Light irradiation medical device

Abstract

To provide a light irradiation medical device that can suppress heat generation by light absorption and achieve good visibility in the body.SOLUTION: A light irradiation medical device 1 includes a shaft 10 having a distal end 101 and a proximal end 102 in a longitudinal axis direction, and having a lumen 100 extending in the longitudinal axis direction. The shaft 10 includes a first region 11 and a second region 12 on a proximal side with respect to the first region 11, with light transmissivity lower than that of the first region 11. In the second region 12, the chromaticity a* in the L*a*b* colorimetric system is 35 to 60, and the hue angle h is -45° to 45°.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light irradiation medical device for irradiating light onto tissues containing cancer cells and the like in body lumens such as blood vessels and the digestive tract. [Background technology]

[0002] In photodynamic therapy (PDT), a photosensitizer is administered intravenously or intraperitoneally, allowing it to accumulate in target tissues such as cancer cells, and then irradiated with light of a specific wavelength to excite the photosensitizer. When the excited photosensitizer returns to its ground state, energy conversion occurs, generating reactive oxygen species. The reactive oxygen species attack the target tissue, allowing it to be removed. In addition, laser light-based ablation (tissue cauterization) is performed by irradiating the target tissue with laser light to cauterize it.

[0003] In photoirradiation medical devices used for photoablation such as PDT and photoimmunotherapy, a light guide material is placed inside a catheter tube to irradiate the target tissue with light.

[0004] Patent Document 1 describes a device including a balloon catheter with a defined treatment window that delivers radiation to a defined area. The device has a transparent central channel through which a fiber optic probe can be inserted and an outer sleeve with a proximal end and a distal end used to inflate the balloon. The outer sleeve further includes an inflatable balloon near the distal end, the balloon coated at both ends with a reflective material to define the treatment window.

[0005] Patent document 2 describes a laser side irradiator characterized by comprising: a flexible outer tube; an optical fiber inserted into the outer tube so that it can rotate circumferentially; an optical chip arranged at the tip of the outer tube so that its base end face faces the tip face of the optical fiber and having a reflective surface formed at the tip portion that can totally reflect laser light incident from the optical fiber in a specific lateral direction; a sleeve that restrains the optical chip at the tip portion of the optical fiber and is housed within the tip portion of the outer tube; a mark provided on the sleeve; and means for detecting the position of the mark. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-46640 [Patent Document 2] Japanese Patent Application Publication No. 10-26709 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the devices described in Patent Documents 1 and 2 above still have room for improvement in terms of functionality for suppressing heat generation caused by the catheter absorbing light used in treatment and in terms of visibility.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a light irradiation medical device that can suppress heat generation due to light absorption and has good visibility inside the body. [Means for solving the problem]

[0009] One embodiment of the light irradiation medical device of the present invention that can solve the above problems is as follows. [1] A shaft having a distal end and a proximal end in a longitudinal direction and an inner lumen extending in the longitudinal direction, the shaft having a first region and a second region proximal to the first region and having a light transmittance lower than that of the first region, the second region being L* a * b * Chromaticity a according to the color system * A light irradiation medical device having a hue angle h of 35 to 60 and a hue angle h of -45° to 45°. With the above configuration, when the photoirradiation medical device is used for phototherapy, the amount of therapeutic light absorbed in the second region can be reduced, thereby suppressing heat generation in the second region. This prevents burns to the treatment site (target tissue) and melting of the second region. Furthermore, the reduction in the amount of light reaching the treatment site can be suppressed, allowing for effective light irradiation of the treatment site. Furthermore, the presence of the second region improves the visibility of the photoirradiation medical device within the body, making it easier to adjust the position of the treatment site and the photoirradiation medical device. [2] The photoirradiation medical device according to [1], wherein the length of the second region on the outer surface of the shaft in the longitudinal direction is longer than the length of the first region on the outer surface of the shaft in the longitudinal direction. [3] The light irradiation medical device according to [1] or [2] further comprises a light-guiding material that is arranged in the inner cavity of the shaft so as to be movable in the longitudinal axis direction and that emits light, and the wavelength of the light emitted by the light-guiding material is 600 nm or more and 700 nm or less. [4] A light irradiation medical device described in any one of [1] to [3], in which the first section of the shaft from the proximal end of the first region to a point 10 cm proximal to the proximal end of the first region has a light transmittance of 90% or more as determined by the light transmittance measurement method described below. [Light transmittance measurement method] (1) The optical fiber diffuser connected to the light source (ML6600, Modulight) was inserted into an integrating sphere (CSTM Flux 6, Labsphere) from its distal end to 10 cm proximal to the distal end of the optical fiber diffuser. (2) Light with a wavelength of 660 nm or more and 670 nm or less is emitted from the optical fiber diffuser, and the radiant flux Ir is measured using a light intensity measuring device (FLAME-S, Ocean Photonics) connected to an integrating sphere. (3) The optical fiber diffuser is placed in the lumen of the shaft so that the distal end of the first section coincides with the distal end of the optical fiber diffuser, and the entire shaft except for the first section is covered with silver foil. (4) The shaft that has been subjected to step (3) is inserted into the integrating sphere from the distal end of the first section to the proximal end of the first section. (5) Light with a wavelength of 660 nm or more and 670 nm or less is emitted from the optical fiber diffuser that has undergone steps (3) and (4), and the radiant flux Is is measured using a light intensity measuring device connected to an integrating sphere. (6) The value obtained by the formula Is / Ir is defined as the light transmittance of the first section. [5] The photoirradiation medical device according to any one of [1] to [4], wherein an extension portion that extends in the radial direction of the shaft is further provided at the distal portion of the shaft. [6] The light irradiation medical device according to [5], wherein the expansion section is a balloon, and the second region is present in a portion of the shaft that is disposed in the inner cavity of the balloon. [7] A light irradiation medical device according to [5], further comprising an outer shaft having an inner cavity extending in the longitudinal direction of the shaft, the shaft being disposed in the inner cavity of the outer shaft. [8] A light irradiation medical device as described in [7], which has a proximal fixing portion where the proximal end of the extension portion and the outer shaft are fixed, and the second region is located on the shaft distal to the position where the proximal fixing portion is located. [9] The outer shaft is L * a * b * Chromaticity a according to the color system * The light irradiation medical device according to [7] or [8], wherein the range of hue angle is 35 or more and 60 or less, and the range of hue angle h is -45° or more and 45° or less.

