US-20260124460-A1 - FIBER OPTIC PROBE FOR THERAPEUTIC USE

US20260124460A1US 20260124460 A1US20260124460 A1US 20260124460A1US-20260124460-A1

Abstract

The therapeutic fiber optic probe has a light transmission structure 3 capable of outputting light in a predetermined fixed direction, and a mirror structure 4 provided at a position where light output from the light transmission structure can be received, and the mirror structure reflects a portion of the received light required for treatment in a direction different from the fixed direction with a reflectance of 90% or more, and generates a light spot that exhibits a uniform light energy distribution over its entirety.

Inventors

Hideki Kanebako
Roland Bays

Assignees

Rakuten Medical, Inc.

Dates

Publication Date: 20260507
Application Date: 20260105
Priority Date: 20230710

Claims (20)

1 . A therapeutic fiber optic probe capable of generates a light spot that exhibits a uniform light energy distribution over its entirety comprising: a light transmission structure; a lens structure, wherein the lens structure is mounted at the tip of the light transmission structure and is capable of outputting transmitted light in a predetermined fixed direction; and a mirror structure, wherein the mirror structure comprises a flat reflective portion facing the lens structure, the mirror structure is provided at a position capable of receiving light output from the light transmission structure, wherein the mirror structure reflects a portion of received light in a direction different from the predetermined fixed direction with a reflectance of 90% or more; and wherein the light transmission structure, the lens and the mirror structure are comprised in a tubular structure, and wherein the tubular structure comprises an opening for passing reflected light from the mirror structure to generate the light spot.
2 . The therapeutic fiber optic probe of claim 1 , wherein the reflective portion of the mirror structure comprises a dielectric multilayer film in which dielectric thin films having high and low refractive indices are alternately stacked.
3 . The therapeutic fiber optic probe of claim 1 , wherein the reflective portion of the mirror structure is inclined at a predetermined angle θ.
4 . The therapeutic fiber optic probe of claim 3 , wherein the predetermined angle is set at 45°.
5 . The therapeutic fiber optic probe of claim 1 , further comprising a light-shielding structure on the opposite side of the mirror structure to the reflective portion.
6 . The therapeutic fiber optic probe of claim 1 , further comprising a cover, wherein the cover comprises a hollow transparent member that seals the opening of the tubular structure from the outside.
7 . The therapeutic fiber optic probe of claim 6 , wherein the cover comprises a glass material.
8 . The therapeutic fiber optic probe of claim 6 , wherein the lens and the mirror structure are enclosed in a tip of the tubular structure, and wherein the cover encloses the tip of the tubular structure.
9 . The therapeutic fiber optic probe of claim 1 , wherein the different direction is lateral or sideways as compared to the predetermined fixed direction.
10 . The therapeutic fiber optic probe of claim 2 , wherein the light received by the mirror structure includes a plurality of wavelengths that differ from each other, and wherein the mirror structure reflects wavelengths of light between 650 nm to 800 nm.
11 . The therapeutic fiber optic probe of claim 10 , wherein the mirror structure additionally reflects green light in the 530 nm wavelength.
12 . A system for treatment comprising the therapeutic fiber optic probe of claim 1 and a photoactivatable compound.
13 . A method of treating a subject with a photoactivatable compound and a therapeutic fiber optic probe, wherein the therapeutic fiber optic probe comprises: a light transmission structure; a lens structure, wherein the lens structure is mounted at the tip of the light transmission structure and is capable of outputting transmitted light in a predetermined fixed direction; and a mirror structure, wherein the mirror structure comprises a flat reflective portion facing the lens structure, the mirror structure is provided at a position capable of receiving light output from the light transmission structure, wherein the mirror structure reflects a portion of received light in a direction different from the fixed direction with a reflectance of 90% or more; and wherein the light transmission structure, the lens and the mirror structure are comprised in a tubular structure, and wherein the tubular structure comprises an opening for passing reflected light from the mirror structure to generate the light spot.
14 . The method of claim 13 , wherein the photoactivatable compound is a phthalocyanine dye or a conjugate of the phthalocyanine dye, and wherein the photoactivatable compound is administered to a subject prior to administration of light with the therapeutic fiber optic probe.
15 . The method of claim 14 , wherein the photoactivatable compound comprises a conjugate of IRDye700DX and a targeting agent.
16 . The method of claim 15 , wherein the subject is treated for a cancer.
17 . The method of claim 15 , wherein the subject is treated for esophageal cancer, uterus cancer, vaginal cancer, colorectal cancer or endometriosis.
