WO2025192122A1 - Catheter and catheter set - Google Patents

Abstract

A catheter according to the present disclosure comprises: a tubular member that partitions an accommodation space in which a laser emitter can be accommodated; and an expansion member that covers the outside of the tubular member in the radial direction and can expand and contract in the radial direction. The tubular member can transmit a laser, emitted from the laser emitter accommodated in the accommodation space, in the radial direction while at a position covered by the expansion member. The expansion member comprises: a transmission layer that can transmit, in the radial direction, a laser emitted from the laser emitter accommodated in the accommodation space; and a light absorption layer that is positioned outside the transmission layer in the radial direction and can absorb the laser transmitted through the transmission layer.

Description

Catheters and catheter sets

This disclosure relates to catheters and catheter sets.

Probes that convert laser light into shock waves and utilize the shock wave stress to perform various treatments have been known for some time. 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.

Japanese Patent Application Publication No. 5-300911 Special Publication No. 2015-522344

However, the probes described in Patent Documents 1 and 2 still have room for improvement in terms of the efficiency with which the force required for treatment can be reliably applied to the target site when treating the target site, such as crushing a calcified area within a blood vessel.

The present disclosure aims to provide a catheter and catheter set that can improve efficiency when treating a target area.

A catheter according to a first aspect of the present disclosure includes:
(1)
a tubular member defining an accommodation space therein capable of accommodating a laser emitter;
an expansion member that covers the radial outside of the tubular member and is capable of expanding and contracting in the radial direction,
the tubular member is capable of transmitting, in the radial direction, a laser emitted from the laser emitter accommodated in the accommodation space at a position where the tubular member is covered by the expansion member,
The expansion member is
a transmission layer that allows the laser emitted from the laser emitter accommodated in the accommodation space to transmit in the radial direction;
a light-absorbing layer positioned radially outward of the transmission layer and capable of absorbing the laser that has passed through the transmission layer.

According to one embodiment of the present disclosure, a catheter includes:
(2)
The tubular member is provided at a position where it is covered by the expansion member.
a transmission portion that allows the laser emitted from the laser emitter accommodated in the accommodation space to transmit in the radial direction;
a light-shielding portion having a lower transmittance of the laser than the light-transmitting portion,
The catheter according to (1) above, wherein the light-transmitting portions and the light-blocking portions are alternately formed along the axial direction of the tubular member.

According to one embodiment of the present disclosure, a catheter includes:
(3)
a plurality of the transmission portions are arranged intermittently in the axial direction,
The catheter according to (2) above, wherein the light-shielding portion is disposed between the plurality of transmitting portions in the axial direction.

A catheter set according to a second aspect of the present disclosure includes:
(4)
The catheter according to any one of (1) to (3) above,
and a catheter set comprising the laser emitter.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(5)
The laser emitter is
a drive shaft that is movable in the axial direction of the tubular member within the accommodation space of the tubular member;
a laser emitter carried on a distal end of the drive shaft;
an optical transmission line extending inside the drive shaft and optically connected to the laser emission unit;
The catheter set according to (4) above, wherein the optical transmission line is configured to be capable of transmitting lasers of different power outputs.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(6)
The laser emitter is
A guidewire body;
a laser emission unit held by the guidewire body;
An optical transmission line extending along the longitudinal direction of the guidewire body and optically connected to the laser emission unit.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(7)
The laser emitter is
a tubular body defining a guidewire insertion space therein through which a guidewire can be inserted;
a laser emission unit held on a side wall of the tube;
The catheter set according to (4) above further comprises an optical transmission line extending along the longitudinal direction of the tubular body and optically connected to the laser emission unit.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(8)
The catheter set described in (7) above, wherein a slit is formed in the side wall of the tubular body, penetrating from the outer surface to the inner surface and extending along the longitudinal direction from the distal end of the tubular body.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(9)
The catheter is the catheter set described in (4) above, which includes a guidewire insertion portion defining a guidewire insertion hole therein through which a guidewire can be inserted.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(10)
the guidewire insertion portion includes an inner extending portion that extends along the axial direction of the tubular member, inside the radial direction of the expansion member,
The catheter set is described in (9) above, wherein the inner extension portion is capable of transmitting the laser emitted from the laser emitter housed in the housing space of the tubular member in the radial direction.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(11)
The catheter set described in (9) above is such that the guide wire insertion portion is located only distal to the expansion member, and the proximal end of the guide wire insertion portion is fixed to the distal end of the tubular member.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(12)
The catheter set according to (11) above, wherein the storage space of the tubular member is closed at the distal end.

According to one embodiment of the present disclosure, there is provided a catheter set comprising:
(13)
the laser emitter is movable within the accommodation space of the tubular member in an axial direction of the tubular member,
The catheter set is described in any one of (4) to (12) above, wherein the tubular member and the laser emitter are provided with a resistance mechanism that makes the resistance force when the laser emitter moves distally in the axial direction relative to the tubular member greater than the resistance force when the laser emitter moves proximally in the axial direction relative to the tubular member.

The present disclosure provides a catheter and catheter set that can improve the efficiency of treating a target area.

FIG. 1 illustrates a catheter set according to an embodiment of the present disclosure, including a catheter according to an embodiment of the present disclosure. 2 is a cross-sectional view of the catheter set shown in FIG. 1 taken along a plane parallel to the central axis of the tubular member of the catheter. FIG. 2 is a cross-sectional view of the catheter set taken along line I-I in FIG. 1. 2 is a diagram showing a state in which an expansion member of the catheter of the catheter set shown in FIG. 1 is expanded. FIG. 5 is a cross-sectional view of the catheter set shown in FIG. 4 at the same position as FIG. 2. 5 is a cross-sectional view of the catheter set shown in FIG. 4 at the same position as FIG. 3. FIG. 1 is an explanatory diagram for explaining the principle of generation of laser-induced shock waves. FIG. 10 is a diagram showing a modified example of the catheter set shown in FIG. 1, showing the contracted state of the expansion member of the catheter. 8B is a diagram showing the expanded state of the expansion member of the catheter in the catheter set shown in FIG. 8A. FIG. FIG. 10 is a diagram showing a modified example of the catheter set shown in FIG. 1, showing the contracted state of the expansion member of the catheter. 9B is a diagram showing the expanded state of the expansion member of the catheter in the catheter set shown in FIG. 9A. FIG. 2 is a diagram showing a catheter set including a laser emitter as a modified example of the laser emitter shown in FIG. 1. FIG. FIG. 2 is a diagram showing a catheter set including a laser emitter as another modified example of the laser emitter shown in FIG. 1 . FIG. 10 is a diagram showing a catheter set including a laser emitter as yet another modified example of the laser emitter shown in FIG. 1 . FIG. 12B is a cross-sectional view taken along line II-II in FIG. 12A. FIG. 1 is a cross-sectional view of a catheter set according to an embodiment of the present disclosure, including a catheter according to an embodiment of the present disclosure. FIG. 14 shows a resistance mechanism of the catheter set shown in FIG. 13. 14B is a diagram showing a state in which the resistance mechanism shown in FIG. 14A has changed in shape. FIG. FIG. 14B shows a modification of the resistance mechanism shown in FIG. 14A. 15B is a diagram showing a state in which the resistance mechanism shown in FIG. 15A has changed in shape. FIG. FIG. 1 is a cross-sectional view of an optical transmission line of a laser emitter in a catheter set according to an embodiment of the present disclosure. FIG. 17 is a cross-sectional view of a catheter set including a laser emitter with the optical transmission line shown in FIG. 16. 18 is a diagram showing an example of a procedure performed using the catheter set shown in FIG. 17, and shows the state after treatment of the target site with a treatment laser has been completed from the state shown in FIG. 17. FIG. 18 is a diagram showing an example of a procedure performed using the catheter set shown in FIG. 17, showing a state in which the laser emitter has been returned from the position shown in FIG. 18 to the position shown in FIG. 17. FIG. 19 shows an example of a procedure performed using the catheter set shown in FIG. 17, and shows the state after the completion of transmission and reception of diagnostic laser light in order to obtain a diagnostic image of the target area after treatment, from the state shown in FIG. 19.