[10] The photoirradiation medical device according to any one of [5] and [7] to [9], wherein the expansion part is a balloon, a basket, or a self-expanding stent. [Effects of the Invention]

[0010] When used in phototherapy, the photoirradiation medical device of the present invention can reduce the amount of therapeutic light absorbed in the second region, thereby suppressing heat generation in the second region. This prevents burns to the treatment site (target tissue) and melting of the second region. Furthermore, it can suppress a decrease in the amount of light reaching the treatment site, allowing for effective light irradiation of the treatment site. Furthermore, the presence of the second region improves the visibility of the photoirradiation medical device within the body, making it easier to adjust the position of the treatment site and the photoirradiation medical device. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view (partial side view) of a photoirradiation medical device according to an embodiment of the present invention. [Figure 2] FIG. 10 is a cross-sectional view (partial side view) showing a modified example of the photoirradiation medical device according to the embodiment of the present invention. [Figure 3] FIG. 10 is a cross-sectional view (partial side view) showing another modified example of the photoirradiation medical device according to the embodiment of the present invention. [Figure 4] 4 is a cross-sectional end view of the light irradiation medical device shown in FIG. 1 taken along line IV-IV. [Figure 5] 3 is a cross-sectional end view of the light irradiation medical device shown in FIG. 2 taken along line VV. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the illustrated examples, and appropriate modifications may be made within the scope of the spirit described above and below, and all such modifications are within the technical scope of the present invention. In the drawings, hatching and symbols may be omitted for convenience. In such cases, reference should be made to the specification and other drawings. Furthermore, the dimensions of various parts in the drawings may differ from the actual dimensions, as priority is given to helping understand the features of the present invention.

[0013] A photoirradiation medical device according to one embodiment of the present invention includes a shaft having a distal end and a proximal end in a longitudinal axis direction and an inner cavity extending in the longitudinal axis direction, the shaft having a first region and a second region proximal to the first region and having a light transmittance lower than that of the first region, and the second region is L * a * b * Chromaticity a according to the color system * The gist of the invention is that the value of the hue angle is between 35 and 60, and the hue angle is between -45° and 45°.

[0014] Photoirradiation medical devices are used in PDT and photoablation to irradiate a treatment site, which is a target tissue such as cancer cells, with light of a specific wavelength in a body lumen such as a blood vessel or the digestive tract. The photoirradiation medical device may be delivered to the treatment site alone or may be used together with a delivery catheter or endoscope. In endoscopic treatment, the photoirradiation medical device is placed inside the body through the forceps channel of the endoscope and delivered to the treatment site.

[0015] The basic configuration of a light irradiation medical device will be described with reference to FIGS. 1 to 5. FIG. 1 shows a cross-sectional view (partially a side view) of a light irradiation medical device according to an embodiment of the present invention. FIG. 2 shows a cross-sectional view (partially a side view) of a modified light irradiation medical device according to an embodiment of the present invention. FIG. 3 shows a cross-sectional view (partially a side view) of another modified light irradiation medical device according to an embodiment of the present invention. FIG. 4 shows a cross-sectional end view of the light irradiation medical device shown in FIG. 1 taken along line IV-IV. FIG. 5 shows a cross-sectional end view of the light irradiation medical device shown in FIG. 2 taken along line VV. The light irradiation medical device shown in FIGS. 1 to 3 has a shaft 10. In each drawing, the left side of the paper corresponds to the distal side of the shaft 10, and the right side of the paper corresponds to the proximal side of the shaft 10.

[0016] In this specification, the proximal side refers to the side closest to the user in the direction of extension of the shaft, and the distal side refers to the side opposite the proximal side, i.e., the side to be treated. The distal portion of the shaft refers to the distal half of the shaft, and the proximal portion of the shaft refers to the proximal half of the shaft. The direction of extension of the shaft is also referred to as the longitudinal axis direction. The radial direction refers to the radial direction of the shaft, and in this specification, the inward direction refers to the radial direction toward the axial center of the shaft, and the outward direction refers to the direction opposite the inward direction.

[0017] The materials of the components constituting the photoirradiation medical device 1 are preferably biocompatible.

[0018] The photoirradiation medical device 1 includes a shaft 10. The shaft 10 is a member having a distal end 101 and a proximal end 102 in the longitudinal direction, and having a lumen 100 extending in the longitudinal direction. The shaft 10 may have multiple lumens 100, but preferably has only one lumen 100. The shape of the shaft 10 is not particularly limited as long as the lumen 100 is present, and may be, for example, a hollow cylindrical shape or a hollow polygonal prism shape. A tubular structure is preferable in order to place a light-guiding material 20 (described later) in the lumen 100. Hereinafter, a cross section perpendicular to the longitudinal direction of the lumen 100 of the shaft 10 will be referred to as a lumen cross section.

[0019] The shape of the cross section of the lumen of the shaft 10 is not particularly limited, and may be, for example, a circle, an oval, a polygon, a star, or a combination of these. Note that the oval shape includes an ellipse, an egg, and a rounded rectangle, and the same applies when the oval shape is referred to in the following description.

[0020] The shaft 10 is preferably flexible, which allows the shaft 10 to be deformed to fit the shape of the vessel in the living body. In addition, the shaft 10 is preferably elastic in order to maintain its shape.

