JPWO2019215906A1 - Medical image imaging device - Google Patents

Abstract

This medical image imaging device (1) is located in at least the wavelength region of the light (FL) emitted by the indoor illumination among the fluorescence (IR) emitted from the photosensitive substance (Pa) by irradiating the treatment light (EL). A detector filter (12) that transmits light having a predetermined wavelength that is the wavelength of the second emission peak (41b) that is not included, a detector (9) that detects fluorescence transmitted through the detector filter, and a detector. It includes an image generation unit (14) that generates a fluorescence image (16a) based on the output.

Description

The present invention relates to a medical image imaging device, and more particularly to a medical image imaging device that captures an image at the time of treatment and provides treatment support.

Conventionally, a medical image imaging device that captures an image at the time of treatment and provides treatment support is known. Such a medical image imaging device is disclosed in, for example, Japanese Patent Application Laid-Open No. 2012-023492.

In Japanese Patent Application Laid-Open No. 2012-023492, a subject containing a light-sensitive substance is irradiated with visible light and excitation light, and a visible light image of the subject and a fluorescence image generated from the light-sensitive substance by the excitation light are obtained. A medical image imaging device that provides treatment support is disclosed. Japanese Patent Application Laid-Open No. 2012-023492 discloses a configuration in which a surgical site to which a photosensitive substance is administered is irradiated with visible light and excitation light by switching each other to obtain a visible light image and a fluorescent image. ing. The photosensitive substance is a drug that emits fluorescence having a predetermined wavelength when irradiated with excitation light having a predetermined wavelength. In JP2012-023492, indocyanine green (hereinafter referred to as ICG) is used as a light-sensitive substance. Japanese Patent Application Laid-Open No. 2012-023492 provides treatment support by administering ICG to a subject and visualizing the site to be excised by irradiating the subject with excitation light.

In addition to the purpose of visualizing the site to be excised, it is known to use a light-sensitive substance. A method of using such a photosensitive substance is disclosed in, for example, Japanese Patent Application Laid-Open No. 2017-071654. In Japanese Patent Application Laid-Open No. 2017-071654, a drug in which a substance that fluoresces by absorbing excitation light and an antibody that selectively binds to cancer cells is bound is administered to a subject and irradiated with excitation light. A method of killing cancer cells by doing so is disclosed. In Japanese Patent Application Laid-Open No. 2017-071654, IRDye (registered trademark) 700Dx (hereinafter referred to as IR700) is used as a photosensitive substance.

There are cases where it is desired to confirm the therapeutic effect of cancer by the method disclosed in JP-A-2017-071654. For example, depending on the size of the cancer cells after irradiation with the treatment light, it may be desired to confirm the size of the cancer cells in order to determine whether or not it is necessary to irradiate the treatment light again. The size of cancer cells can be confirmed by the fluorescence image generated based on the fluorescence emitted by the photosensitive substance irradiated with the excitation light. However, the wavelength band of the excitation light to be irradiated differs depending on the light-sensitive substance. In addition, since the wavelength band of fluorescence emitted by irradiation with excitation light also differs depending on the light-sensitive substance, the wavelength band of fluorescence emitted from the light-sensitive substance is that of light such as indoor lighting used in an operating room or the like. It may overlap with the wavelength region. In the present specification, the indoor lighting includes fluorescent lamps, white light bulbs, LED lighting, emergency lights, monitors, lights lit by medical devices, and the like.

Since the ICG used in the medical image imaging apparatus of JP2012-023492 has a fluorescence wavelength longer than the wavelength region of the light of the room illumination, the influence of the room illumination on the fluorescence image is small. However, when IR700 disclosed in Japanese Patent Application Laid-Open No. 2017-071654 is used as the light-sensitive substance, the fluorescence wavelength region emitted from the IR700 includes light close to the wavelength region of the light of indoor lighting, and therefore the IR700. When an image is generated based on the fluorescence emitted from the light, light from indoor lighting or the like is reflected in the fluorescence image. When light from indoor lighting or the like is reflected in a fluorescent image, the background (light other than fluorescence emitted by a photosensitive substance) rises, so when a fluorescent image is generated using a high-resolution image sensor, noise increases. .. Further, when the IR700 is excited by using the excitation light, the excitation light is reflected in the fluorescence image because the wavelength of the excitation light of the IR700 and the wavelength of the fluorescence are close to each other. Further, since the wavelength of the excitation light of the IR700 is close to the wavelength region of the near infrared ray, the surgical field is illuminated in red when the excitation light close to the wavelength region of the near infrared ray is irradiated.

As described above, when an image is generated based on the fluorescence emitted from a light-sensitive substance, there is a problem that the light of indoor lighting or the like is reflected in the fluorescence image and the image quality of the fluorescence image is deteriorated.

Japanese Unexamined Patent Publication No. 2012-023492 Japanese Unexamined Patent Publication No. 2017-071654

The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to generate a fluorescence image based on the fluorescence emitted by a light-sensitive substance injected into a subject. It is an object of the present invention to provide a medical image imaging device capable of suppressing deterioration of the image quality of a fluorescent image due to superimposition of light other than fluorescence emitted by a light-sensitive substance such as indoor lighting on the fluorescent image.

