shaft in the positioned state.

  According to the manufacturing method of the present invention, the operation of attaching the contrast section to the inner shaft and positioning and joining the balloon to the inner shaft are performed in a state where the maximum pressure is applied to the balloon when the balloon catheter is used, that is, The expansion can be carried out in consideration of the maximum extension state in which the extension in the axial direction of the effective expansion region is maximized.

  Further, according to the balloon catheter manufactured by the manufacturing method of the present invention, even when the maximum pressure is applied to the balloon and the length (extension) of the expansion effective region in the axial direction becomes the maximum, the effective expansion region Is not displaced beyond the contrast portion on the displacement side. Therefore, when the balloon is introduced into the lesioned part in the body and placed, for example, if the end near the balloon end in the contrast part is aligned with the end of the lesioned part, the pressure applied to the balloon is small or large. Regardless of (but limited to a pressure within a predetermined range), it is possible to suppress the expansion effective region from reaching a site other than the lesion, that is, a normal site. As a result, it is possible to suppress the inconvenience that the balloon inflating effective region unintentionally contacts a normal part in the body.

  In the balloon catheter manufacturing method according to a second aspect of the present invention, in the first aspect of the invention, in the balloon joining step, a position that becomes an end portion of the contrast portion in the axial direction of the inner shaft is applied when the maximum pressure is applied. The balloon is positioned and joined to the inner shaft so as to be in the same position as the end of the effective region.

  According to the present invention, when the maximum pressure is applied to the balloon, the end of the contrast portion and the displacement end of the expansion effective region are in the same position. Therefore, when the balloon is placed in a state where the end of the contrast portion and the end of the lesion are aligned with the lesion in the body, if the balloon is subjected to maximum pressure, the displacement of the inflatable effective region is displaced. The end and the end of the lesion are in the same position, so that the lesion can be expanded to reach that end. On the other hand, if a pressure lower than the maximum pressure is applied to the balloon, for example, a reference pressure (specifically, a pressure when the outer diameter of the expansion effective region becomes a predetermined outer diameter defined in advance), the balloon is inflated Since the displacement amount of the displacement end portion of the effective region is smaller than that when the maximum pressure is applied, a part of the end portion side in the lesion portion becomes an unexpanded region that is not expanded. Can be relatively reduced. Therefore, in this case, the lesioned part can be suitably expanded while obtaining the effect of the first invention.

  According to a third aspect of the present invention, there is provided a balloon catheter manufacturing method according to the second aspect of the invention, wherein the expansion effective region is inflated so that the outer diameter of the effective expansion region becomes a prescribed outer diameter defined in advance for the pressure within the predetermined range. A reference pressure to be included, and the contrast portion has a length in the axial direction, and a displacement end portion of the effective expansion region when the pressure applied to the balloon increases from the reference pressure to the maximum pressure. Has the same length as the displacement amount, and in the balloon joining step, one end portion of the contrast portion is located at the same position as the displacement end portion of the expansion effective region in the axial direction when the reference pressure is applied. The balloon is positioned and joined to the inner shaft so that the other end of the contrast portion is located at the same position as the displacement end of the expansion effective region when the maximum pressure is applied. .

  According to the present invention, when expanding a lesioned part by applying a reference pressure to the balloon, the balloon is arranged with the one end of the contrast unit and the end of the lesioned part aligned with respect to the lesioned part. As a result, the lesioned part can be expanded to the end thereof. Also, when expanding the lesion by applying the maximum pressure to the balloon, the balloon is positioned by aligning the other end of the contrast unit and the end of the lesion with respect to the lesion. The lesion can be expanded to its end. Therefore, in this case, the lesion can be suitably expanded regardless of whether the reference pressure or the maximum pressure is applied to the balloon.

  In the method for manufacturing a balloon catheter according to a fourth aspect of the present invention, in any one of the first to third aspects of the invention, the outer diameter of the effective expansion region is a predetermined outer diameter defined in advance for the pressure in the predetermined range. Reference pressure for expanding the expansion effective region is included, one of the two end portions in the expansion effective region is the displacement end, and the other is a non-displacement end that does not displace in the axial direction. A first contrast portion provided corresponding to the displacement end portion as the contrast portion and a second contrast portion provided corresponding to the non-displacement end portion are attached to the inner shaft apart from each other. In the contrast part attaching step, the first contrast part is opposite to the second contrast part, and the second contrast part is opposite to the first contrast part. The distance from the end of the The first contrast portion and the second contrast portion are each attached to the inner shaft so as to be equal to or longer than the axial length of the effective expansion region when a large pressure is applied. In the balloon joining step, In the direction, the displacement end is not displaced more than the first contrast unit on the displacement side of the displacement end when the maximum pressure is applied, and the non-displacement end is The balloon is positioned and joined to the inner shaft so as to be positioned within the length range of the second contrast section at the time of reference pressure.

  According to the present invention, the displacement end portion which is one end portion of both end portions of the balloon inflatable effective region is not displaced beyond the first contrast portion when the maximum pressure is applied. Yes. Further, the non-displacement end, which is the other end, is positioned within the length range of the second contrast unit when the reference pressure is applied, and therefore is positioned within the same length range when the maximum pressure is applied. Is done. Therefore, in this case, it is possible to suppress the inconvenience that the effective area comes into contact with a normal part in the body at both ends of the expansion effective area.

  According to a fifth aspect of the present invention, there is provided a method for manufacturing a balloon catheter according to any one of the first to fourth aspects of the present invention, wherein a joint reference portion serving as a reference position for balloon joint is defined on the inner shaft, and a displacement end portion of the inflation effective region is When the maximum pressure is applied, a position of the contrast portion that is prevented from being displaced more than the contrast portion on the displacing side is obtained in advance as a distance from the joining reference portion, and in the contrast portion attaching step, the joining portion The contrast portion is positioned and attached to the inner shaft based on the distance from the reference portion, and the balloon is positioned relative to the inner shaft based on the distance from the reference portion in the balloon joining step. And joining.

  By the way, in order to prevent the displacement end portion of the balloon inflating effective region from being displaced from the contrasting portion to the displacing side of the displacement end portion when the maximum pressure is applied, the displacement end portion of the inflating effective region in the balloon joining process. It is conceivable to perform the work while visually confirming the positional relationship between the image and the contrast unit. However, since the contrast portion is disposed in a region covered with the balloon on the inner shaft, it is considered that the position of the contrast portion may be difficult to visually recognize from the outside of the balloon. In the present invention, in view of this point, the contrast portion is attached to the inner shaft with reference to the joining reference portion of the inner shaft, and the balloon is joined to the inner shaft using the joining reference portion of the inner shaft as a reference. In this case, since the balloon can be attached to the desired position with respect to the inner shaft without checking the position of the contrast portion, the workability can be improved and the positioning accuracy of the balloon is ensured. it can.