[0021] Examples of the shaft 10 include a hollow body formed by arranging one or more wires in a predetermined pattern; a hollow body with a resin coating on at least one of the inner and outer surfaces; a resin tube; or a combination of these, such as a combination of these connected in the longitudinal direction. Examples of hollow bodies with wires arranged in a predetermined pattern include a cylindrical body with a mesh structure formed by simply crossing or weaving wires, and a coil formed by winding wires. The wires may be one or more solid wires or one or more twisted wires. The resin tube can be manufactured, for example, by extrusion molding.

[0022] The shaft 10 can be made of, for example, synthetic resins such as polyolefin resins (e.g., polyethylene and polypropylene), polyamide resins (e.g., nylon), polyester resins (e.g., PET), aromatic polyether ketone resins (e.g., PEEK), polyether polyamide resins, polyurethane resins, polyimide resins, and fluororesins (e.g., PTFE, PFA, and ETFE), or metals such as stainless steel, carbon steel, and nickel-titanium alloys. These materials may be used alone or in combination of two or more.

[0023] The shaft 10 may have a single-layer structure or a multi-layer structure. When the shaft 10 has a multi-layer structure, for example, the shaft 10 may have a resin tube that forms an intermediate layer made of a metal braid such as stainless steel, carbon steel, or a nickel-titanium alloy.

[0024] The shaft 10 preferably contains an optically transparent material. This allows light to be efficiently irradiated onto the target tissue when the light-guiding member 20 is placed inside the shaft 10. Examples of optically transparent materials include synthetic resins such as (meth)acrylic resins (e.g., polymethyl methacrylate (PMMA)), polycarbonate resins (e.g., polydiethylene glycol bisallyl carbonate (PC)), polystyrene-based resins (e.g., methyl methacrylate-styrene copolymer resin (MS), acrylonitrile styrene resin (SAN)), polyamide resins (e.g., nylon), and polyolefin resins.

[0025] The shaft 10 preferably contains a light-diffusing material, which allows the light emitted from the light-guiding material 20 to be appropriately diffused as it passes through the shaft 10, making it easier to evenly irradiate the target tissue with light. Examples of light-diffusing materials include inorganic particles such as titanium oxide, barium sulfate, and calcium carbonate, and organic particles such as cross-linked acrylic particles and cross-linked styrene particles.

[0026] The shaft 10 has a first region 11. The first region 11 preferably has a higher light transmittance than the other portions of the shaft 10. It is more preferable that the first region 11 has a higher light transmittance of the therapeutic light used than the other portions of the shaft 10. The first region 11 is preferably transparent, and the first region 11 may be configured, for example, by disposing a transparent member therein.

[0027] The first region 11 may be provided only in a part of the circumferential direction of the shaft 10. The first region 11 may be provided over the entire circumferential direction of the shaft 10.

[0028] When the first region 11 is provided only in a portion of the circumference of the shaft 10, the shape of the first region 11 when viewed from the radial direction of the shaft 10 can be, for example, circular, elliptical, polygonal, or a combination of these.

[0029] When the first region 11 is provided over the entire circumferential direction of the shaft 10, it may be formed into a shape such as a hollow cylinder or a hollow polygonal column. In order to place the light-guiding material 20 in the lumen, the first region 11 preferably has a tubular structure. With this configuration, light emitted from the light-guiding material 20 placed in the lumen of the first region 11 can be irradiated toward the entire outside of the shaft 10.

[0030] The first region 11 may be made of a material such as the resin that constitutes the shaft 10, or a synthetic resin such as a (meth)acrylic resin (e.g., polymethyl methacrylate (PMMA)), a polycarbonate resin (e.g., polydiethylene glycol bisallyl carbonate (PC)), a polystyrene-based resin (e.g., methyl methacrylate-styrene copolymer resin (MS), acrylonitrile styrene resin (SAN)), a polyamide resin (e.g., nylon), or a polyolefin resin. These materials may be used alone or in combination.

[0031] The first region 11 can be provided in one or more locations on the shaft 10, but it is preferable that only one first region 11 is provided on one shaft 10 in order to make it easier to adjust the irradiation position of the light emitted from the light-guiding material 20.

[0032] The first region 11 is preferably present in the distal portion of the shaft 10. However, the first region 11 may be present in the proximal portion of the shaft 10. The first region 11 may be present only in the distal portion of the shaft 10.

[0033] It is preferable that the length of the first region 11 in the longitudinal direction on the outer surface of the shaft 10 is longer than the length of the first region 11 in the circumferential direction on the outer surface of the shaft 10. This makes it easier to irradiate the treatment area, such as a lesion extending along the longitudinal direction of the biological duct wall, with therapeutic light. When comparing the above lengths, the shortest length of the first region 11 in the circumferential direction on the outer surface of the shaft 10 is compared with the shortest length of the first region 11 in the longitudinal direction on the outer surface of the shaft 10.

[0034] The shaft 10 has a second region 12 located proximal to the first region 11 and having a lower light transmittance than the first region 11 .

[0035] The second region 12 preferably has a lower optical transmittance than the first region 11 for light used in treatment.

[0036] The wavelength of the light used for the treatment may be set appropriately depending on the treatment target, but for example, light with a wavelength of 600 nm or more and 700 nm or less may be used as the light used for the treatment.

[0037] The second region 12 is L * a * b * Chromaticity a according to the color system * The chromaticity a of the second region 12 is 35 or more and 60 or less. * The chromaticity a of the second region 12 is more preferably 38 or more, and further preferably 40 or more. * is more preferably 58 or less, and even more preferably 55 or less. This configuration can facilitate suppression of absorption of therapeutic light and also improve the visibility of the second region 12.

[0038] The second region 12 has a hue angle h of -45° or more and 45° or less. * a * b * Color space a * and b * From the value of h=tan[(b* ) / (a * ) is calculated using the following formula: The hue angle h of the second region 12 is preferably −40° or greater, and more preferably −30° or greater. The hue angle h of the second region 12 is preferably 40° or less, and even more preferably 30° or less. This configuration can more easily suppress absorption of therapeutic light and also improve the visibility of the second region 12.

