Catheter, treatment assistance device, and treatment method
The catheter with a light-activated drug layer reinforces the normal blood vessel adjacent to an aneurysm, addressing implant risks and stress concentration issues, effectively preventing aneurysm expansion.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-09-24
- Publication Date
- 2026-04-02
AI Technical Summary
Existing treatments for aneurysms, such as using bare stents, risk thrombus formation, implant dispersal, infection, and create new stress points when the aneurysm expands, while uniform reinforcement can lead to stress concentration at new boundaries.
A catheter with an expandable body and a drug layer that reinforces the normal blood vessel adjacent to the diseased vessel, using a drug that hardens with light activation, ensuring gradual reinforcement from the diseased vessel towards the normal vessel.
The catheter method effectively reinforces the normal blood vessel adjacent to the aneurysm without implants, reducing stress concentration and preventing aneurysm expansion by gradually increasing vascular stiffness towards the diseased area.
Smart Images

Figure JP2025033635_02042026_PF_FP_ABST
Abstract
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 the arterial site adjacent to the AAA and increasing the mechanical rigidity of the site. "AAA" is an abbreviation for abdominal aortic aneurysm.
[0003] US Patent Application Publication No. 2016 / 0262914
[0004] As one of the causes of the occurrence and expansion of aneurysms, a difference in the hardness of adjacent vascular regions of the 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 at the boundary is likely to occur. This axial wall stress at the boundary is considered to induce the occurrence and expansion of aneurysms. Patent Document 1 discloses that by applying a surgical adhesive externally to the AAA adjacent region (aortic aneurysm adjacent region) in a mouse model of AAA to harden it, the difference in hardness between the AAA region and the AAA adjacent region is reduced, and the expansion of the aneurysm is significantly reduced.
[0005] Similar to the above-described method, for a small aneurysm, it is conceivable to arrange a bare stent in the normal blood vessel portion adjacent to the small aneurysm as the diseased blood vessel portion and suppress the influence of the difference in blood vessel hardness at the boundary between the diseased blood vessel portion and the normal blood vessel portion. For example, Patent Document 1 also discloses that by arranging a bare stent in the aortic aneurysm adjacent region for reinforcement, aneurysm expansion 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 in a first aspect of the present disclosure comprises: (1) an elongated body; an expandable body covering the radially outer surface of the elongated body and capable of expanding and contracting in the radial direction; and a drug supported on the outer surface which is the radially outer surface of the expandable body, or housed in the radially inner internal space of the expandable body, and capable of being released to the radially outer side of the expandable body through a plurality of release holes formed in the expandable body, wherein the drug is supported on the outer surface of the expandable body, or can be released from the internal space of the expandable body to the radially outer side of the expandable body through the plurality of release holes, such that the amount of drug released from the expandable body toward the living body increases from the proximal to distal side in the longitudinal direction of the elongated body, or from the distal to proximal side in the longitudinal direction.
[0009] A catheter as one embodiment of the present disclosure is (2) the catheter according to (1) above, wherein a drug layer containing the drug is supported on the outer surface of the expandable body, and the content of the drug in the drug layer differs in the longitudinal direction such that the amount of the drug released increases from the proximal to distal side in the longitudinal direction, or from the distal to proximal side in the longitudinal direction.
[0010] A catheter as one embodiment of the present disclosure is (3) a catheter according to (1) above, wherein the internal space of the expandable body is capable of containing a drug solution containing the drug, and at least one of the cross-sectional area of the plurality of discharge holes and the number of the plurality of discharge holes differs in the longitudinal direction such that the amount of drug released increases from the proximal to the distal side in the longitudinal direction, or from the distal to the proximal side in the longitudinal direction.
[0011] A catheter as one embodiment of the present disclosure is (4) the catheter according to (1) above, wherein the internal space of the expandable body includes a plurality of drug solution containing spaces that are not in communication with each other, each of the plurality of drug solution containing spaces is in communication with the radially outside of the expandable body through separate discharge holes formed at different positions in the longitudinal direction of the plurality of discharge holes, and the plurality of drug solution containing spaces can separately contain a plurality of drug solutions with different concentrations of the drug such that the amount of the drug discharged increases from the proximal to the distal side in the longitudinal direction, or from the distal to the proximal side in the longitudinal direction.
[0012] A catheter as one embodiment of the present disclosure is (5) a catheter according to any one of (1) to (4) above, wherein the elongated body is tubular, and comprises a probe shaft body that can be inserted through the tubular body, and the probe shaft body comprises an ultrasonic element.
[0013] A catheter as one embodiment of the present disclosure is (6) a catheter according to any one of (1) to (4) above, wherein the elongated body is a tubular body that internally partitions a housing space that houses or can house a light irradiation unit, the tubular body has a first permeable portion at a position where the radially outer side is covered by the expandable body, which is capable of transmitting the emitted light emitted from the light irradiation unit to the radially outer side in the housing space, the expandable body has a second permeable portion which is capable of transmitting the emitted light that has passed through the first permeable portion of the tubular body to the radially outer side, and the drug is capable of being activated by the emitted light from the light irradiation unit.
[0014] A catheter as one embodiment of the present disclosure is the catheter described in (6) above, comprising (7) a shaft body that can be inserted into the housing space of the tubular body, the shaft body comprising the light irradiation portion.
[0015] A catheter as one embodiment of the present disclosure is the catheter according to (7) above, further comprising (8) a probe shaft body that can be inserted through the tubular body, wherein the probe shaft body comprises an ultrasonic element.
