Endoscope system, method for operating endoscope system, and method for controlling endoscope system

Abstract

Provided is an endoscope system 1 that appropriately irradiates a target site with light. The endoscope system 1 comprises: an optical probe 30 for guiding light from a therapeutic light source 20 and spot-irradiating a target site 90 with the light; an endoscope 10 having an opening from which the optical probe 30 protrudes and a camera 14 that acquires an image signal at a distal end portion 11A; and a processor 40 for generating an endoscopic image. The optical probe 30 has a mark 32 on the outer peripheral surface at a predetermined distance from the distal end. The processor 40 generates a first targeting image M1 aligned with the mark 32 and a second targeting image M2 to be aligned with a spot S of the light at the target site 90, and displays the first targeting image M1 and the second targeting image M2 superimposed on the endoscopic image.

Description

Endoscope system, method of operating an endoscope system, and method of operating an endoscope system

[0001] The present invention relates to an endoscope system that irradiates a target site with light, a method of operating an endoscope system that irradiates a target site with light, and a method of operating an endoscope system that irradiates a target site with light.

[0002] In photoimmunotherapy (PIT), cancer is treated by specifically binding an antibody drug to cancer cells, then activating the antibody drug by irradiation with therapeutic light to destroy the cancer cells.

[0003] In photoimmunotherapy, it is necessary to irradiate an appropriate range with therapeutic light of an appropriate light intensity. However, when irradiation is performed using an endoscope inserted into the body, it is not easy to determine the irradiation range (size of the light spot) of therapeutic light on a target site from an endoscopic image. A similar problem also exists in photodynamic therapy (PDT), which necrosis tumor tissue by irradiating a photosensitizing substance accumulated in tumor tissue with laser.

[0004] International Publication No. WO 2020 / 176124 discloses a method for estimating the size of a lesion area using the known diameter of the tip of a rod protruding from the distal end portion of an endoscope, which is captured in an endoscopic image.

[0005] However, in the above method, the size of the lesion area cannot be estimated unless the tip of the rod is brought into contact with the lesion area.

[0006] Japanese Unexamined Patent Publication No. 2023-127544 discloses a phototherapeutic device that provides two irradiation periods for irradiating light with appropriate energy in photoimmunotherapy.

[0007] International Publication No. 2020 / 176124 Japanese Unexamined Patent Publication No. 2023-127544

[0008] An object of an embodiment of the present invention is to provide an endoscope system that appropriately irradiates a target site with light, a method of operating an endoscope system that appropriately irradiates a target site with light, and a method of operating an endoscope system that appropriately irradiates a target site with light.

[0009] An endoscope system according to an embodiment of the present invention comprises a light source, an optical probe having an illumination optical system at its tip that guides light from the light source and spot-irradiates the light onto a target area, a camera that acquires an image signal, an endoscope having an aperture at its tip from which the optical probe protrudes, and a processor that generates an endoscope image from the image signal, wherein the optical probe has a mark on its outer surface at a predetermined distance from its tip, and the processor generates a first targeting image aligned with the mark and a second targeting image aligned with the spot of light on the target area, and displays the first targeting image and the second targeting image superimposed on the endoscope image.

[0010] The operation method of the endoscope system according to an embodiment of the present invention involves an optical probe having an illumination optical system at its tip that spot-irradiates light onto a target area, generating an endoscope image from an image signal acquired by an endoscope protruding from its tip, generating a first targeting image aligned with a mark on the outer surface of the optical probe at a predetermined distance from its tip, and a second targeting image aligned with the spot of light on the target area, and displaying the first and second targeting images superimposed on the endoscope image.

[0011] The operation method of the endoscope system according to an embodiment of the present invention involves extending an optical probe, which has an illumination optical system at its tip for spot-illuminating a target area with light, from the tip of the endoscope; aligning a first targeting image, which is superimposed on the endoscope image generated from the image signal acquired by the endoscope, with a mark on the outer surface of the optical probe at a predetermined distance from the tip; and aligning a second targeting image, which is superimposed on the endoscope image, with the spot of light at the target area.

[0012] According to embodiments of the present invention, it is possible to provide an endoscope system that appropriately irradiates a target area with light, a method for operating the endoscope system that appropriately irradiates a target area with light, and a method for operating the endoscope system that appropriately irradiates a target area with light.

[0013] Figure 1 is a perspective view of the endoscope system of the embodiment. Figure 2 is a perspective view of the tip of the endoscope of the endoscope system of the first embodiment. Figure 3 is an endoscopic image of the endoscope system. Figure 4 is an endoscopic image of the endoscope system of the first embodiment. Figure 5 is an endoscopic image of the endoscope system of the first embodiment. Figure 6 is a flowchart of the method for generating the targeting image of the endoscope system of the first embodiment. Figure 7 is a plan view illustrating the second targeting image of the endoscope system of the first embodiment. Figure 8 is a perspective view illustrating the second targeting image of the endoscope system of the first embodiment. Figure 9 is a perspective view illustrating the first targeting image of the endoscope system of the first embodiment. Figure 10 is a plan view illustrating the first targeting image of the endoscope system of the first embodiment. Figure 11 is an endoscopic image illustrating the alignment state of the first targeting image of the endoscope system of the first embodiment. Figure 12 is a cross-sectional view perpendicular to the longitudinal direction of the lumen illustrating the state of the optical probe of the endoscope system of the first embodiment. Figure 13 is an endoscopic image of an endoscope system of a modified example of the first embodiment. Figure 14 is a perspective view illustrating the endoscope system of the second embodiment. Figure 15 is an endoscopic image of the endoscope system of the second embodiment.

[0014] <First Embodiment> As shown in Figure 1, the endoscope system 1 of the embodiment comprises an endoscope 10, a therapeutic light source 20, an optical probe 30, a processor 40, a monitor 50, and an illumination light source 60.

[0015] In the following description, the drawings based on the embodiments are schematic. The relationship between the thickness and width of each part, the ratio of the thicknesses of each part, and the relative angles differ from those of reality. There are also parts where the dimensional relationships and ratios differ between drawings. The illustration and reference numerals of some components are omitted.

[0016] Endoscopic system 1 is used, for example, for light irradiation of the affected area (target site) in photoimmunotherapy. After administering the antibody drug intravenously to the patient via infusion, light irradiation of the target site by endoscopy system 1 is performed 20 to 28 hours prior to the administration of the antibody drug intravenously.

[0017] The endoscope 10 has an insertion section 11 that is inserted into the patient's body. An operating section 12, equipped with various buttons for operating the endoscope 10, is located at the base end of the insertion section 11. The insertion section 11 consists of a tip section 11A where a camera 14 is located, a bending section 11B connected to the base end of the tip section 11A, and a flexible section 11C connected to the base end of the bending section 11B. The bending section 11B bends when operated by the operating section 12.

[0018] A universal cord 13 extending from the control unit 12 is connected to the processor 40 and the illumination light source 60 by a connector 13A. A memory 19 storing model data of the endoscope 10 is located on the connector 13A.

[0019] The therapeutic light source 20 generates therapeutic light that reacts with the drug used in photoimmunotherapy, and guide light that does not react with the drug. For example, the therapeutic light source 20 has two lasers, one for therapeutic light and one for guide light. The therapeutic light source 20 may also have a white light source that includes near-infrared light, which is the therapeutic light, and an optical filter that cuts out the near-infrared light from the white light.

[0020] The user sets the size of the light spot, as described later, using the setting unit 21 of the therapeutic light source 20. Alternatively, the processor 40 may have the setting unit instead of the therapeutic light source 20.

[0021] The illumination light generated by the illumination light source 60 is emitted from the illumination window 61 (see Figure 2) at the tip 11A via an optical fiber (not shown) inserted through the insertion section 11. The camera 14 receives the reflected illumination light and outputs an imaging signal. Preferably, the illumination light has the wavelength range of the therapeutic light cut off.

[0022] The optical probe 30 is inserted through the insertion port 12A of the operating section 12, passes through the insertion section 11, and protrudes from the opening H11A of the tip surface 11SA of the tip section 11A (Figure 2). The optical probe 30 guides the guide light and the treatment light generated by the treatment light source 20. That is, the optical probe 30 guides the guide light when aligning the irradiation position of the light spot, as described later, and guides the treatment light during treatment after alignment. The optical probe 30 may also guide the guide light together with the treatment light and irradiate the target area 90 during treatment.

[0023] The processor 40 controls the entire endoscope system 1 and performs signal processing on the imaging signal output by the camera 14, outputting it as an image signal. The processor 40 may consist of an internal circuit (CPU) of a semiconductor element that processes data via software, or a dedicated hardware circuit, or it may include both an internal circuit of a semiconductor element and a dedicated hardware circuit.

[0024] The monitor 50 is a liquid crystal display or the like that displays the image signals output by the processor 40 as endoscopic images.

[0025] Although the endoscope 10 is a flexible endoscope, the endoscope in another embodiment may be a rigid endoscope.