1 is a schematic overall side view of a balloon catheter. The side view of a balloon and its periphery. It is a side view which shows the structure of a balloon periphery, (a) shows the case where a nominal pressure is provided to a balloon, (b) shows the case where RB pressure is provided. Explanatory drawing for demonstrating the manufacturing procedure of a balloon catheter. Explanatory drawing for demonstrating the use procedure of a balloon catheter. Explanatory drawing for demonstrating the use procedure of a balloon catheter. Explanatory drawing for demonstrating another example regarding the attachment position of a proximal contrast ring. The side view which shows the structure of another balloon periphery. The side view which shows the structure of another balloon periphery. Sectional drawing which shows the structure of the balloon periphery of the conventional balloon catheter.

  Hereinafter, an embodiment of a balloon catheter will be described with reference to the drawings. First, a schematic configuration of the balloon catheter 10 will be described with reference to FIG. FIG. 1 is a schematic overall side view showing the configuration of the balloon catheter 10.

  As shown in FIG. 1, the balloon catheter 10 includes a catheter tube 11, a hub 12 attached to a proximal end portion (base end portion) of the catheter tube 11, and a distal end side (tip side) of the catheter tube 11. ) Attached to the balloon 13.

  The catheter tube 11 is composed of a plurality of tubes, and has an inner and outer multi-tube structure from at least an intermediate position in the axial direction (longitudinal direction) to the position of the balloon 13. Specifically, the catheter tube 11 includes an outer tube 15 and an inner tube 16 having an inner diameter and an outer diameter smaller than the outer tube 15, and the inner tube 16 is inserted into the outer tube 15. Thus, it has an inner and outer double pipe structure. Here, the outer tube 15 corresponds to the outer shaft, and the inner tube 16 corresponds to the inner shaft.

  The outer tube 15 is formed in a tubular shape having outer tube holes 21 (see FIG. 2) that are continuous over the entire axial direction and open at both ends. The outer tube 15 includes an outer proximal tube 22 that forms a predetermined range from a position continuous with the hub 12 toward the distal side, and an outer distal tube 23 that forms a distal side. The outer proximal tube 22 is made of a metal such as a Ni—Ti alloy or stainless steel, and the outer distal tube 23 is made of a thermoplastic polyamide so as to be less rigid than the outer proximal tube 22. Yes. The outer proximal tube 22 may be made of a synthetic resin. Further, the material for forming the outer distal tube 23 is not limited to thermoplastic polyamide, and may be other thermoplastic resin.

  The inner tube 16 is formed in a tubular shape having inner tube holes 31 (see FIG. 2) that are continuous over the entire axial direction and open at both ends. The inner tube 16 has a proximal end joined to an intermediate position in the axial direction of the outer tube 15, specifically, a boundary between the outer proximal tube 22 and the outer distal tube 23. Further, the inner tube 16 is provided in a state where a part thereof extends to the distal side of the outer tube 15, and the balloon 13 is provided so as to cover the extended region from the outside. Yes.

  The outer tube hole 21 of the outer tube 15 functions as a fluid lumen through which the compressed fluid flows when the balloon 13 is inflated or deflated. The inner tube hole 31 of the inner tube 16 functions as a guide wire lumen through which the guide wire G is inserted. Further, the proximal end opening 31a of the inner tube hole 31 is present at a midway position in the axial direction of the balloon catheter 10. Therefore, the balloon catheter 10 is configured as a so-called RX type catheter. However, the present invention is not limited to this, and a so-called over-the-wire type catheter in which the proximal end opening 31a of the inner tube hole 31 is present at the proximal end portion of the balloon catheter 10 may be used.

  Next, the configuration of the balloon 13 and its surroundings will be described with reference to FIG. FIG. 2 is a side view of the balloon 13 and its surroundings showing the balloon 13 and the outer tube 15 in a longitudinal cross-sectional state. In FIG. 2, the balloon 13 is shown in an inflated state. More specifically, FIG. 2 shows a state in which a predetermined nominal pressure (specified pressure) is applied to the inside of the balloon 13 and inflated. Here, the nominal pressure is a pressure applied to inflate the balloon 13 so that the outer diameter of the straight pipe region 13c described later becomes a predetermined outer diameter (effective diameter). In this embodiment, This nominal pressure is set to 0.6 MPa (6 atm). Here, the nominal pressure corresponds to the reference pressure.

  As described above, the balloon 13 is provided so as to cover a region extending from the outer side of the inner tube 16 to the distal side of the outer tube 15 (hereinafter, this region is referred to as an extending region 18). In this state, the proximal end is joined to the distal end of the outer tube 15 (specifically, the outer distal tube 23), and the distal end is the distal end of the inner tube 16 (specifically, the extension region 18). It is joined to the side.

  The balloon 13 is made of a thermoplastic polyamide elastomer. However, it is not limited to polyamide elastomer as long as it can expand and contract well with fluid supply and discharge, and other thermoplastic resins may be used, such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, Polyamide, polyimide, polyimide elastomer, silicon rubber, etc. can also be used. Moreover, the compound for exhibiting a desired function and another polymer may be added with respect to the said thermoplastic resin.

  The balloon 13 has joint portions at both ends joined to the catheter tube 11 and an inflating portion between the joint portions. More specifically, the balloon 13 has a proximal leg region 13a joined to the distal end portion of the outer tube 15 (outer distal tube 23), and an inner diameter and an outer diameter continuously toward the tip side. A proximal cone region 13b that is tapered so as to be expanded in diameter, a straight tube region 13c that has the same inner diameter and outer diameter in the entire length direction and forms the maximum outer diameter region of the balloon 13, and a tip A distal cone region 13d having a tapered shape so that the inner diameter and the outer diameter are continuously reduced toward the side, and a distal leg region 13e joined to the extension region 18 of the inner tube 16 , In this order from the proximal side. The joining of the outer tube 15 and the proximal leg region 13a and the joining of the inner tube 16 and the distal leg region 13e are both performed by thermal welding. However, these bondings are not necessarily performed by heat welding, and may be performed using an adhesive or the like. Here, the straight pipe region 30c corresponds to the effective expansion region.