[0016] A catheter as one embodiment of the present disclosure is the catheter according to (7) above, wherein the shaft further comprises an ultrasonic element near the light irradiation portion.
[0017] A treatment support device as a second aspect of the present disclosure is a treatment support device comprising: (10) a catheter as described in (5), (8), or (9) 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.
[0018] A third aspect of the present disclosure is a treatment method, (11) a treatment method performed using a catheter described in any one of (1) to (10) above, comprising: a catheter delivery step of delivering the expander to a boundary between a diseased blood vessel and a normal blood vessel; and a drug delivery step of expanding the expander to deliver the drug to a portion of the normal blood vessel adjacent to the diseased blood vessel.
[0019] 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.
[0020] This figure shows a catheter as one embodiment of the present disclosure. This is a flowchart showing an example of a treatment method performed using the catheter shown in Figure 1. This figure shows an overview of the pre-treatment diagnostic step in Figure 2. This figure shows an overview of the catheter delivery step in Figure 2. This figure shows an overview of the drug delivery step in Figure 2. This figure shows an overview of the light irradiation step in Figure 2. This figure shows an overview of the post-treatment diagnostic step in Figure 2. This figure shows an example of the configuration of the drug layer. This figure shows a modified example of the shaft body shown in Figure 1. This figure shows an example of the length relationship between the second transmission part and the light irradiation part. This figure shows an example of the length relationship between the second transmission part and the light irradiation part. This figure shows a modified example of the catheter body shown in Figure 1. This figure shows an enlarged view of the vicinity of the expander in Figure 12. This figure shows a modified example of the expander shown in Figure 13. This figure shows a modified example of the expander shown in Figure 13.
[0021] 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.
[0022] Figure 1 shows a catheter 100 as one embodiment of the catheter according to the present disclosure.
[0023] 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.
[0024] 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.
[0025] The catheter body 1 comprises a long body 40, an expander 3, and a drug 4. In this embodiment, the long body 40 is a long tubular body 2.
[0026] The tubular body 2, which serves as the elongated body 40 in this embodiment, has an internally partitioned housing space 2a capable of accommodating the light irradiation unit 51 and the 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.
[0027] Hereinafter, in the catheter 100, the longitudinal direction of the elongated body 40 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 elongated body 40 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 elongated body 40 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 elongated body 40 as the central axis in a cross section perpendicular to longitudinal direction A will be referred to as "radial direction C".
[0028] The expandable body 3 covers the outer surface of the elongated body 40 in the radial direction C and is capable of expanding and contracting in the radial direction C.
[0029] As described above, the elongated body 40 in this embodiment is an elongated tubular body 2. The tubular body 2, as the elongated body 40 in this embodiment, 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.
[0030] 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 strengthens the blood vessel wall. 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, 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 have a configuration that allows 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.
[0031] As shown in Figure 1, the drug 4 in this embodiment is supported on the outer surface 31a, which is the outer surface in the radial direction C of the second permeable portion 31 of the expanded body 3.
[0032] Specifically, in this embodiment, the drug 4 is supported on the outer surface 31a of the second permeable portion 31 of the expander 3 such that the amount released from the expander 3 toward the living body (hereinafter referred to as "amount of drug 4 released into the body") increases from the distal side A2 to the proximal side A1 in the longitudinal direction A. More specifically, in this embodiment, a drug layer 5 containing the drug 4 is supported on the outer surface 31a of the second permeable portion 31 of the expander 3. The drug 4 content in the drug layer 5 differs in the longitudinal direction A such that the amount of drug 4 released into the body increases from the distal side A2 to the proximal side A1 in the longitudinal direction A. In other words, the drug 4 content in the drug layer 5 is greater in the proximal side A1 of the longitudinal direction A than in the distal side A2 of the longitudinal direction A. Therefore, the amount of drug 4 released into the body can be greater in the proximal side A1 of the longitudinal direction A than in the distal side A2 of the longitudinal direction A.
[0033] In the containment space 2a of the tubular body 2, the transmitted light emitted from the light irradiation unit 51 that passes through the second transmissive part 31 of the expandable body 3 from the inside to the outside in the radial direction C is irradiated onto the drug layer 5 containing the drug 4. As described above, the amount of drug 4 released into the body from the drug layer 5 is greater on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A. Therefore, the degree of reinforcement of the blood vessel wall strength by the drug 4 activated by the light emitted from the light irradiation unit 51 is easier to increase on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A. In other words, with the catheter 100, it is 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. In other words, it is 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.
[0034] 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.
[0035] 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.
[0036] 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.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] 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.
[0041] As described above, the drug layer 5 containing 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 layer 5 containing the drug 4, which is supported on the outer surface 31a of the second permeable portion 31 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.
[0042] As described above, the drug content of the drug layer 5 is greater on the proximal side A1 than on the distal side A2 in the longitudinal direction A. Therefore, the amount of drug 4 released into the body during the drug delivery step S3, that is, the amount of drug 4 delivered to the central adjacent portion X2a of the normal blood vessel portion X2 during the drug delivery step S3, can be increased on the proximal side A1 than on the distal side A2 in the longitudinal direction A.
[0043] 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.