Embodiments of a catheter and catheter set according to the present disclosure will be illustrated and described below with reference to the drawings. The same components are designated by the same reference numerals in each drawing.

[First embodiment]
1 is a diagram showing a catheter set 100 as an embodiment of a catheter set according to the present disclosure, including a catheter 1 as an embodiment of a catheter according to the present disclosure. The catheter set 100 includes the catheter 1 and a laser emitter 20 that can be housed within the catheter 1.

FIG. 1 shows the catheter 1 and laser emitter 20 inserted into a blood vessel BV. FIG. 1 also shows the laser emitter 20 housed within the catheter 1. The catheter set 100 is a medical instrument set in which the catheter 1 and laser emitter 20 are inserted into the blood vessel BV and the catheter set 100 is capable of fracturing a calcified region X within the blood vessel BV by utilizing shock waves generated by laser irradiation. In this embodiment, the calcified region X within the blood vessel BV is exemplified as the target site to be treated with the catheter set 100, but the catheter set 100 may also be used to treat other target sites.

As shown in Figure 1, the catheter 1 of this embodiment comprises a tubular member 2, an expansion member 3, and a hub 4. Figure 1 shows the catheter 1 percutaneously inserted into a patient's blood vessel BV, with the expansion member 3 introduced up to the position of the lesion, which is the target site where a calcified region X has formed. Figure 1 also shows the expansion member 3 in a contracted state. In the contracted state, the expansion member 3 is transported within the blood vessel BV to the lesion.

Hereinafter, in the catheter 1 and the catheter set 100, the axial direction of the tubular member 2 parallel to the central axis O of the tubular member 2 will be referred to as the "axial direction A." The distal side of the axial direction A may be simply referred to as the "distal direction A1." The proximal side of the axial direction A may be referred to as the "proximal direction A2." Furthermore, in the catheter 1 and the catheter set 100, the circumferential direction of the tubular member 2 around the central axis O of the tubular member 2 will be referred to as the "circumferential direction B." Furthermore, in the catheter 1 and the catheter set 100, the radial direction of the tubular member 2, which is the radial direction of an imaginary circle centered on the central axis O in any cross section perpendicular to the central axis O of the tubular member 2, will be referred to as the "radial direction C."

Figures 2 and 3 are cross-sectional views of the catheter set 100 shown in Figure 1. Figure 2 is a cross-sectional view of the catheter set 100 taken along a plane that includes the central axis O and is parallel to the central axis O. Also, Figure 2 shows only the distal end of the catheter set 100 (hereinafter referred to as the "distal end"). Figure 3 is a cross-sectional view of the catheter set 100 taken along line I-I in Figure 1.

Figures 4 to 6 show the expanded state of the expansion member 3 shown in Figures 1 to 3 in the contracted state. Specifically, Figure 4 shows the expanded state of the expansion member 3 shown in Figure 1 in the contracted state within the blood vessel BV. Figure 5 is a cross-sectional view at the same position as Figure 2, showing the expansion member 3 in the expanded state. Figure 6 is a cross-sectional view at the same position as Figure 3, showing the expansion member 3 in the expanded state.

As shown in Figures 1 to 6, the tubular member 2 defines an internal storage space 2a capable of storing the laser emitter 20. The expansion member 3 covers the outside of the tubular member 2 in the radial direction C. The expansion member 3 is capable of expanding and contracting in the radial direction C. In this embodiment, the expansion member 3 is supported on the outer surface of the tubular member 2.

At the position covered by the expansion member 3, the tubular member 2 is capable of transmitting the laser emitted from the laser emitter 20 housed in the storage space 2a in the radial direction C. The tubular member 2 may be configured to be capable of transmitting the laser emitted from the laser emitter 20 housed in the storage space 2a in the radial direction C over the entire area in the axial direction A at the position covered by the expansion member 3. In other words, the tubular member 2 may be configured to be capable of transmitting the laser emitted from the laser emitter 20 housed in the storage space 2a in the radial direction C only over a partial area in the axial direction A at the position covered by the expansion member 3.

More specifically, the tubular member 2 of this embodiment includes a transparent portion 41 that allows the laser emitted from the laser emitter 20 housed in the housing space 2a to pass through in the radial direction C, and a light-shielding portion 42 that has low transmittance in the radial direction C of the laser emitted from the laser emitter 20 through the transparent portion 41. The transparent portion 41 may be made of, for example, a light-transmitting material that has high transmittance of the laser emitted from the laser emitter 20. The light-shielding portion 42 may be made by covering the light-transmitting material that makes up the transparent portion 41 with a light-shielding material that has low transmittance of the laser emitted from the laser emitter 20. As shown in Figures 2 and 5, the tubular member 2 of this embodiment includes a transparent portion 41 at a position that is covered by the expansion member 3. As shown in Figures 2 and 5, the tubular member 2 of this embodiment includes a light-shielding portion 42 over the entire area distal and proximal to the transparent portion 41 in the axial direction A.

6, the expansion member 3 comprises a first transmission layer 3a and a second transmission layer 3b that are transmissive in the radial direction C to the laser emitted from the laser emitter 20 housed in the housing space 2a of the tubular member 2, and a light-absorbing layer 3c that is located outside the first transmission layer 3a and the second transmission layer 3b in the radial direction C and is capable of absorbing the laser that has passed through the first transmission layer 3a and the second transmission layer 3b. While the expansion member 3 of this embodiment comprises the first transmission layer 3a and the second transmission layer 3b, this configuration is not limited to this. The expansion member 3 may comprise, for example, only one transmission layer inside the light-absorbing layer 3c in the radial direction C. The expansion member 3 may also comprise, for example, three or more transmission layers inside the light-absorbing layer 3c in the radial direction C. The expansion member 3 may also comprise, for example, only one transmission layer inside the light-absorbing layer 3c in the radial direction C. The extension member 3 may also include a light-shielding layer that is opaque to the laser emitted from the laser emitter 20 and that is located in only a portion of the axial direction A of the extension member 3, for example, inward in the radial direction C from the light-absorbing layer 3c. The light-shielding layer may be provided, for example, in a position in the axial direction A where it is desired to suppress the transmission of laser-induced shock waves outward in the radial direction C.

Furthermore, in the expansion member 3 of this embodiment, the light-absorbing layer 3c is the outer surface layer of the expansion member 3, but a separate transparent layer may be laminated on the outer side of it in the radial direction C. However, as in this embodiment, it is preferable that the light-absorbing layer 3c is the outer surface layer of the expansion member 3. By doing so, it is possible to suppress attenuation of laser-induced shock waves due to a separate transparent layer on the outer side of the light-absorbing layer 3c in the radial direction C.