[0039] Lightness L of the second region 12 * is preferably 10 or more, more preferably 15 or more, and even more preferably 20 or more. * is preferably not more than 90, more preferably not more than 85, and even more preferably not more than 80. This configuration can facilitate suppression of absorption of therapeutic light and also improve the visibility of the second region 12.

[0040] L in the second region 12 of the photoirradiation medical device 1 * a * b * Color representation by color system L * , a * , b * can be measured by a colorimeter.

[0041] Specific colors of the second region 12 may be, for example, red, orange, pink, purple, or the like.

[0042] The second region 12 may be provided in only one location on the shaft 10, or may be provided in multiple locations.

[0043] The second region 12 may be provided only in a part of the circumferential direction of the shaft 10. The second region 12 may be provided over the entire circumferential direction of the shaft 10.

[0044] When the second region 12 is provided only in a portion of the circumference of the shaft 10, the shape of the second region 12 when viewed from the radial direction of the shaft 10 can be, for example, circular, elliptical, polygonal, or a combination of these.

[0045] When the second region 12 is provided over the entire circumferential direction of the shaft 10, it may have a shape such as a hollow cylinder or a hollow polygonal pillar. In order to place the light-guiding material 20 in the lumen, the second region 12 preferably has a tubular structure.

[0046] The second region 12 is preferably present in the distal portion of the shaft 10, but may be present only in the distal portion of the shaft 10. Alternatively, the second region 12 may be present in the proximal portion of the shaft 10.

[0047] The shaft 10 may be composed of only the first region 11 and the second region 12. In addition to the first region 11 and the second region 12, the shaft 10 may further include a region having properties different from the first region 11 and the second region 12. However, it is preferable that the portion of the shaft 10 in contact with the first region 11 does not have a white or black portion, and it is more preferable that the distal portion of the shaft 10 does not have a white or black portion. Alternatively, the entire shaft 10 may be configured to have no white or black portions.

[0048] It is preferable that the first region 11 and the second region 12 are adjacent to each other. This configuration makes it easier to visually recognize the boundary between the first region 11 and the second region 12. This makes it easier to position the first region 11 at the treatment site. Furthermore, the improved visibility of the boundary between the first region 11 and the second region 12 makes it easier to adjust the position of the first region 11 and the position of the light-guiding material 20 when inserting the light-guiding material 20 into the lumen of the shaft 10. This shortens the time required for treatment.

[0049] The length of the second region 12 on the outer surface of the shaft 10 in the longitudinal direction of the shaft 10 is preferably longer than the length of the first region 11 on the outer surface of the shaft 10 in the longitudinal direction of the shaft 10. This makes it easier to improve the visibility of the shaft 10 within the body. Here, when comparing the above lengths, the shortest length of the second region 12 on the outer surface of the shaft 10 in the longitudinal direction of the shaft 10 is compared with the shortest length of the first region 11 on the outer surface of the shaft 10 in the longitudinal direction of the shaft 10.

[0050] As described above, the light irradiation medical device 1 includes a shaft 10 having a distal end 101 and a proximal end 102 in the longitudinal direction and an inner cavity 100 extending in the longitudinal direction, and the shaft 10 has a first region 11 and a second region 12 proximal to the first region 11 and having a light transmittance lower than that of the first region 11, and the second region 12 has a light transmittance of L * a * b * Chromaticity a according to the color system * By configuring the second region 12 so that the y-axis angle is 35 to 60 and the hue angle h is -45° to 45°, when the photoirradiation medical device 1 is used for phototherapy, the amount of therapeutic light absorbed by the second region 12 can be reduced, thereby suppressing heat generation in the second region 12. This prevents burns to the treatment site (target tissue) and melting of the second region 12. Furthermore, a reduction in the amount of light reaching the treatment site can be suppressed, allowing for effective light irradiation of the treatment site. Furthermore, the presence of the second region 12 improves the visibility of the photoirradiation medical device 1 within the body, making it easier to adjust the position of the treatment site and the position of the photoirradiation medical device 1.

[0051] As shown in Figure 2, the distal end of the shaft 10 is preferably closed. By closing the distal end of the shaft 10, it is possible to prevent body fluids such as digestive tract mucus and blood from entering the lumen of the shaft 10, which would otherwise cause deterioration of the light-guiding material 20 (described below). As shown in Figure 2, a distal tip 60 may be attached to the distal end 101 of the shaft 10. This makes it possible to avoid damage to biological tissue caused by the distal end of the shaft 10. Examples of the shape of the distal tip 60 include a cylindrical shape, an elongated cylindrical shape, a hemispherical shape, an elongated spheroidal shape, a truncated pyramid shape, a truncated cone shape, an elongated truncated cone shape, a truncated rounded cone shape, and combinations thereof.

[0052] Preferably, the light irradiation medical device 1 further comprises a light guide member 20 that is arranged in the inner cavity 100 of the shaft 10 so as to be movable in the longitudinal direction of the shaft 10 and that emits light.

[0053] The light-guiding material 20 functions as a light transmission path for carrying incident light. An optical fiber can be used as the light-guiding material 20. The optical fiber has a core and a cladding 22 that covers the radially outer side of the core, and preferably has a cladding-free portion 21 in a part distal to the core. There are no particular limitations on the material that constitutes the core and cladding 22, and plastic, quartz glass, fluoride glass, or other glass can be used.

[0054] The cladding-free portion 21 refers to at least a portion of the circumferential direction of the core where the cladding 22 is not present, and serves as the light-emitting area of ​​the optical fiber 20. By providing such a cladding-free portion 21, a side-illumination type light irradiation medical device 1 can be configured.

[0055] The position where the cladding-free portion 21 is provided in the longitudinal direction of the shaft 10 is not particularly limited as long as it is a part of the distal portion of the core, but it is preferably provided in a part including the distal end of the core. This makes it easier to form the cladding-free portion 21 and can also increase the flexibility of the distal end portion of the light-guiding material 20.