18 . A method of producing a light spot of one or more specific wavelengths on a target surface, wherein the method comprises: transmitting light by a therapeutic fiber optic probe, wherein the therapeutic fiber optic probe comprises: a light transmission structure; a lens structure, wherein the lens structure is mounted at the tip of the light transmission structure and is capable of outputting transmitted light in a predetermined fixed direction; and a mirror structure, wherein the mirror structure comprises a flat reflective portion facing the lens structure, the mirror structure is provided at a position capable of receiving light output from the light transmission structure, wherein the mirror structure reflects a portion of received light in a direction different from the predetermined fixed direction with a reflectance of 90% or more; and wherein the reflective portion of the mirror structure comprises a dielectric multilayer film in which dielectric thin films having high and low refractive indices are alternately stacked; wherein the light transmission structure, the lens and the mirror structure are comprised in a tubular structure, and wherein the tubular structure comprises an opening for passing reflected light from the mirror structure to generate the light spot, whereby the light spot exhibits a uniform light energy distribution over its entirety.
19 . The method of claim 18 , wherein the mirror structure reflects a first wavelength of light between 650 nm to 800 nm.
20 . The method of claim 19 , wherein the mirror structure additionally reflects a second wavelength of 530 nm, and wherein the light spot generated by the first wavelength and the second wavelength have the same size and shape as each other on the target surface.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation Application of PCT Application No. PCT/US2024/037111, filed Jul. 9, 2024 and based upon and claiming the benefit of priority from prior Japanese Patent Application No. 2023-112807, filed Jul. 10, 2023, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber optic probe for therapeutic use. 2. Description of the Related Art Currently, there is a treatment method that consists of two steps: administering to a patient a drug containing a conjugate composed of a light-sensitive dye and a component that targets the dye to specific cells, and irradiating the patient with light of a specific wavelength to which the light-sensitive dye reacts. The light-sensitive dye reacts with light in a specific wavelength range. The drug (conjugate) is administered and allowed to selectively target to the specific cells, and then those cells are irradiated with light of a specific wavelength for a certain period of time, activating the light-sensitive dye and causing the specific cells to die or be eliminated through biochemical and physical processes. In delivering the light irradiation to specific tissues, fiber optic probes are used for treatment. For example, phototherapy in which light (including laser light) is irradiated from the surface to affected areas outside the body, or phototherapy in which light (including laser light) is irradiated from the surface to affected areas inside the body, etc. is being performed. Fiber optic probes used for the above-described phototherapy, are generally forward (front) irradiation type probes (i.e., existing frontal diffusers) that irradiate light from their tips toward the front are used. In this case, in a frontal diffuser, the direction of light irradiation is limited to only forward (front) from its tip. Therefore, in phototherapy, it is necessary to orient or bend the frontal diffuser so that the tip of the diffuser is directly facing an affected area. However, the frontal diffuser has a set permissible curvature (bending) radius, and there are certain limitations on the curvature direction and amount. In addition, an irradiation distance from the tip of the frontal diffuser to the irradiated surface must also be kept above a certain distance. Therefore, for example, in a narrow lumen, there may be an area where it is difficult to irradiate light, and in a case where there is an affected part in that area, it may be difficult to smoothly deliver light to perform phototherapy or photoimmunotherapy on that affected part. To solve this problem, the tip should be configured to irradiate light in a direction other than forward (front), for example, in a sideward (lateral) direction. However, if a typical mirror is used to reflect the light, the reflectance is low. For example, the JIS standard for mirror materials (JIS R 3220:2011) specifies that the reflectance of a mirror should be 83% or higher. In addition, since light-sensitive dyes must be irradiated with a certain amount of light energy in order to be activated by light of a specific wavelength, the light energy must be uniformly irradiated to the irradiated surface. Furthermore, fiber optic probes are also assumed to be used together with endoscopes and catheters. Therefore, the size (diameter) of the fiber optic probe, including the tip, is required to be set to a dimension that allows it to be inserted into an endoscope or catheter. BRIEF SUMMARY OF THE INVENTION One of the purposes of the present invention is to provide a therapeutic fiber optic probe with a tip that is set to dimensions that allow insertion into an endoscope or catheter and that can efficiently irradiate uniform light in a sideward (lateral) direction. To achieve such a purpose, a therapeutic fiber optic probe according to embodiments comprises a light transmission structure capable of outputting light in a predetermined fixed direction and a mirror structure provided at a position capable of receiving light output from the light transmission structure, in which the mirror structure reflects a portion of received light required for treatment in a direction different from the fixed direction with a reflectance of 90% or more, and generates a light spot that exhibits a uniform light energy distribution over its entirety. According to the above structure, it is possible to realize a therapeutic fiber optic probe with a tip that is set to dimensions that allow insertion into an endoscope or catheter and that can efficiently irradiate uniform light in a sideward (lateral) direction. Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentaliti