Catheter

Abstract

A catheter according to the present disclosure comprises: a laser emitter; a tubular member, the inside of which are divided into a housing space capable of housing the laser emitter, and a guide wire insertion hole; and an expansion member. The tubular member includes: an inner part that is covered by the expansion member and includes a laser transmission section through which laser emitted from the laser emitter can transmit in the radial direction; and a distal end part that is continuous with the inner part on the distal side of the expansion member in the longitudinal direction of the tubular member. The inner part of the tubular member does not have the guide wire insertion hole demarcated therein and has the housing space demarcated therein. The distal end part of the tubular member does not have the housing space demarcated therein and has the guide wire insertion hole demarcated therein.

Description

catheter

[0001] The present disclosure relates to catheters.

[0002] Conventionally, probes that convert laser light into shock waves and utilize the shock wave stress to perform various treatments have been known. Patent Document 1 discloses this type of probe. Also known is a probe that converts the vaporization expansion force of a liquid obtained by spark discharge in a liquid atmosphere into mechanical force to perform treatment. Patent Document 2 discloses this type of probe.

[0003] JP-A-5-300911 Publication Special Publication No. 2015-522344

[0004] However, the probes described in Patent Documents 1 and 2 still have room for improvement in terms of both the efficiency of applying the force required for treatment to the target site, such as crushing a calcified area in a blood vessel, and the ease of passage within the living body.

[0005] An object of the present disclosure is to provide a catheter that easily achieves both efficiency in treating a target site and ease of passage within a living body.

[0006] A catheter according to a first aspect of the present disclosure is a catheter comprising: (1) a laser emitter capable of emitting a laser; a tubular member defining an internal storage space capable of accommodating the laser emitter and a guidewire insertion hole through which a guidewire can be inserted; and an expansion member covering the radial outside of the tubular member and capable of expanding and contracting in the radial direction, wherein the tubular member comprises: an inner portion that is covered by the expansion member on the radial inside of the expansion member and includes a laser transparent portion that is radially transparent to the laser emitted from the laser emitter accommodated in the storage space; and a distal end portion that is connected to the inner portion on the distal side of the longitudinal direction of the tubular member relative to the expansion member, wherein the inner portion of the tubular member does not define the guidewire insertion hole but defines the storage space; and the distal end portion of the tubular member does not define the storage space but defines the guidewire insertion hole.

[0007] A catheter according to one embodiment of the present disclosure is the catheter described in (1) above, wherein (2) the storage space extends in the longitudinal direction so as to include the central axis of the expansion member in an expanded state at the position of the inner portion.

[0008] A catheter according to one embodiment of the present disclosure is the catheter described in (1) or (2) above, wherein the guidewire insertion hole extends from a distal opening formed on the distal end surface of the distal end of the tubular member to a proximal opening formed on the side surface of the distal end of the tubular member, proximal to the distal opening in the longitudinal direction.

[0009] A catheter according to one embodiment of the present disclosure is the catheter described in (3) above, wherein the distal opening of the guidewire insertion hole is formed at a position through which the central axis of the expansion member in an expanded state passes.

[0010] A catheter according to one embodiment of the present disclosure is (5) the catheter described in (3) or (4) above, wherein the guidewire insertion hole comprises a main hole portion extending from the distal opening to the proximal side in the longitudinal direction, and an inclined hole portion connecting the proximal opening and the main hole portion and extending at an angle with respect to the longitudinal direction.

[0011] A catheter according to one embodiment of the present disclosure is the catheter described in (5) above, wherein (6) the expansion member comprises an expansion main body portion that is cylindrically expandable, and a distal tapered expansion portion that is connected to the distal side of the expansion main body portion and whose expansion diameter decreases from the proximal side toward the distal side in the longitudinal direction, and the inclination angle of the distal tapered expansion portion with respect to the longitudinal direction is equal to or less than the inclination angle of the inclined hole portion of the guidewire insertion hole with respect to the longitudinal direction.

[0012] A catheter according to one embodiment of the present disclosure is (7) the catheter according to any one of (1) to (6) above, wherein the distal side of the accommodating space in the longitudinal direction is closed.

[0013] A catheter according to one embodiment of the present disclosure is (8) a catheter according to any one of (1) to (7) above, wherein, when the guidewire insertion hole is a distal guidewire insertion hole, the tubular member defines a proximal guidewire insertion hole through which the guidewire inserted in the distal guidewire insertion hole can be inserted at a position proximal to the expansion member in the longitudinal direction.

[0014] A catheter according to one embodiment of the present disclosure is (9) a catheter according to any one of (1) to (8) above, wherein the expansion member has a window portion that can release the laser emitted from the laser emitter or a pressure wave caused by the laser radially outward.

[0015] A catheter according to one embodiment of the present disclosure is the catheter described in (9) above, wherein the window portion of the expansion member is provided with a shock wave generating portion capable of generating a shock wave as the pressure wave by the laser emitted from the laser emitter.

[0016] A catheter according to one embodiment of the present disclosure is the catheter described in any one of (1) to (10) above, wherein the inner portion of the tubular member is provided with a marker that is radiopaque or ultrasonically visible.

[0017] A catheter according to one embodiment of the present disclosure is (12) the catheter according to any one of (1) to (11) above, wherein the laser emitter comprises: a laser emitting section in which a laser fiber capable of emitting the laser is not covered with a fiber coating layer; and a laser non-emitting section in which the laser fiber is covered with the fiber coating layer.

[0018] A treatment method as a second aspect of the present disclosure is (13) a treatment method including: a preparation step of preparing the catheter described in (1) above; an expansion step of expanding the expansion member of the catheter at a target site; and a treatment step of emitting the laser from the laser emitter toward a shock wave generating unit capable of generating shock waves as pressure waves by the laser emitted from the laser emitter, and treating the target site with the shock waves generated in the shock wave generating unit.

[0019] According to the present disclosure, it is possible to provide a catheter that easily achieves both efficiency in treating a target site and ease of passage within a living body.

[0020] 1 is a diagram showing a catheter according to one embodiment of the present disclosure. FIG. 1 is a cross-sectional view of the catheter taken at line II in FIG. 1. FIG. 2 is a diagram showing a state in which an expansion member of the catheter shown in FIG. 1 is expanded. FIG. 3 is a cross-sectional view of the catheter shown in FIG. 3 at the same position as FIG. 2. FIG. 3 is a cross-sectional view of the catheter shown in FIG. 3 taken along a plane along the longitudinal direction. FIG. 4 is a diagram showing details of a guidewire insertion hole inside a distal end portion of a tubular member. FIG. 5 is an explanatory view for explaining the principle of generation of laser-induced shock waves. FIG. 6 is a flowchart showing a treatment method according to one embodiment of the present disclosure.

[0021] Hereinafter, an embodiment of a catheter according to the present disclosure will be illustrated and described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals.

[0022] FIG. 1 is a diagram showing a catheter 1 as one embodiment of a catheter according to the present disclosure. For ease of explanation, a guidewire GW is also shown in FIG. 1 by a two-dot chain line. FIG. 1 shows the catheter 1 inserted into a blood vessel BV. The catheter 1 is a medical instrument that is inserted into the blood vessel BV and is capable of crushing a calcified region X in the blood vessel BV by utilizing shock waves as pressure waves generated by laser irradiation. The catheter 1 is inserted into the blood vessel BV along the guidewire GW. In this embodiment, the calcified region X in the blood vessel BV is exemplified as a target site to be treated by the catheter 1, but the catheter 1 may also be used to treat other target sites.

[0023] As shown in Fig. 1, the catheter 1 of this embodiment includes a laser emitter 20, a tubular member 2, and an expansion member 3. Fig. 1 shows the catheter 1 percutaneously inserted into a patient's blood vessel BV along a guidewire GW, with the expansion member 3 introduced up to the position of a lesion, which is a target site where a calcified region X has formed. Fig. 1 also shows the expansion member 3 in a contracted state. In the contracted state, the expansion member 3 is guided through the blood vessel BV to the lesion.

[0024] Hereinafter, in the catheter 1, the longitudinal direction of the tubular member 2 will be referred to as the "longitudinal direction A." Furthermore, in the catheter 1, the direction around the axis of the tubular member 2 will be referred to as the "circumferential direction B." Furthermore, in the catheter 1, the radial direction of the tubular member 2, which is the radial direction of an imaginary circle with the tubular member 2 as its central axis in a cross section perpendicular to the longitudinal direction A of the tubular member 2, will be referred to as the "radial direction C." Furthermore, within the longitudinal direction A, the direction from the base end side (hand side) of the catheter 1 manipulated by an operator such as a surgeon toward the tip side of the catheter 1 inserted into a living body will be referred to as the "distal" or "distal side A1," and the direction from the tip side of the catheter 1 toward the base end side of the catheter 1 will be referred to as the "proximal" or "proximal side A2."

[0025] Fig. 2 is a cross-sectional view of the catheter 1 taken along line II in Fig. 1. Figs. 3 to 5 show the expanded state of the expansion member 3 in the contracted state shown in Figs. 1 and 2. Specifically, Fig. 3 shows the expanded state of the expansion member 3 in the contracted state shown in Fig. 1 within the blood vessel BV. Fig. 4 is a cross-sectional view taken at the same position as Fig. 2, showing the expansion member 3 in an expanded state. Fig. 5 is a cross-sectional view taken along the longitudinal direction A of the catheter 1 in which the expansion member 3 is in an expanded state.

[0026] 3, the expansion member 3 is positioned at a calcified region X in a blood vessel BV as a target site. Next, the expansion member 3 contacts the calcified region X and expands to apply pressure in the radial direction C.

[0027] 5 , the tubular member 2 defines an accommodation space 6 capable of accommodating a laser emitter 20 capable of emitting a laser, and a guidewire insertion hole 7 through which a guidewire GW can be inserted. As will be described in detail later, the laser emitted from the laser emitter 20 located in the accommodation space 6 is used to treat a target site via the expansion member 3.

[0028] The expansion member 3 covers the outside of the tubular member 2 in the radial direction C, and is configured to be able to expand and contract in the radial direction C.

[0029] 5 , the tubular member 2 has an inner portion 2a that is covered by the expansion member 3 on the inner side in the radial direction C relative to the expansion member 3. The inner portion 2a includes a laser transmitting portion 2a1 that can transmit the laser emitted from the laser emitter 20 in the radial direction C.

[0030] 5, the tubular member 2 has a distal end portion 2b that is continuous with the inner portion 2a on the distal side A1 in the longitudinal direction A relative to the expansion member 3. More specifically, the distal end portion 2b in this embodiment is continuous with the inner portion 2a on the distal side A1 so that its central axis substantially coincides with the central axis of the inner portion 2a.

[0031] The inner portion 2a of the tubular member 2 does not define a guidewire insertion hole 7 therein, but defines an accommodation space 6 therein. In contrast, the distal end portion 2b of the tubular member 2 does not define a accommodation space 6 therein, but defines a guidewire insertion hole 7 therein. The accommodation space 6 and the guidewire insertion hole 7 do not communicate with each other. This makes it easy to arrange the accommodation space 6 and the guidewire insertion hole 7 side by side along the central axis O of the expansion member 3 in the expanded state, without changing the radial positions of the accommodation space 6 and the guidewire insertion hole 7. This makes it easy to reduce the diameters of both the inner portion 2a and the distal end portion 2b of the tubular member 2. This improves the passability of the catheter 1 inside a living body.

[0032] Furthermore, it becomes easier to arrange the accommodation space 6 and the guidewire insertion hole 7 side by side along the central axis O of the expansion member 3 in an expanded state so as to include the central axis O of the expansion member 3 in an expanded state. Therefore, it is possible to suppress variation in the distance L2 in the radial direction C (see FIG. 5 ) from the laser emitter 20 located in the accommodation space 6 to the expansion member 3 at the position of the inner portion 2a, depending on the position in the circumferential direction B. This suppresses variation in the intensity of the laser emitted from the laser emitter 20 located in the accommodation space 6 and emitted outward in the radial direction C from the expansion member 3, or in the intensity of the pressure wave generated by the laser emitted from the laser emitter 20 located in the accommodation space 6 and emitted outward in the radial direction C from the expansion member 3. This improves the efficiency of treating a target site, such as a calcified region X, in a blood vessel BV.

[0033] As described above, the catheter 1 can easily achieve both efficiency in treating a target site and ease of passage within a living body.

[0034] The catheter 1 of this embodiment will be described in further detail below with reference to Figures 1 to 6. Figure 6 is a diagram showing the details of the guidewire insertion hole 7 inside the distal end portion 2b.

[0035] <Laser Emitter 20> As shown in FIG. 5, the laser emitter 20 of this embodiment includes a laser emitter main body 21 and a connector portion 22 attached to the proximal end of the laser emitter main body 21.

[0036] The laser emitting body 21 comprises a laser emitting section 23 located at its distal end, a drive transmission connector 24 located at its proximal end and covered by a connector section 22, and a long laser non-emitting section 25 extending between the laser emitting section 23 and the drive transmission connector 24.

[0037] The laser emission section 23 in this embodiment is a portion of the laser fiber 31 (see FIGS. 2 and 4) capable of emitting a laser beam that is not covered with the fiber coating layer 32 (see FIGS. 2 and 4). In contrast, the laser non-emission section 25 in this embodiment is a portion of the laser fiber 31 capable of emitting a laser beam that is covered with the fiber coating layer 32. The material of the fiber coating layer 32 may be any light-blocking material that can block the laser beam emitted from the laser fiber 31, and may be, for example, a resin layer such as an ultraviolet-curable resin (UV-curable resin), a metal layer such as a coil, or the like. The fiber coating layer 32 may be a single layer, or multiple layers may be laminated.

[0038] The connector 22 is configured to be connectable to a drive device connected to an optical source. When the connector 22 is connected to the drive device, the laser fiber 31 is optically connected to the drive device. When the connector 22 is connected to the drive device, the drive device is able to drive the laser emitting body 21 in at least one of the longitudinal direction A and the circumferential direction B via the drive transmission connector 24.