[0026] As shown in Figure 2, the optical probe 30 protrudes from the opening H11A of the tip surface 11SA of the tip portion 11A. The optical probe 30 has a diffuser 35, which is an illumination optical system, at its tip. The diffuser 35 diffuses the light to spot-irradiate the target area 90 with light. A substantially circular spot of light S is irradiated onto the surface of the target area 90.

[0027] In this embodiment, the optical probe 30 is a so-called side-illumination type, which irradiates light onto the target area 90 in a lateral direction perpendicular to the long axis C30. That is, the direction of light irradiation is perpendicular to the direction of the optical axis O of the camera 14.

[0028] The optical probe 30 has a mark 32 on its outer surface at a predetermined distance from its tip. The mark 32 is linear and encircles the outer surface. The emitter 35A of the diffuser 35 of the optical probe 30 is located at a known distance from the tip of the optical probe 30. That is, the mark 32 is provided at a predetermined distance from the emitter 35A of the diffuser 35. If the optical probe 30 has, for example, linear irregularities encircling its outer surface, these linear irregularities may be considered as the mark 32. The illumination optical system may also be configured to diffuse light using a lens instead of the diffuser 35.

[0029] The camera 14 includes an imaging optical system 14A containing multiple lenses, and an image sensor 14B that receives the subject image focused by the imaging optical system 14A. The lens center P14 at the outermost surface (tip surface 11SA) of the imaging optical system 14A can be considered as the viewpoint of the camera 14.

[0030] Figure 3 shows an endoscopic image of the endoscope 10 inserted into a lumen, as displayed on the monitor 50. The viewpoint of the endoscopic image is the lens center P14, and the center of the image is the extension of the optical axis O of the camera 14 (imaging optical system 14A). The light is diffused in a circular shape by the diffuser 35, but the spot S of light irradiated onto the target area 90 (e.g., cancerous tissue) on the wall surface of the cylindrical lumen is displayed as an approximately elliptical shape in the endoscopic image.

[0031] It is not easy to estimate the size (area) of spot S and the light intensity at the target site 90 from the endoscopic image shown in Figure 3.

[0032] Endoscope system 1 assists the user in irradiating the target area with appropriate light.

[0033] The processor 40 of the endoscope system 1 generates a first targeting image M1 that is aligned with the mark 32, and a second targeting image M2 that is aligned with the light spot S in the target area 90. Then, as shown in Figure 4, the processor 40 superimposes the first targeting image M1 and the second targeting image M2 onto the endoscope image displayed on the monitor 50.

[0034] The first targeting image M1 is a roughly straight line parallel to the longitudinal direction of the image of the optical probe 30 in the endoscopic image. The illustrated second targeting image M2 is roughly ring-shaped, but it may also be a shape in which a part of the ring superimposed on the image of the optical probe 30 is omitted.

[0035] As shown in Figure 5, when the first targeting image M1 and the mark 32 are aligned, and the second targeting image M2 and the spot S are aligned, the size of the spot S becomes a predetermined value set by the setting unit 21. Therefore, the endoscope system 1 can appropriately irradiate the target area 90 with light.

[0036] <Operation Method> The operation method of the endoscope system 1 will be explained using the flowchart in Figure 6. Until the positioning (size adjustment) of the spot S is completed, the treatment light source 20 outputs guide light from which the near-infrared light, which is the treatment light, has been cut off.

[0037] When the endoscope 10 is connected to the processor 40, the processor 40 reads the model data of the endoscope 10 stored in the memory 19. For example, if the processor 40 has model data corresponding to the model number of the endoscope 10 stored in it, simply by connecting the endoscope 10 to the processor 40, the model can be recognized and detailed model data can be input into the processor 40. The model data can also be entered numerically by the user into the processor 40. The specifications of the optical probe 30 can also be stored in the memory (not shown) of the optical probe 30, or the user can enter numerically.

[0038] <Step S10> The target spot size (φS) is set using the setting unit 21. Once the spot size is set, the treatment light source 20 sets the irradiation intensity of the treatment light on the surface of the target area 90 according to the treatment conditions (type of antibody drug, etc.).

[0039] <Step S20> The irradiation distance LS (distance LS) at which the spot size (φS) becomes the target size is calculated by the processor 40 using the specifications of the optical probe 30 (beam size at the emission section 35A, diffusion angle θ).

[0040] That is, as shown in FIG. 7, the light emitted from the emission portion 35A of the diffuser 35 spreads circularly at a diffusion angle θ. The size of the spot S (outer diameter φS) is determined by the distance from the emission portion 35A (≒ the distance LS from the central axis C of the optical probe 30). Of course, the processor 40 may calculate the irradiation distance LS based on the diffusion angle θ, the beam size at the emission portion 35A, and the length from the central axis C of the optical probe 30 to the emission portion 35A.