[0056] The position of the distal end of cladding-free portion 21 preferably coincides with the position of the distal end of the core, which eliminates the need for the difficult process of forming cladding-free portion 21 while leaving cladding 22 in a portion including the distal end of the optical fiber, thereby facilitating the process of forming the light-emitting area of ​​the optical fiber.

[0057] The cladding-free portion 21 can be formed by removing the cladding 22 by, for example, etching or polishing. It is more preferable to roughen the outer surface of the cladding-free portion 21 by a method such as sanding, which can improve light diffusion.

[0058] The length of the cladding-free portion 21 in the longitudinal direction of the shaft 10 can be configured to be shorter than the length of the first region 11 in the longitudinal direction on the outer surface of the shaft 10. Here, when comparing the above lengths, the shortest length of the cladding-free portion 21 in the longitudinal direction of the shaft 10 is compared with the shortest length of the first region 11 in the longitudinal direction on the outer surface of the shaft 10.

[0059] When using the light irradiation medical device 1, it is preferable to insert the light-guiding material 20 into the inner cavity of the shaft 10 and move the light-guiding material 20 in the longitudinal direction of the shaft 10 to the position where the first region 11 is located, as shown in Figures 2, 3, and 5.

[0060] It is preferable that the section in the longitudinal direction of the shaft 10 where the first region 11 exists overlaps with the section in the longitudinal direction of the shaft 10 where the cladding-free portion 21 exists. In this case, it is sufficient that the section in the longitudinal direction of the shaft 10 where the first region 11 exists overlaps with the section in the longitudinal direction of the shaft 10 where the cladding-free portion 21 exists, but it is more preferable that they overlap entirely. A part of the section in the longitudinal direction of the shaft 10 where the first region 11 exists may overlap with the entire section in the longitudinal direction of the shaft 10 where the cladding-free portion 21 exists. This configuration makes it easier for light emitted from the light-guiding material 20 to pass through the first region 11, making it easier to efficiently irradiate the treatment area.

[0061] The light irradiation medical device 1 further includes a light-guiding material 20 that is arranged in the inner cavity 100 of the shaft 10 so as to be movable in the longitudinal axis direction of the shaft 10 and that emits light, and it is preferable that the wavelength of the light emitted by the light-guiding material 20 is 600 nm or more and 700 nm or less.

[0062] As described above, the wavelength of the light emitted from the light-guiding material 20 is preferably 600 nm or more and 700 nm or less. This means that the emitted light preferably contains light with a wavelength of 600 nm or more and 700 nm or less. For example, light with a wavelength less than 600 nm may be temporarily emitted. Furthermore, light with a wavelength greater than 700 nm may be temporarily emitted. From the perspectives of improving the effectiveness of treatment and of easily suppressing light absorption in the second region 12, it is more preferable that the light emitted from the light-guiding material 20 be only light with a wavelength of 600 nm or more and 700 nm or less. By configuring the wavelength of the light emitted from the light-guiding material 20 as described above, the amount of light absorbed by the second region 12 of the photoirradiation medical device 1 can be easily reduced, thereby making it easier to suppress heat generation in the second region 12 of the photoirradiation medical device 1.

[0063] Preferably, the distal portion of the shaft 10 is further provided with an expansion section 30 that expands in the radial direction of the shaft 10. As shown in Figures 2 and 3, the expansion section 30 preferably expands outward in the radial direction of the shaft 10 at the distal portion of the shaft 10. Expanding the expansion section 30 makes it easier to fix the light irradiation medical device 1 inside the body, for example, to the wall of a biological tube, thereby preventing displacement of the light irradiation medical device 1 inside the body.

[0064] As shown in FIG. 3 , the photoirradiation medical device 1 preferably further includes an outer shaft 40 having a lumen 400 extending in the longitudinal direction of the shaft 10. The outer shaft 40 is preferably disposed so as to have a distal end and a proximal end in the longitudinal direction of the shaft 10. The outer shaft 40 may have multiple lumens 400, but preferably has only one lumen 400. The shape of the outer shaft 40 is not particularly limited as long as the lumen 400 is present, but may be, for example, a hollow cylindrical shape or a hollow polygonal prism shape. A tubular structure is preferable so that the shaft 10 can be disposed in the lumen 400. Hereinafter, a cross section perpendicular to the longitudinal direction of the lumen 400 of the outer shaft 40 will be referred to as a lumen cross section.

[0065] The cross-sectional shape of the inner cavity of the outer shaft 40 is not particularly limited, but may be, for example, a circle, an oval, a polygon, a star, or a combination of these.

[0066] The outer shaft 40 is preferably flexible, which allows the outer shaft 40 to be deformed to fit the shape of the vessel inside the living body. In addition, the outer shaft 40 is preferably elastic in order to maintain its shape.

[0067] Examples of the outer shaft 40 include a hollow body formed by arranging one or more wires in a predetermined pattern; a hollow body with a resin coating on at least one of the inner and outer surfaces; a resin tube; or a combination of these, such as a combination of these connected in the longitudinal direction. Examples of hollow bodies with wires arranged in a predetermined pattern include a cylindrical body with a mesh structure formed by simply crossing or weaving wires, and a coil formed by winding wires. The wires may be one or more solid wires or one or more twisted wires. The resin tube can be manufactured, for example, by extrusion molding.

[0068] The outer shaft 40 can be made of, for example, synthetic resins such as polyolefin resins (e.g., polyethylene and polypropylene), polyamide resins (e.g., nylon), polyester resins (e.g., PET), aromatic polyether ketone resins (e.g., PEEK), polyether polyamide resins, polyurethane resins, polyimide resins, and fluororesins (e.g., PTFE, PFA, and ETFE), or metals such as stainless steel, carbon steel, and nickel-titanium alloys. These materials may be used alone or in combination of two or more.

[0069] The outer shaft 40 may have a single-layer structure or a multi-layer structure. When the outer shaft 40 has a multi-layer structure, for example, the outer shaft 40 may have a structure in which a metal braid such as stainless steel, carbon steel, or nickel-titanium alloy is used as an intermediate layer of a resin tube that constitutes the outer shaft 40.