In order to achieve the above object, the medical image imaging apparatus according to the first aspect of the present invention irradiates a light-sensitive substance accumulated in a treatment target site in a subject with therapeutic light to perform the treatment target site at the time of treatment. It is a medical image imaging device that images and generates an image, and is a detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from a photosensitive substance by irradiating with therapeutic light, and a detector filter. It is provided with a detector that detects the fluorescence transmitted through the light and an image generation unit that generates an image based on the output of the detector. The fluorescence has at least a first emission peak and a second emission peak, and the first emission peak. The wavelength of the second emission peak is a wavelength equal to or less than the wavelength of the second emission peak and is included in the wavelength region of the light emitted by the indoor illumination, and the wavelength of the second emission peak is included in the wavelength region of the light emitted by the indoor illumination. There is no wavelength, and the predetermined wavelength is the wavelength of the second emission peak.

As described above, the medical image imaging apparatus according to one aspect of the present invention transmits light having a predetermined wavelength that is not included in the wavelength region of the light emitted by the indoor lighting among the fluorescence emitted from the photosensitive substance. It is equipped with a detector filter. As a result, the detector filter can remove the light in the wavelength region of the light emitted by the room lighting. That is, among the fluorescence from the light-sensitive substance, the light contained in the wavelength region of the indoor illumination light is intentionally removed together with the indoor illumination light, and an image is generated by the fluorescence having a wavelength longer than the wavelength region of the indoor illumination light. Can be done. Therefore, it is possible to suppress an increase in the background when a fluorescent image is generated based on the fluorescence emitted by the photosensitive substance injected into the subject. In addition, since it is possible to suppress an increase in the background, it is possible to suppress an increase in noise even when a fluorescent image is generated using a high-resolution image sensor. As a result, when a fluorescent image is generated based on the fluorescence emitted by the photosensitive substance injected into the subject, the light of the room illumination is superimposed on the fluorescent image, and the deterioration of the image quality of the fluorescent image is suppressed. Can be done.

In the medical image imaging apparatus in the first aspect, preferably, the detector filter is configured to transmit light having a wavelength longer than the wavelength of the first emission peak, including a predetermined wavelength. With this configuration, for example, when the wavelength of the first emission peak of fluorescence emitted by a photosensitive substance is included in the wavelength region of the light of the indoor illumination, the indoor illumination included in the wavelength region less than the wavelength of the first emission peak. The light emitted by the detector can be removed by the detector filter. As a result, it is possible to suppress the reflection of the light of the indoor illumination in the wavelength region of the first emission peak on the fluorescence image.

In the medical image imaging apparatus according to the first aspect, preferably, the detector filter is configured to transmit light having a wavelength longer than the upper limit wavelength of the wavelength region of the light emitted by the indoor lighting, including a predetermined wavelength. There is. With this configuration, among the fluorescence emitted by the photosensitive substance, the fluorescence having a wavelength longer than the upper limit wavelength of the wavelength region of the light emitted by the indoor lighting can be detected. As a result, it is possible to further suppress the superimposition of the light of the room lighting on the fluorescent image when generating the fluorescent image, so that it is possible to further suppress the deterioration of the image quality of the fluorescent image. ..

In the medical image imaging apparatus in the first aspect, the intensity of the first emission peak is preferably higher than the intensity of the second emission peak. If such a light-sensitive substance that emits fluorescence is used, for example, even if the wavelength of the first emission peak is included in the wavelength region of the light emitted by the room illumination, the fluorescence of the wavelength of the first emission peak is illuminated indoors. It can be intentionally removed together with the light of the above, and an image can be generated by the fluorescence of the second emission peak. As a result, by removing the light contained in the wavelength region of the light of the indoor lighting, it is possible to improve the S / N ratio of the light of the second emission peak whose intensity is lower than the intensity of the first emission peak. Even if the fluorescence of the second emission peak is used, it is possible to suppress the deterioration of the image quality of the fluorescent image.

In the medical image imaging apparatus in the first aspect, preferably, the interval between the wavelength of the first emission peak and the wavelength of the second emission peak is larger than the interval between the wavelength of the first emission peak and the peak wavelength of the treatment light. large. When such a fluorescent light-sensitive substance is used, a predetermined wavelength through which the detector filter is transmitted is set between the peak wavelength of the therapeutic light and the wavelength of the first emission peak of fluorescence, as compared with the case where a predetermined wavelength is set. Since the interval from the peak wavelength of the treatment light is larger in the second emission peak than in the first emission peak, the detector filter is passed between the peak wavelength of the treatment light and the wavelength of the second emission peak of fluorescence. A predetermined wavelength can be easily set.

In the medical image imaging apparatus in the first aspect, the therapeutic light is preferably light having a peak wavelength in a wavelength region of 650 nm or more and 700 nm or less. Here, the red wavelength region is from about 610 nm to about 750 nm. In addition, the color of light apparently approaches black because the sensitivity of the human eye decreases as it approaches the boundary of the visible light region. Therefore, when using such a photosensitive substance that emits fluorescence, by setting the wavelength of the therapeutic light in the wavelength region of 650 nm or more and 700 nm or less, as compared with the case of irradiating the therapeutic light of less than 650 nm, the subject is covered. It is possible to prevent the irradiation range from being illuminated in red by the excitation light irradiated to the examiner.

In the medical image imaging apparatus according to the first aspect, preferably, the wavelength of the first emission peak is included in the region of 700 nm or more and less than 750 nm, and the wavelength of the second emission peak is included in the region of 750 nm or more and less than 800 nm. .. By using a fluorescent light-sensitive substance having such a peak wavelength, it is possible to set the upper limit of the size of a predetermined wavelength transmitted by the detector filter in the range of 700 nm or more and less than 750 nm. As a result, the upper limit of the size of the predetermined wavelength transmitted by the detector filter can be set to a wavelength region preferable for removing the light of the indoor lighting.