[0039] More specifically, the connector part 22 of this embodiment includes a connector main body 22a connectable to the drive device and an inner cylindrical part 22b protruding from the connector main body 22a toward the distal side A1. The proximal end of the laser emitting main body 21 is fitted and fixed within the inner cylindrical part 22b of the connector part 22. The inner cylindrical part 22b of the connector part 22 of this embodiment includes a flange part 22b1 protruding outward in the radial direction C.

[0040] The laser emission unit 23 may be configured to emit a laser beam only in a partial region in the circumferential direction B, toward the outside in the radial direction C. In such a case, by rotating the laser emission main body 21 in the circumferential direction B using a driving device, the laser beam emitted from the laser emission unit 23 toward the outside in the radial direction C can be emitted over the entire area in the circumferential direction B. The irradiation range L1 (see FIG. 7 ) in the circumferential direction B of the light absorption layer 40 a3 (see FIG. 5 ) of the extension member 3, onto which the laser beam from the laser emission unit 23 of the laser emitter 20 is irradiated, may be set appropriately. Furthermore, by moving the laser emission main body 21 in the longitudinal direction A while rotating it in the circumferential direction B using a driving device, the laser beam can be emitted from the laser emission unit 23 over the entire area in the circumferential direction B over a predetermined range in the longitudinal direction A. Furthermore, the laser emission unit 23 may be configured to emit a laser beam radially over the entire area in the circumferential direction B. In such a case, by using a driving device to move the laser emitting body 21 in the longitudinal direction A without rotating it in the circumferential direction B, it is possible to emit laser from the laser emitting section 23 over a predetermined range in the longitudinal direction A and over the entire area in the circumferential direction B.

[0041] The laser emitter 20 is inserted into the accommodating space 6 inside the tubular member 2. To improve the insertability of the laser emitter 20 through the accommodating space 6, the non-laser emitting section 25 preferably includes a coating section whose outer surface is formed with a hydrophilic coating. The coating section may be, for example, a hydrophilic polymer. Examples of hydrophilic polymers that can be used include cellulose-based polymers, polyethylene oxide-based polymers, maleic anhydride-based polymers (e.g., maleic anhydride copolymers such as methyl vinyl ether-maleic anhydride copolymers), acrylamide-based polymers (e.g., polyacrylamide, glycidyl methacrylate-dimethylacrylamide block copolymers), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone, and derivatives thereof. The coating section may be formed, for example, by dip coating.

[0042] The laser emitter 20 of this embodiment may be configured to emit a laser capable of generating laser-induced shock waves in the light absorption layer 40a3 (see FIG. 5 ), which will be described later, of the expansion member 3 of the catheter 1, and may be configured to emit, for example, a microsecond pulse laser, a nanosecond pulse laser, a picosecond laser, a femtosecond pulse laser, etc. The repetition frequency of the pulse laser emitted from the laser emitter 20 may be, for example, 1 to 500 Hz.

[0043] A contrast marker 26 having X-ray contrast is provided near the position of the laser emission unit 23 of the laser emitter 20. In this way, the operator of the catheter 1, such as a surgeon, can confirm the position of the laser emission unit 23 of the laser emitter 20 by checking the contrast marker 26 during surgery. The contrast marker 26 is not limited to having X-ray contrast and may be, for example, visible in ultrasound.

[0044] <Tubular member 2> As shown in Fig. 5 , the tubular member 2 of this embodiment includes a tubular main body 8 and a distal tip 9. The distal tip 9 is attached to the distal side A1 of the tubular main body 8 in the longitudinal direction A. The accommodation space 6 of this embodiment is defined inside the tubular main body 8. The guidewire insertion hole 7 of this embodiment is defined inside the distal tip 9.

[0045] Furthermore, the tubular member 2 of this embodiment includes, in addition to the above-described inner portion 2a and distal end portion 2b, a main body portion 2c that is continuous with the inner portion 2a on the proximal side A2 in the longitudinal direction A with respect to the expansion member 3. The inner portion 2a and main body portion 2c of this embodiment are configured by a tubular main body 8. The accommodation space 6 of this embodiment is defined inside the tubular main body 8, spanning the inner portion 2a and the main body portion 2c. The distal end portion 2b of this embodiment is configured by a distal tip 9.

[0046] As described above, the inner portion 2a includes the laser transmitting portion 2a1 that can transmit, in the radial direction C, the laser emitted from the laser emitter 20 located in the accommodation space 6. As shown in Fig. 5 , the laser emitter 20 is inserted into the accommodation space 6 until the laser emitter 23 located at the distal end thereof is located inside the inner portion 2a. The laser emitted from the laser emitter 23 located inside the inner portion 2a transmits outward in the radial direction C through the laser transmitting portion 2a1 of the inner portion 2a.

[0047] The light-transmitting material that makes up the laser transmitting portion 2a1 is not particularly limited as long as it is a material that can transmit the laser from the laser emitter 20, and examples thereof include polymer materials such as polyolefin (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these), polyvinyl chloride, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, polyimide, fluororesin, and mixtures thereof. The laser transmitting portion 2a1 may be transparent in the radial direction C, for example.

[0048] In this embodiment, the inner portion 2a includes a light-shielding portion 2a2 in addition to a laser-transmitting portion 2a1. The laser-transmitting portion 2a1 is a portion of the light-transmitting material that is not covered with a light-shielding material having a lower transmittance than the light-transmitting material. In contrast, the light-shielding portion 2a2 is a portion of the light-transmitting material that is covered with a light-shielding material. The light-shielding material is not particularly limited as long as it has a lower transmittance of the laser from the laser emitter 20 than the light-transmitting material that constitutes the laser-transmitting portion 2a1. Examples of light-shielding materials that can be used include various metal materials such as titanium oxide, barium sulfate, zinc oxide, silver, and aluminum. Furthermore, the light-shielding material may be a resin containing particles of the above-mentioned metal materials, carbon black, or the like.

[0049] The laser transmitting portion 2a1 of the inner portion 2a is formed over the entire area in the circumferential direction B. The laser transmitting portion 2a1 of the inner portion 2a may be formed, for example, over only a part of the inner portion 2a in the longitudinal direction A. In such a case, the remaining part of the inner portion 2a in the longitudinal direction A may be constituted by the light-shielding portion 2a2. Furthermore, the laser transmitting portion 2a1 of the inner portion 2a may be formed, for example, over the entire area of ​​the inner portion 2a in the longitudinal direction A. Therefore, the inner portion 2a may be constituted, for example, by only the laser transmitting portion 2a1.

[0050] The accommodation space 6 extends in the longitudinal direction A at the position of the inner portion 2a so as to include the central axis O of the expansion member 3 in an expanded state. By doing so, as described above, it is possible to suppress variation in the distance L2 in the radial direction C (see FIG. 5 ) from the laser emitter 20 located in the accommodation space 6 at the position of the inner portion 2a to the expansion member 3, depending on the position in the circumferential direction B. This suppresses variation in the intensity of the laser emitted from the laser emitter 20 located in the accommodation space 6 and emitted outward in the radial direction C from the expansion member 3, or in the intensity of the pressure wave generated by the laser emitted from the laser emitter 20 located in the accommodation space 6 and emitted outward in the radial direction C from the expansion member 3. This makes it possible to improve the efficiency of treatment of a target site, such as a calcified region X, in a blood vessel BV.

[0051] 5, the distal side A1 of the accommodation space 6 in the longitudinal direction A is closed. Specifically, the distal side A1 of the accommodation space 6 is closed by a closing wall 15a. In other words, the distal side A1 of the accommodation space 6 terminates inside the tubular member 2. The closing wall 15a is formed in an area where the inner portion 2a is located in the longitudinal direction A.

[0052] The guidewire insertion hole 7 is formed inside the distal end portion 2b at a position through which the central axis O of the expansion member 3 in the expanded state passes. In other words, the accommodation space 6 and the guidewire insertion hole 7 in this embodiment are provided at positions through which the central axis O of the expansion member 3 in the expanded state passes.

[0053] Specifically, the guidewire insertion hole 7 of this embodiment extends from a distal opening 7a formed on the distal end surface of the distal end 2b of the tubular member 2 to a proximal opening 7b formed on the side surface of the distal end 2b of the tubular member 2 on the proximal side A2 of the distal opening 7a in the longitudinal direction A. In other words, the guidewire GW (see FIG. 1, etc.) can be inserted into the guidewire insertion hole 7 through the distal opening 7a and the proximal opening 7b. The distal opening 7a of the guidewire insertion hole 7 of this embodiment is formed at a position through which the central axis O of the expansion member 3 in an expanded state passes.

[0054] 6 , the guidewire insertion hole 7 of this embodiment includes a main hole 70a extending from the distal opening 7a toward the proximal side A2 in the longitudinal direction A, and an inclined hole 70b connecting the proximal opening 7b and the main hole 70a and extending at an angle with respect to the longitudinal direction A. The main hole 70a of this embodiment is formed at a position through which the central axis O of the expansion member 3 in the expanded state passes. More specifically, the main hole 70a of this embodiment extends in the longitudinal direction A so as to include the central axis O of the expansion member 3 in the expanded state. The inclined hole 70b is inclined with respect to the longitudinal direction A so as to approach the side surface of the distal end portion 2b of the tubular member 2 as it moves toward the proximal side A2.

[0055] The acute inclination angle θ1 of the inclined hole portion 70b with respect to the longitudinal direction A in this embodiment is not particularly limited. However, the inclination angle θ1 of the inclined hole portion 70b with respect to the longitudinal direction A is preferably equal to or greater than the inclination angle θ2 (see FIG. 5 ) of the distal tapered expansion portion 3a2 (described later) of the expansion member 3 with respect to the longitudinal direction A. This prevents the guidewire GW inserted through the guidewire insertion hole 7 from interfering with the expanded expansion member 3. Furthermore, the inclination angle θ1 of the inclined hole portion 70b is preferably equal to or less than 30°. This reduces the force with which the guidewire GW extending from the proximal opening 7b through the inclined hole portion 70b presses against biological tissue, such as the inner wall of the blood vessel BV (see FIG. 1 ), thereby reducing the burden on the biological tissue. The inclination angle θ1 may be the inclination angle of the center line of the inclined hole portion 70b with respect to the longitudinal direction A near the proximal opening 7b.

[0056] As shown in Fig. 5, the tubular member 2 of this embodiment defines a flow path 10 therein, in addition to the above-mentioned storage space 6 and guidewire insertion hole 7. The flow path 10 is used when supplying fluid to the fluid storage space 5 defined by the expansion member 3. Details of the flow path 10 of this embodiment will be described later.

[0057] Next, the tubular body 8 and the distal tip 9 of this embodiment will be described in detail.

[0058] The tubular main body 8 of this embodiment includes an inner tube 11 and an outer tube 12 that surrounds the inner tube 11. The inner tube 11 and the outer tube 12 of this embodiment are arranged so that their respective central axes substantially coincide with the central axis O of the expansion member 3. The storage space 6 of this embodiment is defined inside the inner tube 11. In addition to the storage space 6, the tubular main body 8 defines a flow path 10 inside. The flow path 10 is defined between the inner tube 11 and the outer tube 12.

[0059] More specifically, the inner tube 11 of this embodiment includes a distal protruding portion 11a that protrudes toward the distal side A1 from the outer tube 12, a proximal protruding portion 11b that protrudes toward the proximal side A2 from the outer tube 12, and an intermediate portion 11c that connects the distal protruding portion 11a and the proximal protruding portion 11b and whose outer side in the radial direction C is covered by the outer tube 12. The storage space 6 of this embodiment extends over the distal protruding portion 11a, the proximal protruding portion 11b, and the intermediate portion 11c. The flow path 10 of this embodiment is defined between the intermediate portion 11c of the inner tube 11 and the outer tube 12.

[0060] The expansion member 3 of this embodiment is supported on the outer surface of the tubular member 2. Specifically, the expansion member 3 is supported on the outer surface of the inner tube 11 and the outer surface of the outer tube 12. More specifically, the expansion member 3 of this embodiment is supported across the outer surface of the distal protruding portion 11a of the inner tube 11 and the outer surface of the outer tube main body 12a (described later) of the outer tube 12. As will be described in detail later, the expansion member 3 of this embodiment includes an expansion section 3a that defines a fluid containing space 5 on the inside in the radial direction C and covers the outside of the distal protruding portion 11a of the inner tube 11 in the radial direction C, a distal joint section 3b that is continuous with the distal side A1 of the expansion section 3a and is joined to the outer surface of the distal protruding portion 11a of the inner tube 11, and a proximal joint section 3c that is continuous with the proximal side A2 of the expansion section 3a and is joined to the outer surface of the outer tube main body 12a of the outer tube 12. In other words, the inner portion 2a of the tubular member 2 in this embodiment is the portion of the inner tube 11 and the outer tube 12 that is covered by the expansion portion 3a, distal joint portion 3b, and proximal joint portion 3c of the expansion member 3.

[0061] As shown in FIG. 5 , the proximal protrusion 11b of this embodiment includes a holder 51 that holds the laser emitter 20 inserted into the accommodation space 6 so that the laser emitter 20 is relatively movable in the longitudinal direction A. Specifically, the holder 51 of this embodiment includes an outer tube 51a, a distal wall 51b that closes the distal side A1 of the outer tube 51a, and a proximal wall 51c that closes the proximal side A2 of the outer tube 51a. A through-hole that penetrates the distal wall 51b in the longitudinal direction A is formed in the distal wall 51b. Furthermore, a through-hole that penetrates the proximal wall 51c in the longitudinal direction A is formed in the proximal wall 51c. The laser emitter 20 of this embodiment is movable in the longitudinal direction A relative to the inner tube 11 from a position where a flange 22b1 formed on the inner tube 22b of the connector part 22 abuts against the distal wall 51b in the longitudinal direction A to a position where it abuts against the proximal wall 51c in the longitudinal direction A. By moving the laser emitter 20 within this range in the longitudinal direction A, the laser emission part 23 can be moved in the longitudinal direction A at the position of the inner part 2a.