  The balloon 13 is in an inflated state when the compressed fluid is supplied into the balloon 13 through the outer tube hole 21 of the outer tube 15, and a negative pressure is applied to the outer tube hole 21, so that the compressed fluid is discharged from the balloon 13. When discharged, it is in a contracted state. The balloon 13 is formed into a plurality of wings (specifically, three wings) having a plurality of wings in the circumferential direction, and the balloon 13 is inflated and expanded so that a plurality of wings are formed in the contracted state. The contraction region is folded, and the plurality of wings are wound around the inner tube 16 around the axis.

  Here, the dimension of the balloon 13 in the inflated state, more specifically, the dimension (specified dimension) of the balloon 13 when the nominal pressure is applied will be described. The outer diameter dimension D of the straight tube region 13c is 3 mm, and the length in the axial direction AL is set to 10 mm. The sum of the length in the axial direction of the distal cone region 13d and the length in the axial direction of the distal leg region 13e (hereinafter referred to as the distal cone leg length BL) is set to 8 mm. The axial length of the distal cone region 13d is longer than the axial length of the proximal cone region 13b, but the axial length of the distal cone region 13d is proximal. The cone region 13b may be shorter than the length in the axial direction, or the cone regions 13b and 13d may have the same length.

  Further, a part of the inner tube 16 extends further to the distal side than the distal leg region 13e (the distal end thereof) of the balloon 13, and the distal end side thereof is tapered. The length (CL) in the axial direction of the extended portion (hereinafter referred to as the extended portion 16a) of the inner tube 16 is set to 3 mm.

  Two contrast rings 30 are attached to the outer peripheral surface of the inner tube 16 in the region covered from the outside by the balloon 13. The contrast ring 30 is intended to improve the visibility of the balloon 13 under X-ray projection and to easily align the balloon 13 with the target treatment site, and corresponds to a contrast unit. The contrast ring 30 is formed in a cylindrical shape (annular shape) from stainless steel. The contrast ring 30 has a predetermined length XL in the axial direction thereof, and the length XL is set to 1 mm in the present embodiment. The contrast ring 30 is not necessarily formed of stainless steel, and may be formed using other metal materials such as gold, platinum, iridium, cobalt chrome alloy, titanium, and the like, as long as it performs a contrast function. It may be made of resin.

  The two contrast rings 30 are provided apart from each other in the inner tube 16. Specifically, the two contrast rings 30 are respectively provided corresponding to the distal end portion and the proximal end portion of the straight tube region 13c of the balloon 13, and are provided at the distal end portion of the straight tube region 13c. The contrast ring 30 provided corresponding to the distal contrast ring 30a and the contrast ring 30 provided corresponding to the proximal end of the straight tube region 13c are the proximal contrast ring 30b. Here, the distal contrast ring 30a corresponds to the second contrast section, and the proximal contrast ring 30b corresponds to the first contrast section.

  By the way, as described above, the balloon 13 is basically inflated by applying a nominal pressure, and its outer diameter becomes an effective diameter. However, when the catheter is used, the balloon 13 is inflated by applying a pressure higher than the nominal pressure. Sometimes. In that case, it is considered that the straight tube region 13c of the balloon 13 extends in the axial direction, and the length AL in the axial direction becomes longer than the specified dimension (10 mm). Therefore, in the present embodiment, the attachment position of each contrast ring 30 is determined in consideration of the extension of the straight tube region 30c in the axial direction. In the following, FIG. It explains using. FIG. 3 is a side view showing a configuration around the balloon 13, where (a) applies a nominal pressure to the balloon 13, and (b) applies an RB pressure (rated breaking pressure) to the balloon 13. Is shown. FIG. 3A shows the same state as FIG. Here, the RB pressure is the maximum value within a predetermined pressure range applied to the balloon 13 when the balloon 13 is inflated. In this embodiment, the RB pressure is 1.4 MPa (14 atm). Is set to Here, the RB pressure corresponds to the maximum pressure.

  First, prior to the description of the attachment position of the contrast ring 30, how the straight tube region 13c extends in the axial direction when the pressure applied to the balloon 13 increases from the nominal pressure to the RB pressure. Will be described.

  As shown in FIG. 3A, when a nominal pressure is applied to the balloon 13, the axial length AL of the straight tube region 13c is 10 mm (specified length) as described above. Hereinafter, the length AL of the straight pipe region 13c in such a case is referred to as AL1 (= 10 mm). On the other hand, as shown in FIG. 3B, when the RB pressure is applied to the balloon 13, the straight tube region 13c extends in the axial direction as compared with the case of applying the nominal pressure, and the axial direction of the region 13c Is longer than AL1. For example, AL is 11 mm. Hereinafter, the length AL of the straight pipe region 13c in such a case is referred to as AL2 (= 11 mm) (that is, AL2> AL1). As described above, the straight tube region 13c extends in the axial direction when the pressure applied to the balloon 13 increases from the nominal pressure to the RB pressure. In the following description, this amount of expansion is expressed as W (= 1 mm). That's it. In this embodiment, as described above, since the length XL in the axial direction of the contrast ring 30 is 1 mm, the extension amount W and the length XL of the contrast ring 30 have the same value. ing.

  The elongation amount W varies depending on the size of the balloon 13 (specifically, the outer diameter D and the axial length AL) and the pressure application range defined in advance. The larger the balloon size, and the larger the value of the RB pressure applied to the balloon 13, the larger the balloon size.

  Further, at the time of nominal pressure and at the time of RB pressure, the position of the distal end portion of the straight tube region 13c with respect to the inner tube 16, in other words, the position of the boundary portion between the straight tube region 13c and the distal cone region 13d is axial. Has not changed. On the other hand, the position of the proximal end portion of the straight tube region 13c with respect to the inner tube 16, in other words, the position of the boundary portion between the straight tube region 13c and the proximal cone region 13b is more in the RB pressure than in the nominal pressure. Is proximal in the axial direction. Specifically, it is on the proximal side by the amount of extension W of the straight pipe region 13c. Therefore, it can be said that the straight tube region 13c at the time of RB pressure does not extend to the distal side but only to the proximal side with respect to the straight tube region 13c at the time of nominal pressure. This is because the distal end or distal leg region 13 e of the balloon 13 is joined to the inner tube 16, whereas the proximal end or proximal leg region 13 a of the balloon 13 is joined to the inner tube 16. It can be said that this is because it is not joined. That is, in the configuration in which the balloon 13 is joined to the inner tube 16 only on the distal end side in this way, the displacement in the axial direction is restricted at the distal end portion of the straight tube region 13c close to the joined portion. On the other hand, it is considered that the displacement in the axial direction of the proximal end portion of the straight pipe region 13c that is relatively separated from the joint portion is not regulated or is less regulated. It is done. Note that the displacement of the proximal end portion of the straight tube region 13c (in other words, the amount of extension of the straight tube region 13c) is absorbed by the deformation (contraction, deflection, etc.) of the outer tube 15. Here, the proximal end portion of the straight tube region 13c corresponds to a displacement end portion, and the distal end portion of the straight tube region 13c corresponds to a non-displacement end portion.