The medical image imaging apparatus according to the second aspect of the present invention acquires an image of a treatment target site during treatment by irradiating a light-sensitive substance accumulated in the treatment target site in a subject with treatment light to generate an image. A medical image imaging device, which is a detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from a light-sensitive substance by irradiating with therapeutic light, and a detection that detects the fluorescence transmitted through the detector filter. It includes a device and an image generator that generates an image based on the output of the detector, fluorescence has at least a first emission peak and a second emission peak, and the wavelength of the first emission peak is the second emission peak. It is a wavelength equal to or less than the wavelength of, and is not included in the wavelength region of the light emitted by the indoor illumination. The wavelength of the second emission peak is a wavelength included in the wavelength region of the light emitted by the indoor illumination, and the predetermined wavelength is This is the wavelength of the first emission peak.

In the medical image imaging apparatus according to the second aspect of the present invention, as described above, among the fluorescence emitted from the photosensitive substance, at least the wavelength of the first emission peak not included in the wavelength region of the light emitted by the indoor lighting. A detector filter that transmits light having a predetermined wavelength is provided. As a result, even when the wavelength of the second emission peak of fluorescence emitted by the photosensitive substance is included in the wavelength region of the light emitted by the indoor lighting, the detector filter can remove the light in the wavelength region of the light emitted by the indoor lighting. it can. As a result, the light of the room illumination is superimposed on the fluorescence image when the fluorescence image is generated based on the fluorescence emitted by the photosensitizer injected into the subject, as in the medical image imaging apparatus according to the first aspect. , It is possible to suppress deterioration of the image quality of the fluorescent image.

In the medical image imaging apparatus in the second aspect, the detector filter is configured to transmit light having a wavelength shorter than the wavelength of the second emission peak, including a predetermined wavelength. With this configuration, for example, when the wavelength of the second emission peak of fluorescence emitted by the photosensitive substance is included in the wavelength region of the light of the indoor lighting, it can be removed by the detector filter. As a result, it is possible to suppress the reflection of the light of the indoor illumination in the wavelength region of the second emission peak on the fluorescence image.

In the medical image imaging apparatus according to the second aspect, preferably, the detector filter is configured to transmit light having a wavelength shorter than the lower limit wavelength of the wavelength region of the light emitted by the indoor lighting, including a predetermined wavelength. There is. With this configuration, among the fluorescence emitted by the photosensitive substance, the fluorescence having a wavelength shorter than the lower limit wavelength of the wavelength region of the light emitted by the indoor lighting can be detected. As a result, it is possible to further suppress the superimposition of the light of the room lighting on the fluorescent image when generating the fluorescent image, so that it is possible to further suppress the deterioration of the image quality of the fluorescent image. ..

According to the present invention, as described above, when a fluorescence image is generated based on the fluorescence emitted by a light-sensitive substance injected into a subject, light other than the fluorescence emitted by the light-sensitive substance such as indoor lighting is a fluorescence image. It is possible to provide a medical image imaging apparatus capable of suppressing deterioration of the image quality of a fluorescent image by being superimposed on the image.

It is a block diagram which showed the outline of the treatment support system provided with the medical image imaging apparatus according to 1st Embodiment of this invention. It is a perspective view of the medical image imaging apparatus according to 1st Embodiment of this invention. It is the schematic of the image pickup part of the medical image imaging apparatus according to 1st Embodiment of this invention. It is a block diagram which showed the outline of the inside of the image pickup part of the medical image imaging apparatus according to 1st Embodiment of this invention. It is a schematic diagram of the whole configuration of the treatment support system including the medical image imaging apparatus according to the 1st Embodiment of this invention. FIG. 5 is a schematic view (cross-sectional view) showing a state in which a treatment support system provided with a medical image imaging device according to the first embodiment of the present invention generates fluorescence of a light-sensitive substance. In the schematic diagram (A) of the fluorescence image displayed on the display unit by the medical image imaging apparatus according to the first embodiment of the present invention, the schematic diagram (B) of the visible light image, and the schematic diagram (C) of the composite image obtained by synthesizing them. is there. It is a schematic diagram of the spectrum of the light-sensitive substance administered to a subject. A schematic diagram (A) of a fluorescent image when the light of indoor lighting is reflected in a fluorescent image captured by the medical image imaging device according to the first embodiment of the present invention, a schematic diagram (B) of a visible light image, and a combination thereof. It is a schematic diagram (C) of the composite image. It is a schematic diagram for demonstrating the structure which the 1st filter by 1st Embodiment of this invention transmits light. It is a schematic diagram for demonstrating the wavelength region of the light transmitted through the 1st filter according to 1st Embodiment of this invention. It is a block diagram which showed the outline of the treatment support system provided with the medical image imaging apparatus according to 2nd Embodiment of this invention. It is the schematic of the excitation light source and the 2nd filter by 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the structure which transmits light by the 1st filter and the 2nd filter by the 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the wavelength region of the light transmitted through the 2nd filter according to 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the structure which the 3rd filter by the 3rd Embodiment of this invention transmits light. It is a schematic diagram for demonstrating the wavelength region of the light transmitted through the 3rd filter according to the 3rd Embodiment of this invention. It is a schematic diagram for demonstrating the structure which the 4th filter by 4th Embodiment of this invention transmits light. It is a schematic diagram for demonstrating the wavelength region of the light transmitted through the 4th filter according to 4th Embodiment of this invention.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

[First Embodiment]
The configuration of the treatment support system 100 including the medical image imaging device 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 11.