[0062] In this embodiment, the flow path 10 extends from the fluid supply / discharge port 12b1 formed in the main body 2c of the tubular member 2 to the fluid storage space 5 defined inside the expansion member 3 in the radial direction C. A fluid supply / discharge device such as an indeflator or a syringe can be connected to the fluid supply / discharge port 12b1 via a medical tube or the like. Therefore, a fluid such as a liquid is supplied to the fluid storage space 5 from the fluid supply / discharge device through the flow path 10. When a fluid is supplied to the fluid storage space 5, the expansion member 3 can expand outward in the radial direction C. In contrast, the fluid contained in the fluid storage space 5 is discharged through the flow path 10 to the fluid supply / discharge device. When the fluid is discharged from the fluid storage space 5, the expansion member 3 can contract inward in the radial direction C.

[0063] As described above, the flow path 10 of this embodiment is defined between the inner pipe 11 and the outer pipe 12. Specifically, the flow path 10 of this embodiment is defined between the middle portion 11c of the inner pipe 11 and the outer pipe 12. The fluid supply / discharge port portion 12b1 is formed in the outer pipe 12.

[0064] More specifically, the outer tube 12 of this embodiment includes an outer tube main body 12a and an outer tube hub 12b. The outer tube hub 12b is attached to the proximal side A2 of the outer tube main body 12a. The outer tube hub 12b includes the above-mentioned fluid supply / discharge port 12b1 and proximal end port 12b2. The flow path 10 of this embodiment extends from the fluid supply / discharge port 12b1 of the outer tube hub 12b to the fluid containing space 5.

[0065] The proximal protrusion 11b of the inner tube 11 protrudes from the proximal end opening 12b2 of the outer tube hub 12b toward the proximal side A2. A sealing member 13 made of resin or the like closes the gap between the outer surface of the middle section 11c of the inner tube 11 and the inner surface of the proximal end opening 12b2 of the outer tube hub 12b. The provision of the sealing member 13 prevents fluid such as liquid flowing through the flow channel 10 from leaking from the proximal end opening 12b2.

[0066] 5, the inner portion 2a of the tubular member 2 of this embodiment is provided with radiopaque markers 14a and 14b. The radiopaque markers 14a and 14b may be attached, for example, to the outer surface of the distal protruding portion 11a of the inner tube 11 of the tubular body 8. More specifically, the radiopaque marker 14a is disposed near the distal end of the laser transparent portion 2a1 and the distal end of the window portion 45. The radiopaque marker 14b is disposed near the proximal end of the laser transparent portion 2a1 and the proximal end of the window portion 45. In other words, the radiopaque markers 14a and 14b allow the user to identify the region in the longitudinal direction A where the laser transparent portion 2a1 and the window portion 45 are located. The radiopaque markers 14a and 14b are radiopaque. Specifically, the radiopaque markers 14a and 14b may be formed, for example, from a material that is highly radiopaque. The contrast markers 14a and 14b may be made of a material that is highly opaque to X-rays, such as platinum, gold, iridium, tungsten, etc. The contrast markers 14a and 14b are not limited to having X-ray contrast and may be made of a material that is visible in ultrasound waves, for example.

[0067] The inner tube 11 and the outer tube body 12a of the tubular body 8 of this embodiment are preferably formed of a flexible material, but the material is not particularly limited. Examples of materials for the inner tube 11 and the outer tube body 12a include various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based elastomers, and combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) can also be used.

[0068] The distal tip 9 is connected to the distal end of the tubular body 8 to reduce stress on the biological tissue with which it comes into contact. More specifically, the distal tip 9 is connected to the distal end of the distal protruding portion 11 a of the inner tube 11 of the tubular body 8 by, for example, adhesive bonding or fusion bonding. As described above, the distal tip 9 defines the guidewire insertion hole 7 therein.

[0069] The distal end of the distal tip 9 has a tapered shape that narrows toward the distal end. A distal opening 7a of the guide wire insertion hole 7 is formed on the distal end surface of the distal tip 9.

[0070] The material of the distal tip 9 may be, for example, the same as the material of the inner tube 11. Furthermore, from the viewpoint of reducing the burden on the biological tissue that comes into contact with the distal tip 9, the material of the distal tip 9 may be a material that is more flexible than the material of the inner tube 11. Specific examples of the material of the distal tip 9 include polyamide elastomer, polyester elastomer, polyurethane elastomer, polyolefin elastomer, fluororesin elastomer, and silicone resin.

[0071] Furthermore, a contrast marker having X-ray contrast may be attached to the outer surface of the distal tip 9. However, the contrast marker is not limited to a configuration having X-ray contrast, and may be a configuration having ultrasound visibility, for example.

[0072] Furthermore, when the above-described guidewire insertion hole 7 is defined as the "distal guidewire insertion hole 7," the tubular member 2 may define a proximal guidewire insertion hole 80, as shown in FIG. 5 , through which the guidewire GW inserted through the distal guidewire insertion hole 7 can be inserted at a position on the proximal side A2 in the longitudinal direction A with respect to the expansion member 3. In this embodiment, the outer tube main body 12a of the outer tube 12 of the tubular main body 8 is provided with a protrusion 12a1 that protrudes outward in the radial direction C at the position of the main body portion 2c of the tubular member 2. The proximal guidewire insertion hole 80 that penetrates in the longitudinal direction A is formed in this proximal guidewire insertion hole 80. In this manner, by providing the proximal guidewire insertion hole 80 and inserting the guidewire GW through the distal guidewire insertion hole 7 and the proximal guidewire insertion hole 80, the guidewire GW can be extended along the outer surface of the expansion member 3 in the expanded state. Therefore, the force with which the guidewire GW presses against biological tissue such as the inner wall of the blood vessel BV (see FIG. 1, etc.) can be suppressed, and the burden on the biological tissue can be reduced.

[0073] <Expansion member 3> As described above, the expansion member 3 is supported on the outer surface of the tubular member 2. Specifically, the expansion member 3 of this embodiment is supported across the outer surface of the distal protruding portion 11a of the inner tube 11 and the outer surface of the outer tube 12 so as to straddle the distal end of the outer tube 12 in the longitudinal direction A.

[0074] The expansion member 3 in this embodiment is supported on the outer surface of the tubular member 2 in a state in which it surrounds the outside of the tubular member 2 in the radial direction C. In other words, the expansion member 3 surrounds the outside of the outer surface of the tubular member 2 in the radial direction C over the entire area in the circumferential direction B of the tubular member 2.