[0070] The shaft 10 is preferably disposed in the lumen 400 of the outer shaft 40. In the lumen 400 of the outer shaft 40, the shaft 10 is preferably disposed so as to be movable in at least one of the longitudinal direction and the circumferential direction of the shaft 10.

[0071] 3, it is more preferable that a handle 50 for allowing an operator to grasp the light irradiation medical device 1 is connected to the proximal portion of the outer shaft 40. The handle 50 may have, for example, a cylindrical shape with an inner cavity, and the outer shaft 40, the shaft 10, and the light-guiding material 20 may be inserted into the inner cavity of the handle 50.

[0072] The material of which the handle 50 is made is not particularly limited, but examples thereof include polyolefin resins such as polypropylene (PP) and polyethylene (PE), polyester resins such as polyethylene terephthalate (PET), polycarbonate resin, ABS resin, and polyurethane resin.

[0073] The outer shaft 40 is L * a * b * Chromaticity a according to the color system * It is preferable that the chromaticity a of the outer shaft 40 is in the range of 35 to 60, and the hue angle h is in the range of -45° to 45°. * It is more preferable that the outer shaft 40 has a region where the chromaticity a is 38 or more, and it is even more preferable that the outer shaft 40 has a region where the chromaticity a is 40 or more. * It is more preferable that the chromaticity of the outer shaft 40 be 58 or less, and even more preferable that the chromaticity of the outer shaft 40 be 55 or less. This configuration can easily suppress absorption of therapeutic light and also improve the visibility of the outer shaft 40. Although only a portion of the outer shaft 40 may have the above chromaticity, it is preferable that the entire outer shaft 40 have the above chromaticity.

[0074] The chromaticity of the shaft 10 and the chromaticity of the outer shaft 40 may be the same or different.

[0075] The outer shaft 40 preferably has a region where the hue angle h is equal to or greater than -45° and equal to or less than 45°. * a * b * Color space a * and b *From the value of h=tan[(b * ) / (a * ) is calculated using the formula: The hue angle h is more preferably -40° or greater, and even more preferably -30° or greater. The hue angle h is more preferably 40° or less, and even more preferably 30° or less. This configuration can more easily suppress absorption of therapeutic light and also improve the visibility of the outer shaft 40. Although only a portion of the outer shaft 40 may have the above hue angle, it is preferable that the entire outer shaft 40 have the above hue angle.

[0076] The hue angle of the shaft 10 and the hue angle of the outer shaft 40 may be the same or different.

[0077] The outer shaft 40 is lightness L * The lightness L of the outer shaft 40 is preferably 10 or more, more preferably 15 or more, and even more preferably 20 or more. * is preferably 90 or less, more preferably 85 or less, and even more preferably 80 or less. This configuration can easily suppress absorption of therapeutic light and also improve the visibility of the outer shaft 40. Although only a portion of the outer shaft 40 may have the above-mentioned brightness, it is preferable that the entire outer shaft 40 has the above-mentioned brightness.

[0078] The brightness of the shaft 10 and the brightness of the outer shaft 40 may be the same or different.

[0079] 3, the photoirradiation medical device 1 has a proximal fixing part 31 to which the proximal end of the expansion part 30 and the outer shaft 40 are fixed, and the second region 12 is preferably located on the shaft 10 distal to the position where the proximal fixing part 31 is located. The second region 12 may also be located on the shaft 10 proximal to the position where the proximal fixing part 31 is located. Although not shown, the second region may also be located only on the shaft distal to the position where the proximal fixing part is located.

[0080] Preferably, the expansion member 30 is a balloon, a basket, or a self-expanding stent.

[0081] 3, the balloon may have, in order from the proximal side, a proximal fixing portion 31 fixed to the outer shaft 40, an inflation portion 32 that is not fixed to the shaft 10 or the outer shaft 40, and a distal fixing portion 33 fixed to the shaft 10. It is preferable that the shaft 10 passes through the balloon in the longitudinal direction of the shaft 10. In this way, the balloon is joined to the shaft 10.

[0082] When the expansion section 30 is a balloon, a fluid supplier (not shown) is preferably connected to the proximal portion of at least one of the shaft 10 and the outer shaft 40. The balloon is configured so that pressurized fluid is supplied from the fluid supplier to the interior of the balloon through at least one of the shaft 10 and the outer shaft 40. When pressurized fluid is supplied to the interior of the balloon, the balloon expands, and when the pressurized fluid is withdrawn, the balloon contracts. When the balloon is expanded, the outer surface of the balloon comes into contact with the wall of a biological tract such as a blood vessel or the digestive tract, allowing the shaft 10 to be fixed inside the body.

[0083] When the expansion section 30 is a balloon, the shaft 10 may have a plurality of lumens (not shown). For example, the shaft 10 may have a first lumen which is a passage for inserting the light-guiding member 20, and a second lumen which functions as a flow path for the pressure fluid.

[0084] The inflation section 32 of the balloon may have a straight tube section 30a and tapered sections 30b formed on the distal and proximal sides of the straight tube section 30a. In this case, the shaft 10 can be fixed inside the body by bringing the outer surface of the straight tube section 30a into contact with the biological vessel wall.

[0085] The balloon is preferably made of a resin. Examples of resins that make up the balloon include polyamide resins, polyester resins, polyurethane resins, polyolefin resins, vinyl chloride resins, silicone resins, and natural rubber. These may be used alone or in combination of two or more. Among these, polyamide resins, polyester resins, and polyurethane resins are preferred. Elastomer resins can be used in terms of thinning the balloon and flexibility.

[0086] The type of fluid supplied into the balloon is not particularly limited, but may be, for example, a liquid such as physiological saline, a contrast agent, or a mixture thereof, or a gas such as air, nitrogen, carbon dioxide, etc. Among these, it is preferable to supply a gas into the balloon from the viewpoint of facilitating transmission of the emitted light.