[0044] The ultrasonic element 61 can transmit ultrasonic waves toward the outside in the radial direction C in the accommodation space 2a of the tubular body 2, and can receive the ultrasonic waves reflected and returned. The processing device 80 includes a control unit 81. The control unit 81 calculates the vascular hardness corresponding to each of these plurality of positions based on the ultrasonic waves received by the ultrasonic element 61 at a plurality of positions in the longitudinal direction A, and can output the calculated vascular hardness in association with each of the plurality of positions. Specifically, the control unit 81 can calculate the hardness of the blood vessel wall as the vascular hardness of the diseased blood vessel portion X1 and the normal blood vessel portion X2 in the vicinity of the boundary portion X3 based on the change in blood vessel diameter, blood vessel wall thickness, etc. calculated from the ultrasonic waves received by the ultrasonic element 61. Further, the control unit 81 calculates this vascular hardness at each of the plurality of positions in the longitudinal direction A. Then, the control unit 81 can output the calculated vascular hardness at each position in association with the position information of each position. Thereby, the hardness state of the blood vessel wall in the blood vessel region in the vicinity of the boundary portion X3 can be diagnosed. The control unit 81 may display the vascular hardness associated with the position information on a display unit such as a liquid crystal monitor, for example. The process including the calculation of the vascular hardness at each position is executed by a treatment support device 200 including the catheter 100 and the processing device 80 as shown in FIG. 5.
[0045] The control unit 81 may be a processor such as a general-purpose processor such as a CPU or a 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.
[0046] 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.
[0047] As one variation, instead of matching the heart rate or pulse rate, the ultrasonic element 61 may be moved so that its position in the longitudinal direction A changes at the moment when both the maximum and minimum diameters of the blood vessels have been calculated. For example, the ultrasonic element 61 is used to observe changes in the diameter of the blood vessels, and after identifying both the point where vasoconstriction begins, where the increasing diameter of the blood vessels begins to decrease, and the point where vasodilation begins, where the decreasing diameter of the blood vessels begins to increase, the ultrasonic element 61 is moved 5 mm and the observation is repeated. When the control unit 81 performs the movement operation automatically, the control unit 81 controls the movement of the probe shaft body 60 in the longitudinal direction A within the housing space 2a of the tubular body 2, and acquires ultrasonic information for each of the multiple positions until both the point where vasoconstriction begins and the point where vasodilation begins are identified. The control unit 81 continuously calculates the diameter of the blood vessel from the acquired ultrasonic information, and when it has identified both the vasoconstriction initiation point and the vasodilation initiation point at least once, it controls the movement of the probe shaft body 60 in the longitudinal direction A within the housing 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 vasoconstriction initiation point is the maximum blood vessel diameter when the blood vessel is most dilated in the proximal adjacent portion X2a, which is the treatment site adjacent to the aortic aneurysm, and corresponds to Ds, which is the diameter of the blood vessel during cardiac systole. The diameter of the blood vessel at the vasodilation initiation point is the minimum blood vessel diameter when the blood vessel is most constricted in the proximal adjacent portion X2a, which is the treatment site adjacent to the aortic aneurysm, and corresponds to Dd, which is the diameter of the blood vessel during cardiac diastole. In other words, for each of the multiple positions, the control unit 81 continuously calculates the diameter of the blood vessel from the acquired ultrasonic information and identifies both the vasoconstriction initiation point, where the maximum diameter of the blood vessel changes from increasing to decreasing, and the vasodilation initiation point, where the minimum diameter of the blood vessel changes from decreasing to increasing, at that position. The control unit 81 may, at the timing when it has identified at least once both the vasoconstriction initiation point and the vasodilation initiation point at each of the multiple positions, control the movement of the probe shaft body 60 in the longitudinal direction A within the housing space 2a to move the ultrasonic element 61 to the next position in the longitudinal direction A.
[0048] 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 from the second transmission unit 31 of the expandable body 3 to the outside in the radial direction C, and irradiates the central adjacent part X2a where the drug 4 has been delivered.
[0049] 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 expandable body 3. As shown in FIG. 6, the shaft body 50 includes a connector portion 52 that can be connected 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 capable of emitting the emitted light.
[0050] The emitted light from the light irradiation unit 51 passes through the first penetrating portion 21 of the tubular body 2 and the second penetrating portion 31 of the expandable body 3, and irradiates the drug 4 delivered to the central adjacent portion X2a. As described above, the amount of drug 4 delivered to the central adjacent portion X2a of the normal blood vessel portion X2 in the drug delivery step S3 is greater on the proximal side A1 of the longitudinal direction A than on the distal side A2 of the longitudinal direction A. By utilizing this difference in the amount of drug 4 delivered, the degree of reinforcement of the central adjacent portion X2a by the drug 4 activated by the emitted light from the light irradiation unit 51 can be easily reduced from the side closer to the abdominal aortic aneurysm, which is the diseased blood vessel portion X1, towards the side further away. As a result, the blood vessel wall of the central adjacent portion X2a can be reinforced so that it becomes harder as it approaches the abdominal aortic aneurysm, which is the diseased blood vessel portion X1. As a result, the expansion of the abdominal aortic aneurysm, which is the diseased blood vessel portion X1, can be suppressed. In the immediate vicinity of the boundary X3 of the proximal adjacent portion X2a, the vascular stiffness may be harder than that of the normal vascular portion X2 but softer than that of the diseased vascular portion X1. In this case, it is preferable to increase the amount of drug 4 delivered to the proximal adjacent portion X2a in the proximal A1 of the dilator 3 compared to the distal A2 in the longitudinal direction A, up to the vicinity of the terminal portion of the proximal A1 of the dilator 3, while decreasing it in the proximal A1 of the proximal A1 compared to the distal A2 in the longitudinal direction A at the terminal portion of the proximal A1 of the dilator 3. This makes it possible to more reliably reinforce the vascular stiffness of the portion of the normal vascular portion adjacent to the diseased vascular portion (abdominal aortic aneurysm) so that it approaches the vascular stiffness of the diseased vascular portion as it approaches it.