The laser emitted from the laser emitter 20 passes through the tubular member 2 of the catheter 1 in the radial direction C and is irradiated onto the expansion member 3 of the catheter 1. The laser irradiated onto the expansion member 3 passes through the first transmission layer 3a and second transmission layer 3b of the expansion member 3 and is absorbed by the light-absorbing layer 3c. Plasma is generated in the light-absorbing layer 3c by the absorbed laser. The plasma generated in the light-absorbing layer 3c is more likely to remain within the light-absorbing layer 3c due to the first transmission layer 3a and second transmission layer 3b that cover the inside of the light-absorbing layer 3c in the radial direction C. This allows laser-induced shock waves to be sent from the light-absorbing layer 3c toward the outside in the radial direction C. In the catheter set 100, by applying this laser-induced shock wave to a calcified region X in the blood vessel BV, the calcified region X can be fractured.

Furthermore, with the catheter 1, it is possible to achieve a state in which the expansion member 3 comes into contact with the calcified region X, which is the target site. This allows the above-mentioned laser-induced shock waves to be reliably applied to the calcified region X within the blood vessel BV. In other words, with the catheter 1, the force required to treat the target site is secured by utilizing laser-induced shock waves, and by using the expansion member 3, this laser-induced shock wave is reliably applied to the target site, thereby improving the efficiency of treating the target site.

The laser emitter 20 need only be capable of emitting a laser capable of generating laser-induced shock waves in the light absorption layer 3c of the expansion member 3 of the catheter 1, and can be configured to emit, for example, a nanosecond pulse laser, a picosecond laser, a femtosecond pulse laser, etc.

As described above, the transparent portion 41 is provided in the covered portion 2c, which is the portion of the tubular member 2 whose periphery in the radial direction C is covered by the expansion member 3. In contrast, the light-shielding portion 42 is provided in the exposed portion 2d, which is the portion of the tubular member 2 whose periphery in the radial direction C is not covered by the expansion member 3. The light-transmitting material constituting the transparent portion 41 is not particularly limited as long as it is a material that can transmit the laser from the laser emitter 20, but examples 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 thereof), polyvinyl chloride, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, polyimide, fluororesin, or a mixture thereof. The transparent portion 41 may be transparent in the radial direction C, for example. As described above, the light-shielding portion 42 in this embodiment is formed by covering the light-transmitting material constituting the transparent portion 41 with a light-shielding material. The light-shielding material used for the light-shielding portion 42 is not particularly limited as long as it has a lower transmittance for the laser from the laser emitter 20 than the light-transmitting material that makes up the above-mentioned transmitting portion 41. Examples of light-shielding materials that can be used include various metal materials such as titanium oxide, barium sulfate, zinc oxide, silver, and aluminum. The light-shielding material may also be a resin containing particles of the above-mentioned metal materials or carbon black.

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

However, the first transmission layer 3a and second transmission layer 3b 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 3a and second transmission layer 3b include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyesters such as polyethylene terephthalate; thermoplastic resins such as polyvinyl chloride, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate copolymer, and polyurethane; and polyamides. The total thickness of the one or more transmission layers (the thickness of the two layers, the first transmission layer 3a and the second transmission layer 3b 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.

The light-absorbing layer 3c may be, for example, a black rubber layer, a black resin layer, etc. The light-absorbing layer 3c 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.

However, the light-absorbing layer 3c is not particularly limited in its configuration, as long as it is capable of absorbing the laser emitted from the laser emitter 20 and transmitted through the first and second transmission layers 3a and 3b. The light-absorbing layer 3c may be made of, for example, black rubber such as natural rubber or synthetic rubber EPDM, nitrile, chloroprene, or neoprene, or a flexible resin containing a black component such as carbon black or black perylene pigment. The thickness of the light-absorbing layer 3c can be, for example, 1 to 500 μm. However, the thickness of the light-absorbing layer 3c is preferably 5 to 100 μm, and more preferably 10 to 50 μm.

The catheter 1 and laser emitter 20 of this embodiment are described in detail below.

<Catheter 1>
<<Tubular member 2>>
1 and 4, the tubular member 2 is percutaneously inserted into the patient's blood vessel BV from its distal end. A hub 4 is connected to the proximal end of the tubular member 2.

In this embodiment, the tubular member 2 supports the expansion member 3. More specifically, the tubular member 2 supports the expansion member 3 at its distal end. In addition to the storage space 2a capable of accommodating the laser emitter 20, the tubular member 2 defines an internal flow path 2b that can supply fluid to the fluid storage space 5 defined by the expansion member 3. The fluid supplied to the fluid storage space 5 of the expansion member 3 can be removed through the flow path 2b by suction or the like. The flow path 2b extends from the proximal end of the tubular member 2 connected to the hub 4 (hereinafter referred to as the "proximal end") to the position in the axial direction A where the expansion member 3 is provided. The proximal end of the flow path 2b is connected to the internal flow path of the hub 4. As shown in Figures 2 and 5, the distal end of the flow path 2b is connected to the fluid storage space 5.

In this embodiment, the storage space 2a of the tubular member 2 penetrates from the distal end to the proximal end of the tubular member 2. The laser emitter 20 is inserted into the storage space 2a from the proximal end of the tubular member 2 in the distal direction A1. The laser emitter 20 is inserted into the storage space 2a so that the laser emitter 21, which will be described later, reaches a position where it is covered by the expansion member 3. In other words, the laser emitter 20 is inserted into the storage space 2a so that the laser emitter 21 reaches the position of the covered portion 2c of the tubular member 2. As described above, the covered portion 2c is provided with a transparent portion 41. Therefore, the laser emitted from the laser emitter 21 of the laser emitter 20 passes through the transparent portion 41 in the covered portion 2c of the tubular member 2 to the outside in the radial direction C and reaches the expansion member 3.

In this embodiment, the storage space 2a is used not only to store the laser emitter 20 described above, but also to insert a guidewire GW (see Figure 8A, etc.). That is, the storage space 2a in this embodiment also serves as a guidewire insertion hole. The tubular member 2 is guided through the blood vessel BV along the guidewire GW inserted into the storage space 2a. Then, when the tubular member 2 reaches the calcified region X as the target site within the blood vessel BV, the laser emitter 20 is inserted into the storage space 2a instead of the guidewire GW. Then, a procedure is performed to crush the calcified region X.

More specifically, the tubular member 2 of this embodiment comprises an inner tube 11 that defines a storage space 2a that also serves as a guidewire insertion hole, and an outer tube 12 that covers the outside of the inner tube 11 in the radial direction C and is arranged concentrically with the inner tube 11. The inner tube 11 is arranged to protrude further in the distal direction A1 than the distal end of the outer tube 12. A marker member 13 is attached to the distal end of the inner tube 11. The marker member 13 has radiopaque properties. Specifically, the marker member 13 is formed from a material that is highly radiopaque. Specifically, the marker member 13 can be made of a material that is highly radiopaque, such as platinum, gold, iridium, or tungsten. The flow path 2b of this embodiment is defined between the outer surface of the inner tube 11 and the inner surface of the outer tube 12. The flow path 2b is connected to the fluid storage space 5 at the distal end of the outer tube 12. However, the configuration of the tubular member 2 is not limited to that of this embodiment. The tubular member 2 of this embodiment is realized by forming the storage space 2a and the flow path 2b into a double-pipe structure, but the means for realizing the storage space 2a and the flow path 2b are not limited to a double-pipe structure.

The transparent portion 41 of the tubular member 2 of this embodiment is formed in the inner tube 11. More specifically, the transparent portion 41 of the tubular member 2 of this embodiment is formed in the portion of the inner tube 11 that protrudes in the distal direction A1 from the outer tube 12. The light-shielding portion 42 of the tubular member 2 of this embodiment is formed by the remaining portion of the inner tube 11 where the transparent portion 41 is not formed, and the entire outer tube 12, but is not limited to this configuration.