[0041] As shown in FIG. 8, on the circumference of a virtual circle m2 where the distance LS from the central axis C of the optical probe 30 is the same, the size of the spot S remains the same even when the optical probe 30 is rotated. That is, when the size of the spot S is specified, the distance LS (the virtual circle m2) is uniquely determined. A second aiming image M2 in an endoscopic image is created based on the size of the virtual circle m2 in real space (XYZ space).

[0042] As shown in FIG. 9, when the protrusion length L30 of the optical probe 30 from the distal end surface 11SA is set, the length L35 from the distal end surface 11SA to the emission portion 35A is determined. The length L35 is regarded as a working distance which is the distance between the lens center P14 and a plane passing through the emission portion 35A and parallel to the distal end surface 11SA.

[0043] As shown in FIG. 10, the positional relationship between the optical axis O of the camera 14 on the distal end surface 11SA and the central axis C of the optical probe 30 (the center of the opening H11A) is known from the specifications of the endoscope. That is, when expressed in XY coordinates centered on the optical axis O on the distal end surface 11SA, the central axis C is located at (ΔX, ΔY).

[0044] <Step S30> As described above, in real space (XYZ space) centered on the lens center P14, the center coordinates (X, Y, Z) of the virtual circle m2 are (ΔX, ΔY, WD).

[0045] <Step S40> Based on the model data of the endoscope 10, a second aiming image M2 is calculated by the processor 40. The model data of the endoscope 10 are, for example, specifications of the camera 14 (the size of the image sensor 14B, the imaging optical system 14A, the imaging magnification, aberration parameter values, etc.). Based on the model data of the endoscope 10, the processor 40 calculates the position and size of a virtual circle m2 in an endoscopic image which is a two-dimensional image from the lens center P14 serving as a viewpoint, that is, the second aiming image M2. Then, the processor 40 superimposes the second aiming image M2 on the endoscopic image.

[0046] In addition, the position of the mark M of the optical probe 30 with a predetermined protrusion length L30 in the endoscopic image is calculated by the processor 40. The processor 40 superimposes a first aiming image M1 on a position of the endoscopic image where the mark M of the optical probe 30 with the predetermined protrusion length L30 is to be superimposed. Note that the setting of the protrusion length L30 may be adjustable using the processor 40.

[0047] It should be noted that the first aiming image M1 shown in FIG. 5 and the like is a short straight line parallel to the long axis direction of the optical probe 30 in the endoscopic image. As long as it can be aligned with the mark 32 of the optical probe 30, the first aiming image M1 may be a curve similar to the mark 32 in the endoscopic image, a small circle, or a shape that allows the mark 32 to fit between two parallel curves.

[0048] In addition, although the second aiming image M2 is ring-shaped, it may be a substantially ring shape with a part of the ring removed, or a double ring.

[0049] In the alignment of the spot S, the first aiming image M1 and the mark are aligned first. Next, the spot S is aligned with the second aiming image M2. After the alignment is completed, therapeutic light is emitted from the therapeutic light source 20 for a predetermined period of time to perform treatment.

[0050] Figure 11 shows multiple states of a spot in an endoscopic image. Spot S1 is located inside the second aiming image M2, so it can be inferred that the irradiation distance LS is shorter than the target. Spot S2 is located outside the second aiming image M2, so it can be inferred that the irradiation distance LS is longer than the target. Spot S3 is located on the second aiming image M2, and the irradiation distance LS coincides with the target.

[0051] Furthermore, the long axis of spot S4 is inclined with respect to the circumferential direction of the second targeting image M2. This is because, as shown in Figure 12, the optical probe 30 is irradiating obliquely in a direction perpendicular to the longitudinal direction of the cylindrical lumen. Spot S4 is undesirable because the light intensity distribution within the spot is large. In other words, it is preferable that the substantially elliptical spot S be positioned such that its long axis touches the circumference of the second targeting image M2 at two points, or in other words, is tangent to it.

[0052] <Modified Version of the First Embodiment> The endoscope system 1A of this modified version is similar to the endoscope system 1. Therefore, the same reference numerals are used for components with the same functions as the endoscope system 1, and their descriptions are omitted.

[0053] The endoscope system 1A allows for the setting of multiple protrusion lengths L30, and displays multiple first targeting images M1 and multiple second targeting images M2 corresponding to the multiple protrusion lengths L30.

[0054] For example, as shown in Figure 13, a first aiming image M1A and a second aiming image M2A corresponding to a protrusion length of 35 mm, and a first aiming image M1B and a second aiming image M2B corresponding to a protrusion length of 25 mm are displayed.