[0051] In Figure 6, for the sake of explanation, the vessel wall of the proximal adjacent portion X2a, which has been reinforced to become harder as it approaches the abdominal aortic aneurysm (the lesion vessel portion X1) by the light irradiation step S4, is shown with different hatching than the vessel wall of the lesion vessel portion X1 and the vessel wall of the normal vessel portion X2 other than the proximal adjacent portion X2a.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] In this embodiment, the drug 4 is supported on the outer surface 31a of the expander 3 such that the amount of drug 4 released into the body 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 drug 4 may also be supported on the outer surface 31a of the expander 3 such that the amount of drug 4 released into the body increases from the proximal side A1 to the distal side A2 in the longitudinal direction A. In such cases, the catheter body 1 of the catheter 100 is inserted into the aorta with the proximal side A1 being the central side and the distal side A2 being 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 can be inserted into the aorta with the proximal A1 being the distal end and the distal A2 being the central end, and the distal adjacent portion X2b can be reinforced. In this way, the drug 4 may be supported on the outer surface 31a of the expander 3 such that the amount of drug 4 released into the body increases from the proximal A1 to the distal A2 in the longitudinal direction A. Alternatively, the drug 4 may be supported on the outer surface 31a of the expander 3 such that the amount of drug 4 released into the body changes from increasing to decreasing midway along the longitudinal direction A. As described above, the vascular stiffness may be harder than the vascular wall of the normal vascular portion X2 and softer than the lesioned vascular portion X1 in the immediate vicinity of the boundary X3 of the central adjacent portion X2a. In such cases, the amount of drug 4 released into the body may be increased from the distal A2 to the proximal A1 in the longitudinal direction up to the vicinity of the terminal end at the proximal A1 of the expanded body 3, while decreasing from the distal A2 to the proximal A1 in the longitudinal direction at the terminal end at the proximal A1 of the expanded body 3. That is, the drug 4 may be supported on the outer surface 31a of the expanded body 3 such that both regions are formed: a region in the longitudinal direction A where the amount of drug 4 released into the body increases from the distal A2 to the proximal A1 in the longitudinal direction A, and a region in the longitudinal direction A where the amount of drug 4 released into the body increases from the proximal A1 to the distal A2 in the longitudinal direction A.
[0057] As described above, in the catheter 100 of this embodiment, a drug layer 5 containing a drug 4 is supported on the outer surface 31a of the expandable body 3. The drug 4 content in the drug layer 5 differs along the longitudinal direction A, increasing from the distal side A2 to the proximal side A1. In this way, the catheter 100 of this embodiment is configured so that the amount of drug 4 released into the body increases from the proximal side A1 to the distal side A2 along the longitudinal direction A. The difference in the drug 4 content in the drug layer 5 along the longitudinal direction A can be achieved, for example, by varying the thickness of the drug layer 5 in the radial direction C, as shown in Figure 8. Specifically, in Figure 8, the thickness of the drug layer 5 in the radial direction C increases from the distal side A2 to the proximal side A1 along the longitudinal direction A. In this way, the drug 4 content in the drug layer 5 can be increased from the distal side A2 to the proximal side A1 along the longitudinal direction A. However, the amount of drug 4 in the drug layer 5 may be varied depending on the position in the longitudinal direction A, without varying the thickness of the drug layer 5 in the radial direction C.
[0058] Furthermore, in the catheter 100 of this embodiment, the drug 4 is supported on the outer surface 31a of the expander 3, but the configuration is not limited to this. The drug can be contained in the internal space 3a on the radial side C of the expander 3 and released to the outside radial side C of the expander 3 through a plurality of release holes formed in the expander 3. In this case, the internal space 3a of the expander 3 contains a drug solution containing the drug, and the drug is released to the outside radial side C of the expander 3 through a plurality of release holes such that the amount of drug released into the body increases 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. Details of such a configuration will be described later (see Figures 12 to 15). The plurality of release holes may be configured such that the amount of drug 4 released into the body changes from increasing to decreasing at some point along the longitudinal direction A. As described above, the vascular stiffness may be harder than the vascular wall of the normal vascular portion X2 and softer than the lesioned vascular portion X1 in the immediate vicinity of the boundary X3 of the proximal adjacent portion X2a. In such cases, the amount of drug 4 released into the body may be increased from the distal A2 to the proximal A1 in the longitudinal direction up to the vicinity of the terminal portion of the proximal A1 of the expander 3, and then decreased from the distal A2 to the proximal A1 in the longitudinal direction at the terminal portion of the proximal A1 of the expander 3. That is, the drug 4 may be released radially outward from the internal space of the expander through multiple release holes so that both regions are formed: a region in the longitudinal direction A where the amount of drug 4 released into the body increases from the distal A2 to the proximal A1 in the longitudinal direction A, and a region in the longitudinal direction A where the amount of drug 4 released into the body increases from the proximal A1 to the distal A2 in the longitudinal direction A.