(Structure of treatment support system)
As shown in FIG. 1, the treatment support system 100 provided with the medical image imaging device 1 according to the first embodiment includes the medical image imaging device 1 and the display device 30. The medical image imaging device 1 generates an image by irradiating the photosensitizer Pa accumulated in the treatment target site in the subject P with excitation light EL (treatment light) to image the treatment target site during treatment. It is a medical image imaging device, and by irradiating the excitation light EL, the fluorescent IR emitted from the photosensitive substance Pa administered to the subject P is detected, and the cancer cells 20 (see FIG. 7) are visualized. It is configured to assist the surgeon Q (see Figure 5) surgery. The detailed configuration of the medical image imaging device 1 will be described later. The excitation light EL is an example of "therapeutic light" in the claims.

Further, the display device 30 is configured to display the captured image 16 (see FIG. 7) of the subject P output from the medical image capturing device 1. The display device 30 is, for example, a monitor such as a liquid crystal display.

(Configuration of medical image imaging device)
As shown in FIG. 1, the medical image imaging device 1 according to the first embodiment includes an imaging unit 5 including a light receiving unit 2, an optical system 3, and a light source unit 4, an arm mechanism 6, and a housing 7.

The light receiving unit 2 includes a visible light detection unit 8 and a fluorescence detection unit 9. The visible light detection unit 8 is configured to detect visible light Vis. Further, the fluorescence detection unit 9 is configured to detect the fluorescence IR. The detailed configuration of the visible light detection unit 8 and the fluorescence detection unit 9 will be described later. The fluorescence detection unit 9 is an example of a "detector" within the scope of the claims.

The optical system 3 includes a zoom lens 10, a prism 11, and a first filter 12. The optical system 3 is configured to separate the visible light Vis reflected from the subject P and the fluorescent IR emitted from the photosensitive substance Pa by being irradiated with the excitation light EL, and to separate the fluorescent IR. ing. The detailed configuration of the optical system 3 will be described later. The first filter 12 is an example of a "detector filter" in the claims.

The light source unit 4 directs the visible light source 4a that irradiates the subject P (patient) with visible light Vis and the excitation light EL for exciting the photosensitive substance Pa administered into the body of the subject P toward the subject P. It is provided with an excitation light source 4b for irradiating light. The visible light source 4a and the excitation light source 4b include, for example, a light emitting diode (LED). The light-sensitive substance Pa is, for example, IR700. IR700 is a drug in which a substance that emits fluorescent IR by absorbing excitation light EL and an antibody that selectively binds to cancer cells 20 are bound. IR700 is a drug used in near-infrared photoimmunotherapy (NIR-PIT) that is administered to subject P and kills cancer cells 20 by irradiating with excitation light EL.

Here, IR700 has a property of specifically binding to cancer cells 20. Therefore, in NIR-PIT, by irradiating the IR700 with excitation light EL (therapeutic light), only the cancer cells 20 can be destroyed by the heat generated from the IR700. In addition, the IR700 does not emit fluorescent IR when the cancer cells 20 are destroyed. Therefore, in NIR-PIT, the therapeutic effect can be confirmed by acquiring the intensity of the fluorescent IR generated by irradiating the therapeutic light. That is, when the intensity of the fluorescence IR immediately after irradiation with the therapeutic light is set to 100, the therapeutic effect can be confirmed by whether or not the fluorescence IR is reduced by a predetermined percentage. Further, in NIR-PIT, since the fluorescent IR is emitted from the IR 700 bound to the cancer cell 20, it is possible to grasp whether or not the therapeutic light is correctly applied by the intensity change of the fluorescent IR before and after the treatment. Further, even if the cancer cell 20 is located at a position different from the expected position, the position of the cancer cell 20 can be grasped and treated by detecting the fluorescent IR from the IR700.

The housing 7 includes a control unit 13, an image generation unit 14, and a storage unit 15. The housing 7 is, for example, a trolley in which a PC (Personal Computer) is built. The control unit 13 is configured to control irradiation of light (visible light Vis, excitation light EL) from the light source unit 4, stop of irradiation, and the like based on an input operation by an operation unit (not shown). The control unit 13 is composed of, for example, a processor such as a CPU (Central Processing Unit).

The image generation unit 14 is configured to generate a fluorescence image 16a (see FIG. 7) based on the signal detected by the fluorescence detection unit 9. Further, the image generation unit 14 is configured to generate a visible light image 16b (see FIG. 7) based on the signal detected by the visible light detection unit 8. Further, the image generation unit 14 is configured to generate a composite image 16c (see FIG. 7) in which the fluorescence image 16a and the visible light image 16b are combined. The image generation unit 14 includes, for example, a processor such as a GPU (Graphics Processing Unit) or an FPGA (Field-Programmable Gate Array) configured for image processing.

Further, the storage unit 15 is configured to store the image 16 and the like generated by the image generation unit 14. The storage unit 15 includes, for example, a non-volatile memory or a hard disk drive (HDD).

