Catheter, treatment assistance device, and treatment method

Abstract

A catheter according to the present disclosure comprises: a tubular body that defines an inner housing space; and an expansion body that covers the outside of the tubular body in the radial direction. The tubular body comprises a first transmissive part in a position where the outside in the radial direction is covered by the expansion body, the first transmissive part allowing emitted light emitted from a light irradiation part housed in the housing space to be transmitted to the outside in the radial direction. The expansion body comprises a second transmissive part through which the emitted light can be transmitted to the outside in the radial direction. At least one transmissive part of the first transmissive part and the second transmissive part comprises a transmission control part in which the transmittance of the emitted light from the inside to the outside in the radial direction varies so as to increase from the proximal side to the distal side of the tubular body in the longitudinal direction or from the distal side to the proximal side of the tubular body in the longitudinal direction.

Description

Catheter, treatment support device, and treatment method

[0001] The present disclosure relates to a catheter, a treatment support device, and a treatment method.

[0002] Patent Document 1 discloses a method for treating an AAA, which is one of aortic aneurysms, by arranging a reinforcing device or a reinforcing composition at at least one arterial site adjacent to an arterial site adjacent to the AAA and increasing the mechanical rigidity of the site. "AAA" is an abbreviation for abdominal aortic aneurysm.

[0003] U.S. Patent Application Publication No. 2016 / 0262914

[0004] As one of the causes of the occurrence and expansion of an aneurysm, a difference in the hardness of adjacent vascular regions of an artery is considered. In a normal blood vessel with uniform hardness, even if the blood vessel expands during the systolic phase of the heart, axial wall stress is unlikely to occur in the blood vessel wall. On the other hand, when a region with non-uniform blood vessel hardness occurs due to arteriosclerosis or the like, the blood vessel wall of the flexible blood vessel region expands more than the blood vessel wall of the adjacent hard blood vessel region. As a result, stress concentrates at the boundary between the flexible blood vessel region and the hard blood vessel region, and wall stress that causes the blood vessel wall to extend axially is likely to occur at the boundary. This axial wall stress at the boundary is considered to induce the occurrence and expansion of an aneurysm. Patent Document 1 discloses that by applying a surgical adhesive from the outside to harden the adjacent region of the AAA (the region adjacent to the aortic aneurysm) in a mouse model of AAA, the difference in hardness between the AAA region and the adjacent region of the AAA is reduced, and the expansion of the aneurysm is significantly reduced.

[0005] Similar to the above method, for a small aneurysm, it is conceivable to arrange a bare stent in the normal blood vessel part adjacent to the small aneurysm as the diseased blood vessel part and suppress the influence of the difference in blood vessel hardness at the boundary between the diseased blood vessel part and the normal blood vessel part. For example, Patent Document 1 also discloses that by arranging a bare stent in the region adjacent to the aortic aneurysm to reinforce it, the expansion of the aneurysm can be suppressed.

[0006] However, when using implants such as bare stents, there are risks such as thrombus formation by the implant, dispersal of the formed thrombus, infection through the implant, and deterioration of the implant. Also, if the aneurysm expands after the procedure, the implant can become an obstacle when additional treatment such as conventional EVAR or artificial blood vessel replacement is performed. "EVAR" is an abbreviation for endovascular aneurysm repair. Furthermore, while uniformly reinforcing the normal blood vessel adjacent to the lesioned vessel may mitigate the difference in stiffness between the lesioned and normal vessels, a difference in vascular stiffness will occur between the reinforced normal vessel and the unreinforced normal vessel adjacent on the opposite side of the lesioned vessel, making it easier for stress to concentrate at these boundaries. This may prevent the aneurysm from expanding.

[0007] The purpose of this disclosure is to provide a catheter, a treatment support device, and a treatment method that facilitate the reinforcement of the portion of a normal blood vessel adjacent to a diseased blood vessel, such that it becomes harder as it approaches the diseased blood vessel, without the use of implants.

[0008] A catheter according to a first aspect of the present disclosure comprises: (1) an elongated tubular body that internally partitions a housing space containing or capable of housing a light irradiation unit; and an expandable body that covers the radially outer side of the tubular body and is capable of expanding and contracting in the radial direction, wherein the tubular body has a first transmissive portion at a position covered on its radially outer side by the expandable body, which is capable of transmitting emitted light emitted from the light irradiation unit in the housing space to the radially outer side, and the expandable body has a second transmissive portion that is capable of transmitting the emitted light that has passed through the first transmissive portion of the tubular body to the radially outer side, and at least one of the first transmissive portion and the second transmissive portion has a transmissive adjustment portion that changes the transmittance of the emitted light from the radially inner to the radially outer side such that it increases from the proximal to the distal side in the longitudinal direction of the tubular body, or from the distal to the proximal side in the longitudinal direction.

[0009] A catheter as one embodiment of the present disclosure is the catheter according to (1) above, comprising (2) a drug that is activated by the light emitted from the light irradiation section, wherein the drug is supported on the radially outer surface of the second permeable portion of the expander, or can be contained in the radially inner internal space of the expander, and can be discharged from the radially inner to the second permeable portion through a discharge hole formed in the second permeable portion of the expander.

[0010] A catheter as one embodiment of the present disclosure is the catheter according to (1) or (2) above, wherein the light irradiation unit is capable of simultaneously emitting the emitted light radially outward over the entire circumferential area of ​​the tubular body in the housing space, and the longitudinal length from which the light irradiation unit can emit the emitted light is the same as or longer than the longitudinal length of the transmission adjustment unit.

[0011] A catheter as one embodiment of the present disclosure is the catheter according to any one of (1) to (3) above, comprising (4) a shaft body that can be inserted into the housing space of the tubular body, the shaft body comprising the light irradiation portion.

[0012] A catheter as one embodiment of the present disclosure is the catheter according to (4) above, further comprising (5) a probe shaft body that can be inserted into the housing space of the tubular body, wherein the probe shaft body comprises an ultrasonic element.

[0013] One embodiment of the present disclosure is a catheter as described in (4) above, wherein the shaft further comprises an ultrasonic element near the light irradiation portion.

[0014] A treatment support device as a second aspect of the present disclosure is a treatment support device comprising: (7) a catheter as described in (5) or (6) above; and a processing device comprising: a control unit that calculates the vascular stiffness corresponding to each of the multiple positions based on ultrasound received by the ultrasound element at the multiple positions in the longitudinal direction, and outputs the calculated vascular stiffness linked to each of the multiple positions.

[0015] A third aspect of the present disclosure is a treatment method comprising: (8) a treatment method performed using the catheter described in (2) above, the method comprising: a catheter delivery step of delivering the expander to the boundary between a diseased blood vessel and a normal blood vessel; a drug delivery step of expanding the expander to deliver the drug to the portion of the normal blood vessel adjacent to the diseased blood vessel; and a light irradiation step of emitting the emitted light from the light irradiation section located in the housing space of the tubular body through the transmission adjustment section provided in at least one of the first and second transmission sections, radially outward from the second transmission section, to irradiate the portion of the normal blood vessel adjacent to the diseased blood vessel to which the drug has been delivered.

[0016] According to this disclosure, it is possible to provide a catheter, a treatment support device, and a treatment method that make it easier to reinforce the portion of a normal blood vessel adjacent to a diseased blood vessel, such that it becomes harder as it approaches the diseased blood vessel, without using implants.

[0017] Figure 1 shows a catheter as one embodiment of the present disclosure. Figure 2 shows an example of a treatment method performed using the catheter shown in Figure 1. Figure 3 shows an overview of the pre-treatment diagnostic step. Figure 4 shows an overview of the catheter delivery step. Figure 5 shows an overview of the drug delivery step. Figure 6 shows an overview of the light irradiation step. Figure 7 shows an overview of the post-treatment diagnostic step. Figure 8 shows a modified example of the shaft body shown in Figure 1. Figure 9 shows an example of the configuration of the transmission adjustment section. Figure 1 shows an example of the configuration of the transmission adjustment section. Figure 9 shows an example of the configuration of the transmission adjustment section. Figure 1 shows the length relationship between the transmission adjustment section and the light irradiation section. Figure 1 shows a modified example of the catheter body shown in Figure 1.

[0018] Hereinafter, embodiments of the catheter, treatment support device, and treatment method relating to this disclosure will be illustrated with reference to the drawings. In each figure, identical components are denoted by the same reference numerals.

[0019] Figure 1 shows a catheter 100 as one embodiment of the catheter according to the present disclosure.