[0059] 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 a tubular body 2 as a long body 40 and an expandable body 3. However, the catheter is not limited to this configuration. The catheter 100 may also have a configuration without a shaft body 50. In such a case, the tubular body 2 may be configured to keep the light irradiation unit 51 permanently housed in the housing space 2a. In other words, the tubular body 2 may include a light irradiation unit 51 that is permanently 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 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. In addition, since the light irradiation unit 51 is removed 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.
[0060] 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 a tubular body 2 as a long body 40 and an 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.
[0061] 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 9, 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 9 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.
[0062] 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.
[0063] 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.
[0064] 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.
[0065] In this embodiment, the tubular body 2 has a housing space 2a partitioned inside so as to include the central axis O. Furthermore, the tubular body 2 in this embodiment has a flow path 2b extending along the longitudinal direction A partitioned within the peripheral wall that partitions the housing space 2a.
[0066] 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.
[0067] 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.
[0068] 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.
[0069] 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.
[0070] 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.
[0071] 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.
[0072] 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.
[0073] The expansion body 3 may be attached to the distal end A2 of the tubular body 2 in the longitudinal direction A.
[0074] 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.
[0075] 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.
[0076] 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.
[0077] 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.
[0078] Furthermore, as described above, the second permeable portion 31 of the expandable body 3 in this embodiment has ultrasonic permeability. The second permeable portion 31 having ultrasonic permeability can be realized by using the constituent materials of the second permeable portion 31 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.
[0079] 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.
[0080] Preferably, 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. This allows the light emitted from the light irradiation unit 51 to 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, 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 may be the same as or longer than the length L2 in the longitudinal direction A of the second transmissive unit 31. In other words, the light irradiation unit 51 may be a cylindrical type capable of irradiating light across the entire longitudinal direction A and circumferential direction B of the drug layer 5 containing the drug 4 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 irradiated over the entire area of the drug layer 5 containing the drug 4 in both the longitudinal direction A and the circumferential direction B without rotating the light irradiation unit 51 in the circumferential direction B or moving it in the longitudinal direction A. Therefore, the time required for the light irradiation step S4 (see Figure 6) described above can be shortened.
[0081] However, as shown in Figure 11, the length L1 of the longitudinal direction A from which the circumferential light irradiation unit 51 can emit light outward in the radial direction C may be shorter than the length L2 of the longitudinal direction A of the second transmission unit 31 and shorter than the length of the longitudinal direction A of the drug layer 5 containing the drug 4. In such cases, as described above, in the light irradiation step S4 (see Figure 6), the light irradiation unit 51 can be moved to each of the multiple positions in the longitudinal direction A, and light irradiation can be 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 the entire area of the longitudinal direction A of the drug layer 5. In this case, for example, the light irradiation time at each position may be gradually increased from the distal side A2 to the proximal side A1 in the longitudinal direction A. Also, for example, the light irradiation intensity at each position may be gradually increased from the distal side A2 to the proximal side A1 in the longitudinal direction A. In this way, the degree of reinforcement of the central adjacent portion X2a (see Figures 3 to 7) may be further adjusted.
[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] Furthermore, although the drug 4 in this embodiment is photoreactive and activated by light emitted from the light irradiation unit 51, the drug 4 does not need to be photoreactive as long as it promotes the binding of collagen and elastin in the blood vessel wall. In other words, a non-photoreactive drug 4 may be supported on the outer surface 31a of the expander 3. An example of such a non-photoreactive drug 4 is PGG. "PGG" is an abbreviation for Pentagalloyl Glucose. PGG can bind to elastin in the blood vessel wall and reinforce the stiffness of the blood vessel wall.Furthermore, examples of non-photoreactive drugs 4 include tannic acid, galloylic acid, galloylic acid esters, ellagic acid, proanthocyanidins, anthocyanidins, anthocyanidin glucoside compounds (pelargonidin-3-glucoside, cyanidin-3-glucoside, malvidin-3-glucoside), quercetin, xanthocyanidins, catechins and their derivatives (epicatechin, epigallocatechin, catechin gallate, epicatechin gallate), flavonoids ( Soy isoflavones, genistein, daidzein, glycitein, biocanin), chlorogenic acid, curcumin, resveratrol, polygalloyl compounds (polygalloyl mannose, polygalloyl galactose, polygalloyl xylose, polygalloyl ribose, polygalloyl arabinose, polygalloyl fructose, polygalloyl uinositol, polygalloyl allose, polygalloyl talose, polygalloyl uilludose, polygalloyl guarose, polygalloyl Luertorose, polygalloylthreose, polygalloylulcrose, polygalloyl lactose, polygalloyl maltose, polygalloyl isomaltose, polygalloyl kojibiose, polygalloyl nigerose, polygalloyl laminaribiose, polygalloyl mannobiose, polygalloyl chitobiose, polygalloyl fucosyl lactose, polygalloyl galactobiose, polygalloyl rutinose, polygalloyl neotrehalose, polygalloyl leucose The drugs may be polygalloyl trehalose, polygalloyl cellobiose, polygalloyl sorbitol, polygalloyl mannitol, polygalloyl maltitol, polygalloyl galactitol, polygalloyl fusitol, polygalloyl isomalt, polygalloyl xylitol, polygalloyl ribitol, polygalloyl arabitol, polygalloyl erythritol, polygalloyl treitol, polygalloyl ruiditol, or combinations thereof. When using such non-photoreactive drugs 4, light irradiation of the drug 4 by the light irradiation unit 51 is not required in treatment. In other words, when the catheter 100 is equipped with a non-photoreactive drug 4, the treatment method performed using the catheter 100 does not need to include the light irradiation step S4 (see Figure 6) described above.In other words, after the drug delivery step S3 (see Figure 5) is completed, the post-treatment diagnosis step S5 (see Figure 7) may be performed without performing the light irradiation step S4 (see Figure 6). In this case, during the post-treatment diagnosis step S5, the probe shaft 60 used in the drug delivery step S3 may remain inserted into the housing space 2a of the tubular body 2. Furthermore, if the catheter 100 contains a drug 4 that is not photoreactive, the catheter 100 does not need to have a light irradiation section 51. Moreover, if the catheter 100 contains a drug 4 that is not photoreactive, the tubular body 2 as the elongated body 40 of the catheter body 1 of the catheter 100 does not need to have a first transmissive section 21 that can transmit light emitted from the light irradiation section 51. Furthermore, if the catheter 100 contains a drug 4 that is not photoreactive, the expanded body 3 of the catheter body 1 of the catheter 100 does not need to have a second transmissive section 31 that can transmit light emitted from the light irradiation section 51.