[0075] The expansion member 3 is configured to be expandable outward in the radial direction C of the tubular member 2. More specifically, the expansion member 3 of this embodiment is configured as an expandable membrane body attached to the outer surface of the tubular member 2. Both ends in the longitudinal direction A of the expandable membrane body serving as the expansion member 3 are annularly joined to the outer surface of the tubular member 2 by adhesive bonding, fusion, or the like, over the entire circumferential direction B of the tubular member 2. More specifically, the distal end of the expandable membrane body serving as the expansion member 3 is annularly joined to the outer surface of the distal protrusion 11a of the inner tube 11 over the entire circumferential direction B. Furthermore, the proximal end of the expandable membrane body serving as the expansion member 3 is annularly joined to the outer surface of the distal end of the outer tube main body 12a of the outer tube 12 over the entire circumferential direction B. The central portion in the longitudinal direction A of the expandable membrane body serving as the expansion member 3 is not joined to the outer surfaces of the inner tube 11 and the outer tube 12 over the entire circumferential direction B of the tubular member 2, and defines an annular fluid storage space 5 between the expandable membrane body and the outer surface of the tubular member 2. When fluid is supplied to the fluid storage space 5 through the flow path 10 of the tubular member 2 described above, the expandable membrane body serving as the expansion member 3 is pressed by the fluid and expands outward in the radial direction C over the entire circumferential direction B.

[0076] As shown in Figure 2, in a contracted state, the expandable membrane body serving as the expansion member 3 is folded and wrapped around the outer surface of the tubular member 2. When fluid is supplied to the fluid storage space 5, the expandable membrane body serving as the expansion member 3 in the contracted state expands, spreading its folds and protruding outward in the radial direction C of the tubular member 2. As a result, as shown in Figures 3 to 5, the expandable membrane body serving as the expansion member 3 enters an expanded state. Conversely, when fluid is discharged from the fluid storage space 5 by suction or the like, the expanded expansion member 3 enters the contracted state shown in Figures 1 and 2.

[0077] The fluid supplied to the fluid containing space 5 may be a gas or a liquid, and examples thereof include gases such as helium gas, CO2 gas, and O2 gas, and liquids such as saline and contrast medium. Furthermore, as will be described in detail later, the fluid supplied to the fluid containing space 5 may be a liquid that can generate a pressure wave due to the laser emitted from the laser emitter 20.

[0078] In this embodiment, the expansion member 3 is configured as an expandable membrane attached to the outer surface of the tubular member 2, but is not limited to this configuration. The expansion member 3 may also be an annular bag supported on the outer surface of the tubular member 2. In other words, the fluid storage space 5 of the expansion member 3 may be a space defined only by the bag that serves as the expansion member 3. In this way, the expansion member 3 may be configured as a balloon that can be expanded and contracted by a fluid, and the expansion member 3 may be configured as an expandable membrane or a bag.

[0079] More specifically, the expansion member 3 of this embodiment includes an expansion section 3a, a distal joint section 3b, and a proximal joint section 3c. The expansion section 3a is expandable in the radial direction C by fluid supplied to the fluid storage space 5. The expansion section 3a of this embodiment includes a cylindrically expandable expansion main body section 3a1, a distal tapered expansion section 3a2 connected to the distal side A1 of the expansion main body section 3a1 and having an expanded diameter in the expanded state that decreases from the proximal side A2 toward the distal side A1 in the longitudinal direction A, and a proximal tapered expansion section 3a3 connected to the proximal side A2 of the expansion main body section 3a1 and having an expanded diameter in the expanded state that decreases from the distal side A1 toward the proximal side A2 in the longitudinal direction A. The distal joint section 3b is connected to the distal side A1 of the distal tapered expansion section 3a2 of the expansion section 3a and is joined to the outer surface of the tubular member 2. Specifically, the distal joint 3b in this embodiment is joined to the outer surface of the distal protruding portion 11a of the inner tube 11 of the tubular member 2. The proximal joint 3c is continuous with the proximal side A2 of the proximal tapered expansion portion 3a3 of the expansion portion 3a, and is joined to the outer surface of the tubular member 2. Specifically, the proximal joint 3c in this embodiment is joined to the outer surface of the distal end portion of the outer tube body 12a of the outer tube 12 of the tubular member 2.

[0080] The expansion member 3 of this embodiment has a window portion 45 that can release pressure waves caused by the laser emitted from the laser emitter 20 located in the accommodation space 6 outward in the radial direction C. The window portion 45 of this embodiment is the expansion main body portion 3a1.

[0081] The expansion main body portion 3a1 serving as the window portion 45 of the expansion member 3 of this embodiment is provided with a shock wave generating portion 40a capable of generating shock waves as pressure waves by the laser emitted from the laser emitter 20. The shock wave generating portion 40a will be described in detail below.

[0082] As shown in FIG. 5, in the expansion member 3 of this embodiment, the entire expansion main body portion 3a1 is the shock wave generating portion 40a.

[0083] As shown in FIG. 5 , the expansion body portion 3a1 of the expansion member 3 of this embodiment includes a first transparent layer 40a1 and a second transparent layer 40a2 that are transparent to the laser emitted from the laser emitter 20 in the radial direction C, and a light-absorbing layer 40a3 that is located outside the first transparent layer 40a1 and the second transparent layer 40a2 in the radial direction C and is capable of absorbing the laser that has passed through the first transparent layer 40a1 and the second transparent layer 40a2. While the expansion body portion 3a1 of the expansion member 3 of this embodiment includes the first transparent layer 40a1 and the second transparent layer 40a2, this configuration is not limited thereto. The expansion body portion 3a1 of the expansion member 3 may include, for example, only one transparent layer located inward from the light-absorbing layer 40a3 in the radial direction C. Alternatively, the expansion body portion 3a1 of the expansion member 3 may include, for example, three or more transparent layers located inward from the light-absorbing layer 40a3 in the radial direction C.

[0084] Furthermore, in the expansion member 3 of this embodiment, the light absorbing layer 40a3 is the outer surface layer of the expansion main body portion 3a1, but another transparent layer may be laminated on the outer side of the light absorbing layer 40a3 in the radial direction C. However, as in this embodiment, it is preferable that the light absorbing layer 40a3 is the outer surface layer of the expansion main body portion 3a1. In this way, attenuation of laser-induced shock waves due to another transparent layer on the outer side of the light absorbing layer 40a3 in the radial direction C can be suppressed.

[0085] In the expansion main body portion 3a1 of the expansion member 3 of this embodiment, a first transmission layer 40a1, a second transmission layer 40a2, and a light-absorbing layer 40a3 are layered in this order from the inside to the outside in the radial direction C. As a result, as shown in FIG. 7 , the laser emitted from the laser emission portion 23 of the laser emitter 20 housed inside the inner portion 2a of the tubular member 2 passes through the laser transmission portion 2a1, the fluid housed in the fluid storage space 5, and the first transmission layer 40a1 and second transmission layer 40a2 of the expansion main body portion 3a1 of the expansion member 3, and is absorbed by the light-absorbing layer 40a3 of the expansion main body portion 3a1 of the expansion member 3. In the light-absorbing layer 40a3, plasma is generated by the absorbed laser. The plasma generated in the light-absorbing layer 40a3 is easily trapped within the light-absorbing layer 40a3 due to the first transmission layer 40a1 and second transmission layer 40a2 that cover the inside of the light-absorbing layer 40a3 in the radial direction C. This allows laser-induced shock waves to be sent from the light-absorbing layer 40a3 outward in the radial direction C, i.e., toward the outside of the expansion member 3. In other words, the expansion member 3 of this embodiment can emit laser-induced shock waves as pressure waves caused by the laser emitted from the laser emitter 20 outward in the radial direction C. With the catheter 1 of this embodiment, by applying this laser-induced shock wave to the calcified region X in the blood vessel BV, the calcified region X can be fractured.