FIG. 2 is a perspective view of the medical image imaging apparatus 1 according to the first embodiment. The housing 7 includes four wheels 70, an arm mechanism 6 provided on the upper surface of the housing 7 near the front in the traveling direction of the housing 7, and an imaging unit provided on the arm mechanism 6 via a sub-arm 50. 5 and a monitor 72 are provided. A handle 71 used when moving the housing 7 is provided behind the housing 7 in the traveling direction. Further, a recess 73 for mounting an operation unit (not shown) used for remote control of the medical image imaging device 1 is formed on the upper surface of the housing 7.

The arm mechanism 6 is provided on the front side (opposite side of the handle 71) of the housing 7 in the traveling direction. The arm mechanism 6 includes a first arm member 60 connected by a hinge portion 62 to a support portion 66 arranged on a support column 65 provided on the front side in the traveling direction of the housing 7. The first arm member 60 can swing around the hinge portion 62 with respect to the housing 7 via the support column 65 and the support portion 66. The monitor 72 is installed on the support column 65.

A second arm member 61 is connected to the upper end of the first arm member 60 by a hinge portion 63. The second arm member 61 can swing with respect to the first arm member 60 via the hinge portion 63. Therefore, the first arm member 60 and the second arm member 61 are configured so that their angles can be freely adjusted.

A support portion 52 is connected to the lower end of the second arm member 61 by a hinge portion 64. The support portion 52 can swing with respect to the second arm member 61 via the hinge portion 64. The support portion 52 is provided with a rotating shaft 51. Then, the sub-arm 50 that supports the image pickup unit 5 rotates about a rotation shaft 51 provided at the tip of the second arm member 61. Therefore, the imaging unit 5 refers to the position on the front side of the housing 7 in the traveling direction with respect to the arm mechanism 6 and the posture when the housing 7 is moved by the rotation of the sub-arm 50. It moves between the position on the rear side (handle 71 side) of the housing 7 in the traveling direction.

FIG. 3 is a schematic view of an imaging unit 5 of the medical image imaging apparatus 1 according to the first embodiment. The image pickup unit 5 houses the above-mentioned light receiving unit 2, the optical system 3, and the light source unit 4 in the image pickup unit 5. In the example of FIG. 3, the visible light source 4a and the excitation light source 4b are each composed of six LEDs. The visible light source 4a is configured to irradiate, for example, white light including a plurality of wavelengths in the visible region as visible light Vis to irradiate the subject P. Further, the excitation light source 4b is configured to irradiate the subject P with the excitation light EL having the first wavelength 42 (see FIG. 8) as the peak wavelength as the excitation light EL for exciting the photosensitive substance Pa. Has been done.

FIG. 4 is a schematic view of the light receiving unit 2 and the optical system 3 of the medical image imaging device 1 according to the first embodiment. The light receiving unit 2 includes a visible light detection unit 8 and a fluorescence detection unit 9. Further, the optical system 3 includes a zoom lens 10, a prism 11, and a first filter 12 that are reciprocally moved in the optical axis L direction by a lens moving mechanism (not shown) for focusing. The prism 11 is installed between the zoom lens 10 and the first filter 12. The first filter 12 is installed between the prism 11 and the fluorescence detection unit 9.

The visible light detection unit 8 is configured to detect visible light Vis that is irradiated from the visible light source 4a and reflected by the subject P. Further, the fluorescence detection unit 9 is configured to detect the fluorescence IR generated from the photosensitive substance Pa administered into the body of the subject P by the excitation light EL emitted from the excitation light source 4b. The visible light detection unit 8 and the fluorescence detection unit 9 are composed of, for example, image sensors such as CMOS (Completion General Oxide Semiconductor) and CCD (Charge Coupled Device), respectively. As the visible light detection unit 8, one capable of capturing the visible light image 16b as a color image is used.

The visible light detection unit 8 and the fluorescence detection unit 9 are configured to detect the visible light Vis and the fluorescence IR by a common optical system 3 when detecting the visible light Vis and the fluorescence IR. Specifically, the visible light Vis and the fluorescent IR incident on the light receiving unit 2 along the optical axis L reach the prism 11 after passing through the zoom lens 10. Of the incident visible light Vis and fluorescent IR, the visible light Vis is reflected by the prism 11 and is incident on the visible light detection unit 8. Of the incident visible light Vis and fluorescent IR, the fluorescent IR passes through the prism 11 and is incident on the first filter 12. Among the incident fluorescent IRs, the fluorescent IRa (dotted chain line) having a wavelength larger than the first wavelength 42 (see FIG. 8) passes through the first filter 12. Further, among the incident fluorescent IRs, the fluorescent IRb (broken line) having a wavelength shorter than the first wavelength 42 is removed by the first filter 12. Therefore, the fluorescence IRa having a wavelength of a predetermined first wavelength 42 or more reaches the fluorescence detection unit 9. In other words, the fluorescence IRa having a wavelength larger than the predetermined first wavelength 42 is detected by the fluorescence detection unit 9, and the fluorescence IRb having a wavelength shorter than the predetermined first wavelength 42 is detected by the fluorescence detection unit 9. Not detected by. The first filter 12 includes, for example, a color filter.