[0089] Furthermore, as described above, the catheter 100 may be configured without a probe shaft body 60. In other words, if the catheter 100 does not have a light irradiation unit 51 and does not have a probe shaft body 60 including an ultrasonic element 61, the elongated body 40 does not need to have a housing space 2a partitioned inside. In other words, the elongated body 40 does not need to be a tubular body 2 that partitions a housing space 2a inside. However, as described above, for the purpose of performing at least one of the drug delivery step S3 (see Figure 5) and the post-treatment diagnosis step S5 (see Figure 7), it is preferable that the catheter 100 has a probe shaft body 60 separate from the catheter body 1. In this view, it is preferable that the elongated body 40 of the catheter body 1 of the catheter 100 is a tubular body 2 that partitions a housing space 2a through which the probe shaft body 60 can be inserted, regardless of whether or not there is a light irradiation unit 51.
[0090] 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.
[0091] The catheter body 1 of the catheter 100 described above has a configuration in which a drug 4 is supported on the outer surface 31a of the expander 3, but it is not limited to this configuration. Figure 12 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 the drug 4 is not supported on the outer surface of the expander 303. Below, these differences will be mainly explained, and the configuration of the catheter body 301 that is common with the catheter body 1 (see Figure 1, etc.) will not be explained.
[0092] As shown in Figure 12, the catheter body 301 comprises a tubular body 2 as a long body 40 and an expandable body 303. The tubular body 2 has the same configuration as the catheter body 1 (see Figure 1, etc.) described above.
[0093] 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 multiple discharge holes 336. More specifically, in the expandable body 303 shown in Figure 12, multiple discharge holes 336 are formed at the position of the second permeable portion 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.
[0094] Figure 13 is an enlarged view of the vicinity of the expandable body 303 in Figure 12. As shown in Figure 13, the internal space 3a of the expandable body 303 can accommodate a drug solution 6 containing the drug 4. The drug 4 can be, for example, the aforementioned dimeric naphthalimide. The drug solution 6 is delivered to the internal space 3a through the flow path 2b of the tubular body 2. The expandable body 303 can expand outward in the radial direction C when the drug solution 6 is delivered to the internal space 3a. Furthermore, the drug solution 6 contained in the internal space 3a can be discharged from the inside to the outside in the radial direction C of the expandable body 303 through a plurality of discharge holes 336 formed in the expandable body 303. In other words, in the catheter body 301 shown in Figures 12 and 13, the drug 4 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 examples shown in Figures 3 to 7) by discharging the drug solution 6 to the outside of the expandable body 303 from the discharge holes 336. In other words, even with the catheter body 301 shown in Figures 12 and 13, the drug delivery step S3 (see Figure 5) can be performed to deliver the drug 4 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 with a drug solution 6 containing the drug 4. That is, even when using the catheter body 301 shown in Figures 12 and 13, the same treatment method as described above using the catheter body 1 (see Figure 1, etc.) (see Figures 2 to 7) can be performed.
[0095] In the drug delivery step S3, performed using the catheter body 301 shown in Figures 12 and 13, the required amount of drug solution 6 contained in the internal space 3a is released to the outside through the discharge port 336. Subsequently, physiological saline is delivered to the internal space 3a of the expandable body 303 through the flow path 2b. This allows the expanded state of the expandable body 303 to be maintained even after the drug 4 contained in the internal space 3a is released through the discharge port 336. Furthermore, by using physiological saline as the fluid contained in the internal space 3a, the part that is irradiated with light (the central adjacent part X2a in the example shown in Figures 3 to 7) can be cooled when performing the light irradiation step S4 (see Figure 6).
[0096] As shown in Figure 13, the number of multiple release holes 336 differs in the longitudinal direction A such that the amount of drug 4 released to the outside of the expander 303 through these release holes 336 increases from one side (distal side A2 in Figure 13) to the other side (proximal side A1 in Figure 13) in the longitudinal direction A. Specifically, the cross-sectional area of each of the multiple release holes 336 shown in Figure 13 is approximately equal. The multiple release holes 336 shown in Figure 13 are formed in the second permeable section 31 such that the number of release holes 336 increases from one side (distal side A2 in Figure 13) to the other side (proximal side A1 in Figure 13) in the longitudinal direction A. In other words, the multiple release holes 336 shown in Figure 13 are formed in the second permeable section 31 such that the distance L3 between two adjacent release holes 336 in the longitudinal direction A decreases from one side of the longitudinal direction A (distal side A2 in Figure 13) to the other side (proximal side A1 in Figure 13). For example, if the region in the longitudinal direction A where the multiple release holes 336 are formed is divided into multiple regions of equal length in the longitudinal direction A, the total number of release holes 336 formed in each of these regions increases from one side of the longitudinal direction A (distal side A2 in Figure 13) to the other side (proximal side A1 in Figure 13). Therefore, the amount of drug 4 released into the body through the multiple release holes 336 can be increased on the other side (proximal side A1 in Figure 13) than on the one side (distal side A2 in Figure 13).