[0086] Furthermore, the catheter 1 can achieve a state in which the expansion member 3 comes into contact with the calcified region X, which is the target site. Therefore, the above-mentioned laser-induced shock waves can be reliably applied to the calcified region X in the blood vessel BV. In other words, the catheter 1 can ensure the force required for treating the target site by utilizing laser-induced shock waves, and by using the expansion member 3, the laser-induced shock waves can be reliably applied to the target site.

[0087] The first transparent layer 40a1 and the second transparent layer 40a2 of the expansion member 3 may be, for example, transparent resin layers. The second transparent layer 40a2 may be, for example, a base material layer of the expandable membrane body that constitutes the expansion member 3. The first transparent layer 40a1 may be, for example, an inner surface layer that constitutes the inner surface in the radial direction C of the expandable membrane body that constitutes the expansion member 3. The inner surface layer serving as the first transparent layer 40a1 may be arranged to provide protection, flexibility, etc. to the inner surface of the expandable membrane body.

[0088] However, the first transmission layer 40a1 and the second transmission layer 40a2 of the expansion member 3 are not particularly limited in their configuration, as long as they are capable of transmitting the laser irradiated from the laser emitter 20. Examples of materials that can be used to form the first transmission layer 40a1 and the second transmission layer 40a2 include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polyesters such as polyethylene terephthalate, thermoplastic resins such as polyvinyl chloride, ethylene-vinyl acetate copolymers, cross-linked ethylene-vinyl acetate copolymers, and polyurethanes, and polyamides. The total thickness of the one or more transmission layers (the thickness of the two layers, the first transmission layer 40a1 and the second transmission layer 40a2 in this embodiment) can be, for example, 1 to 500 μm. However, the total thickness of the one or more transmission layers is preferably 5 to 100 μm, and more preferably 10 to 50 μm.

[0089] The light absorbing layer 40a3 may be, for example, a black rubber layer, a black resin layer, etc. The light absorbing layer 40a3 is an outer surface layer that forms the outer surface of the expandable membrane body that constitutes the expansion member 3 in the radial direction C.

[0090] However, the light-absorbing layer 40a3 may be configured in any manner that can absorb the laser emitted from the laser emitter 20 and transmitted through the first transmission layer 40a1 and the second transmission layer 40a2, and its configuration is not particularly limited. The light-absorbing layer 40a3 may be configured, for example, from natural rubber or synthetic rubber such as EPDM, nitrile, chloroprene, or neoprene, or from a flexible resin containing a black component such as carbon black, carbon nanotubes, carbon nanohorns, or black perylene pigment. The thickness of the light-absorbing layer 40a3 may be, for example, 1 to 500 μm. However, the thickness of the light-absorbing layer 40a3 is preferably 5 to 100 μm, and more preferably 10 to 50 μm.

[0091] At least one of the first transmission layer 40a1 and the second transmission layer 40a2 and the light absorption layer 40a3 preferably extend over the entire area in the circumferential direction B of the tubular member 2. In this way, laser-induced shock waves can be emitted from the light absorption layer 40a3 outward in the radial direction C over a wider area in the circumferential direction B.

[0092] The shock wave generating unit 40a may be, for example, a liquid contained in the fluid containing space 5. Such a liquid may be, for example, a liquid containing a shock wave generating substance. The shock wave generating substance may be, for example, a metal and / or metal alloy having a relatively high melting temperature, such as tungsten, tantalum, molybdenum, niobium, platinum, and / or iridium. The shock wave generating substance may be, for example, magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, titanium carbide, etc. The shock wave generating substance may be in any form as long as it can be contained together with the liquid in the fluid containing space 5. However, it is preferable that the shock wave generating substance be in the form of fine particles dispersible in the liquid. The fine particles may be, for example, composed solely of the shock wave generating substance. Alternatively, the fine particles may be, for example, a non-shock wave generating substance coated with the shock wave generating substance. Furthermore, the fine particles may be, for example, a mixture of the non-shock wave generating substance and the shock wave generating substance. However, as in this embodiment, the shock wave generating unit 40a is preferably provided in the expansion member 3. In this way, the laser-induced shock waves emitted from the shock wave generator 40a outward in the radial direction C can be applied to the target site, i.e., the calcified region X (see FIG. 1, etc.), without attenuation. The liquid containing the shock wave-generating substance is not limited to the liquid with dispersed fine particles as described above, but may also contain a solution that converts laser light into pressure waves. An example of such a solution is an aqueous solution of indocyanine green and food coloring.

[0093] Furthermore, the shock wave generating section 40a of the expansion member 3 is not limited to the configuration of this embodiment as long as it can generate shock waves using the laser emitted from the laser emitter 20 and emit them outward in the radial direction C.

[0094] The shock wave generating unit 40a may be configured to generate shock waves as pressure waves caused by the laser irradiation and to include a direction changing unit that directs the generated shock waves in a direction different from the laser emission direction. The laser emitted from the laser emission unit 23 toward the shock wave generating unit 40a is irradiated onto the direction changing unit of the shock wave generating unit 40a. The direction changing unit of the shock wave generating unit 40a generates shock waves from the irradiated laser and can emit the generated shock waves in a direction different from the laser emission direction so that they act on the target area. Specifically, the direction changing unit of the shock wave generating unit 40a is positioned opposite the laser emission unit 23 of the laser emitter 20 in the direction of laser emission from the laser emission unit 23. As a result, the laser from the laser emission unit 23 of the laser emitter 20 is irradiated onto the direction changing unit of the shock wave generating unit 40a. The position and shape of the direction changing unit of the shock wave generating unit 40a are adjusted so that the generated shock waves reach the target area. Illustratively, the direction changing section of the shock wave generating section 40a may have an inclined surface that is inclined with respect to the emission direction of the laser so that the laser-induced pressure wave is emitted in a direction perpendicular to the emission direction of the laser from the laser emission section 23 (in the present embodiment, the radial direction C). More specifically, the emission direction of the laser emitted from the laser emission section 23 of the laser emitter 20 is set to the distal side A1 of the longitudinal direction A, and the direction changing section of the shock wave generating section 40a is disposed on the distal side A1 of the laser emission section 23. The direction changing section of the shock wave generating section 40a has an inclined surface that is inclined with respect to the longitudinal direction A. In this manner, shock waves are generated in the direction changing section of the shock wave generating section 40a by the laser irradiated from the laser emission section 23, and the inclined surface of the direction changing section allows the generated shock waves to be emitted outward in the radial direction C toward the target site.