As described above, the catheter 1 of this embodiment is configured so that the storage space 2a of the tubular member 2 also serves as a guidewire insertion hole, but this configuration is not limited to this. As shown in Figures 8A, 8B, 9A, and 9B, the catheter 1 may further include a guidewire insertion portion 6 that defines a guidewire insertion hole 6a therein, through which a guidewire GW can be inserted. The guidewire insertion portion 6 shown in Figures 8A and 8B is positioned so that it is parallel to the distal end of the tubular member 2 that defines the storage space 2a. The guidewire insertion portion 6 shown in Figures 8A and 8B is positioned only distal to the expansion member 3. The proximal end portion 6a1 of the guidewire insertion portion 6 shown in Figures 8A and 8B is fixed to the distal end portion 11b of the inner tube 11, which serves as the distal end portion of the tubular member 2. The tubular member 2 and guidewire insertion section 6 shown in Figures 8A and 8B can be formed by joining different tubular bodies together by heat fusion or the like, but are not limited to this method of formation.

In the catheter 1 of this embodiment, the space within the inner tube 11 serving as the storage space 2a of the tubular member 2 may be liquid-tightly sealed at the distal end 11b. With such a configuration, the storage space 2a does not communicate with the blood vessel BV, preventing blood from entering the storage space 2a into which the laser emitter 20 is inserted, thereby preventing attenuation of the laser emitted from the laser emitter 20. This eliminates the need for a procedure to remove blood that has entered the storage space 2a, thereby shortening the procedure time.

Furthermore, the guidewire insertion portion 6 shown in Figures 9A and 9B is positioned so as to be parallel to the distal end of the tubular member 2 that defines the storage space 2a. Furthermore, the guidewire insertion portion 6 shown in Figures 9A and 9B has an inner extending portion 6b that extends along the axial direction A inside the radial direction C of the expansion member 3. The inner extending portion 6b is capable of transmitting, in the radial direction C, the laser emitted from the laser emitter 20 contained in the storage space 2a of the tubular member 2. In this way, the guidewire insertion portion 6 may be configured to have an inner extending portion 6b. The inner extending portion 6b may be formed, for example, from the same constituent material as the transparent portion 41 of the tubular member 2 described above.

<<Extension member 3>>
2 and 5 , 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 on both the outer surface of the inner tube 11 and the outer surface of the outer tube 12. The expansion member 3 of this embodiment surrounds the outside of the tubular member 2 in the radial direction C over the entire area in the circumferential direction B.

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 in this embodiment is configured as an expandable membrane body attached to the outer surface of the tubular member 2. Both ends in the axial 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, etc., 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 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 outer tube 12 over the entire circumferential direction B. The central portion in the axial 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 outer tube 12 over the entire circumferential direction B of the tubular member 2, and defines an annular fluid storage space 5 between it and the outer surface of the tubular member 2. When fluid is supplied to the fluid storage space 5 through the flow path 2b 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 of the tubular member 2 over the entire circumferential direction B of the tubular member 2.

As shown in Figure 3, 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 the folds and protruding outward in the radial direction C of the tubular member 2. As a result, as shown in Figure 6, the expandable membrane body serving as the expansion member 3 enters an expanded state. Conversely, when fluid is sucked from the fluid storage space 5, the expanded expansion member 3 enters the contracted state shown in Figure 3.

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, CO ₂ gas, and O ₂ gas, and liquids such as saline and contrast medium.

In this embodiment, the expansion member 3 is composed of 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 serving as the expansion member 3. As such, the expansion member 3 may be composed of either an expandable membrane or a bag as long as it is capable of forming a balloon that can be expanded and contracted by a fluid. However, when the expansion member 3 is composed of a bag, the membrane portion on the inside of the radial direction C of the bag constituting the expansion member 3 is interposed between the laser emission section 21 (described later) of the laser emitter 20 and the membrane portion on the outside of the radial direction C of the bag constituting the expansion member 3. Therefore, the membrane portion on the inside of the radial direction C of the bag constituting the expansion member 3 needs to be configured to be laser-transparent. This allows the laser emitted from the laser emission unit 21 to reach the membrane portion of the bag that constitutes the expansion member 3 on the outer side in the radial direction C. Therefore, from the perspective of simplifying the configuration of the expansion member 3, it is preferable that the expansion member 3 be composed of an expandable membrane body, as in this embodiment.

6, the expansion member 3 of this embodiment includes the first transmission layer 3a, second transmission layer 3b, and light absorption layer 3c described above. In this embodiment, the first transmission layer 3a, second transmission layer 3b, and light absorption layer 3c 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 section 21 of the laser emitter 20 contained in the storage space 2a of the tubular member 2 described above passes through the transmission section 41 of the tubular member 2, the fluid contained in the fluid storage space 5, and the first transmission layer 3a and second transmission layer 3b of the expansion member 3, and is absorbed by the light absorption layer 3c of the expansion member 3. In the light absorption layer 3c, plasma is generated by the absorbed laser. The plasma generated in the light absorption layer 3c is more likely to remain within the light absorption layer 3c due to the first transmission layer 3a and second transmission layer 3b covering the inside of the light absorption layer 3c in the radial direction C. This allows laser-induced shock waves to be sent from the light-absorbing layer 3c outward in the radial direction C, i.e., toward the outside of the expansion member 3. In the catheter set 100 of this embodiment, by applying this laser-induced shock wave to the calcified region X within the blood vessel BV, the calcified region X can be fractured.

For this reason, it is preferable that at least one of the first and second transparent layers 3a and 3b, and the light-absorbing layer 3c, extend over the entire circumferential direction B of the tubular member 2. This allows laser-induced shock waves to be sent from the light-absorbing layer 3c outward in the radial direction C over a wider range in the circumferential direction B.

Furthermore, as in this embodiment, the expansion member 3 is provided with at least one transparent layer (two transparent layers, the first transparent layer 3a and the second transparent layer 3b, in this embodiment) and a light absorbing layer 3c, so that the laser-induced shock waves sent outward in the radial direction C from the light absorbing layer 3c can act on the calcified region X (see Figure 1, etc.) without attenuation, compared to a configuration in which the transparent layer and the light absorbing layer are provided on the tubular member 2.

<< Hub 4 >>
As shown in Figures 1 and 4, the tubular member 2 is connected to the distal side of the hub 4. A hub internal flow path that communicates with the flow path 2b of the tubular member 2 is defined within the hub 4. Fluid can be supplied to the flow path 2b of the tubular member 2 from a connector portion 4a provided on the proximal side of the hub 4 through the hub internal flow path. In addition, a hub internal insertion hole that communicates with the accommodation space 2a of the tubular member 2 is defined within the hub 4. The guidewire GW (see Figure 8A, etc.) and the laser emitter 20 can be inserted from a proximal opening 4b, which is the proximal end of the hub internal insertion hole provided on the proximal side of the hub 4, through the hub internal insertion hole and into the accommodation space 2a of the tubular member 2.

<Laser emitter 20>
1 to 6 , the laser emitter 20 is configured to be able to be housed in the housing space 2a of the tubular member 2. More specifically, the laser emitter 20 of this embodiment is able to be housed in the housing space 2a inside the inner tube 11 of the tubular member 2.