[0097] However, the adjustment of the amount of drug 4 released into the body through the multiple release holes 336 to the outside of the expander 303 in the longitudinal direction A is not limited to the configuration shown in Figure 13, and may be achieved, for example, by making the cross-sectional areas of the multiple release holes 336 different, as shown in Figure 14. Figure 14 shows a modified example of the expander 303 shown in Figure 13. The release holes 336 shown in Figure 14 are formed distributed in the longitudinal direction A such that approximately equal numbers are arranged regardless of their position in the longitudinal direction A. In other words, in Figure 14, the distance L3 between two adjacent release holes 336 in the longitudinal direction A is approximately equal regardless of their position in the longitudinal direction A. In contrast, the cross-sectional areas of the multiple release holes 336 shown in Figure 14 are different in the longitudinal direction A such that the amount of drug 4 released into the body increases from one side of the longitudinal direction A (distal side A2 in Figure 14) to the other side (proximal side A1 in Figure 14). For example, if a region in the longitudinal direction A where multiple release holes 336 are formed is divided into multiple regions of equal length in the longitudinal direction A, the total cross-sectional area of all release holes 336 formed in each of these regions increases from one side of the longitudinal direction A (distal side A2 in Figure 13) to the other side (proximal side A1 in Figure 13). Therefore, the amount of drug 4 released into the body through the multiple release holes 336 can be increased on the other side (proximal side A1 in Figure 13) of the longitudinal direction A compared to the distal side (distal side A2 in Figure 13).
[0098] In Figure 14, the distance L3 between two adjacent discharge holes 336 in the longitudinal direction A is approximately equal regardless of their position in the longitudinal direction A. However, for example, in addition to the cross-sectional area of the multiple discharge holes 336 described above, the distance L3 between two adjacent discharge holes 336 in the longitudinal direction A may be made different depending on their position in the longitudinal direction A, similar to the configuration shown in Figure 13.
[0099] The drug 4 shown in Figures 12 to 14 may or may not be photoreactive, as described above. An example of a non-photoreactive drug 4 is PGG.
[0100] Figure 15 shows another modified example of the expandable body 303 shown in Figure 13. The internal space 3a of the expandable body 303 shown in Figure 15 contains a plurality of drug solution storage spaces 303a to 303d that are not interconnected. Each of these drug solution storage spaces 303a to 303d communicates with the outside of the expandable body 303 in the radial direction C through separate discharge holes 336a to 336d formed at different positions in the longitudinal direction A of the plurality of discharge holes 336. In Figure 15, the internal space 3a of the expandable body 303 contains four drug solution storage spaces 303a to 303d, but the number of drug solution storage spaces is not particularly limited. There may be two to three drug solution storage spaces, or five or more. Also, the plurality of drug solution storage spaces 303a to 303d are arranged side by side in the longitudinal direction A. Furthermore, of the multiple drug solution storage spaces 303a to 303d, two drug solution storage spaces adjacent to each other in the longitudinal direction A are separated by a partition wall 307.
[0101] In the example shown in Figure 15, the drug solution containment space 303a located at the most distal side A2 in the longitudinal direction A is in communication with the outside of the expandable body 303 in the radial direction C through one or more discharge holes 336a. In the example shown in Figure 15, the drug solution containment space 303b adjacent to the drug solution containment space 303a at the proximal side A1 in the longitudinal direction A is in communication with the outside of the expandable body 303 in the radial direction C through one or more discharge holes 336b. In the example shown in Figure 15, the drug solution containment space 303c adjacent to the drug solution containment space 303b at the proximal side A1 in the longitudinal direction A is in communication with the outside of the expandable body 303 in the radial direction C through one or more discharge holes 336c. In the example shown in Figure 15, the drug solution containment space 303d adjacent to the proximal side A1 in the longitudinal direction A with respect to the drug solution containment space 303c, that is, the drug solution containment space 303d located at the most proximal side A1 in the longitudinal direction A, is in communication with the radially C outside of the expandable body 303 through one or more discharge holes 336d.
[0102] Here, the multiple drug solution storage spaces 303a to 303d can separately contain multiple drug solutions 6a to 6d with different concentrations of drug 4, such that the amount of drug 4 released into the body from the expanded body 303 increases from one side (distal side A2 in Figure 15) to the other side (proximal side A1 in Figure 15) of the longitudinal direction A. Each of the drug solutions 6a to 6d may be delivered to the corresponding drug solution storage space among the multiple drug solution storage spaces 303a to 303d, for example, through separate channels 2c to 2f formed in the tubular body 2. The concentration of drug 4 is, for example, lowest in drug solution 6a, increasing in the order of drug solution 6b, drug solution 6c, and highest in drug solution 6d. In this case, drug solution 6a is stored in the drug solution storage space 303a on the most distal side A2. Drug solution 6b is stored in drug solution storage space 303b. Furthermore, drug solution 6c is contained in drug solution containment space 303c. Additionally, drug solution 6d is contained in the most proximal drug solution containment space 303d at A1. In this way, the amount of drug 4 released into the body from the expander 303 can be increased from one side (distal A2 in Figure 15) to the other side (proximal A1 in Figure 15) of the proximal A1 and distal A2 in the longitudinal direction A. By using multiple drug solutions 6a to 6d with different concentrations of drug 4, the degree of reinforcement of the proximal adjacent portion X2a (see Figure 3, etc.) can be easily reduced from the side closer to the abdominal aortic aneurysm (the lesioned vessel X1) towards the side further away. This allows the vessel wall of the proximal adjacent portion X2a to be reinforced so that it becomes harder as it approaches the abdominal aortic aneurysm (the lesioned vessel X1). As a result, the expansion of the abdominal aortic aneurysm (the lesioned vessel X1) can be suppressed.