  In addition, although illustration is abbreviate | omitted about the expansion | swelling state of the balloon 13 in case the pressure higher than nominal pressure and lower than RB pressure is provided with respect to the balloon 13, in this pressure range, the straight pipe | tube area | region 13c of the balloon 13 is not shown. The length AL increases in proportion to the pressure applied to the balloon 13.

  Next, the attachment position of the contrast ring 30 with respect to the inner tube 16 will be described. First, the attachment position of the distal contrast ring 30a will be described. As shown in FIG. 3A, the distal contrast ring 30a has a distal end portion in the straight tube region 13c in the axial direction of the inner tube 16 when a nominal pressure is applied to the balloon 13. It is arranged and attached to the inner tube 16 so as to be in the same position as the distal end portion. Further, as described above, in the present balloon 13, the position of the distal end portion of the straight tube region 13c does not change in the axial direction between the nominal pressure and the RB pressure, so as shown in FIG. Even at the time of RB pressure, the distal end of the distal contrast ring 30a is located at the same position as the distal end of the straight tube region 13c.

  On the other hand, as shown in FIG. 3A, the proximal contrast ring 30b has the distal end located at the same position as the proximal end of the straight tube region 13c in the axial direction at the time of nominal pressure. Is arranged and attached to the inner tube 16. Further, as described above, the amount of extension W in the axial direction of the straight tube region 13c (in other words, the amount of displacement toward the proximal side of the proximal end of the straight tube region 13c) and the length of the contrast ring 30 in the axial direction. Since the height XL is the same value, as shown in FIG. 3B, the proximal contrast ring 30b has a proximal end portion that is the same as the proximal end portion of the straight tube region 13c at the time of RB pressure. The same position in the axial direction.

  That is, at the time of RB pressure, the distal end of the distal contrast ring 30a is in the same position as the distal end of the straight tube region 13c, and the proximal end of the proximal contrast ring 30b is at the same position. It is in the same position as the proximal end of the straight tube region 13c. Accordingly, the distance MX from the distal end of the distal contrast ring 30a to the proximal end of the proximal contrast ring 30b is the same as the axial length AL2 of the straight tube region 13c at the time of RB pressure. (MX = AL2). That is, MX is set to 11 mm.

  Next, the manufacturing procedure of the balloon catheter 10 will be described with reference to FIG. FIG. 4 is an explanatory diagram for explaining a manufacturing procedure of the balloon catheter 10.

  First, as shown in FIG. 4A, a contrast ring attaching step for attaching the contrast rings 30a and 30b to the inner tube 16 is performed. In this step, first, the distal contrast ring 30a is aligned with the distal end of the distal contrast ring 30a from the distal end of the inner tube 16 (corresponding to the joining reference portion) by a dimension X, and the contrast contrast ring 30a. 30 a is attached to the inner tube 16. Here, the dimension X corresponds to the sum of the extension length CL of the extension portion 16 a of the inner tube 16 and the distal cone leg length BL of the balloon 13. As described above, in the present balloon 13, since CL is set to 3 mm and BL is set to 8 mm, X is 11 mm.

  Next, the proximal contrast ring 30 b is attached to the inner tube 16 with its proximal end aligned with the position proximal to the dimension Y from the distal end of the inner tube 16. Here, the dimension Y corresponds to the sum of the dimension X and the axial length AL2 of the straight pipe region 13c at the time of RB pressure. As described above, in the present balloon 13, since X is 11 mm and AL2 is 11 mm, Y is 22 mm.

  Here, AL2 differs depending on the balloon size such as the outer diameter D of the straight tube region 13c and the axial length AL (or the axial length of the balloon 13) at the nominal pressure, and the RB pressure. In association with these balloon sizes and RB pressures, a plurality of AL2 values are determined in advance for each type of balloon catheter. In this case, the relationship between the size of the balloon size or RB pressure and the value of AL2 is defined in advance as work data. Based on the work data, the operator can determine the AL2 of the type of balloon catheter in the manufacturing process. Will be obtained. That is, in the case of this embodiment, since the outer diameter D of the straight pipe region 13c is 3 mm, the axial length AL is 10 mm, and the RB pressure is 1.4 MPa, AL2 is obtained from the working data based on these values. Is required to be 11 mm. In addition, by using this working data, the manufacturing method of the present invention can be applied to a plurality of types of balloon catheters having different balloon sizes and RB pressures.

  Further, in this contrast ring attaching step, the order of attaching the contrast rings 30a and 30b to the inner tube 16 may be arbitrary, so the proximal contrast ring 30b is attached first and the distal contrast ring 30a is attached to the inner tube 16 later. May be.

  Next, as shown in FIG. 4B, a balloon proximal side joining step for joining the proximal end portion of the balloon 13 to the distal end portion of the outer distal tube 23 is performed. In this step, the proximal leg region 13a of the balloon 13 is set to the outside and the distal end portion of the outer distal tube 23 is set to the inside, and both of them are overlapped, and both of them are joined by heat welding in the overlapped state. Note that the joining method is not necessarily limited to thermal welding, and other joining methods such as adhesion with an adhesive may be employed.

  Next, as shown in FIG. 4C, a balloon positioning step is performed in which the balloon 13 joined to the outer distal tube 23 is positioned at a predetermined position in the axial direction with respect to the inner tube 16. In this step, the inner tube 16 is inserted into the outer tube hole 21 of the outer distal tube 23 and the inside of the balloon 13, and a part of the tube 16 is extended to the distal side of the balloon 13 by a predetermined length. Specifically, a part of the inner tube 16 is extended from the balloon 13 (the distal end thereof) by the extension length CL (= 3 mm) of the extension portion 16a. Thereby, the balloon 13 is positioned at a predetermined position in the axial direction with respect to the inner tube 16.