[0055] <Second Embodiment> The endoscope system 1B of the second embodiment is similar to the endoscope system 1. Therefore, the same reference numerals are used for components with the same functions as the endoscope system 1, and their descriptions are omitted.

[0056] As shown in Figure 14, the optical probe 30B of the endoscope system 1B is a so-called frontal irradiation type that irradiates light in the longitudinal direction. That is, the direction of light irradiation is parallel to the direction of the optical axis O of the camera 14.

[0057] As shown in Figure 15, in the endoscope system 1B, a roughly circular spot S is aligned with a second targeting image M2 of the same size, allowing light to be appropriately irradiated onto the target area 90. In Figure 15, the first targeting image M1, which is aligned with the mark M, is a straight line perpendicular to the long axis of the optical probe 30.

[0058] Furthermore, it goes without saying that even if the endoscope is of the so-called oblique type and the optical probe 30 protrudes from the side of the tip 11A, if it has the same configuration as the endoscope system 1B, it will have the same effect as the endoscope system 1B.

[0059] The present invention is not limited to the embodiments described above, and various changes and modifications can be made without altering the essence of the invention.

[0060] 1, 1A, 1B... Endoscope system 10... Endoscope 11... Insertion section 11A... Tip section 11B... Bending section 11C... Flexible section 11SA... Tip surface 12... Control section 12A... Insertion socket 13... Universal cord 13A... Connector 14... Camera 14A... Imaging optics 14B... Image sensor 19... Memory 20... Therapeutic light source 21... Setting section 30, 30A... Optical probe 32... Mark 35... Diffuser (Irradiation optics) 35A... Output section 40... Processor 50... Monitor 60... Illumination light source 61... Illumination window 90... Target area

Claims

1. An endoscope system comprising: a light source; an optical probe having an illumination optical system at its tip that guides light from the light source and spot-irradiates the light onto a target area; a camera that acquires an image signal; an endoscope having an aperture at its tip from which the optical probe protrudes; and a processor that generates an endoscope image from the image signal, wherein the optical probe has a mark on its outer surface at a predetermined distance from its tip; the processor generates a first targeting image aligned with the mark and a second targeting image aligned with the spot of light on the target area, and displays the first targeting image and the second targeting image superimposed on the endoscope image.

2. The endoscope system according to claim 1, characterized in that the second targeting image is substantially ring-shaped, and in the endoscope image, when the first targeting image and the mark are aligned and the second targeting image and the spot are aligned, the size of the spot in the target area becomes a predetermined value.

3. The endoscopic system according to claim 2, characterized in that the direction of the light irradiation is perpendicular to the optical axis direction of the camera, the mark and the first targeting image are aligned, and the major axis direction of the substantially elliptical spot is aligned on the circumference of the second targeting image.

4. The endoscopic system according to claim 2, characterized in that the direction of illumination of the light is parallel to the optical axis direction of the camera, the mark and the first targeting image are aligned, and the substantially circular spot is aligned with the second targeting image.

5. The endoscopic system according to claim 1, characterized in that the light is a guide light that does not react to drugs used in photoimmunotherapy.

6. The endoscopic system according to claim 5, characterized in that the light source is capable of generating therapeutic light in which the drug reacts.

7. The endoscope system according to claim 1, characterized in that the processor calculates the first targeting image and the second targeting image using model data of the endoscope, including the imaging magnification and aberration parameter values ​​of the imaging optical system of the camera.

8. The endoscope system according to claim 5, wherein the endoscope has a memory for storing model data, and the processor reads the model data from the memory.

9. The endoscope system according to claim 1, wherein the light source or the processor has a setting unit for setting the size of the spot, and the processor generates the second aiming image based on the size of the spot.

10. The endoscope system according to claim 9, characterized in that the light source adjusts the light intensity based on the size of the spot set in the setting unit.

11. An operation method for an endoscope system, characterized in that an optical probe having an illumination optical system at its tip for spot-illuminating a target area generates an endoscope image from an image signal acquired by an endoscope protruding from its tip, generates a first targeting image aligned with a mark on the outer surface of the optical probe at a predetermined distance from its tip, and a second targeting image aligned with the spot of light at the target area, and displays the first targeting image and the second targeting image superimposed on the endoscope image.

12. An operation method for an endoscope system, characterized by: extending an optical probe having an illumination optical system at its tip for spot-illuminating a target area with light from the tip of an endoscope; aligning a first targeting image superimposed on an endoscope image generated from an image signal acquired by the endoscope with a mark on the outer surface of the optical probe at a predetermined distance from the tip; and aligning a second targeting image superimposed on the endoscope image with the spot of light at the target area.

Images