[0020] The catheter 100 is inserted percutaneously into a blood vessel and used in treatment to alleviate differences in the stiffness of the blood vessel walls in adjacent blood vessel regions without the use of implants. Differences in the stiffness of the blood vessel walls in adjacent blood vessel regions are considered to be one of the causes of aneurysm development and enlargement. Therefore, the catheter 100 may be used, for example, in treatment to suppress the development and enlargement of aneurysms. The aneurysms that can be treated with the catheter 100 are not particularly limited, but examples include abdominal aortic aneurysms and thoracic aortic aneurysms. In the following embodiment, an example in which the catheter 100 is used for the treatment of an abdominal aortic aneurysm as the diseased blood vessel is described, but the diseased blood vessel treated with the catheter of this disclosure is not limited to aneurysms such as abdominal aortic aneurysms.

[0021] As shown in Figure 1, the catheter 100 of this embodiment comprises a catheter body 1, a shaft body 50, and a probe shaft body 60. The shaft body 50 is equipped with a light irradiation section 51. The probe shaft body 60 is equipped with an ultrasonic element 61. In Figure 1, for the sake of explanation, the catheter body 1 is shown in a cross-sectional view, and the shaft body 50 and the probe shaft body 60 are shown in side views.

[0022] The catheter body 1 of this embodiment comprises a long tubular body 2, an expander 3, and a drug 4.

[0023] The tubular body 2 of this embodiment has an internally partitioned housing space 2a capable of accommodating a light irradiation unit 51 and an ultrasonic element 61. Specifically, the shaft body 50 and the probe shaft body 60 of this embodiment are inserted into the housing space 2a of the tubular body 2 of the catheter body 1 for use. As will be described in detail later, the light irradiation unit 51 of the shaft body 50 of this embodiment can emit light used for treatment within the housing space 2a of the tubular body 2. Also, as will be described in detail later, the ultrasonic element 61 of the probe shaft body 60 of this embodiment can transmit and receive ultrasound used for vascular diagnosis within the housing space 2a of the tubular body 2.

[0024] Hereinafter, in the catheter 100, the longitudinal direction of the tubular body 2 will be referred to as "longitudinal direction A". Furthermore, within longitudinal direction A of the catheter 100, the direction from the tip side of the tubular body 2 inserted into the body to the proximal end side, which is manipulated outside the body by an operator such as a physician, will be referred to as "proximal A1" of longitudinal direction A, and the opposite direction will be referred to as "distal" of longitudinal direction A. In addition, in the catheter 100, the direction around the axis with the tubular body 2 as the central axis will be referred to as "circumferential direction B". Furthermore, in the catheter 100, the radial direction of a virtual circle with the tubular body 2 as the central axis in a cross section perpendicular to longitudinal direction A will be referred to as "radial direction C".

[0025] The expandable body 3 covers the outside of the tubular body 2 in the radial direction C and is capable of expanding and contracting in the radial direction C.

[0026] The tubular body 2 is provided with a first transmissive portion 21 at a position where its outer surface in the radial direction C is covered by the expandable body 3, which allows the emitted light emitted from the light irradiation section 51 in the containment space 2a to pass through to the outer surface in the radial direction C. The expandable body 3 is also provided with a second transmissive portion 31 which allows the emitted light that passes through the first transmissive portion 21 of the tubular body 2 to pass through to the outer surface in the radial direction C.

[0027] Here, at least one of the first and second transmission sections 21 and 31 is equipped with a transmission adjustment section 70 that changes the transmittance of the emitted light from the light irradiation section 51 from the inside to the outside in the radial direction C, increasing from the proximal side A1 to the distal side A2 in the longitudinal direction A, or from the distal side A2 to the proximal side A1 in the longitudinal direction A. More specifically, in this embodiment, the second transmission section 31 is equipped with a transmission adjustment section 70 that changes the transmittance of the emitted light from the light irradiation section 51 from the inside to the outside in the radial direction C, increasing from the distal side A2 to the proximal side A1 in the longitudinal direction A. Therefore, in the housing space 2a of the tubular body 2, the amount of transmitted light per unit time that passes through the transmission adjustment section 70 of the second transmission section 31 of the expander 3 from the inside to the outside in the radial direction C, and is emitted to the outside of the expander 3 (hereinafter simply referred to as "amount of light transmitted through the transmission adjustment section 70 of the light emission section 51") is greater on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A.

[0028] The drug 4 in this embodiment is a vascular strengthening agent that is activated by light emitted from the light irradiation unit 51. More specifically, the drug 4 in this embodiment is absorbed by the blood vessel wall and activated by light emitted from the light irradiation unit 51, thereby promoting the binding of collagen and elastin in the blood vessel wall. This makes it possible to strengthen the strength of the blood vessel wall (increase the stiffness of the blood vessels). Examples of such drugs 4 include dimerized naphthalimide or a pharmaceutically acceptable salt thereof, for example, dimerized naphthalimide or a pharmaceutically acceptable salt thereof, for example, chemical name 2,2'-((ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))bis(6-((2-(2-(2-aminoethoxy)ethoxy)ethyl)amino)-1H-benzo[de]isoquinoline-1,3(2H)-dione),6-[2-[2-(2-aminoethoxy)ethoxy]ethylamino]-2-[2-[2-[2-[6-[2-[2-(2-aminoethoxy)ethoxy]ethylamino]-1,3-dioxobenzo[de]isoquinoline-2-yl] Examples include drugs described as toxy]ethoxy]ethyl]benzo[de]isoquinoline-1,3-dione, 2,2'-[1,2-ethanediylbis(oxy-2,1-ethanediyl)]bis[6-({2-[2-(2-aminoethoxy)ethoxy]ethyl}amino)-1H-benzo[de]isoquinoline-1,3(2H)-dione], or 1H-benzo[de]isoquinoline-1,3(2H)-dione, 2,2'-[1,2-ethanediylbis(oxy-2,1-ethanediyl)]bis[6-[[2-[2-(2-aminoethoxy)ethoxy]ethyl]amino]-(9Cl), or identified by CAS registration number 438200-66-9. The dimerized naphthalimide, which is the drug in this embodiment, is activated by irradiation with light of a wavelength of 450 nm from the light irradiation unit 51. By absorbing the dimerized naphthalimide into the blood vessel wall and irradiating it with light emitted from the light irradiation unit 51 to activate it, the amino acids that make up collagen and elastin in the blood vessel wall are oxidized, and reactive intermediates are formed. Crosslinking occurs when the reactive intermediates form covalent bonds with each other. This can reinforce the strength of the blood vessel wall. However, the drug 4 only needs to be photoreactive and capable of promoting the crosslinking of collagen or elastin.Specifically, examples include drugs such as riboflavin-5'-sodium phosphate, rose bengal, palladium bacteriochlorin 13'-(2-sulfoethyl)amide dipotassium salt, palladium bacteriopheoferbide, bifunctional diazopyruvoyl, and Pterin, or combinations thereof. When a drug other than dimeric naphthalimide is used as drug 4, the light irradiation unit 51 may be configured to irradiate with light of a predetermined wavelength that activates drug 4. Specifically, it is preferable to configure the system to allow irradiation with light at a wavelength of around 375 nm or around 450 nm when using riboflavin-5'-sodium phosphate, light at a wavelength of around 555 nm when using rose bengal, light at a wavelength of around 750 nm when using palladium bacteriochlorin 13'-(2-sulfoethyl)amide dipotassium salt, light at a wavelength of around 320-390 nm when using bifunctional diazopyruvoyl, and light at a wavelength of around 320-400 nm when using Pterin. Furthermore, the drug used as drug 4 may be, for example, methylene blue, methylene green, riboflavin, proflavin, fluorescein, eosin, or 4-amino-1,8-naphthalimide. In addition, the drug may appropriately contain additives such as pH adjusters or osmotic pressure adjusters. In this application, photoreactivity refers to the property of absorbing light and becoming activated (excited), thereby triggering chemical reactions such as the generation of reactive oxygen species and radicals, oxidation-reduction reactions, polymerization reactions, bond cleavage and formation, and changes in molecular structure.

[0029] As shown in Figure 1, the drug 4 in this embodiment is supported on the outer surface 31a of the second permeable portion 31 of the expanded body 3, which is the outer surface in the radial direction C. More specifically, the drug 4 in this embodiment is supported on the outer surface 31a of the second permeable portion 31 such that it covers at least the outer surface of the permeation adjustment portion 70.

[0030] Therefore, in the containment space 2a of the tubular body 2, the transmitted light emitted from the light irradiation unit 51 that passes through the transmission adjustment unit 70 of the second transmission unit 31 of the expandable body 3 from the inside to the outside in the radial direction C is irradiated onto the drug 4. As described above, the amount of light emitted from the light irradiation unit 51 that passes through the transmission adjustment unit 70 is greater on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A. Therefore, in the portion of the drug 4 that covers the transmission adjustment unit 70, the activity state of the drug 4 can be increased on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A. In other words, the degree of reinforcement of the blood vessel wall strength by the drug 4 can be increased on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A, at a position radially C outside the transmission adjustment unit 70.