  In this step, a predetermined pressure (for example, nominal pressure) is applied to the balloon 13 and the operation is performed with the balloon 13 inflated. Further, in the subsequent balloon distal side joining step, the operation is continuously performed with the balloon 13 inflated. However, the operation may be performed in a state where the balloon 13 is deflated in at least one of the present step and the subsequent balloon distal side joining step.

  Next, a balloon distal side joining step of joining the distal end portion of the balloon 13 positioned by the balloon positioning step to the extension region 18 of the inner tube 16 is performed. In this step, the distal leg region 13e of the balloon 13 and the inner tube 16 are joined by heat welding. Thereby, the balloon 13 is joined to the inner tube 16 at a predetermined position in the axial direction. Note that such joining is not necessarily performed by heat welding, and may be performed by adhesion using an adhesive. Further, the positioning step and the balloon distal side joining step described above correspond to the balloon joining step.

  In addition, before performing a balloon proximal side joining process, you may perform a balloon positioning process and a balloon distal side joining process. In this case, in the balloon positioning step, the single state balloon 13 is positioned with respect to the inner tube 16, and in the subsequent balloon distal side joining step, the positioned single item balloon 13 is joined to the inner tube 16. Become. Thereafter, a balloon proximal side joining step for joining the proximal end portion of the balloon 13 to the distal end portion of the outer tube 15 is performed.

  After finishing the balloon distal side joining step, as a subsequent step, a joining step in which the outer distal tube 23 and the outer proximal tube 24 are joined by thermal welding, or the outer tube 15 is joined to the inner tube 16 by thermal welding. A joining process is performed.

  Next, a procedure when using the balloon catheter 10 having the above configuration will be described. Here, the procedure in the case of expanding the lesioned part produced in the blood vessel using the balloon catheter 10 (balloon 13) is demonstrated. FIG. 5 is an explanatory diagram for explaining the procedure. Further, here, it is assumed that the lesion is expanded by inflating the balloon 13 with a nominal pressure.

  First, a guiding catheter is inserted into a sheath introducer inserted into a blood vessel, and is inserted into the coronary artery entrance by pushing and pulling. Next, the guide wire G is inserted into the guide wire lumen of the balloon catheter 10 (specifically, the inner tube hole 31 of the inner tube 16) and the guiding catheter, and is inserted from the coronary artery entrance to the peripheral site through the lesion. Subsequently, the balloon catheter 10 is inserted into the blood vessel while being pushed or pulled along the guide wire G, and the balloon 13 is introduced (arranged) into the lesion. At this time, the balloon 13 is in a deflated state.

  When placing the balloon 13 in the lesion, the balloon 13 is positioned in a state where the distal end of the proximal contrast ring 30b is aligned with the proximal end of the lesion 38, as shown in FIG. Place. Thereafter, as shown in FIG. 5B, the balloon 13 is inflated by applying a nominal pressure to the balloon 13. Thereby, the lesioned part 38 is pressed radially outward by the straight tube region 13c of the inflated balloon 13, and the lesioned part 38 is expanded. The length S of the lesioned part 38 (specifically, the length of the lesioned part 38 in the direction in which the blood vessel extends) is longer than the length AL1 of the straight tube region 13c of the balloon 13 when the nominal pressure is applied. It is 14 mm. Therefore, a part of the distal side of the lesioned part 38 remains unexpanded. Further, in the expanded state when the nominal pressure is applied, as described above, the proximal end portion of the straight tube region 13c is located at the same position as the distal end portion of the proximal contrast ring 30b. The proximal end portion of the region 13 c is disposed at the same position as the proximal end portion of the lesioned part 38. Therefore, in the lesioned part 38, the entire region is expanded from the midway position in the length direction (specifically, the midway position at the same position as the distal end of the straight pipe region 13c).

  Next, as shown in FIG. 5C, the balloon 13 is re-contracted and moved to the distal side in order to expand the unexpanded portion that has not been expanded due to the expansion of the balloon 13 in the lesioned portion 38. At this time, the balloon 13 is moved until the distal end of the distal contrast ring 30a and the distal end of the lesioned part 38 are in the same position.

  Next, as shown in FIG. 5D, the balloon 13 is inflated by applying a nominal pressure to the balloon 13. Thereby, the unexpanded part in the lesioned part 38 is expanded. Specifically, in the expanded state, as described above, the distal end of the straight tube region 13c is located at the same position as the distal end of the distal contrast ring 30a. The part is disposed at the same position as the distal end of the lesion 38. Therefore, the lesioned part 38 is expanded to the distal end thereof by the straight tube region 13c, whereby the entire lesioned part 38 is expanded.

  Thereafter, the balloon 13 is deflated and the balloon catheter 10 is extracted from the body, thereby completing a series of operations.

  By the way, when the lesioned part 38 is hardened, the lesioned part 38 may not be sufficiently expanded even if a nominal pressure is applied to the balloon 13. In that case, a pressure higher than the nominal pressure is applied to the balloon 13 to inflate the balloon 13 and expand the lesioned part 38. Hereinafter, the work procedure in this case will be described with reference to FIG. FIG. 6 is an explanatory diagram for explaining the work procedure.

  As shown in FIG. 6A, first, the balloon 13 is placed in the lesioned part 38 in a deflated state. At this time, the balloon 13 is arranged in a state where the proximal end portion of the proximal contrast ring 30 b is aligned with the proximal end portion of the lesioned part 38.

  Next, as shown in FIG. 6B, the balloon 13 is inflated by applying a pressure higher than the nominal pressure, for example, RB pressure, to the balloon 13. Thereby, the lesioned part 38 is expanded in the radial direction by the expanded straight pipe region 13c. Specifically, in the expanded state when the RB pressure is applied, as described above, the proximal end portion of the straight tube region 13c is located at the same position as the proximal end portion of the proximal contrast ring 30b. The proximal end of 13c is located at the same position as the proximal end of the lesion 38. Accordingly, in the present catheter 10, even when the axial length AL of the straight tube region 13c is maximized (ie, AL2) by applying RB pressure to the balloon 13, the proximal end side of the straight tube region 13c is affected by the lesion. It does not protrude from the portion 38, and as a result, the occurrence of inconvenience that the protruding portion contacts a normal portion other than the lesioned portion 38 is suppressed.