[0087] The balloon preferably has optical transparency from the viewpoint of facilitating transmission of emitted light. The balloon preferably has the same optical transmittance as the first region 11 or a higher optical transmittance than the first region 11.

[0088] The basket is formed by bundling a plurality of elastic wires at a first bundling portion and a second bundling portion that is proximal to the first bundling portion. In the basket, the elastic wires may be bent or twisted helically between the first bundling portion and the second bundling portion. Baskets are generally used to capture foreign bodies such as stones, but in the photoirradiation medical device 1, they are used to fix the position of the photoirradiation medical device 1 inside the body.

[0089] The elastic wire is a wire material having elasticity and is preferably made of a shape memory alloy or a shape memory resin. The elastic wire may be a solid or stranded metal wire material made of, for example, stainless steel such as SUS304 or SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, aluminum, gold, silver, a Ni-Ti alloy, a Co-Cr alloy, or the like.

[0090] The number of elastic wires is not particularly limited, and can be selected depending on the inner diameter of the biological canal wall, etc.

[0091] In the first bundling section and the second bundling section, the elastic wires are preferably fixed to the shaft 10. The elastic wires can be fixed to the shaft 10 by arranging the distal or proximal ends of multiple elastic wires at intervals in the circumferential direction of the shaft 10 and brazing or gluing the distal or proximal ends of the elastic wires to the shaft 10, or by covering the distal or proximal ends of the elastic wires with a tubular connector and crimping the connector, or by other methods.

[0092] A stent is an expandable structure, e.g., a mesh or other network structure, that includes multiple struts. Stents can be formed from a pattern of interconnected structural elements that expand and contract, for example, circumferentially and axially. Stents include coiled stents made from a single linear metal or polymeric material, stents made by cutting a metal or polymeric tube with a laser or other cutting method, stents made by welding linear segments, and stents made by weaving multiple linear metal segments.

[0093] Stents can be classified into balloon-expandable and self-expandable types from the perspective of their expansion mechanism. In balloon-expandable types, the stent is mounted on the outer surface of a balloon and delivered to a treatment site such as a lesion, where the stent is expanded using a balloon. In self-expandable types, the stent is delivered to the lesion site using a catheter equipped with a member that suppresses expansion, and the member that suppresses expansion is removed at the treatment site, allowing the stent to expand on its own. Preferably, the stent is a self-expandable stent. Since a self-expandable stent does not require an internal balloon, the diameter in the contracted state can be smaller than that of a balloon-expandable stent.

[0094] For the material of the stent, reference can be made to the description of the material of the elastic wire of the basket.

[0095] When the expansion portion is a self-expanding stent, the proximal end of the self-expanding stent is preferably fixed to the distal end of the shaft, so that the light irradiation medical device can be fixed inside the body without the stent interfering with the emission of light.

[0096] If the expansion section 30 is a self-expanding stent whose distal end is more expandable than its proximal end, it is preferable that the distal end is not fixed to the distal end of the shaft 10. By bringing the distal end of the stent into contact with the wall of a biological vessel, the shaft 10 can be fixed inside the body.

[0097] The stent can be fixed to the shaft 10 in the same manner as the elastic wire of the basket is fixed to the shaft 10. At the proximal end of the stent, multiple struts can be arranged spaced apart in the circumferential direction of the shaft 10 and brazed or glued to the shaft 10, or a cylindrical connector can be placed over the proximal end of the struts and crimped.

[0098] When the expansion section 30 is a basket or a stent, it is preferable that the expansion section 30 be fixed to the shaft 10, and more preferably, the distal end and proximal end of the expansion section 30 are fixed to the shaft 10, as shown in Fig. 2. Furthermore, although not shown, it is preferable that the light irradiation medical device further has an outer shaft capable of accommodating the expansion section in its lumen. This makes it possible to prevent the basket or stent from expanding and damaging the forceps port of the endoscope, the forceps channel, or internal tissues other than foreign bodies while the light irradiation medical device is being transported from the forceps port of the endoscope through the forceps channel to near the treatment site, such as a lesion.

[0099] It is preferable that the section in the longitudinal direction of the shaft 10 where the expansion section 30 exists overlaps with the section in the longitudinal direction of the shaft 10 where the first region 11 exists. In this case, it is sufficient that the section in the longitudinal direction of the shaft 10 where the expansion section 30 exists overlaps with the section in the longitudinal direction of the shaft 10 where the first region 11 exists, but it is more preferable that they overlap entirely. A portion of the section in the longitudinal direction of the shaft 10 where the expansion section 30 exists may overlap with the entire section in the longitudinal direction of the shaft 10 where the first region 11 exists. This configuration makes it easier to fix the first region 11, which is easily permeable to light emitted from the light-guiding material 20, to the treatment site, thereby making it easier to irradiate the treatment site with therapeutic light.

[0100] 3, the expansion section 30 is a balloon, and the second region 12 is preferably present in a portion of the shaft 10 that is disposed within the lumen of the balloon. A portion of the second region 12 may be present in the portion of the shaft 10 that is disposed within the lumen of the balloon, or the entire second region 12 may be present in the portion of the shaft 10 that is disposed within the lumen of the balloon. The presence of the second region 12 makes it easier to visually confirm the location of the balloon within the body.

[0101] 3 , the light irradiation medical device 1 has a proximal fixing part 31 to which the proximal end of the expansion part 30 and the outer shaft 40 are fixed, and a distal fixing part 33 to which the distal end of the expansion part 30 and the shaft 10 are fixed, and it is preferable that a first region 11 is present between the proximal fixing part 31 and the distal fixing part 33 in the longitudinal axis direction of the shaft 10. The first region 11 may be entirely present between the proximal fixing part 31 and the distal fixing part 33, or only a part of it may be present between the proximal fixing part 31 and the distal fixing part 33. It is more preferable that the entire first region 11 is present between the proximal fixing part 31 and the distal fixing part 33, as this makes it easier to irradiate the treatment area with light while fixing the position within the body.