[0031] As described above, the presence of the transmission adjustment section 70 makes it easier for the amount of light emitted from the light irradiation section 51 to pass through the transmission adjustment section 70 to gradually increase from the distal side A2 to the proximal side A1 in the longitudinal direction A. Therefore, as described above, the degree of reinforcement of the blood vessel wall strength by the drug 4 also tends to gradually increase from the distal side A2 to the proximal side A1 in the longitudinal direction A. In other words, with the catheter 100, the presence of the transmission adjustment section 70 makes it easier to reinforce the portion of the normal blood vessel adjacent to the abdominal aortic aneurysm, which is the diseased blood vessel, so that it becomes harder as it approaches the diseased blood vessel, without using an implant. That is, it makes it easier to reinforce the vascular stiffness of the portion of the normal blood vessel adjacent to the abdominal aortic aneurysm, which is the diseased blood vessel, so that it approaches the vascular stiffness of the diseased blood vessel as it approaches the diseased blood vessel.

[0032] First, an overview of the treatment method performed using the catheter 100 of this embodiment will be described. Figure 2 is a flowchart showing an example of a treatment method performed using the catheter 100 of this embodiment.

[0033] The treatment method shown in Figure 2 includes a pre-treatment diagnostic step S1, a catheter delivery step S2, a drug delivery step S3, a light irradiation step S4, and a post-treatment diagnostic step S5. Figure 3 is a diagram illustrating the overview of the pre-treatment diagnostic step S1. Figure 4 is a diagram illustrating the overview of the catheter delivery step S2. Figure 5 is a diagram illustrating the overview of the drug delivery step S3. Figure 6 is a diagram illustrating the overview of the light irradiation step S4. Figure 7 is a diagram illustrating the overview of the post-treatment diagnostic step S5. Figures 3 to 7 illustrate the overview of steps S1 to S5 in a treatment in which a catheter 100 is used to reinforce the portion X2a (hereinafter referred to as "proximal adjacent portion X2a") that is proximal to the abdominal aortic aneurysm, which is the diseased vessel portion X1, within the normal vessel portion X2.

[0034] As shown in Figure 3, in the pre-treatment diagnostic step S1, first, an IVUS catheter 500, separate from the catheter 100, is percutaneously inserted into the blood vessel and delivered to a location near the boundary X3 between the lesional blood vessel X1 and the normal blood vessel X2. "IVUS" is an abbreviation for intravascular ultrasound. Next, ultrasound information is acquired near the boundary X3 using the IVUS catheter 500. Specifically, the probe 501 of the IVUS catheter 500, which includes an ultrasonic element 501a, acquires ultrasound information at multiple locations in the direction of extension of the blood vessel near the boundary X3. Next, the vascular stiffness corresponding to each of these multiple locations is calculated based on the ultrasound information acquired at each of these multiple locations. The method for calculating vascular stiffness based on the ultrasound information acquired at each of the multiple locations may be, for example, the same as the method performed by the treatment support device 200 including the probe shaft body 60 in the drug delivery step S3 described later. By performing this pre-procedure diagnostic step S1, the location and condition of the proximal adjacent portion X2a to be reinforced can be identified. This allows for the selection of an appropriate catheter 100 in which the amount of drug 4 released into the body is set according to the position in the longitudinal direction A, corresponding to the location and condition of the proximal adjacent portion X2a identified in the pre-procedure diagnostic step S1. The IVUS catheter 500 used in the pre-procedure diagnostic step S1 is removed from the body after the completion of the pre-procedure diagnostic step S1.

[0035] As shown in Figure 4, in the catheter delivery step S2, the catheter body 1 is first inserted percutaneously into the blood vessel, and the expander 3 is delivered to a position near the boundary X3 between the diseased blood vessel portion X1 and the normal blood vessel portion X2. Specifically, the expander 3 shown in Figure 4 is delivered to a position near the boundary X3 between the abdominal aortic aneurysm, which is the diseased blood vessel portion X1, and the proximal adjacent portion X2a of the normal blood vessel portion X2. More specifically, the expander 3 shown in Figure 4 is positioned in the aorta so as to extend longitudinally A across the boundary X3, from a position distal to the boundary X3 to a position proximal to the boundary X3. As shown in Figure 4, the expander 3 is in a deflated state during the catheter delivery step S2.

[0036] As shown in Figure 4, in the catheter delivery step S2, the probe shaft 60 is then inserted into the housing space 2a of the tubular body 2, which is already inserted into the blood vessel. At this time, the probe shaft 60 is inserted into the housing space 2a of the tubular body 2 so that it reaches a position where the ultrasonic element 61 is covered by the expandable body 3. As shown in Figure 4, the probe shaft 60 has a connector portion 62 at the proximal end A1 in the longitudinal direction A that can be connected to the processing device 80. By connecting the connector portion 62 to the processing device 80, the ultrasonic element 61 is electrically connected to the processing device 80.

[0037] In Figures 3 and 4, for the sake of explanation, the vessel walls of the diseased vessel portion X1 and the normal vessel portion X2, which have different hardnesses, are shown with different hatching, with boundary X3 as the boundary. The hardness of the vessel wall of the diseased vessel portion X1 is harder than the hardness of the vessel wall of the normal vessel portion X2.

[0038] As shown in Figure 5, in the drug delivery step S3, the expandable body 3 is expanded to deliver the drug 4 to the central adjacent portion X2a of the normal blood vessel portion X2. As shown in Figure 1, the tubular body 2 comprises a containment space 2a, as well as a flow path 2b through which a fluid such as liquid can move to expand and contract the expandable body 3 in the radial direction C. Specifically, the expandable body 3 in this embodiment comprises an annular internal space 3a between itself and the tubular body 2 in the radial direction C. The expandable body 3 can expand outward in the radial direction C by the delivery of fluid to the internal space 3a through the flow path 2b. Conversely, the expandable body 3 can contract inward in the radial direction C by the discharge of fluid from the internal space 3a through the flow path 2b.

[0039] As described above, the drug 4 in this embodiment is supported on the outer surface 31a of the second permeable portion 31 of the expander 3. Therefore, when the expander 3 expands radially outward in the drug delivery step S3, the drug 4 supported on the outer surface 31a of the expander 3 can be brought into contact with the inner wall of the central adjacent portion X2a of the normal blood vessel portion X2. In this way, the drug 4 can be delivered to the central adjacent portion X2a of the normal blood vessel portion X2.

[0040] The drug delivery step S3 may be performed while observing the condition near the vascular boundary X3 using the ultrasonic element 61 of the probe shaft body 60, which is housed in the housing space 2a of the tubular body 2. In this way, the position in which the expander 3 is expanded can be adjusted while reconfirming the position and condition of the proximal adjacent portion X2a identified in the pre-treatment diagnosis step S1. Furthermore, over-expansion of the expander 3 can be suppressed.

[0041] The ultrasonic element 61 is capable of transmitting ultrasonic waves outward in the radial direction C within the housing space 2a of the tubular body 2, and is also capable of receiving ultrasonic waves that are reflected back. The processing device 80 includes a control unit 81. The control unit 81 calculates the vascular stiffness corresponding to each of the multiple locations in the longitudinal direction A based on the ultrasonic waves received by the ultrasonic element 61 at these locations, and can output the calculated vascular stiffness linked to each of the multiple locations. Specifically, the control unit 81 can calculate the stiffness of the vascular wall as the vascular stiffness of the lesional vascular portion X1 and the normal vascular portion X2 near the boundary X3, based on the change in vascular diameter, vascular wall thickness, etc., calculated from the ultrasonic waves received by the ultrasonic element 61. The control unit 81 also calculates this vascular stiffness at each of the multiple locations in the longitudinal direction A. The control unit 81 can then output the calculated vascular stiffness at each location linked to the location information of each location. This makes it possible to diagnose the stiffness state of the vascular wall in the vascular region near the boundary X3. The control unit 81 may, for example, display the vascular stiffness linked to the position information on a display unit such as a liquid crystal monitor. The process, including the calculation of vascular stiffness at each position, is performed by a treatment support device 200, which includes a catheter 100 and a processing device 80, as shown in Figure 5.

[0042] The control unit 81 may be a general-purpose processor such as a CPU or GPU, or a dedicated processor specialized for a specific process. "CPU" is an abbreviation for central processing unit. "GPU" is an abbreviation for graphics processing unit.