As shown in Figures 2 and 5, the laser emitter 20 of this embodiment comprises a laser emitter 21, an optical transmission line 22, and a drive shaft 23. The drive shaft 23 is movable in the axial direction A within the storage space 2a of the tubular member 2. The drive shaft 23 of this embodiment is also rotatable in the circumferential direction B within the storage space 2a of the tubular member 2. The laser emitter 21 is held at the distal end of the drive shaft 23. The laser emitter 21 is capable of emitting a laser in the radial direction C. The optical transmission line 22 extends inside the drive shaft 23 and is optically connected to the laser emitter 21.

In the laser emitter 20 of this embodiment, the laser emitter 21 is positioned coaxially with the storage space 2a within the inner tube 11 of the tubular member 2. As a result, when the expansion member 3 is expanded, the distance from the laser emitter 21 to the light-absorbing layer 3c is substantially the same in the circumferential direction B, so the intensity of the laser-induced shock waves sent from the light-absorbing layer 3c outward in the radial direction C can be made substantially the same in the circumferential direction B, allowing the laser-induced shock waves to act approximately equally around the entire circumference of the calcified region X within the blood vessel BV.

As shown in Figure 5, the laser emitter 20 including the laser emission unit 21, when housed in the storage space 2a, can emit laser outward in the radial direction C from a partial position in the circumferential direction B. Therefore, by rotating the laser emitter 20 in the circumferential direction B within the storage space 2a of the tubular member 2, the laser emitted from the laser emission unit 21 can be emitted over the entire area in the circumferential direction B. Furthermore, by moving the laser emitter 20 in the axial direction A within the storage space 2a of the tubular member 2, the laser emitted from the laser emission unit 21 can be emitted over the entire area in the axial direction A where the expansion member 3 is located. In this way, by moving the laser emitter 20 in the axial direction A and rotating it in the circumferential direction B within the storage space 2a, it is possible to apply laser-induced shock waves in accordance with the size and position of the calcified area X within the blood vessel BV. The irradiation range L1 (see Figure 7) in the circumferential direction B of the light absorption layer 3c of the expansion member 3, onto which the laser from the laser emission unit 21 of the laser emitter 20 is irradiated, may be set as appropriate.

The laser emitter 20 may, for example, be provided with multiple laser emitters 21 spaced apart in the axial direction A. By configuring the laser emitter 20 to have multiple laser emitters 21 at different positions in the axial direction A, the treatment of transmitting laser-induced shock waves toward the calcified region X can be carried out by moving the laser emitter 20 only in the circumferential direction B within the accommodation space 2a. The laser emitter 20 may also be provided with a laser emitter 21 that is long in the axial direction A and can emit a wide laser beam of uniform intensity in the radial direction C regardless of the position in the axial direction A. In such cases, it is not necessary to arrange multiple laser emitters 20 in the axial direction A.

Furthermore, the laser emitter 20 may be provided with multiple laser emitters 21 spaced apart in the circumferential direction B, for example. By configuring the laser emitter 20 to have multiple laser emitters 21 at different positions in the circumferential direction B, the treatment of transmitting laser-induced shock waves toward the calcified region X can be carried out by moving the laser emitter 20 only in the axial direction A within the accommodation space 2a. However, the laser emitter 20 may also be provided with a laser emitter 21 of an all-around irradiation type, such as a radial fiber. With an all-around irradiation laser emitter 21, laser can be emitted radially throughout the entire area in the circumferential direction B. In such cases, it is not necessary to arrange multiple laser emitters 20 in the circumferential direction B.

In this way, the laser emitter 20 may have only one laser emitter 21, or may have multiple laser emitters 21.

The optical transmission line 22 includes an optical fiber that transmits light to the laser emission unit 21. In this embodiment, the optical transmission line 22 extends inside the drive shaft 23, but this arrangement is not limited to this. For example, the optical transmission line 22 may be configured to extend outside the drive shaft 23 and along the drive shaft 23 within the accommodation space 2a.

The drive shaft 23 may be made of a flexible tube. For example, the drive shaft 23 may be made of multiple layers of coils wound in different directions around the axis. Examples of coil materials include stainless steel and Ni-Ti (nickel-titanium) alloy.

As shown in Figures 1 and 4, the drive shaft 23 is exposed in the proximal direction A2 from the proximal opening 4b of the hub 4, with the laser emission unit 21 positioned so that it is covered by the expansion member 3. Therefore, by operating the portion of the drive shaft 23 that is exposed proximally from the hub 4, the laser emitter 20 can move in the axial direction A and rotate in the circumferential direction B within the accommodation space 2a. The movement of the drive shaft 23 in the axial direction A and the rotation in the circumferential direction B may be performed manually by a user such as a surgeon, or may be performed by, for example, a drive device connectable to the drive shaft 23.

As described above, the laser emitter 20 of the catheter set 100 of this embodiment is configured to include the laser emitter 21, optical transmission line 22, and drive shaft 23 described above, but is not limited to this configuration.

10 is a diagram showing a catheter set 200 including a laser emitter 120 as a modified example of the laser emitter 20 of this embodiment. The laser emitter 120 shown in FIG. 10 also serves as a guidewire. As shown in FIG. 10, the laser emitter 120 includes a laser emitter 121, an optical transmission line 122, and a guidewire body 124. The laser emitter 121 is held by the guidewire body 124. A recess 124a is formed on the side of the guidewire body 124 shown in FIG. 10. The laser emitter 121 is held by the guidewire body 124 while being housed in the recess 124a of the guidewire body 124. The laser emitter 121 is capable of emitting laser in a direction (the same direction as the radial direction C within the tubular member 2) perpendicular to the longitudinal direction D of the guidewire body 124 (the same direction as the axial direction A within the tubular member 2). The optical transmission line 122 extends along the longitudinal direction D of the guidewire body 124 and is optically connected to the laser emission unit 121. The optical transmission line 122 shown in FIG. 10 may extend in the longitudinal direction D through a hollow portion defined inside the guidewire body 124. However, the optical transmission line 122 may also extend in the longitudinal direction D outside the guidewire body 124 along the guidewire body 124. In this way, by configuring the laser emitter 120 to double as a guidewire, it is possible to emit a laser from the laser emission unit 121 to a target site such as a calcified region X (see FIG. 1, etc.) without removing the guidewire from the living body, thereby improving the efficiency of the procedure.

11 is a diagram showing a catheter set 300 including a laser emitter 220 as another modified example of the laser emitter 20 of this embodiment. The laser emitter 220 shown in FIG. 11 comprises a laser emitter 221, an optical transmission line 222, and a tubular body 225. The laser emitter 221 is held on the side wall of the tubular body 225. More specifically, the laser emitter 221 shown in FIG. 11 is held on the outer surface of the side wall of the tubular body 225. However, the laser emitter 221 may also be embedded in the side wall of the tubular body 225. The laser emitter 221 is capable of emitting laser in a direction (the same direction as the radial direction C within the tubular member 2) perpendicular to the longitudinal direction E of the tubular body 225 (the same direction as the axial direction A within the tubular member 2). The optical transmission line 222 extends along the longitudinal direction E of the tubular body 225 and is optically connected to the laser emitter 221. The optical transmission line 222 shown in FIG. 11 may extend in the longitudinal direction E through a guidewire insertion space 225a defined inside the tubular body 225 and through which a guidewire GW can be inserted. However, the optical transmission line 222 may also extend in the longitudinal direction E outside the tubular body 225 along the tubular body 225. In this way, by providing the laser emitter 220 with the tubular body 225 through which a guidewire GW can be inserted, it is possible to emit a laser from the laser emitter 221 to a target site such as a calcified region X (see FIG. 1, etc.) without removing the guidewire GW from the living body, thereby improving the efficiency of the procedure.