FIG. 5 is a diagram showing the overall configuration of the treatment support system 100. The treatment support system 100 is configured as a treatment support system that provides treatment support by capturing a visible light image 16b and a fluorescence image 16a of the subject P being treated and displaying them on the display device 30. As shown in FIG. 5, the medical image imaging device 1 is configured to image the subject P from above the subject P when the surgeon Q performs an operation on the subject P. Specifically, as shown in FIG. 6, the photosensitive substance Pa inside the subject P generates fluorescent IR by the excitation light EL emitted from the excitation light source 4b provided in the medical image imaging device 1. Let me. Then, the fluorescence detection unit 9 provided in the medical image imaging device 1 detects the fluorescence IR generated from the light-sensitive substance Pa inside the subject P.

In the first embodiment, the medical image imaging device 1 is configured to image, for example, the tissue 21 containing the cancer cells 20 of the subject P. FIG. 7 is a schematic view showing an example of the image 16 displayed on the display device 30. In the first embodiment, an example is shown in which the cancer-affected tissue 21 is imaged and displayed on the display device 30. FIG. 7A is a schematic view of the fluorescence image 16a of the cancer cell 20. FIG. 7B is a schematic view of the visible light image 16b. Further, FIG. 7C is a schematic view of a composite image 16c in which a fluorescence image 16a and a visible light image 16b are combined.

In the first embodiment, the medical image imaging device 1 synthesizes the fluorescence image 16a and the visible light image 16b of the cancer cells 20 to generate a composite image 16c, and generates the fluorescence image 16a, the visible light image 16b, and the composite image 16c. Is configured to be output to the display device 30. Further, as shown in FIG. 7, the display device 30 is configured to display the fluorescence image 16a, the visible light image 16b, and the composite image 16c, respectively.

The light-sensitive substance Pa will be described with reference to FIG. Graph 40 (solid line) shown in FIG. 8 is an absorption spectrum of the light-sensitive substance Pa. Further, the graph 41 (dashed line) shown in FIG. 8 is a spectrum of fluorescence IR emitted from the photosensitive substance Pa irradiated with the excitation light EL. The horizontal axis of the graph 40 and the graph 41 is the wavelength. The vertical axis of Graph 40 and Graph 41 is the normalized intensity of absorption and fluorescence.

As shown in Graph 40 of FIG. 8, the light-sensitive substance Pa has a first absorption peak 40a having an absorption peak wavelength in a wavelength region of about 650 nm or more and less than about 700 nm. Further, the light-sensitive substance Pa has a second absorption peak 40b having an absorption peak wavelength in a wavelength region of about 600 nm or more and less than about 650 nm. The excitation light EL irradiated to the light-sensitive substance Pa may be light of any wavelength as long as it is within the range of the graph 40. Further, the excitation light EL irradiated to the photosensitive substance Pa does not have to match the wavelength of the excitation light EL with the wavelength of the absorption peak. In the first embodiment, the excitation light EL emitted from the excitation light source 4b is, for example, light having a peak wavelength in a wavelength region of about 650 nm or more and about 700 nm or less. Specifically, the excitation light source 4b is configured to irradiate the excitation light EL having the same peak wavelength as the wavelength of the first absorption peak 40a. In the first embodiment, for example, the excitation light source 4b is configured to irradiate excitation light EL having a peak wavelength of about 690 nm.

As shown in Graph 41 of FIG. 8, the fluorescent IR emitted from the light-sensitive substance Pa has at least a first emission peak 41a and a second emission peak 41b. As shown in Graph 41, the intensity of the first emission peak 41a is higher than the intensity of the second emission peak 41b. The wavelength of the first emission peak 41a is a wavelength equal to or less than the wavelength of the second emission peak 41b, and is a wavelength included in the wavelength region of the light FL (see FIG. 10) emitted by the indoor lighting. The wavelength of the second emission peak 41b is a wavelength that is not included in the wavelength region of the light FL emitted by the indoor lighting. Specifically, the first emission peak 41a of the fluorescent IR emitted from the light-sensitive substance Pa is included in a region having a wavelength of about 700 nm or more and less than 750 nm. Further, the second emission peak 41b of the fluorescent IR emitted from the light-sensitive substance Pa is contained in a region of about 750 nm or more and less than 800 nm. The interval d1 between the wavelength of the first emission peak 41a and the wavelength of the second emission peak 41b is larger than the interval d2 between the wavelength of the first emission peak 41a and the peak wavelength of the excitation light EL. The light FL for indoor lighting has a wavelength peak in the wavelength region of about 300 nm to about 710 nm.

As shown in Graph 41 of FIG. 8, the magnitude of the wavelength of the first emission peak 41a of the light-sensitive substance Pa is about 700 nm. Therefore, for example, when the light-sensitive substance Pa is irradiated with excitation light EL having a peak wavelength of about 620 nm and the fluorescence IR having the wavelength of the first emission peak 41a is detected by the fluorescence detection unit 9, the generated fluorescence image is generated. As shown in the fluorescence image 17a shown in FIG. 9A, the light FL of the room illumination is superimposed on the 16a. When the light FL of the room lighting is superimposed, the light FL of the room lighting is reflected in the fluorescence image 17a, and the S / N ratio is lowered. If the image quality of the fluorescent image 17a deteriorates, the image quality of the composite image 17c generated by synthesizing the fluorescent image 17a and the visible light image 17b may also deteriorate. In the examples shown in FIGS. 9 (A) and 9 (C), the reflection of the light FL of the indoor lighting is represented by hatched diagonal lines for convenience.

Therefore, in the first embodiment, the medical image capturing apparatus 1 has a fluorescence IRa larger than the wavelength region of the light FL of the room illumination by the first filter 12, and a wavelength region of the light FL of the room illumination and the light FL of the room illumination. It is configured to separate from the fluorescent IRb.