[0095] Furthermore, although the expansion main body portion 3a1 serving as the window portion 45 of the expansion member 3 of this embodiment is capable of emitting shock waves as pressure waves caused by the laser emitted from the laser emitter 20, the configuration is not limited to this. The window portion 45 may be capable of emitting the laser itself emitted from the laser emitter 20 outward in the radial direction C, instead of or in addition to pressure waves caused by the laser emitted from the laser emitter 20. In other words, the catheter according to the present disclosure may be used as a medical device capable of emitting the laser emitted from the laser emitter 23 outward in the radial direction C for treatments such as photodynamic therapy (PDT) and photoimmunotherapy (PIT).

[0096] As shown in FIG. 8, by using a catheter according to the present disclosure as exemplified in this embodiment, a treatment method including the following steps (I) to (III) can be carried out.

[0097] (I) A preparation step S1 of preparing a catheter according to the present disclosure; (II) An expansion step S2 of expanding the expansion member of this catheter at a target site; and (III) A treatment step S3 of emitting a laser from a laser emitter toward a shock wave generating unit capable of generating shock waves as pressure waves by a laser emitted from the laser emitter, and treating the target site with the shock waves generated in the shock wave generating unit.

[0098] In the treatment step S3, the shock waves generated in the shock wave generating section are released from the expansion member, and the shock waves can be reliably applied to the target area that comes into contact with the expansion member.

[0099] The catheter according to the present disclosure is not limited to the specific configurations shown in the above-described embodiments, and various modifications and variations are possible without departing from the scope of the claims.

[0100] The present disclosure relates to catheters.

[0101] 1: Catheter 2: Tubular member 2a: Inner portion 2a1: Laser-transmitting portion 2a2: Light-shielding portion 2b: Distal end portion 2c: Main body portion 3: Expansion member 3a: Expansion portion 3a1: Expansion main body portion 3a2: Distal tapered expansion portion 3a3: Proximal tapered expansion portion 3b: Distal joint portion 3c: Proximal joint portion 5: Fluid containing space 6: Storage space 7: Guidewire insertion hole (an example of a distal guidewire insertion hole) 7a: Distal opening 7b: Proximal opening 8: Tubular main body 9: Distal tip 10: Flow path 11: Inner tube 11a: Distal protruding portion 11b: Proximal protruding portion 11c: Middle portion 12: Outer tube 12a: Outer tube main body 12a1: Protruding portion 12b: Outer tube hub 12b1: Fluid supply / discharge port portion 12b2: Proximal end opening 13: Sealing member 14a, 14b: Radiopaque marker 15a: Closing wall 20: Laser emitter 21: Laser emitter main body 22: Connector portion 22a: Connector main body 22b: Inner cylinder portion 22b1: Flange portion 23: Laser emitter 24: Drive transmission connector 25: Laser non-emission portion 26: Radiopaque marker 31: Laser fiber 32: Fiber coating layer 40a: Shock wave generating portion 40a1: First transmission layer 40a2: Second transmission layer 40a3: Light absorption layer 45: Window portion 51: Retaining portion 51a: Outer cylinder portion 51b: Distal wall portion 51c: Proximal wall portion 70a: Main hole portion 70b: Slanted hole portion 80: Proximal guidewire insertion hole A: Longitudinal direction A1: Distal side A2: Proximal side B: Circumferential direction C: Radial direction BV: Blood vessel GW: Guide wire L1: Irradiation range L2: Radial distance from the laser emitter located in the accommodation space at the position of the inner part to the expansion member O: Central axis of the expansion member X: Calcified region θ1: Inclination angle of the inclined hole portion with respect to the longitudinal direction θ2: Inclination angle of the distal tapered expansion portion of the expansion member with respect to the longitudinal direction

Claims

1. A catheter comprising: a laser emitter capable of emitting a laser; a tubular member defining an internal storage space capable of accommodating the laser emitter and a guidewire insertion hole through which a guidewire can be inserted; an expansion member covering the radial outside of the tubular member and capable of expanding and contracting in the radial direction, wherein the tubular member comprises: an inner portion that is covered by the expansion member on the radial inside of the expansion member and includes a laser transparent portion that is radially transparent to the laser emitted from the laser emitter accommodated in the storage space; and a distal end portion that is connected to the inner portion on the distal side of the longitudinal direction of the tubular member relative to the expansion member, wherein the inner portion of the tubular member does not define the guidewire insertion hole but defines the storage space, and the distal end portion of the tubular member does not define the storage space but defines the guidewire insertion hole.

2. The catheter according to claim 1, wherein the accommodation space extends in the longitudinal direction so as to include a central axis of the expansion member in an expanded state at the position of the inner portion.

3. A catheter as described in claim 1 or 2, wherein the guidewire insertion hole extends from a distal opening formed on the distal end surface of the distal end of the tubular member to a proximal opening formed on the side surface of the distal end of the tubular member, proximal to the distal opening in the longitudinal direction.

4. The catheter according to claim 3, wherein the distal opening of the guide wire insertion hole is formed at a position through which the central axis of the expansion member in an expanded state passes.

5. A catheter as described in claim 3, wherein the guidewire insertion hole comprises: a main hole portion extending from the distal opening to the proximal side in the longitudinal direction; and an inclined hole portion connecting the proximal opening and the main hole portion and extending at an angle with respect to the longitudinal direction.

6. A catheter as described in claim 5, wherein the expansion member comprises: an expansion main body portion that is expandable into a cylindrical shape; and a distal tapered expansion portion that is connected to the distal side of the expansion main body portion and whose expansion diameter decreases from the proximal side toward the distal side in the longitudinal direction, and the inclination angle of the distal tapered expansion portion with respect to the longitudinal direction is equal to or less than the inclination angle of the inclined hole portion of the guide wire insertion hole with respect to the longitudinal direction.

7. The catheter according to claim 1 or 2, wherein the distal side of the accommodating space in the longitudinal direction is closed.

8. A catheter as described in claim 1 or 2, wherein, when the guidewire insertion hole is a distal guidewire insertion hole, the tubular member defines a proximal guidewire insertion hole through which the guidewire inserted in the distal guidewire insertion hole can be inserted at a position proximal to the expansion member in the longitudinal direction.

9. A catheter according to claim 1 or 2, wherein the expansion member is provided with a window portion that can release the laser emitted from the laser emitter or pressure waves caused by the laser outward in the radial direction.

10. A catheter according to claim 9, wherein the window portion of the expansion member is provided with a shock wave generating portion capable of generating shock waves as the pressure waves by the laser emitted from the laser emitter.

11. The catheter according to claim 1 or 2, wherein the inner portion of the tubular member is provided with a marker that is radiopaque or ultrasonically visible.

12. A catheter according to claim 1 or 2, wherein the laser emitter comprises: a laser emitting section in which the laser fiber capable of emitting the laser is not covered with a fiber coating layer; and a non-laser emitting section in which the laser fiber is covered with the fiber coating layer.

Images