  Subsequently, as shown in FIG. 6 (c), the balloon 13 is re-contracted and moved to the distal side in order to expand the unexpanded portion of the lesioned portion 38 that has not been expanded due to the inflation of the balloon 13. At this time, the balloon 13 is moved until the distal end portion of the distal contrast ring 30a is located at the same position as the distal end portion of the lesioned portion 38, as in the case of FIG.

  Thereafter, as shown in FIG. 5 (d), the balloon 13 is inflated by applying RB pressure to the balloon 13. Thereby, the unexpanded area | region of the lesioned part 38 is expanded by the expanded straight pipe | tube area | region 13c. Specifically, in the expanded state, as described above, the distal end portion of the straight tube region 13c is located at the same position as the distal end portion of the distal contrast ring 30a. The end is located at the same position as the distal end of the lesion 38. Therefore, the distal side of the straight tube region 13c is prevented from protruding from the lesioned part 38, similarly to the proximal side of the straight tube region 13c described above.

  The balloon catheter 10 is used mainly for passing through a blood vessel as described above to expand a lesioned portion 38 (stenosis or occlusion) generated in the blood vessel. It can also be used to expand a lesion that has occurred in a “tube” in a living body such as a tube.

  As mentioned above, according to the structure of this embodiment explained in full detail, the following outstanding effects are acquired.

  The proximal contrast ring 30b is attached to the inner tube 16, and then the proximal end (corresponding to the displacement end) of the straight tube region 13c is closer than the proximal contrast ring 30b when RB pressure is applied. The balloon 13 was positioned with respect to the inner tube 16 so as not to be displaced to the distal side, and the balloon 13 was attached to the inner tube 16 in the positioned state. In this case, even when RB pressure is applied to the balloon 13 in the catheter 10 and the extension of the straight tube region 13c in the axial direction is maximized, the straight tube region 13c is located closer to the proximal side than the proximal contrast ring 30b. It does not protrude. Therefore, if the balloon 13 is disposed in a state where the proximal end of the proximal contrast ring 30b and the end of the lesion are aligned with the lesion in the body, the pressure applied to the balloon 13 can be reduced. Regardless, the straight tube region 13c can be prevented from reaching a portion other than the lesioned portion, that is, a normal portion. Thereby, the inconvenience which the straight pipe | tube area | region 13c contacts the normal site | part in a body unintentionally can be suppressed.

  Specifically, when the RB pressure is applied, the balloon 13 is set so that the proximal end of the proximal contrast ring 30b and the proximal end of the straight tube region 13c are in the same position in the axial direction of the inner tube 16. Is positioned and joined to the inner tube 16, and when the balloon 13 is positioned and positioned as described above with respect to the lesioned portion and RB pressure is applied to the balloon 13, the proximal end portion of the straight tube region 13c and the lesioned portion are disposed. And the end of the same position. Therefore, the lesioned part can be expanded to the end part. In addition, when a nominal pressure is applied to the balloon 13, a part on the end side of the lesion becomes an unexpanded region, but according to such a configuration, the unexpanded region can be relatively reduced. Therefore, in this case, the lesioned part can be suitably expanded.

  The length XL in the axial direction of the proximal contrast ring 30b is set to the same length as the extension amount W of the straight tube region 13c (the displacement amount of the proximal end portion of the straight tube region 13c). When the nominal pressure is applied, the distal end of the proximal contrast ring 30b is in the same position as the proximal end of the straight tube region 13c in the axial direction, and when the RB pressure is applied, the proximal end of the proximal contrast ring 30b The balloon 13 was positioned and joined to the inner tube 16 so that the portion was at the same position as the proximal end of the straight tube region 13c. Thereby, when applying a nominal pressure to the balloon 13 to expand the lesion, the balloon 13 is aligned with the distal end of the proximal contrast ring 30b and the end of the lesion with respect to the lesion. If it arranges in this way, a lesioned part can be expanded to the edge part. Further, when the lesion is expanded by applying RB pressure to the balloon 13, the proximal end of the proximal contrast ring 30b and the end of the lesion are aligned with the lesion. The lesion can be expanded to its end. Therefore, in this case, the lesion can be suitably expanded regardless of whether the nominal pressure or the RB pressure is applied to the balloon 13.

  The distance MX between the end portions of the proximal contrast ring 30b and the distal contrast ring 30a that are separated from each other is the same as the length AL2 of the straight tube region 13c in the axial direction when the RB pressure is applied. So that the proximal end of the straight tube region 13c is not displaced more proximally than the proximal contrast ring 30b when RB pressure is applied, and The balloon 13 was positioned and joined to the inner tube 16 so that the distal end of the straight tube region 13c was at the same position as the distal end of the distal contrast ring 30a at the time of nominal pressure. In this case, at the time of RB pressure, the straight tube region 13c does not protrude to the proximal side of the proximal contrast ring 30b and the distal side of the distal contrast ring 30a. It is possible to suppress the inconvenience that the same region 13c comes into contact with a normal part in the body on both ends.

  The contrast ring 30 is positioned and attached to the tube 16 based on the distance from the distal end of the inner tube 16 determined in advance to the contrast ring 30, and then the distal end of the inner tube 16 also determined in advance. The balloon 13 was positioned and joined to the inner tube 16 based on the distance from the part to the balloon 13. In this case, it is possible to attach the balloon 13 to a predetermined position of the inner tube 16 without checking the position of the contrast ring 30 that is disposed inside the balloon 13 and is difficult to visually recognize. Therefore, the workability can be improved, and the positioning accuracy of the balloon 13 can be ensured.

The present invention is not limited to the above embodiment, and may be implemented as follows, for example.
(1) In the above-described embodiment, the proximal contrast ring 30b is attached to the inner tube 16 so that the proximal end thereof is at the same position as the proximal end of the straight tube region 13c when RB pressure is applied. However, this is changed, and the proximal contrast ring 30b is placed on the inner tube 16 so that the proximal end thereof is located more proximally than the proximal end of the straight tube region 13c when the RB pressure is applied. It may be attached. Specifically, the configuration shown in FIGS. 7A to 7C can be considered. 7A to 7C show the configuration around the balloon 13 when the RB pressure is applied. In FIG. 7A, the proximal contrast ring 30b has a proximal end of the contrast ring 30b proximal to the proximal end of the straight tube region 13c, and a distal end of the contrast ring 30b. It arrange | positions so that an edge part may become a distal side. In FIG.7 (b), the proximal side contrast ring 30b is arrange | positioned so that the distal end may become the same position as the proximal end part of the straight pipe | tube area | region 13c. In FIG.7 (c), the whole proximal contrast ring 30b is arrange | positioned more proximally than the straight pipe | tube area | region 13c. 7A to 7C, when the RB pressure is applied, the straight tube region 13c does not protrude beyond the proximal contrast ring 30b.