[0043] The vascular stiffness corresponding to each of the multiple locations mentioned above can be calculated, for example, from the change in the diameter of the blood vessels associated with the heartbeat. When the diameter of the blood vessels during cardiac systole is Ds, the diameter of the blood vessels during cardiac diastole is Dd, and the vascular stiffness of the blood vessels is ε, then ε = (Ds - Dd) / Dd × 100%. Ds, the diameter of the blood vessels during cardiac systole, refers to the diameter of the blood vessels during cardiac systole, especially at the end of systole, and is synonymous with the maximum blood vessel diameter when the blood vessels are most dilated. Similarly, Dd, the diameter of the blood vessels during cardiac diastole, refers to the diameter of the blood vessels during cardiac diastole, especially at the end of diastole, and is synonymous with the minimum blood vessel diameter when the blood vessels are most constricted. In other words, the vascular stiffness of the blood vessels may also be calculated from the change in the diameter of the blood vessels associated with the pulse. In this way, when calculating the vascular stiffness of the blood vessels from the change in the diameter of the blood vessels associated with the heartbeat or pulse, the reception of ultrasound by the ultrasound element 61 is performed while moving in the longitudinal direction A in accordance with the heartbeat or pulse. At this time, it is necessary to know the diameter of the blood vessels during cardiac systole and diastole. Therefore, the ultrasonic element 61 is kept stationary at each of the multiple positions in the longitudinal direction A without moving for at least one heartbeat or one pulse. For example, if the above-mentioned multiple positions are set at 5 mm intervals in the longitudinal direction A, the ultrasonic element 61 is kept stationary at one position and receives ultrasound for one heartbeat or one pulse. Subsequently, the ultrasonic element 61 is moved 5 mm in the longitudinal direction A and kept stationary at another adjacent position, receiving ultrasound for one heartbeat or one pulse. By repeating this process, the stiffness of the blood vessel walls of the diseased blood vessel portion X1 and the normal blood vessel portion X2 can be calculated over a predetermined length of the blood vessel near the boundary X3.

[0044] As a modification example, instead of matching the heartbeat or pulse, a moving operation may be performed so that the position of the ultrasonic element 61 in the longitudinal direction A changes at a timing when both the maximum diameter and the minimum diameter of the blood vessel can be calculated. For example, the change in the diameter of the blood vessel is observed with the ultrasonic element 61, and after identifying both the blood vessel contraction start point where the increasing blood vessel diameter turns to decrease and the blood vessel dilation start point where the decreasing blood vessel diameter turns to increase, a moving operation such as moving the ultrasonic element 61 by 5 mm and repeating the observation is performed. When the control unit 81 automatically performs the moving operation, the control unit 81 controls the movement of the probe shaft body 60 in the longitudinal direction A in the accommodation space 2a of the tubular body 2, and for each position of a plurality of positions, until both the blood vessel contraction start point and the blood vessel dilation start point are identified, ultrasonic information is acquired. The control unit 81 continuously calculates the diameter of the blood vessel from the acquired ultrasonic information, and at a timing when both the blood vessel contraction start point and the blood vessel dilation start point can be identified at least once, controls the movement of the probe shaft body 60 in the longitudinal direction A in the accommodation space 2a to move the ultrasonic element 61 to the next position in the longitudinal direction A. The diameter of the blood vessel at the blood vessel contraction start point is the maximum blood vessel diameter when the blood vessel is most dilated in the central side adjacent portion X2a as the adjacent region of the aortic aneurysm which is the treatment site, and corresponds to Ds which is the diameter of the blood vessel in the systolic phase of the heart. The diameter of the blood vessel at the blood vessel dilation start point is the minimum blood vessel diameter when the blood vessel is most contracted in the central side adjacent portion X2a as the adjacent region of the aortic aneurysm which is the treatment site, and corresponds to Dd which is the diameter of the blood vessel in the diastolic phase of the heart. That is, the control unit 81 continuously calculates the diameter of the blood vessel from the acquired ultrasonic information for each position of a plurality of positions, and identifies both the blood vessel contraction start point where the maximum diameter of the blood vessel turns from increase to decrease and the blood vessel dilation start point where the minimum diameter of the blood vessel turns from decrease to increase at that position. The control unit 81 may control the movement of the probe shaft body 60 in the longitudinal direction A in the accommodation space 2a at a timing when both the blood vessel contraction start point and the blood vessel dilation start point at each position of a plurality of positions can be identified at least once, and move the ultrasonic element 61 to the next position in the longitudinal direction A.

[0045] As shown in FIG. 6, in the light irradiation step S4, the emitted light emitted from the light irradiation unit 51 located in the accommodation space 2a of the tubular body 2 is emitted to the outside in the radial direction C from the second transmission unit 31 of the expansion body 3 through the transmission adjustment unit 70, and irradiates the central adjacent part X2a to which the drug 4 has been delivered.

[0046] Specifically, in the light irradiation step S4, after removing the probe shaft body 60 used in the drug delivery step S3 from the accommodation space 2a of the tubular body 2, the shaft body 50 is inserted into the accommodation space 2a of the tubular body 2. At this time, the shaft body 50 is inserted into the accommodation space 2a of the tubular body 2 so that the light irradiation unit 51 reaches a position covered by the expansion body 3. As shown in FIG. 6, the shaft body 50 includes a connector portion 52 connectable to the light source device 90 at the end portion on the proximal side A1 in the longitudinal direction A. By connecting the connector portion 52 to the light source device 90, the light irradiation unit 51 becomes in a state capable of emitting emitted light.

[0047] The emitted light emitted from the light irradiation unit 51 passes through the first transmission unit 21 of the tubular body 2 and the transmission adjustment unit 70 of the second transmission unit 31 of the expansion body 3, and irradiates the drug 4 delivered to the central adjacent part X2a. As described above, the transmission amount of the emitted light from the light irradiation unit 51 through the transmission adjustment unit 70 is larger on the proximal side A1 in the longitudinal direction A than on the distal side A2 in the longitudinal direction A. Therefore, the reinforcement intensity of the central adjacent part X2a by the drug 4 can be reduced from the side closer to the abdominal aortic aneurysm as the diseased blood vessel part X1 toward the side moving away. Thereby, the blood vessel wall of the central adjacent part X2a can be reinforced so as to become harder as it approaches the abdominal aortic aneurysm as the diseased blood vessel part X1. As a result, the expansion of the abdominal aortic aneurysm as the diseased blood vessel part X1 can be suppressed.

[0048] In FIG. 6, for convenience of explanation, the blood vessel wall of the central adjacent part X2a reinforced to become harder as it approaches the abdominal aortic aneurysm as the diseased blood vessel part X1 by the light irradiation step S4 is shown by a different hatching from the blood vessel wall of the diseased blood vessel part X1 and the blood vessel wall of the normal blood vessel part X2 other than the central adjacent part X2a.

[0049] As shown in Figure 7, in the post-treatment diagnosis step S5, the stiffness of the vascular wall near the boundary X3 after the light irradiation step S4 is diagnosed in the same manner as in the drug delivery step S3. Specifically, the shaft body 50 used in the light irradiation step S4 is removed from the housing space 2a of the tubular body 2, the probe shaft body 60 is inserted into the housing space 2a, and the stiffness of the vascular wall near the boundary X3 is diagnosed. This makes it possible to confirm that the stiffness of the vascular wall of the proximal adjacent portion X2a, which was reinforced by the light irradiation step S4, is getting stiffer as it approaches the lesional vascular portion X1, that is, that the treatment to suppress the expansion of the abdominal aortic aneurysm as the lesional vascular portion X1 has been completed. If the treatment is judged to be insufficient in the post-treatment diagnosis step S5, for example, only the light irradiation step S4 described above, or both the drug delivery step S3 and the light irradiation step S4 described above, may be performed again.

[0050] If, in the post-procedure diagnostic step S5, it is determined that treatment to suppress the expansion of the abdominal aortic aneurysm in the lesional vascular portion X1 has been completed, the procedure can be completed by removing the catheter body 1 and probe shaft body 60 from the body.

[0051] In this embodiment, the pre-treatment diagnostic step S1 is performed using an IVUS catheter 500 separate from the catheter 100, but is not limited to this. The pre-treatment diagnostic step S1 may also be performed, for example, using the probe shaft 60 of the catheter 100.

[0052] In this embodiment, the probe shaft 60 is inserted into the containment space 2a in both the drug delivery step S3 and the post-treatment diagnosis step S5, and the vascular stiffness near the boundary X3 is observed using the probe shaft 60, but the embodiment is not limited to this. In either or both of the drug delivery step S3 and the post-treatment diagnosis step S5, for example, an IVUS catheter 500 (see Figure 3), separate from the catheter 100, may be inserted into the containment space 2a, and the vascular stiffness near the boundary X3 may be observed using the IVUS catheter 500. The processing device 80 may be configured to connect to both the probe shaft 60 of the catheter 100 and the IVUS catheter 500, as in this embodiment.