12A and 12B are diagrams showing a catheter set 400 including a laser emitter 320 as yet another modified example of the laser emitter 20 of this embodiment. The catheter set 400 shown in FIGS. 12A and 12B differs from the catheter set 300 shown in FIG. 11 described above only in the configuration of the tubular body 325. The tubular body 325 defines a guidewire insertion space 325a therein through which a guidewire GW can be inserted. As shown in FIG. 12B, a slit 325b is formed in the side wall of the tubular body 325, penetrating from the outer surface to the inner surface and extending from the distal end of the tubular body 325 along the longitudinal direction F (the same direction as the axial direction A within the tubular member 2). The laser emitter 221 shown in FIGS. 12A and 12B is held at the position of the slit 325b in the tubular body 325. The laser emission unit 221 can emit a laser in a direction perpendicular to the longitudinal direction F of the tubular body 325 (the same direction as the radial direction C within the tubular member 2). In this way, the laser emission unit 221 may be held at the position of the slit 325b formed in the side wall of the tubular body 325.

Second Embodiment
13 to 14B, a catheter set 500 as another embodiment of the catheter set according to the present disclosure will be described. The catheter set 500 is identical in configuration to the catheter set 100 of the first embodiment described above, except for the arrangement of the light-transmitting portion 41 and the light-blocking portion 42 of the catheter 401 and the inclusion of a resistance mechanism 450. Here, the above differences will be mainly described, and a description of the same configuration as the catheter set 100 will be omitted.

Figure 13 is a cross-sectional view of the catheter set 500. More specifically, Figure 13 is a cross-sectional view of the catheter set 500 taken along a plane that includes the central axis O of the tubular member 402 and is parallel to the central axis O. Figures 14A and 14B are views showing details of the resistance mechanism 450.

As shown in Figures 13 to 14B, the catheter set 500 includes a catheter 401 and a laser emitter 420.

As shown in Figure 13, the catheter 401 includes a tubular member 402 and an expansion member 3. The expansion member 3 has the same configuration as that of the first embodiment described above. The tubular member 402 defines an internal storage space 2a capable of storing a laser emitter 420.

As shown in FIG. 13, the tubular member 402 of this embodiment has transparent portions 41 and light-shielding portions 42 at the positions covered by the expansion member 3. Furthermore, the transparent portions 41 and light-shielding portions 42 of this embodiment are formed alternately along the axial direction A at the positions covered by the expansion member 3. More specifically, in the covered portion 2c of the tubular member 402 of this embodiment, which is the portion whose periphery in the radial direction C is covered by the expansion member 3, the transparent portions 41 and light-shielding portions 42 are arranged alternately along the axial direction A.

Therefore, when the laser is emitted in the radial direction C from the laser emission unit 21 of the laser emitter 420 while moving the laser emitter 420 in the axial direction A, the laser from the laser emission unit 21 passes through the transparent portion 41 in the radial direction C at the position of the transparent portion 41 of the tubular member 402 in the axial direction A. On the other hand, the laser from the laser emission unit 21 does not or does not easily pass through the light-shielding portion 42 in the radial direction C at the position of the light-shielding portion 42 of the tubular member 402 in the axial direction A. This prevents the laser from being repeatedly irradiated at the same position on the expansion member 3. Repeated irradiation of the laser at the same position on the expansion member 3 may unintentionally reduce the intensity of the laser-induced shock waves output. Furthermore, damage to the expansion member 3 due to repeated irradiation of the laser at the same position on the expansion member 3 can be prevented. As a result, direct irradiation of the laser at the blood vessel BV due to damage to the expansion member 3 can be prevented. Furthermore, since there is no need to control the output of the laser emission unit 21 of the laser emitter 420 itself, the above effects can be achieved with a simple configuration.

。 More specifically, in this embodiment, the transparent portions 41 are arranged intermittently in the axial direction A. The transparent portions 41 are annular transparent windows that are endless in the circumferential direction B. The light-shielding portions 42 are arranged between the multiple transparent portions 41 in the axial direction A. More specifically, the light-shielding portions 42 are also arranged intermittently in the axial direction A at positions covered by the extension member 3. The light-shielding portions 42 are also light-shielding walls that are endless in the circumferential direction B. As long as the transparent portions 41 and the light-shielding portions 42 are arranged alternately along the axial direction A, the configuration is not limited to multiple transparent portions 41 arranged intermittently in the axial direction A. The transparent portions 41 may be formed, for example, by a single spiral transparent window extending spirally. However, it is preferable that the transparent portions 41 are arranged intermittently in the axial direction A, as in this embodiment. This makes it possible to suppress variation in the output of the laser-induced shock wave in the circumferential direction B. If the output of the laser-induced shock waves varies in the circumferential direction B, it may be difficult to align the catheter 401 with the calcified region X in the circumferential direction B, for example, due to the relationship with the position of the calcified region X (see Figure 1, etc.) in the circumferential direction B within the blood vessel BV. In response to this, by configuring multiple transparent portions 41 to be intermittently arranged in the axial direction A, it is possible to suppress the variation in the output of the laser-induced shock waves in the circumferential direction B, improving the operability of the catheter 401.

Next, the resistance mechanism 450 of this embodiment will be described with reference to Figures 14A and 14B. The tubular member 402 and laser emitter 420 of this embodiment are equipped with a resistance mechanism 450. The resistance mechanism 450 is a mechanism that makes the resistance force when the laser emitter 420 moves distally in the axial direction A relative to the tubular member 402 greater than the resistance force when the laser emitter 420 moves proximal to the axial direction A relative to the tubular member 402.

The presence of this resistance mechanism 450 makes it possible to prevent the laser emitter 420 from moving back and forth in the axial direction A. As mentioned above, if the same position on the extension member 3 is repeatedly irradiated with a laser, the intensity of the output laser-induced shock wave may unintentionally decrease. Therefore, the provision of the resistance mechanism 450 makes it possible to prevent the same position on the extension member 3 from being repeatedly irradiated with a laser.

Specifically, the tubular member 402 of this embodiment includes an inner tube 11 and an outer tube 12. The inner tube 11 of the tubular member 402 of this embodiment protrudes further in the proximal direction A2 than the hub 4 (see Figure 1, etc.). As shown in Figures 14A and 14B, the tubular member 402 of this embodiment also includes an outer tube 451 fixed to the proximal end portion 11a of the inner tube 11. The outer tube 451 includes an outer tube main body 451a and a distal wall portion 451b that closes the distal end of the outer tube main body 451a. The proximal end portion 11a of the inner tube 11 is fitted into and fixed to an opening 451b1 defined in the distal wall portion 451b. The proximal end of the outer tube main body 451a is an open end.

The laser emitter 420 of this embodiment is movable in the axial direction A within the storage space 2a of the tubular member 402. The laser emitter 420 of this embodiment includes a laser emitter 21, an optical transmission line 22, and a drive shaft 23. As shown in Figures 14A and 14B, the laser emitter 420 of this embodiment also includes a torque transmission connector 426 fixed to the proximal side of the drive shaft 23, and a connector 427 fixed to the proximal end 23a of the drive shaft 23 and connectable to a drive device (not shown) that is connected to an optical source. When the connector 427 is connected to the drive device, the optical transmission line 22 is optically connected to the drive device. When the connector 427 is connected to the drive device, the drive device is able to drive the drive shaft 23 in the circumferential direction B via the torque transmission connector 426.