[0103] This disclosure relates to catheters, treatment support devices, and treatment methods.
[0104] 1, 301: Catheter body 2: Tubular body (example of a long body) 2a: Housing space 2a1: Proximal opening 2a2: Distal opening 2b-2f: Flow path 2b1: Proximal opening 2b2: Distal opening 3, 303: Expanded body 3a: Internal space 4: Drug 5: Drug layer 6, 6a-6d: Drug solution 21: First permeation section 22: Tubular body 23: Hub 23a: Fluid supply / discharge port 24: Valve body 31: Second permeation section 31a: Outer surface of the second permeation section (example of the outer surface of the expanded body) 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 40: Long body 50: Shaft body 51: Light irradiation section 52: Connector section 53: Shaft body 60: Probe shaft body 61: Ultrasonic element 62: Connector part 63: Probe shaft body 64: Electrical signal line 80: Processing unit 81: Control unit 82: First drive unit 83: Second drive unit 90: Light source device 100: Catheter 200: Treatment support device 303a-303d: Liquid containment space 307: Partition 336, 336a-336d: 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 part L2: Length in the longitudinal direction of the second transmission part L3: Distance between two adjacent discharge ports O: Central axis of the tubular body X1: Lesion vessel part X2: Normal vascular portion X2a: Proximal adjacent portion (an example of the portion of the normal vascular portion adjacent to the diseased vascular portion) X2b: Peripheral adjacent portion (an example of the portion of the normal vascular portion adjacent to the diseased vascular portion) X3: Boundary
Claims
1. A catheter comprising: an elongated body; an expandable body covering the radially outer surface of the elongated body and capable of expanding and contracting in the radial direction; and a drug supported on the outer surface which is the radially outer surface of the expandable body, or housed in the radially inner internal space of the expandable body, and capable of being released to the radially outer side of the expandable body through a plurality of release holes formed in the expandable body, wherein the drug is supported on the outer surface of the expandable body, or can be released from the internal space of the expandable body to the radially outer side of the expandable body through the plurality of release holes, such that the amount of drug released from the expandable body toward a living organism increases from the proximal to distal side in the longitudinal direction of the elongated body, or from the distal to proximal side in the longitudinal direction.
2. The catheter according to claim 1, wherein a drug layer containing the drug is supported on the outer surface of the expandable body, and the drug content of the drug layer differs in the longitudinal direction such that the amount of drug released increases from the proximal to the distal side in the longitudinal direction, or from the distal to the proximal side in the longitudinal direction.
3. The catheter according to claim 1, wherein the internal space of the expandable body is capable of containing a drug solution containing the drug, and at least one of the cross-sectional area of the plurality of discharge holes and the number of the plurality of discharge holes differs in the longitudinal direction such that the amount of drug discharged increases from the proximal side to the distal side in the longitudinal direction, or from the distal side to the proximal side in the longitudinal direction.
4. The catheter according to claim 1, wherein the internal space of the expandable body includes a plurality of drug solution containing spaces that are not in communication with each other, each of the plurality of drug solution containing spaces is in communication with the radially outside of the expandable body through separate discharge holes formed at different positions in the longitudinal direction among the plurality of discharge holes, and the plurality of drug solution containing spaces can separately contain a plurality of drug solutions with different concentrations of the drug such that the amount of the drug discharged increases from the proximal side to the distal side in the longitudinal direction, or from the distal side to the proximal side in the longitudinal direction.
5. The catheter according to any one of claims 1 to 4, wherein the elongated body is tubular, and comprises a probe shaft body that can be inserted through the tubular body, and the probe shaft body comprises an ultrasonic element.
6. The catheter according to any one of claims 1 to 4, wherein the elongated body is a tubular body that internally partitions a housing space that houses or can house a light irradiation unit, the tubular body has a first permeable portion at a position where its radially outer side is covered 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 permeable portion which is capable of transmitting the emitted light that has passed through the first permeable portion of the tubular body to the radially outer side, and the drug is capable of being activated by the emitted light from the light irradiation unit.
7. The catheter according to claim 6, 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.
8. The catheter according to claim 7, further comprising a probe shaft body that can be inserted through the tubular body, wherein the probe shaft body comprises an ultrasonic element.
9. The catheter according to claim 7, wherein the shaft body further comprises an ultrasonic element near the light irradiation portion.
10. 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.
11. A treatment method performed using a catheter according to any one of claims 1 to 4, comprising: a catheter delivery step of delivering the expander to a boundary between a diseased blood vessel and a normal blood vessel; and a drug delivery step of expanding the expander to deliver the drug to a portion of the normal blood vessel adjacent to the diseased blood vessel.
Citation Information
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