[0053] In this embodiment, the transmission adjustment unit 70 is configured such that the transmittance of the emitted light from the light irradiation unit 51 from the inside to the outside in the radial direction C increases from the distal side A2 to the proximal side A1 in the longitudinal direction A, but the configuration is not limited to this. The transmission adjustment unit 70 may be configured such that the transmittance of the emitted light from the light irradiation unit 51 from the inside to the outside in the radial direction C increases from the proximal side A1 to the distal side A2 in the longitudinal direction A. In such a case, the catheter body 1 of the catheter 100 is inserted into the aorta such that the proximal side A1 is the central side and the distal side A2 is the peripheral side, and the central adjacent portion X2a (see Figure 3, etc.) is reinforced. Also, in Figures 3 to 7, the central adjacent portion X2a adjacent to the central side of the abdominal aortic aneurysm, which is the lesional vascular portion X1, is reinforced, but in some cases the peripheral adjacent portion X2b adjacent to the distal side of the abdominal aortic aneurysm may be reinforced. In such cases, as in Figures 3 to 7, the catheter body 1 of the catheter 100 is inserted into the aorta such that the proximal A1 is the distal end and the distal A2 is the proximal end, and the distal adjacent portion X2b is reinforced. Thus, the transmission adjustment unit 70 may be configured such that the transmittance of the emitted light from the light irradiation unit 51 from the inside to the outside in the radial direction C increases from the proximal A1 to the distal A2 in the longitudinal direction A.

[0054] In the catheter 100 of this embodiment, the second permeable portion 31 of the expandable body 3 is equipped with a transmission adjustment portion 70, but the configuration is not limited to this. The transmission adjustment portion 70 is provided so that the amount of light emitted from the second permeable portion 31 toward the outside in the radial direction C is greater on the proximal side A1 than on the distal side A2 in the longitudinal direction A, or greater on the distal side A2 than on the proximal side A1 in the longitudinal direction A. For this reason, the first permeable portion 21 of the tubular body 2 may also be equipped with a transmission adjustment portion 70. In other words, the catheter 100 may be configured such that only one of the first permeable portion 21 of the tubular body 2 and the second permeable portion 31 of the expandable body 3 is equipped with a transmission adjustment portion 70. Furthermore, the catheter 100 may be configured such that the first permeable portion 21 of the tubular body 2 and the second permeable portion 31 of the expandable body 3 each are equipped with a transmission adjustment portion 70.

[0055] In the catheter 100 of this embodiment, the drug 4 is supported on the radially C outer surface 31a of the second permeable portion 31 of the expandable body 3, but the configuration is not limited to this. The drug may, for example, be contained in the inner internal space 3a of the expandable body 3 in the radially C direction, and may be released from the inside to the outside of the second permeable portion 31 through a discharge hole formed in the second permeable portion 31 of the expandable body 3. In such a case, the drug is a liquid, and the catheter 100 may not contain the drug. In other words, the catheter 100 itself does not contain the drug, and the catheter 100 only needs to be configured to be able to fill the internal space 3a of the expandable body 3 with a liquid drug. Details of such a configuration will be described later (see Figure 11).

[0056] Furthermore, the catheter 100 of this embodiment includes a shaft body 50 that can be inserted into the housing space 2a of the tubular body 2 and includes a light irradiation unit 51, in addition to the catheter body 1 which includes the tubular body 2 and the expandable body 3. However, the catheter 100 is not limited to this configuration. The catheter 100 may also have a configuration without the shaft body 50. In such a case, the tubular body 2 may have a configuration in which the light irradiation unit 51 is always housed in the housing space 2a. In other words, the tubular body 2 may have a light irradiation unit 51 that is always housed in the housing space 2a. However, it is preferable that the catheter 100 includes a shaft body 50 that can be inserted into the tubular body 2, in addition to the catheter body 1. By doing so, when calculating vascular stiffness in the drug delivery step S3 (see Figure 5) and the post-treatment diagnosis step S5 (see Figure 7) described above, the light irradiation unit 51 can be removed from the housing space 2a. Therefore, the probe shaft body 60 can be easily inserted into the housing space 2a for the execution of the drug delivery step S3 and the post-treatment diagnosis step S5. Furthermore, by removing the light irradiation unit 51 from the housing space 2a during the execution of the drug delivery step S3 and the post-treatment diagnosis step S5, it is possible to prevent the light irradiation unit 51 from becoming an obstacle to the transmission and reception of ultrasound by the ultrasonic element 61 during the drug delivery step S3 and the post-treatment diagnosis step S5.

[0057] Furthermore, the catheter 100 of this embodiment includes a probe shaft body 60 that is inserted into the housing space 2a of the tubular body 2 and is equipped with an ultrasonic element 61, in addition to the catheter body 1 which includes the tubular body 2 and the expandable body 3, but the catheter is not limited to this configuration. The catheter 100 may also be configured without the probe shaft body 60. However, for the purpose of performing at least one of the drug delivery step S3 (see Figure 5) and the post-procedure diagnosis step S5 (see Figure 7) described above, it is preferable that the catheter 100 includes a probe shaft body 60 in addition to the catheter body 1.

[0058] Furthermore, the catheter 100 of this embodiment comprises both a shaft body 50 equipped with a light irradiation unit 51 and a probe shaft body 60 equipped with an ultrasonic element 61, but is not limited to this configuration. As shown in Figure 8, the shaft body 50 may further include an ultrasonic element 61 near the light irradiation unit 51 in addition to the light irradiation unit 51. The shaft body 50 shown in Figure 8 further includes an ultrasonic element 61 on the distal side A2 in the longitudinal direction A relative to the light irradiation unit 51, but is not limited to this configuration. The shaft body 50 may further include an ultrasonic element 61 on the proximal side A1 in the longitudinal direction A relative to the light irradiation unit 51.

[0059] The treatment method described above (see Figures 2 to 7) performed using the catheter 100 of this embodiment is a treatment method to suppress the expansion of an already formed abdominal aortic aneurysm, but is not limited to this treatment method. The catheter 100 may also be used, for example, in treatment to suppress the development of an abdominal aortic aneurysm before it is formed.

[0060] Furthermore, in the treatment method described above (see Figures 2 to 7), in the drug delivery step S3 (see Figure 5) and the post-treatment diagnosis step S5 (see Figure 7), the ultrasonic element 61 transmits and receives ultrasound through the first transparent portion 21 of the tubular body 2 and the second transparent portion 31 of the expanded body 3. Therefore, the first transparent portion 21 and the second transparent portion 31 in this embodiment are made of a material that is ultrasonically transparent. However, the ultrasonic element 61 may transmit and receive ultrasound at, for example, a position on the proximal side A1 or distal side A2 in the longitudinal direction A with respect to the expanded body 3. In this case, the portion of the tubular body 2 through which the ultrasound transmitted and received by the ultrasonic element 61 passes only needs to be made of a material that is ultrasonically transparent.

[0061] In the treatment method described above (see Figures 2 to 7), the probe shaft 60 is housed in the housing space 2a of the tubular body 2 during the drug delivery step S3 (see Figure 5), but the method is not limited to this. The drug delivery step S3 may be performed without using the probe shaft 60. However, it is preferable to use the probe shaft 60 in the drug delivery step S3 so that the position for expanding the expander 3 can be accurately positioned. Furthermore, as described above, by performing the drug delivery step S3 while observing with the ultrasonic element 61 of the probe shaft 60 housed in the housing space 2a of the tubular body 2, over-expansion of the expander 3 can be suppressed.

[0062] The tubular body 2 internally partitions a containment space 2a so as to include the central axis O. Furthermore, the tubular body 2 in this embodiment partitions a flow path 2b extending along the longitudinal direction A within the peripheral wall that partitions the containment space 2a.

[0063] More specifically, the tubular body 2 of this embodiment comprises a long tubular body 22 and a hub 23 attached to the proximal side A1 of the tubular body 22 in the longitudinal direction A. The containment space 2a of this embodiment is formed across the tubular body 22 and the hub 23 so as to penetrate both the tubular body 22 and the hub 23 in the longitudinal direction A. In other words, the containment space 2a of this embodiment extends from a proximal opening 2a1 formed at the proximal end of the hub 23, which is the proximal end of the tubular body 2, to a distal opening 2a2 formed at the distal end of the tubular body 22, which is the distal end of the tubular body 2. A valve body 24 capable of suppressing leakage of fluids such as blood may be placed in the proximal opening 2a1. Furthermore, a check valve may be placed in the distal opening 2a2, for example, to allow liquid to flow out of the containment space 2a to the outside and to restrict the inflow of liquid from the outside into the containment space 2a.

[0064] If a check valve is not provided, in the light irradiation step S4, it is preferable to perform light irradiation while injecting a liquid that does not obstruct light irradiation, such as physiological saline, from a port in the hub 23 that communicates with the containment space 2a, in order to restrict the inflow of blood from the distal opening 2a2 into the containment space 2a. In addition, an acoustic medium such as physiological saline may be injected into the containment space 2a to remove air bubbles and other contaminants present in the containment space 2a and to facilitate ultrasonic transmission and reception by the ultrasonic element 61 of the probe shaft body 60. This acoustic medium is injected from a port in the hub 23 that communicates with the containment space 2a and discharged into the blood vessel from the distal opening 2a2. Furthermore, the containment space 2a may also function as a guidewire lumen through which a guidewire is inserted via the distal opening 2a2.