As shown in Figures 14A and 14B, the connector portion 427 of this embodiment includes a connector main body 427a that can be connected to a drive device, and an inner cylindrical portion 427b that protrudes from the connector main body 427a in the distal direction A1. The proximal end portion 23a of the drive shaft 23 is fitted into and fixed to the inner cylindrical portion 427b of the connector portion 427.

As shown in Figures 14A and 14B, the inner tube portion 427b of the connector portion 427 is inserted into the outer tube main body 451a. The inner tube portion 427b of this embodiment comprises an inner tube main body 427b1 and an annular flange portion 427b2 that protrudes outward in the radial direction C from the inner tube main body 427b1. The flange portion 427b2 is elastically deformable so that its outer tip in the radial direction C swings in the axial direction A relative to its base end fixed to the inner tube main body 427b1. The outer tip of the flange portion 427b2 in the radial direction C abuts against the inner surface of the inner tube portion 427b of the connector portion 427. The flange portion 427b2 of this embodiment is configured to easily swing from the proximal side to the distal side in the axial direction A, thereby elastically deforming. Therefore, the laser emitter 420 of this embodiment can easily move from the position shown in FIG. 14A to the position shown in FIG. 14B by elastically deforming the flange portion 427b2 so that it swings distally in the axial direction A. In contrast, the laser emitter 420 of this embodiment cannot easily move from the position shown in FIG. 14B to the position shown in FIG. 14A because the flange portion 427b2 is less likely to elastically deform so that it swings proximally in the axial direction A. Therefore, while the laser emitter 420 is pulled back in the proximal direction A2 relative to the catheter 401, after laser irradiation is performed on a target site such as the calcified region X (see FIG. 1, etc.), the laser emitter 420 can be prevented from being returned again in the distal direction A1. This prevents the laser emitter 420 from irradiating the same position on the expansion member 3 with laser light from the laser emitter 21 of the laser emitter 420.

In this way, the tubular member 402 and laser emitter 420 of this embodiment, thanks to the outer tube 451 and connector portion 427, achieve a resistance force greater when the laser emitter 420 moves distally in the axial direction A relative to the tubular member 402 than when the laser emitter 420 moves proximally in the axial direction A relative to the tubular member 402. In other words, the resistance mechanism 450 of this embodiment is composed of the outer tube 451 of the tubular member 402 and the connector portion 427 of the laser emitter 420.

15A and 15B are diagrams showing a modified example of the resistance mechanism 450 shown in FIGS. 14A and 14B. The resistance mechanism 450 shown in FIGS. 15A and 15B differs only in that it has a protrusion 451a1 on the inner surface of the outer tube main body 451a of the outer tube body 451 of the tubular member 402. The protrusions 451a1 may be, for example, multiple and intermittently arranged in the circumferential direction B. The protrusions 451a1 may also be, for example, an annular convex portion that has no end in the circumferential direction B. As shown in FIGS. 15A and 15B, the distal surface of the protrusion 451a1 is formed by a sliding slope 452 that slopes toward the central axis O as it moves in the proximal direction A2. In contrast, the proximal surface of the protrusion 451a1 is formed by an abutment surface 453 that is perpendicular to the axial direction A. 15A and 15B, the flange portion 427b2 elastically deforms to swing toward the distal side in the axial direction A, and the flange portion 427b2 slides on the sliding inclined surface 452 of the protrusion 451a1 to climb over the protrusion 451a1, thereby easily moving from the position shown in FIG. 15A to the position shown in FIG. 15B. In contrast, the laser emitter 420 shown in FIGS. 15A and 15B does not easily move from the position shown in FIG. 15B to the position shown in FIG. 15A because the flange portion 427b2 does not elastically deform to swing toward the proximal side in the axial direction A, and the flange portion 427b2 abuts against the abutment surface 453 of the protrusion 451a1. As such, the resistance mechanism 450 shown in FIGS. 15A and 15B can more effectively prevent the laser emitter 420 from moving back in the distal direction A1, compared to the configuration shown in FIGS. 14A and 14B.

The resistance mechanism 450 is not limited to the configuration shown in Figures 14A to 15B. The resistance mechanism 450 may have any other configuration as long as it is a mechanism that makes the resistance force when the laser emitter 420 moves distally in the axial direction A relative to the tubular member 402 greater than the resistance force when the laser emitter 420 moves proximal to the axial direction A relative to the tubular member 402.

The catheter set 500 of this embodiment has a configuration in which the transparent portions 41 and the light-blocking portions 42 are alternately arranged along the axial direction A at positions covered by the expansion member 3. The catheter set 500 of this embodiment also has a resistance mechanism 450. However, the catheter set 500 does not have to have both of these two configurations. In other words, the catheter set 500 may have only one of these two configurations.

[Third embodiment]
Next, a catheter set 600 as another embodiment of the catheter set according to the present disclosure will be described with reference to Figures 16 to 20. Figure 16 is a diagram showing a cross section perpendicular to the axial direction A of the optical transmission line 522 of the laser emitter 520 of the catheter set 600. Figures 17 to 20 are diagrams showing an example of a procedure using the catheter set 600 to successively perform fragmentation of a calcified region X (see Figure 1) as treatment of a target site and diagnosis of the target site after treatment.

The catheter set 600 of this embodiment differs from the catheter set 100 of the first embodiment described above in that the optical transmission line 522 that transmits light to the laser emission unit 21 of the laser emitter 520 has a structure that allows it to transmit lasers of different power outputs; more specifically, the optical transmission line 522 is a double-clad fiber; the rest of the configuration is the same. Therefore, only the above differences will be described here.

As shown in Figure 16, the double-clad fiber serving as the optical transmission line 522 comprises a core 522a, an inner clad 522b that covers the radial outside of the core 522a, and an outer clad 522c that covers the radial outside of the inner clad 522b. The refractive index of the core 522a is higher than the refractive index of the inner clad 522b and higher than the refractive index of the outer clad 522c. The refractive index of the inner clad 522b is also higher than the refractive index of the outer clad 522c. Such a double-clad fiber allows a high-power treatment laser LS1 (see Figure 18) to propagate within the inner clad 522b, and allows a diagnostic laser LS2 (see Figure 20) to propagate within the core 522a. In other words, the laser emission unit 21 can be used to emit the treatment laser LS1, and can also be used to send and receive the diagnostic laser LS2 used to obtain diagnostic images of the target area after treatment using OCT (Optical Coherence Tomography) or OFDI (Optical Frequency Domain Imaging).

17 to 20, an example of a procedure using the catheter set 600 to consecutively fragment the calcified region X (see FIG. 1) as a treatment of the target site and diagnose the target site after treatment will be described. FIG. 17 shows a state in which the laser emitter 520 is housed within the catheter 1, prior to treatment of the target site. FIG. 18 shows a state in which treatment of the target site has been completed using the treatment laser LS1 emitted from the laser emitter 21 of the laser emitter 520. More specifically, FIG. 18 shows a state in which, from the state shown in FIG. 17, the laser emitter 520 is moved in the proximal direction A2 of the axial direction A relative to the catheter 1 while being rotated in the circumferential direction B relative to the catheter 1 (see the white arrow in FIG. 17). During this movement, the treatment laser LS1 emitted from the laser emission unit 21 can send laser-induced shock waves over a predetermined range in the extension direction of the blood vessel BV (see Figure 1, etc.) and along the entire circumferential direction of the inner wall of the blood vessel BV. In Figure 18, the treatment laser LS1 emitted from the laser emission unit 21 is shown by a dashed line as the laser emitter 520 moves from the position shown in Figure 17 to the position shown in Figure 18. This makes it possible to perform treatment of the target site by fracturing the calcified region X (see Figure 1) within the blood vessel BV.