[0102] In the light irradiation medical device 1, it is preferable that the first section 110 of the shaft 10 shown in Figure 1, which extends from the proximal end of the first region 11 to a point 10 cm proximal to the proximal end of the first region 11, has a light transmittance of 90% or more as determined by the light transmittance measurement method described below. [Light transmittance measurement method] (1) The optical fiber diffuser connected to the light source (ML6600, Modulight) was inserted into an integrating sphere (CSTM Flux 6, Labsphere) from its distal end to 10 cm proximal to the distal end of the optical fiber diffuser. (2) Light with a wavelength of 660 nm or more and 670 nm or less is emitted from the optical fiber diffuser, and the radiant flux Ir is measured using a light intensity measuring device (FLAME-S, Ocean Photonics) connected to an integrating sphere. (3) The optical fiber diffuser is placed in the lumen 100 of the shaft 10 so that the distal end of the first section 110 coincides with the distal end of the optical fiber diffuser, and the entire shaft 10 except for the first section 110 is covered with silver foil. (4) After the step (3), the shaft 10 is inserted from the distal end of the first section 110 to the proximal end of the first section 110 into an integrating sphere. (5) Light with a wavelength of 660 nm or more and 670 nm or less is emitted from the optical fiber diffuser that has undergone steps (3) and (4), and the radiant flux Is is measured using a light intensity measuring device connected to an integrating sphere. (6) The value obtained by the formula Is / Ir is defined as the light transmittance of the first section 110.

[0103] The light transmittance measured by the above light transmittance measurement method will be referred to as a specific light transmittance hereinafter.

[0104] The wavelength of the light emitted from the optical fiber diffuser in (2) above and the wavelength of the light emitted from the optical fiber diffuser in (5) above must be the same.

[0105] When measuring the specific light transmittance in the above-mentioned light transmittance measurement method, any commercially available optical fiber diffuser can be used.

[0106] By setting the specific light transmittance as described above, it is possible to reduce the amount of therapeutic light absorbed in the first section 110 that contacts the first region 11 of the photoirradiation medical device 1. This makes it possible to suppress heat generation in the first section 110 of the photoirradiation medical device 1 and to suppress a decrease in the amount of light reaching the treatment site. [Explanation of symbols]

[0107] 1: Light irradiation medical device 10: Shaft 11:First area 12:Second area 20: Light guiding material 21: Cladding non-existence part 22: Clad 30: Extension 30a: Straight pipe section 30b: Tapered section 31: Proximal fixation part 32: Expansion section 33: Distal fixation part 40: Outer shaft 50: Handle 60: Tip 100: Shaft bore 110: First Section

Claims

1. a shaft having a distal end and a proximal end in a longitudinal direction and an inner lumen extending in the longitudinal direction; The shaft has a first region and a second region located proximal to the first region and having a lower light transmittance than the first region, and the second region has a light transmittance of L ＊ a ＊ b ＊ Chromaticity a according to the color system ＊ A light irradiation medical device in which the hue angle is 35 to 60 and the hue angle h is -45° to 45°.

2. The photoirradiation medical device according to claim 1 , wherein the length of the second region on the outer surface of the shaft in the longitudinal direction is longer than the length of the first region on the outer surface of the shaft in the longitudinal direction.

3. Further, a light guide member is provided in the inner cavity of the shaft so as to be movable in the longitudinal axis direction, and the light guide member emits light, 2. The light irradiation medical device according to claim 1, wherein the wavelength of the light emitted by the light-guiding material is 600 nm or more and 700 nm or less.

4. The light irradiation medical device of claim 1, wherein a first section of the shaft extending from the proximal end of the first region to a position 10 cm proximal to the proximal end of the first region has a light transmittance of 90% or more as determined by the light transmittance measurement method described below. [Light transmittance measurement method] (1) The optical fiber diffuser connected to a light source device (ML6600, manufactured by Modulight) is inserted into an integrating sphere (CSTM Flux 6, manufactured by Labsphere) from its distal end to a point 10 cm proximal to the distal end of the optical fiber diffuser. (2) A light quantity measuring device (Ocean Photonics, Inc.) that emits light having a wavelength of 660 nm or more and 670 nm or less from the optical fiber diffuser and is connected to the integrating sphere. The radiant flux Ir is measured by a FLAME-S. (3) The optical fiber diffuser is placed in the inner cavity of the shaft so that the distal end of the first section coincides with the distal end of the optical fiber diffuser, and the entire shaft except for the first section is covered with silver foil. (4) The shaft that has been subjected to step (3) is inserted into an integrating sphere from the distal end of the first section to the proximal end of the first section. (5) Light having a wavelength of 660 nm or more and 670 nm or less is emitted from the optical fiber diffuser that has undergone steps (3) and (4), and the radiant flux Is is measured by the light intensity measuring device connected to the integrating sphere. (6) The value obtained by the formula Is / Ir is defined as the light transmittance of the first section.

5. The photoirradiation medical device according to claim 1 , further comprising an extension portion at a distal portion of the shaft, the extension portion extending in a radial direction of the shaft.

6. the expansion portion is a balloon; The photoirradiation medical device according to claim 5 , wherein the second region is present in a portion of the shaft that is disposed in the lumen of the balloon.

7. an outer shaft having an inner lumen extending in the longitudinal direction; The photoirradiation medical device according to claim 5 , wherein the shaft is disposed in the inner cavity of the outer shaft.

8. a proximal fixing portion at which a proximal end of the expansion portion and the outer shaft are fixed; The photoirradiation medical device according to claim 7 , wherein the second region is located on the shaft distal to a position where the proximal fixing portion is located.

9. The outer shaft is L ＊ a ＊ b ＊ Chromaticity a according to the color system ＊ 8. The light irradiation medical device according to claim 7, wherein the range of hue angle is 35 to 60, and the range of hue angle is -45° to 45°.

10. The light irradiation medical device according to any one of claims 5 and 7 to 9, wherein the expansion part is a balloon, a basket, or a self-expanding stent.

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