[0065] In this embodiment, the shaft body 50 and the probe shaft body 60 are insertable and removable into the housing space 2a through the proximal opening 2a1. In this embodiment, the shaft body 50 and the probe shaft body 60 are insertable and removable into a single housing space 2a, but the configuration is not limited to this. The housing space 2a may extend parallel along the longitudinal direction A and be separated into two lumens, each capable of separately housing the shaft body 50 and the probe shaft body 60. In this case, it is preferable that the lumen capable of housing the probe shaft body 60 has an open tip so that the acoustic medium injected from the port provided in the hub 23 can be discharged. It is also preferable that the lumen capable of housing the shaft body 50 has a closed tip so that blood does not flow in and obstruct the light irradiation.

[0066] In this embodiment, the flow path 2b extends from a proximal opening 2b1 formed in a fluid supply / discharge port 23a provided on the hub 23 and to which a fluid supply / discharge device such as a syringe can be connected, to a distal opening 2b2 that opens into the internal space 3a of the expandable body 3. The expansion and contraction of the expandable body 3 can be performed through the flow path 2b using a fluid supply / discharge device such as a syringe.

[0067] In this embodiment, the first permeable portion 21 of the tubular body 2 is the entire portion of the tubular body 2 that is covered radially C on its outer side by the expandable body 3. However, the first permeable portion 21 may be only a part of the portion of the tubular body 2 that is covered radially C on its outer side by the expandable body 3.

[0068] The first permeable portion 21 of the tubular body 2 may be made of a transparent or translucent resin that can transmit light emitted from the light irradiation portion 51, for example. Examples of materials for the first permeable portion 21 include: polyethylene, polypropylene, polyolefins such as ethylene-propylene copolymer; ethylene-vinyl acetate copolymer (EVA); polyvinyl chloride; polyvinylidene chloride; polystyrene; polyamide; polyimide; polyamide-imide; polycarbonate; poly-(4-methylpentene-1); ionomer; acrylic resin; polymethyl methacrylate; acrylonitrile-butadiene-styrene copolymer (ABS resin); acrylonitrile-styrene copolymer (AS resin); butadiene-styrene copolymer; polyethylene terephthalate. Examples of resin materials include polyesters such as PET, polybutylene terephthalate (PBT), and polycyclohexane terephthalate (PCT); polyethers; polyether ketones (PEK); polyether ether ketones (PEEK); polyetherimides; polyacetals (POM); polyphenylene oxide; modified polyphenylene oxide; polysulfone; polyethersulfone; polyphenylene sulfide; polyarylate; aromatic polyesters (liquid crystal polymers); polytetrafluoroethylene, polyvinylidene fluoride, and other fluorinated resins. Blends containing one or more of these materials are also acceptable.

[0069] Furthermore, as described above, the first permeable portion 21 of the tubular body 2 in this embodiment has ultrasonic permeability. The first permeable portion 21 having ultrasonic permeability can also be realized by using the constituent materials described above. However, it is preferable that the first permeable portion 21 has flexibility, and in this respect, it is particularly preferable that the constituent material of the first permeable portion 21 is polyethylene.

[0070] The expansion body 3 may be attached to the distal end A2 of the tubular body 2 in the longitudinal direction A.

[0071] The expander 3 may be, for example, a non-compliance balloon having an expander body 33 whose maximum outer diameter in the expanded state is predetermined. This maximum outer diameter may be, for example, in the range of 20 to 30 mm. Alternatively, the expander 3 may be a semi-compliance balloon or a compliance balloon in which the maximum outer diameter can be varied. By making the expander 3 a semi-compliance balloon or a compliance balloon, the range of vascular diameters that the expander 3 can accommodate can be broadened.

[0072] The expandable body 3 of this embodiment comprises an expandable main body portion 33, a proximal joint portion 34 connected to the proximal side A1 in the longitudinal direction A of the expandable main body portion 33 and joined to the tubular body 2, and a distal joint portion 35 connected to the distal side A2 in the longitudinal direction A of the expandable main body portion 33 and joined to the tubular body 2. Figure 1 shows the expanded state of the expandable body 3. As shown in Figure 1, the expanded main body portion 33 in the expanded state divides an internal space 3a between itself and the tubular body 2 on the inside in the radial direction C. Furthermore, as shown in Figure 1, the expanded main body 33 in the expanded state comprises a cylindrical portion 33a having the maximum outer diameter, a proximal reduced diameter portion 33b connected to the proximal side A1 in the longitudinal direction A of the cylindrical portion 33a, with the outer diameter decreasing towards the proximal side A1, and a distal reduced diameter portion 33c connected to the distal side A2 in the longitudinal direction A of the cylindrical portion 33a, with the outer diameter decreasing towards the distal side A2.

[0073] In this embodiment, the second permeable portion 31 of the expandable body 3 is the entire expandable main body 33. That is, the second permeable portion 31 extends over the entire longitudinal direction A and the entire circumferential direction B of the expandable main body 33. However, the second permeable portion 31 may be only a part of the expandable main body 33, such as only the cylindrical portion 33a.

[0074] In this embodiment, the transmission adjustment section 70 of the second transmission section 31 is a part of the cylindrical section 33a of the extended main body section 33. More specifically, the transmission adjustment section 70 of this embodiment is a part of the cylindrical section 33a in the longitudinal direction A and extends over the entire circumferential direction B of the cylindrical section 33a. The transmittance of the light emitted from the light irradiation section 51 in the portion of the second transmission section 31 other than the transmission adjustment section 70 is not particularly limited as long as the light emitted from the light irradiation section 51 can be transmitted. In other words, the transmittance of the light emitted from the light irradiation section 51 in the portion of the second transmission section 31 adjacent to the transmission adjustment section 70 in the proximal A1 and distal A2 directions of the longitudinal direction A is not particularly limited as long as the light emitted from the light irradiation section 51 can be transmitted. Therefore, the transmittance of the light emitted from the light irradiation section 51 in the portion of the second transmission section 31 other than the transmission adjustment section 70 may be approximately equal to or less than the transmittance of the portion of the transmission adjustment section 70 in which the transmittance of the light emitted from the light irradiation section 51 is smallest. Furthermore, the transmittance of the light emitted from the light irradiation unit 51 in the portion of the second transmissive unit 31 other than the transmissive adjustment unit 70 may be approximately equal to, or greater than, the transmittance of the portion of the transmissive adjustment unit 70 in which the transmittance of the light emitted from the light irradiation unit 51 is greatest. For example, in the immediate vicinity of the boundary X3 of the proximal adjacent portion X2a, the vascular stiffness may be harder than the vascular wall of the normal vascular portion X2 but softer than the lesioned vascular portion X1. In this case, the transmittance of the light emitted from the light irradiation unit 51 in the portion of the second transmissive unit 31 adjacent to the proximal A1 of the transmissive adjustment unit 70 may be reduced from the distal A2 in the longitudinal direction A to the proximal A1 in the longitudinal direction A. In other words, the transmittance of the emitted light from the light irradiation unit 51 from the inside to the outside in the radial direction C may be configured such that, in the transmission adjustment unit 70, it increases from the distal side A2 to the proximal side A1 in the longitudinal direction A, and in the portion of the transmission adjustment unit 70 adjacent to the proximal side A1, it increases from the proximal side A1 to the distal side A2 in the longitudinal direction A. This makes it possible to more reliably reinforce the vascular stiffness of the portion of the normal blood vessel adjacent to the abdominal aortic aneurysm, which is the diseased blood vessel, so that it approaches the vascular stiffness of the diseased blood vessel as it approaches the diseased blood vessel.

[0075] As described above, the light transmission adjustment section 70 in this embodiment is a part of the cylindrical portion 33a of the extended main body 33, but the configuration is not limited to this. The light transmission adjustment section 70 may be, for example, the entire cylindrical portion 33a.

[0076] The second transparent portion 31 of the extended body 3 may be composed of, for example, a transparent or translucent resin film that can transmit light emitted from the light irradiation portion 51. Examples of materials that make up the resin film include polyethylene terephthalate, polyurethane, polyamide, and silicone rubber. The resin film may also be a laminate formed by stacking multiple layers made of these materials.