  (2) The length XL of the contrast rings 30a and 30b may be larger or smaller than the extension amount W of the straight tube region 13c. Further, the length XL may be different between the distal contrast ring 30a and the proximal contrast ring 30b. In any case, the proximal contrast ring 30b is positioned so that its proximal end is at the same position as or proximal to the proximal end of the straight tube region 13c when RB pressure is applied. The balloon 13 is attached to the inner tube 16.

  (3) Instead of attaching the distal contrast ring 30 a to the inner tube 16, only the proximal contrast ring 30 b may be attached to the inner tube 16.

  (4) In the above embodiment, the distal contrast ring 30a is provided corresponding to the distal end of the straight tube region 13c, and the proximal contrast ring 30b is provided corresponding to the proximal end of the region 13c. However, this may be changed and only one contrast ring may be provided so as to straddle each of the distal end portion and the proximal end portion of the straight tube region 13c. For example, the contrast ring 55 shown in FIG. 8 has the same axial length as the length AL2 of the straight tube region 13c when the RB pressure is applied, and is made of, for example, synthetic resin. The contrast ring 55 is attached to the inner tube 16 so that both ends thereof are at the same positions as both ends of the straight tube region 13c when the RB pressure is applied. In this case, both ends of the straight tube region 13c in the axial direction do not protrude outside the contrast ring 55 when the RB pressure is applied.

  (5) In the above-described embodiment, the two contrast rings 30a and 30b are each positioned and attached with reference to the distal end portion of the inner tube 16 in the contrast portion attaching step, but this may be changed. For example, the distance from the distal end of the distal contrast ring 30a to the proximal end of the proximal contrast ring 30b is RB between the two contrast rings 30a and 30b by a predetermined distance in the axial direction. The straight tube region 13c is attached to the inner tube 16 while being separated from each other by a distance equal to the axial length AL2 of the straight tube region 13c when pressure is applied. However, at this time, a margin for joining the balloon 13 is secured on the distal side of the distal contrast ring 30 a in the inner tube 16. Then, in the balloon positioning step, the contrast rings 30a and 30b and a predetermined portion of the balloon 13 (for example, the distal end of the distal leg region 13e, each end of the straight tube region 13c, etc.) in the axial direction are relative to each other. The balloon 13 is positioned with respect to the inner tube 16 while adjusting the distance. In this case, for example, if the balloon 13 is made of a material that can be seen through, the positioning of the contrast rings 30a and 30b and a predetermined portion of the balloon 13 can be easily performed.

  (6) FIG. 9 shows another example of the balloon catheter 60. FIG. 9A shows a case where a nominal pressure is applied to the balloon 13 of the catheter 60, and FIG. 9B shows a case where an RB pressure is applied. In the balloon catheter 60 shown in FIG. 9, the tip end body 61 is joined to the distal end portion of the inner tube 16 coaxially with the inner tube 16 by welding. The distal leg region 13e is thermally welded. Specifically, the proximal end side of the tip end body 61 has an enlarged diameter, and the distal end portion of the inner tube 16 is inserted into the enlarged diameter portion, and both are heat-welded. The tip end body 61 is formed in a tubular shape from a synthetic resin and has a lower rigidity than the inner tube 16. In this configuration, the inner tube 16 and the tip end body 61 correspond to the inner shaft.

  As shown in FIGS. 9A and 9B, in the present catheter 60, when the pressure applied to the balloon 13 is increased from the nominal pressure to the RB pressure, as in the catheter 10 of the above embodiment, the balloon 13 The straight pipe region 13c extends in the axial direction. Thereby, the length AL in the axial direction of the straight pipe region 13c is changed from AL3 to AL4 (AL3 <AL4). In this case, in the catheter 10 of the above embodiment, only the proximal end portion is displaced and the distal end portion is not displaced among the both end portions of the straight tube region 13c, but in the present catheter 60, the straight tube region 13c is not displaced. Both ends are displaced. Specifically, the proximal end portion of the straight tube region 13c is displaced proximally by h1, and the distal end portion of the straight tube region 13c is displaced distally by h2. In this catheter 60, the distal end portion of the balloon 13 is joined to the tip portion 61 having relatively low rigidity and elasticity, and the distal end portion of the straight tube region 13c is applied when RB pressure is applied. This is because this displacement is allowed by the extension of the tip end body 61.

  Therefore, in the present catheter 60, the attachment positions of the contrast rings 30a and 30b with respect to the inner tube 16 are determined in consideration of the displacements at both ends of the straight tube region 13c. Among the contrast rings 30a and 30b, the proximal contrast ring 30b has a length XL1 in the axial direction set to the same value as h1, and the distal contrast ring 30a has a length XL2 in the axial direction. Is set to the same value as h2. Then, as in the case of the above embodiment, the proximal side contrast ring 30b is arranged so that its distal end is located at the same position as the proximal end of the straight tube region 13c when applying the nominal pressure, and The RB pressure is attached to the inner tube 16 so that its proximal end is in the same position as the proximal end of the straight tube region 13c. On the other hand, the distal contrast ring 30a is positioned so that its proximal end is located at the same position as the distal end of the straight tube region 13c when the nominal pressure is applied, and when the RB pressure is applied. The distal end portion is attached to the inner tube 16 so as to be in the same position as the distal end portion of the straight tube region 13c. The distal contrast ring 30 a is attached to the inner tube 16 with its distal end in contact with the proximal end of the tip end body 61. In this case, the length DL in the axial direction of the tip part 61 is the extension length CL of the tip part 61 to the distal side of the balloon 13 and the distal cone leg length BL of the balloon 13. This is the same as the value obtained by subtracting the length XL2 of the distal contrast ring 30a from the sum (DL + X2 = BL + CL).

  As a manufacturing process of the balloon catheter 60, first, a tip tip joining step is performed in which the tip tip body 61 is joined to the distal end portion of the inner tube 16 by heat welding. In the subsequent contrast ring attaching step, first, the distal contrast ring 30 a is attached to the inner tube 16 with its distal end abutting against the proximal end of the tip end body 61. Thereafter, the proximal contrast ring 30b is attached to the inner tube 16 with its proximal end aligned to a position proximal to the distal end of the distal contrast ring 30a by dimension AL4. At this time, the proximal contrast ring 30b may be attached to the inner tube 16 with its distal end aligned with the position on the proximal side by the dimension AL3 from the proximal end of the distal contrast ring 30a. .