Specifically, the first filter 12 is configured to transmit light having at least a predetermined wavelength among the fluorescent IRs emitted from the photosensitive substance Pa injected into the subject P. More specifically, the first filter 12 is configured to transmit light having a wavelength longer than the wavelength of the first emission peak 41a including a predetermined wavelength. Further, the first filter 12 is configured to transmit light having a wavelength longer than the upper limit wavelength of the wavelength region of the light FL emitted by the indoor lighting, including a predetermined wavelength. The predetermined wavelength is the wavelength of the second emission peak 41b.

FIG. 10 is a schematic diagram for explaining the light reaching the fluorescence detection unit 9. As shown in FIG. 10A, the light FL of the room illumination and the fluorescent IR emitted from the photosensitive substance Pa irradiated with the excitation light EL are incident on the first filter 12. As shown in FIG. 10B, of the indoor illumination light FL and the fluorescent IR incident on the first filter 12, the indoor illumination optical FL and the fluorescent IRb having a wavelength shorter than the first wavelength 42 are the first filter. Removed by 12. Further, of the light FL and the fluorescence IR of the room illumination incident on the first filter 12, the fluorescence IRa having a wavelength of the first wavelength 42 or more passes through the first filter 12 and reaches the fluorescence detection unit 9.

Due to the structure of the first filter 12, it is difficult to accurately transmit only light having a wavelength of a predetermined wavelength. Therefore, in the first embodiment, it is configured to transmit light having a wavelength larger than the first wavelength 42, which is shorter than a predetermined wavelength. In other words, the first filter 12 is between the wavelength of the first emission peak 41a and the wavelength of the second emission peak 41b in the fluorescence IR emitted from the photosensitive substance Pa by the excitation light EL emitted from the excitation light source 4b. It is configured to remove light having a wavelength shorter than the first wavelength 42 in.

The first wavelength 42 is a wavelength included in the range of about 700 nm or more and less than about 770 nm. Further, the first wavelength 42 is a wavelength having a size closer to the second emission peak 41b of the fluorescence IR than the first emission peak 41a of the fluorescence IR. In the first embodiment, the first wavelength 42 is, for example, a wavelength of about 750 nm. By setting the size of the first wavelength 42, which is the upper limit of the wavelength to be removed by the first filter 12, to about 750 nm, the first filter 12 can transmit the fluorescence IR having a predetermined wavelength, and the fluorescence detection unit 9 can suppress the detection of the light FL of the indoor lighting. As shown in the graph 46 of FIG. 11, the first filter 12 is configured such that the transmittance gradually increases from a wavelength smaller than the first wavelength 42, for example. That is, the first filter 12 is configured to transmit light having a wavelength around the first wavelength 42 in the wavelength region 45 centered on the first wavelength 42. Therefore, if the size of the first emission peak 42 is too close to the first emission peak 41a, light having a wavelength smaller than that of the first emission peak 41a may pass through the first filter 12. Therefore, it is preferable that the size of the first wavelength 42 is set in consideration of the size of the wavelength region 45. In the graph 46 of FIG. 11, the horizontal axis is the wavelength and the vertical axis is the transmittance of light (excitation light EL).

(Effect of the first embodiment)
In the first embodiment, the following effects can be obtained.

In the first embodiment, as described above, the medical image capturing apparatus 1 transmits light having at least a predetermined wavelength among the fluorescent IRs emitted from the photosensitive substance Pa by irradiating the excitation light EL (therapeutic light). A first filter 12 is provided, a fluorescence detection unit 9 that detects fluorescence IR (IRa) that has passed through the first filter 12, and an image generation unit 14 that generates a fluorescence image 16a based on the output of the fluorescence detection unit 9. The fluorescence IR has at least a first emission peak 41a and a second emission peak 41b, and the wavelength of the first emission peak 41a is a wavelength equal to or less than the wavelength of the second emission peak 41b. The wavelength included in the wavelength region, the wavelength of the second emission peak 41b is a wavelength not included in the wavelength region of the light FL emitted by the indoor illumination, and the predetermined wavelength is the wavelength of the second emission peak 41b. As a result, the light FL emitted by the indoor lighting can be removed by the first filter 12. That is, among the fluorescent IRs from the light-sensitive substance Pa, the light (fluorescent IRb) included in the wavelength region of the wavelength of the light FL of the indoor illumination is intentionally removed together with the light FL of the indoor illumination, and the wavelength of the light FL of the indoor illumination is changed. The fluorescence image 16a can be generated by fluorescence IR (IRa) having a wavelength longer than that in the wavelength region. Therefore, it is possible to suppress an increase in the background when the fluorescent image 16a is generated based on the fluorescence IR emitted by the photosensitive substance Pa injected into the subject P. Further, since it is possible to suppress an increase in the background, it is possible to suppress an increase in noise even when a fluorescent image 16a is generated using a high-resolution image sensor. As a result, when the fluorescent image 16a is generated based on the fluorescence IR (IRa) emitted by the photosensitive substance Pa injected into the subject P, the light FL of the room illumination is superimposed on the fluorescent image 16a, and the fluorescent image 16a is superimposed. It is possible to suppress the deterioration of the image quality of the image.