[0077] The transmission adjustment portion 70 of the second transmission portion 31 of the extended body 3 may be formed, for example, by applying a frosting treatment to the surface of the resin film of the second transmission portion 31 as described above. The frosting treatment may be performed, for example, by changing the surface roughness of the resin film 71 of the second transmission portion 31 depending on the position in the longitudinal direction A, as shown in Figure 9A. In this way, the degree of diffusion of diffused transmitted light can be made to differ depending on the position in the longitudinal direction A. In Figure 9A, the surface roughness of the region 73a at the most distal A2 is the greatest, and the surface roughness decreases in the order of region 73b, region 73c, and region 73d. In other words, the degree of diffusion of diffused transmitted light decreases as you move towards the proximal side A1 in the longitudinal direction A. Alternatively, the transmission adjustment portion 70 of the second transmission portion 31 of the extended body 3 may be formed, for example, by incorporating a black powder or the like that reduces the transmittance of the light emitted from the light irradiation portion 51 into the constituent material of the resin film of the second transmission portion 31 as described above, with different concentrations along the longitudinal direction A. Furthermore, as shown in Figure 9B, the transmission adjustment section 70 of the second transmission section 31 of the expanded body 3 may be formed, for example, by separately laminating a plurality of layers 72a to 72d with different transmittances of the light emitted from the light irradiation section 51, on a transparent or translucent resin film 71 that can transmit light emitted from the light irradiation section 51, without laminating them in the radial direction C. Also, as shown in Figure 9C, the transmission adjustment section 70 of the second transmission section 31 of the expanded body 3 may be formed, for example, by laminating a plurality of layers 72a to 72d with different transmittances of the light emitted from the light irradiation section 51, on a transparent or translucent resin film 71 that can transmit light emitted from the light irradiation section 51, with the lamination relationship in the radial direction C differing depending on the position in the longitudinal direction A. In Figures 9B and 9C, four layers are shown as the plurality of layers 72a to 72d, but it is not limited to four layers; for example, there may be three or fewer layers, or five or more layers.

[0078] In the catheter 100 of this embodiment, the second permeable portion 31 of the expandable body 3 is equipped with a permeability adjustment portion 70, but as described above, the first permeable portion 21 of the tubular body 2 may also be equipped with a permeability adjustment portion. If the first permeable portion 21 of the tubular body 2 is equipped with a permeability adjustment portion, the permeability adjustment portion may be formed in the same manner as the permeability adjustment portion 70 of the expandable body 3 described above.

[0079] Furthermore, the second permeable portion 31 of the expandable body 3 of this embodiment, including the permeability adjustment portion 70, has ultrasonic permeability as described above. The second permeable portion 31 having ultrasonic permeability can be realized by using the constituent materials of the second permeable portion 31 as described above. When the expandable body 3 is a compliance balloon, it is particularly preferable to use highly elastic silicone rubber or hydrogenated styrene-based thermoplastic elastomer as the constituent material of the second permeable portion 31.

[0080] The light irradiation unit 51 only needs to be capable of emitting light, such as laser light, outward in the radial direction C within the housing space 2a of the tubular body 2. Therefore, the light irradiation unit 51 may be configured to emit light outward in the radial direction C only in a portion of the circumferential direction B. In such a case, by rotating the light irradiation unit 51 in the circumferential direction B, the emitted light that would normally be emitted outward in the radial direction C from the light irradiation unit 51 can be emitted over the entire circumferential direction B. Alternatively, by moving the light irradiation unit 51 in the longitudinal direction A while rotating it in the circumferential direction B, the emitted light from the light irradiation unit 51 can be emitted over the entire circumferential direction B over a predetermined range in the longitudinal direction A. The movement of the light irradiation unit 51 in the longitudinal direction A may be intermittent, such as stopping the light irradiation unit 51 for a certain period of time at each of multiple positions in the longitudinal direction A. In other words, in the light irradiation step S4 described above (see Figure 6), the light irradiation unit 51 is moved to each of the multiple positions in the longitudinal direction A, and light irradiation is performed at each position for a predetermined time. In this way, sufficient light irradiation time can be secured at each of the multiple positions in the longitudinal direction A, and light irradiation can be performed over a wide area in the longitudinal direction A. The light irradiation time by the light irradiation unit 51 at each of the multiple positions in the longitudinal direction A can be set appropriately depending on the intensity of the light emitted from the light irradiation unit 51, but it may be set in the range of several tens to several hundred seconds, such as 60 seconds.

[0081] It is preferable that the light irradiation unit 51 is capable of simultaneously emitting light outwards in the radial direction C across the entire circumferential direction B within the housing space 2a of the tubular body 2. In this way, light emitted from the light irradiation unit 51 can be emitted outwards in the radial direction C across the entire circumferential direction B without rotating the light irradiation unit 51 in the circumferential direction B. Furthermore, as shown in Figure 10, it is preferable that the length L1 in the longitudinal direction A from which such a full-circumferential irradiation type light irradiation unit 51 can emit light outwards in the radial direction C is the same as or longer than the length L2 in the longitudinal direction A of the transmission adjustment unit 70. In other words, it is preferable that the light irradiation unit 51 is a cylindrical type capable of emitting light outwards in the radial direction C across the entire circumferential direction B and over a predetermined range in the longitudinal direction A within the housing space 2a of the tubular body 2. By using such a cylindrical type light irradiation unit 51, the light emitted from the light irradiation unit 51 can be emitted over the entire area in the circumferential direction B, over a predetermined range in the longitudinal direction A, and outward in the radial direction C, without rotating the light irradiation unit 51 in the circumferential direction B or moving it in the longitudinal direction A. Furthermore, it is preferable that L1 ≥ L2 as described above. In this way, the light emitted from the light irradiation unit 51 can be simultaneously irradiated over the entire area in the longitudinal direction A and the entire area in the circumferential direction B of the transmission adjustment unit 70. Therefore, the time required for the light irradiation step S4 (see Figure 6) described above can be shortened.

[0082] The shaft body 50 of this embodiment comprises a light irradiation section 51, a connector section 52, and a long shaft body 53 connecting the light irradiation section 51 and the connector section 52. The shaft body 53 may be equipped with an optical fiber as an optical transmission material capable of transmitting light from a light source device 90 connected to the connector section 52 to the light irradiation section 51.

[0083] The probe shaft body 60 comprises an ultrasonic element 61, a connector portion 62, a long probe shaft body 63 connecting the ultrasonic element 61 and the connector portion 62, and an electrical signal line 64 extending within the probe shaft body 63.

[0084] The ultrasonic element 61 includes an ultrasonic transducer. The ultrasonic transducer can transmit ultrasonic waves based on pulse signals within blood vessels and receive ultrasonic waves reflected from surrounding biological tissue within blood vessels. The ultrasonic transducer may include, for example, a main body and electrodes. The main body may include a piezoelectric element. The piezoelectric element includes, for example, a piezoelectric material such as ceramics or quartz. The ultrasonic element 61 can transmit and receive ultrasonic waves using the ultrasonic transducer.

[0085] As described above, the connector portion 62 can be connected to the processing device 80 (see Figure 4). By connecting the connector portion 62 to the processing device 80, the ultrasonic element 61 is electrically connected to the processing device 80 via the electrical signal line 64.

[0086] The probe shaft body 63 may be a coil shaft composed of, for example, multiple coils with different winding directions around the axis. Examples of materials for the coils include stainless steel and Ni-Ti (nickel-titanium) alloy.

[0087] Furthermore, the processing unit 80 connected to the connector portion 52 of the probe shaft body 60 includes a first drive unit 82 capable of moving the probe shaft body 60 in the longitudinal direction A. The processing unit 80 also includes a second drive unit 83 capable of rotating the probe shaft body 60 in the circumferential direction B. The operation of the first drive unit 82 and the second drive unit 83 may be controlled by the control unit 81. In the pre-treatment diagnostic step S1 described above (see Figure 3), the probe 501 including the ultrasonic element 501a of the IVUS catheter 500 is moved longitudinally within the cylindrical sheath 502 of the IVUS catheter 500 by the first drive unit 82 of the processing unit 80, and rotated circumferentially by the second drive unit 83. Furthermore, in the drug delivery step S3 (see Figure 5) and the post-treatment diagnosis step S5 (see Figure 7) described above, the probe shaft 60 is moved longitudinally A in the housing space 2a of the tubular body 2 by the first drive unit 82 of the processing device 80, and rotated circumferentially B by the second drive unit 83. In this way, the stiffness of the blood vessel wall of the diseased blood vessel X1 and the normal blood vessel X2 can be calculated over a predetermined length near the blood vessel boundary X3 (see Figure 3, etc.). The stiffness of the blood vessel wall may also be calculated using an IVUS catheter having a probe with multiple ultrasonic elements 501a arranged circumferentially, and a processing device 80 without the second drive unit 83. In this case, the probe 501 including the multiple ultrasonic elements 501a is moved longitudinally within the cylindrical sheath 502 of the IVUS catheter 500 by the first drive unit 82 of the processing device 80 without rotating circumferentially.

[0088] The catheter, treatment support device, and treatment method relating to this disclosure are not limited to the specific configurations and processes shown in the embodiments and modifications described above, and various changes, modifications, substitutions, and combinations are possible without departing from the scope of the claims.