  Thereafter, a balloon distal side joining step is performed, and in the subsequent balloon positioning step, a part of the tip portion 61 is extended to the distal side of the balloon 13 by the dimension CL, whereby the balloon 13 is moved to the inner tube 16 ( In the subsequent balloon distal side joining step, the distal leg region 13e of the balloon 13 is joined to the tip part 61 by heat welding.

  According to the balloon catheter 60, when the RB pressure is applied, the straight tube region 13c can be prevented from protruding further to the distal side than the distal contrast ring 30a, and more proximal than the proximal contrast ring 30b. It can be suppressed from protruding to the side. Therefore, when the balloon 13 is arranged on the lesioned part, the straight pipe region 13c is arranged even if the end on either side of the both ends of the straight tube region 13c is aligned with the end of the lesioned part. Can suppress the inconvenience of contacting a normal site other than the lesion.

  (7) By the way, in the configuration of (6) above (that is, the configuration of FIG. 9), the outer tube 15 (outer distal tube 23) to which the proximal end of the balloon 13 is joined is formed, for example, as a highly rigid one. (In other words, when the outer tube 15 is less likely to shrink or bend), the displacement of the proximal end portion of the straight tube region 13c located at a position relatively close to the joint portion is changed. It is assumed that 15 cannot be absorbed. In that case, even if RB pressure is applied to the balloon 13, it is assumed that the proximal end of the straight tube region 13c is restricted from being displaced toward the proximal side. Therefore, in such a case, when the pressure applied to the balloon 13 is increased from the nominal pressure to the RB pressure, only the distal end portion of the both ends of the straight tube region 13c is displaced. Even in such a case, with the catheter 60 of this example, the straight tube region 13c can be prevented from protruding beyond the proximal contrast ring 30b when the RB pressure is applied.

  DESCRIPTION OF SYMBOLS 10 ... Balloon catheter, 13 ... Balloon, 13c ... Straight pipe | tube area | region as an expansion | swelling effective area | region, 15 ... Outer tube as an outer shaft, 16 ... Inner tube as an inner shaft, 30 ... Contrast ring as a contrast part, 30a ... No. 2 a distal contrast ring as a contrast section, 30b... A proximal contrast ring as a first contrast section, 60 a balloon catheter, 61 a tip body.

Claims (5)

A tubular outer shaft;
An inner shaft inserted into the outer shaft in a state where a part of the outer shaft is extended to the distal side of the outer shaft;
Provided to cover the extension portion of the inner shaft from the outside, one end portion is joined to the distal end portion of the outer shaft and the other end portion is joined to the extension portion of the inner shaft With balloons,
An imaging part attached to the area covered by the balloon on the inner shaft,
The balloon is inflated when a fluid is supplied to the inside thereof and a pressure within a predetermined range defined in advance is applied, and is contracted when the fluid is discharged. Applied to a balloon catheter having an inflated effective region that is inflated into the most expanded part,
A contrast part attaching step for attaching the contrast part to the inner shaft;
The displacement end portion that is displaced in the axial direction by the application of pressure among the both end portions in the axial direction of the inner shaft in the effective inflation region of the balloon is in a state where the maximum pressure within the predetermined range is applied. A balloon joining step of positioning the balloon with respect to the inner shaft so that the balloon is not displaced more than the contrast section, and joining the balloon to the inner shaft in the positioned state;
A method for producing a balloon catheter, comprising:   In the balloon joining step, when applying the maximum pressure, the balloon is placed on the inner side so that the position of the end of the contrast portion in the axial direction of the inner shaft is the same as the end of the effective expansion region. The method for manufacturing a balloon catheter according to claim 1, wherein the balloon catheter is positioned and joined to the shaft. The pressure within the predetermined range includes a reference pressure that expands the effective expansion region so that the outer diameter of the effective expansion region becomes a predetermined outer diameter defined in advance.
The contrast portion has the same length as the displacement amount that the displacement end of the effective expansion region is displaced as the pressure applied to the balloon rises from the reference pressure to the maximum pressure. Have
In the balloon bonding step, one end of the contrast unit is located at the same position as the displacement end of the expansion effective region in the axial direction when the reference pressure is applied, and the other end of the contrast unit is applied when the maximum pressure is applied. The method of manufacturing a balloon catheter according to claim 2, wherein the balloon is positioned and joined to the inner shaft so that the balloon is positioned at the same position as the displacement end of the inflation effective region. The pressure within the predetermined range includes a reference pressure that expands the effective expansion region so that the outer diameter of the effective expansion region becomes a predetermined outer diameter defined in advance.
One of the two end portions in the effective expansion region is the displacement end portion, and the other is the non-displacement end portion that does not displace in the axial direction, and the inner shaft corresponds to the displacement end portion as the contrast portion. Applied to a balloon catheter in which a first contrast portion provided as a first contrast portion and a second contrast portion provided corresponding to the non-displacement end portion are mounted apart from each other,
In the contrast portion attaching step, the distance between the end portion on the opposite side to the second contrast portion in the first contrast portion and the end portion on the opposite side to the first contrast portion in the second contrast portion, The first contrast unit and the second contrast unit are attached to the inner shaft so as to be equal to or longer than the axial length of the effective expansion region when the maximum pressure is applied,
In the balloon joining step, in the axial direction, the displacement end portion is not displaced more than the first contrast portion on the displacement side of the displacement end portion when the maximum pressure is applied, and 4. The balloon is positioned and joined to the inner shaft so that the non-displacement end portion is positioned within the length range of the second contrast portion at the reference pressure. The manufacturing method of the balloon catheter as described in any one. A contrast reference portion that defines a reference position for balloon joint on the inner shaft, and the displacement end portion of the expansion effective region is prevented from being displaced more than the contrast portion on the displacement side when the maximum pressure is applied. The position of the part is obtained in advance as a distance from the joining reference part,
In the contrast portion attaching step, based on the distance from the joining reference portion, the contrast portion is positioned and attached to the inner shaft,
The balloon catheter according to any one of claims 1 to 4, wherein, in the balloon joining step, the balloon is positioned and joined to the inner shaft based on a distance from the joining reference portion. Manufacturing method.

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