Figure 19 is a diagram showing the state in which the laser emitter 520 has been returned from the position shown in Figure 18 to the position shown in Figure 17. More specifically, Figure 19 is a diagram showing the state in which the laser emitter 520 has been moved from the position shown in Figure 18 in the distal direction A1 of the axial direction A relative to the catheter 1 (see the white arrow in Figure 19) and returned to the same position as in Figure 17. During this movement, the treatment laser LS1 (see Figure 18) and the diagnostic laser LS2 (see Figure 20) are not emitted from the laser emission unit 21. Furthermore, during this movement, the laser emitter 520 is moved in the distal direction A1 without rotating in the circumferential direction B relative to the catheter 1.

20 shows the state after the transmission and reception of the diagnostic laser LS2 has been completed in order to obtain a diagnostic image of the target site after treatment, from the state shown in FIG. 19. More specifically, FIG. 20 shows the state after the laser emitter 520 has been moved again in the proximal direction A2 of the axial direction A relative to the catheter 1, while rotating the laser emitter 520 in the circumferential direction B relative to the catheter 1, from the state shown in FIG. 19. During this movement, the diagnostic laser LS2 is transmitted and received by the laser emitter 21. In FIG. 20, the diagnostic laser LS2 transmitted and received as the laser emitter 520 moves from the position shown in FIG. 19 to the position shown in FIG. 20 is shown by dashed lines. This makes it possible to obtain a diagnostic image of the target site after treatment. In other words, with the catheter set 600, it is possible to obtain a diagnostic image of the target site after treatment without removing the catheter 1 and the laser emitter 520 from the living body after treatment of the target site.

In this way, by using a double-clad fiber as the optical transmission line 522 of the laser emitter 520, treatment of the target area and diagnosis of the target area after treatment can be performed continuously.

The catheters and catheter sets according to the present disclosure are not limited to the specific configurations shown in the above-described embodiments and modifications, and various modifications, alterations, and combinations are possible without departing from the scope of the claims. Therefore, other catheters and catheter sets constructed by combining the components of the catheters and catheter sets shown in the above-described embodiments and modifications also fall within the technical scope of the present disclosure.

This disclosure relates to catheters and catheter sets.

1, 401: Catheter 2, 402: Tubular member 2a: Storage space 2b: Flow path 2c: Covering portion 2d: Exposed portion 3: Expansion member 3a: First transmission layer 3b: Second transmission layer 3c: Light absorption layer 4: Hub 4a: Hub connector portion 4b: Hub proximal opening 5: Fluid storage space 6: Guidewire insertion portion 6a: Guidewire insertion hole 6a1: Proximal end portion 6b of guidewire insertion portion: Inner extension portion 11: Inner tube 11a: Proximal end portion 11b of inner tube: Distal end portion of inner tube (an example of a distal end portion of a tubular member)
12: Outer tube 13: Marker member 20, 120, 220, 320, 420, 520: Laser emitter 21, 121, 221: Laser emitter 22, 122, 222, 522: Optical transmission line 23: Drive shaft 23a: Proximal end portion 41 of drive shaft: Transmitting portion 42: Light-shielding portion 100, 200, 300, 400, 500, 600: Catheter set 124: Guide wire body 124a: Recess 225, 325: Tubular body 225a, 325a: Guide wire insertion space 325b: Slit 426: Torque transmission connector 427: Connector portion 427a: Connector body 427b: Inner tube Section 427b1: Inner tube main body 427b2: Flange section 450: Resistance mechanism 451: Outer tube body 451a: Outer tube main body 451a1: Protrusion section 451b: Distal wall section 451b1: Opening 452: Sliding slope 453: Abutment surface 522a: Core 522b: Inner cladding 522c: Outer cladding A: Axial direction A1: Distal direction A2: Proximal direction B: Circumferential direction C: Radial direction D: Longitudinal direction of guidewire main body E, F: Longitudinal direction of tubular body O: Central axis line X of tubular member: Calcified region BV: Blood vessel GW: Guidewire L1: Circumferential irradiation range of the light absorption layer of the expansion member LS1: Treatment laser LS2: Diagnostic laser

Claims (13)

a tubular member defining an accommodation space therein capable of accommodating a laser emitter;
an expansion member that covers the radial outside of the tubular member and is capable of expanding and contracting in the radial direction,
the tubular member is capable of transmitting, in the radial direction, a laser emitted from the laser emitter accommodated in the accommodation space at a position where the tubular member is covered by the expansion member,
The expansion member is
a transmission layer that allows the laser emitted from the laser emitter accommodated in the accommodation space to transmit in the radial direction;
a light-absorbing layer positioned radially outward of the transmission layer and capable of absorbing the laser that has passed through the transmission layer. The tubular member is provided at a position where it is covered by the expansion member.
a transmission portion that allows the laser emitted from the laser emitter accommodated in the accommodation space to transmit in the radial direction;
a light-shielding portion having a lower transmittance of the laser than the light-transmitting portion,
The catheter according to claim 1 , wherein the light-transmitting portions and the light-blocking portions are alternately formed along the axial direction of the tubular member. a plurality of the transmission portions are arranged intermittently in the axial direction,
The catheter according to claim 2 , wherein the light-shielding portion is disposed between the plurality of transmitting portions in the axial direction. A catheter according to any one of claims 1 to 3;
and a catheter set comprising the laser emitter. The laser emitter is
a drive shaft that is movable in the axial direction of the tubular member within the accommodation space of the tubular member;
a laser emitter carried on a distal end of the drive shaft;
an optical transmission line extending inside the drive shaft and optically connected to the laser emission unit;
The catheter set according to claim 4 , wherein the optical transmission line is configured to be capable of transmitting lasers of different power outputs. The laser emitter is
A guidewire body;
a laser emission unit held by the guidewire body;
5. The catheter set according to claim 4, further comprising: an optical transmission line extending along the longitudinal direction of the guidewire body and optically connected to the laser emission unit. The laser emitter is
a tubular body defining a guidewire insertion space therein through which a guidewire can be inserted;
a laser emission unit held on a side wall of the tube;
The catheter set according to claim 4 , further comprising: an optical transmission line extending along the longitudinal direction of the tubular body and optically connected to the laser emission unit. The catheter set described in claim 7, wherein a slit is formed in the side wall of the tubular body, penetrating from the outer surface to the inner surface and extending along the longitudinal direction from the distal end of the tubular body. The catheter set according to claim 4, wherein the catheter includes a guidewire insertion portion defining a guidewire insertion hole therein through which a guidewire can be inserted. the guidewire insertion portion includes an inner extending portion that extends along the axial direction of the tubular member, inside the radial direction of the expansion member,
The catheter set according to claim 9 , wherein the inner extending portion is capable of transmitting, in the radial direction, the laser emitted from the laser emitter housed in the housing space of the tubular member. The catheter set described in claim 9, wherein the guidewire insertion portion is located only distal to the expansion member, and the proximal end of the guidewire insertion portion is fixed to the distal end of the tubular member. The catheter set described in claim 11, wherein the storage space of the tubular member is closed at the distal end. the laser emitter is movable within the accommodation space of the tubular member in an axial direction of the tubular member,
5. The catheter set according to claim 4, wherein the tubular member and the laser emitter are provided with a resistance mechanism that makes a resistance force exerted on the laser emitter when it moves distally in the axial direction relative to the tubular member greater than a resistance force exerted on the laser emitter when it moves proximally in the axial direction relative to the tubular member.