[0089] The catheter body 1 of the catheter 100 described above is configured to include a drug 4 supported on the outer surface 31a of the second permeable portion 31 of the expander 3, but is not limited to this configuration. Figure 11 shows a catheter body 301 as one modified example of the catheter body 1. The catheter body 301 differs from the catheter body 1 described above (see Figure 1, etc.) in that the configuration of the expander 303 is different and that it does not include a drug 4. Below, these differences will be mainly explained, and the configuration of the catheter body 301 that is common to the catheter body 1 (see Figure 1, etc.) will not be explained.

[0090] As shown in Figure 11, the catheter body 301 comprises a tubular body 2 and an expandable body 303. The tubular body 2 has the same configuration as the catheter body 1 (see Figure 1, etc.) described above.

[0091] The expandable body 303 differs from the expandable body 3 of the catheter body 1 described above (see Figure 1, etc.) in that it has discharge holes 336 formed in the second permeable section 31. More specifically, in the expandable body 303 shown in Figure 11, multiple discharge holes 336 are formed at the position of the permeability adjustment section 70 of the second permeable section 31. The multiple discharge holes 336 are formed at different positions in the longitudinal direction A and at different positions in the circumferential direction B.

[0092] In the catheter body 301 shown in Figure 11, a liquid drug 404 can be contained in the internal space 3a on the radial side C of the expandable body 303. The drug 404 contained in the internal space 3a can be released from the inside to the outside radially C of the second permeable portion 31 through a discharge hole 336 formed in the second permeable portion 31 of the expandable body 303. In other words, in the catheter body 301 shown in Figure 11, the drug 404 can be delivered to the portion of the normal blood vessel X2 adjacent to the lesioned blood vessel X1 (the proximal adjacent portion X2a in the example shown in Figures 3 to 7) by releasing the drug 404 to the outside of the expandable body 303 from the discharge hole 336.

[0093] More specifically, in the catheter body 301 shown in Figure 11, the drug 404 is delivered to the internal space 3a through the channel 2b, thereby expanding the expander 303 from a contracted state to an expanded state. The drug 404 delivered to the internal space 3a is then released to the outside of the expander 303 through the discharge port 336 of the expanded expander 303. In other words, even with the catheter body 301 shown in Figure 11, the drug delivery step S3 (see Figure 5) can be performed to deliver the drug 404 to the portion of the normal blood vessel X2 adjacent to the lesioned blood vessel X1 (the proximal adjacent portion X2a in the example shown in Figures 3 to 7) by expanding the expander 303 using the drug 404. That is, even when using the catheter body 301 shown in Figure 11, the same treatment method as described above using the catheter body 1 (see Figure 1, etc.) (see Figures 2 to 7) can be implemented.

[0094] In the drug delivery step S3, performed using the catheter body 301 shown in Figure 11, the required amount of drug 404 contained in the internal space 3a is released to the outside through the discharge port 336. As the drug 404 is released through the discharge port 336, saline solution is delivered to the internal space 3a of the expander 303 through the flow path 2b. This allows the expander 303 to maintain its expanded state even after the drug 404 contained in the internal space 3a is released through the discharge port 336. Furthermore, by using saline solution as the fluid contained in the internal space 3a, the portion that is irradiated with light when performing the light irradiation step S4 (see Figure 6) (the central adjacent portion X2a in the example shown in Figures 3 to 7) can be cooled.

[0095] As shown in Figure 11, the plurality of emission holes 336 are formed by distributing them substantially evenly throughout the entire longitudinal direction A and the entire circumferential direction B of the transmission adjustment section 70 of the second transmission section 31, but the configuration is not limited to this. The plurality of emission holes 336 may be formed unevenly in the longitudinal direction A, for example, with more holes on the proximal side A1 and distal side A2 of the transmission adjustment section 70 of the second transmission section 31 than on one side. Specifically, the plurality of emission holes 336 may be arranged in greater numbers on one side of the transmission adjustment section 70, the proximal side A1 and distal side A2 of the longitudinal direction A, where the transmittance of the light emitted from the light irradiation section 51 is high, than on the other side of the transmission adjustment section 70 where the transmittance of the light emitted from the light irradiation section 51 is low. In addition, the cross-sectional areas of each of the plurality of emission holes 336 may be substantially equal or different. Thus, the amount of drug 404 released from the expanded body 303 may vary depending on the position in the longitudinal direction A, based on the number and cross-sectional area of ​​the release holes 336.

[0096] This disclosure relates to catheters, treatment support devices, and treatment methods.

[0097] 1, 301: Catheter body 2: Tubular body 2a: Housing space 2a1: Proximal opening 2a2: Distal opening 2b: Flow path 2b1: Proximal opening 2b2: Distal opening 3, 303: Expanded body 3a: Internal space 4, 404: Drug 21: First permeable section 22: Tubular body 23: Hub 23a: Fluid supply / discharge port 24: Valve body 31: Second permeable section 31a: Outer surface of the second permeable section 33: Expanded body section 33a: Cylindrical section 33b: Proximal diameter reduction section 33c: Distal diameter reduction section 34: Proximal joint section 35: Distal joint section 50: Shaft body 51: Light irradiation section 52: Connector section 53: Shaft body 60: Probe shaft body 61: Ultrasonic element 62: Connector section 63: Probe shaft body 64: Electrical signal line 70: Transmission adjustment unit 71: Resin film 72a-72d: Layers laminated on the resin film 73a-73d: Regions with different surface roughness of the resin film 80: Processing device 81: Control unit 82: First drive unit 83: Second drive unit 90: Light source device 100: Catheter 200: Treatment support device 336: Discharge port 500: IVUS catheter 501: Probe 501a: Ultrasonic element 502: Sheath A: Longitudinal direction A1: Proximal side in the longitudinal direction A2: Distal side in the longitudinal direction B: Circumferential direction C: Radial direction L1: Length in the longitudinal direction of the light irradiation unit L2: Length in the longitudinal direction of the transmission adjustment unit O: Central axis of the tubular body X1: Diseased blood vessel X2: Normal blood vessel X2a: Proximal adjacent part (an example of a part of the normal blood vessel adjacent to the diseased blood vessel) X2b: Peripheral adjacent portion (an example of the portion of the normal blood vessel adjacent to the diseased blood vessel) X3: Boundary

Claims

1. A catheter comprising: an elongated tubular body that internally partitions a housing space containing or capable of housing a light irradiation unit; and an expandable body that covers the radially outer side of the tubular body and is capable of expanding and contracting in the radial direction, wherein the tubular body has a first transmissive portion at a position covered radially by the expandable body, which is capable of transmitting emitted light emitted from the light irradiation unit to the radially outer side in the housing space; the expandable body has a second transmissive portion that is capable of transmitting the emitted light that has passed through the first transmissive portion of the tubular body to the radially outer side, and at least one of the transmissive portions of the first transmissive portion and the second transmissive portion is provided with a transmissive adjustment portion such that the transmittance of the emitted light from the radially inner to the outer side increases from the proximal to distal side in the longitudinal direction of the tubular body, or from the distal to proximal side in the longitudinal direction.

2. The catheter according to claim 1, comprising a drug that is activated by the emitted light from the light irradiation section, wherein the drug is supported on the radially outer surface of the second permeable portion of the expander, or can be contained in the radially inner internal space of the expander, and can be discharged from the radially inner to the outer side of the second permeable portion through a discharge hole formed in the second permeable portion of the expander.

3. The catheter according to claim 1 or 2, wherein the light irradiation unit is capable of simultaneously emitting the emitted light radially outward over the entire circumferential region of the tubular body within the containment space, and the longitudinal length from which the light irradiation unit can emit the emitted light is equal to or longer than the longitudinal length of the transmission adjustment unit.

4. The catheter according to claim 1 or 2, comprising a shaft body that can be inserted into the housing space of the tubular body, wherein the shaft body comprises the light irradiation portion.

5. The catheter according to claim 4, further comprising a probe shaft body that can be inserted into the housing space of the tubular body, wherein the probe shaft body comprises an ultrasonic element.

6. The catheter according to claim 4, wherein the shaft body further comprises an ultrasonic element near the light irradiation portion.

7. A treatment support device comprising: a catheter according to claim 5; and a processing device comprising: a control unit that calculates the vascular stiffness corresponding to each of the multiple positions based on ultrasound received by the ultrasonic element at the multiple positions in the longitudinal direction, and outputs the calculated vascular stiffness linked to each of the multiple positions.

8. A treatment method performed using the catheter described in claim 2, comprising: a catheter delivery step of delivering the expander to the boundary between a diseased blood vessel and a normal blood vessel; a drug delivery step of expanding the expander to deliver the drug to the portion of the normal blood vessel adjacent to the diseased blood vessel; and a light irradiation step of emitting the emitted light from the light irradiation section located in the housing space of the tubular body through the transmission adjustment section provided in at least one of the first and second transmission sections, radially outward from the second transmission section, to irradiate the portion of the normal blood vessel adjacent to the diseased blood vessel to which the drug has been delivered.

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