Further, in the first embodiment, as described above, the first filter 12 is configured to transmit light having a wavelength longer than the wavelength of the first emission peak 41a, including a predetermined wavelength. As a result, for example, when the wavelength of the fluorescent IR emitted by the light-sensitive substance Pa is included in the wavelength region of the optical FL of the indoor lighting, the light FL emitted by the indoor lighting included in the wavelength region of the first emission peak 41a or less is included. It can be removed by the first filter 12. As a result, it is possible to suppress the reflection of the light FL of the indoor illumination in the wavelength region of the excitation light EL on the fluorescence image 16a.

Further, in the first embodiment, as described above, the first filter 12 is configured to transmit light having a wavelength longer than the upper limit wavelength of the wavelength region of the light FL emitted by the indoor lighting, including a predetermined wavelength. There is. Thereby, among the fluorescent IRs emitted by the light-sensitive substance Pa, the fluorescent IR having a wavelength longer than the first wavelength 42, which is longer than the upper limit wavelength of the wavelength region of the light FL emitted by the indoor lighting, can be detected. As a result, it is possible to further suppress the superimposition of the light FL of the indoor lighting on the fluorescent image 16a when the fluorescent image 16a is generated, so that the deterioration of the image quality of the fluorescent image 16a is further suppressed. can do.

Further, in the first embodiment, as described above, the intensity of the first emission peak 41a is higher than the intensity of the second emission peak 41b. By using such a light-sensitive substance Pa that emits fluorescent IR, for example, even when the wavelength of the first emission peak 41a is included in the wavelength region of the light FL emitted by the indoor illumination, the wavelength of the first emission peak 41a is used. The fluorescence IR of the above can be intentionally removed together with the light FL of the indoor illumination, and an image can be generated by the fluorescence IR of the second emission peak 41b. As a result, the S / N ratio of the light of the second emission peak 41b, which is lower than the intensity of the first emission peak 41a, can be improved by removing the light contained in the wavelength region of the light FL emitted by the indoor lighting. Therefore, even if the light of the second emission peak 41b is used, it is possible to suppress the deterioration of the image quality of the fluorescent image 16a.

Further, in the first embodiment, as described above, the interval d1 between the wavelength of the first emission peak 41a and the wavelength of the second emission peak 41b is the wavelength of the first emission peak 41a and the excitation light EL (therapeutic light). It is larger than the interval d2 from the peak wavelength. If the photosensitive substance Pa that emits such fluorescence IR is used, a predetermined first wavelength 42 that allows the first filter 12 to pass between the peak wavelength of the excitation light EL and the wavelength of the first emission peak 41a of the fluorescence IR. Since the interval from the peak wavelength of the excitation light EL is larger in the second emission peak 41b than in the first emission peak 41a, the peak wavelength of the excitation light EL and the second emission of the fluorescence IR are larger than in the case of setting. A predetermined first wavelength 42 through which the first filter 12 is transmitted can be easily set between the wavelength of the peak 41b and the wavelength.

Further, in the first embodiment, as described above, the excitation light EL (therapeutic light) is light having a peak wavelength in a wavelength region of 650 nm or more and 700 nm or less. Here, the red wavelength region is from about 610 nm to about 750 nm. In addition, the color of light apparently approaches black because the sensitivity of the human eye decreases as it approaches the boundary of the visible light region. Therefore, when using such a photosensitive substance Pa that emits fluorescent IR, by setting the wavelength of the excitation light EL in the wavelength region of 650 nm or more and 700 nm or less, it is compared with the case of irradiating the excitation light EL of less than 650 nm. Therefore, it is possible to prevent the irradiation range from being illuminated in red by the excitation light EL irradiated to the subject P.

Further, in the first embodiment, as described above, the wavelength of the first emission peak 41a is included in the region of 700 nm or more and less than 750 nm, and the wavelength of the second emission peak 41b is included in the region of 750 nm or more and less than 800 nm. .. When the photosensitive substance Pa that emits fluorescent IR having such a peak wavelength is used, the upper limit of the size of the first wavelength 42 may be set in the range of 700 nm or more and less than 750 nm. As a result, the upper limit of the size of the predetermined wavelength transmitted by the first filter 12 can be set to a wavelength region preferable for removing the light FL of the indoor lighting.

[Second Embodiment]
Next, the treatment support system 200 including the medical image imaging device 19 according to the second embodiment of the present invention will be described with reference to FIGS. 8 and 12 to 15. Unlike the first embodiment in which the subject P is irradiated with the excitation light EL having a predetermined peak wavelength, in the second embodiment, the medical image imaging device 19 emits the excitation light EL from the irradiated photosensitive substance Pa. Excitation light having a wavelength longer than a predetermined second wavelength 43 (see FIG. 8) between the wavelength of the first emission peak 41a of the fluorescent IR and the wavelength of the second emission peak 41b longer than the first emission peak 41a. A second filter 18 (see FIG. 12) for removing EL is further provided. The same components as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 12 is a schematic view showing the overall configuration of the treatment support system 200 including the medical image imaging device 19 according to the second embodiment. As shown in FIG. 12, the medical image imaging apparatus 19 has the wavelength of the first emission peak 41a (see FIG. 8) of the fluorescence IR emitted from the photosensitive substance Pa irradiated with the excitation light EL, and the first emission peak 41a. A second filter 18 is further provided to remove the excitation light EL having a wavelength longer than the predetermined second wavelength 43 (see FIG. 8) between the wavelength of the longer second emission peak 41b (see FIG. 8).

As shown in FIG. 13, the excitation light EL emitted from the excitation light source 4b is incident on the second filter 18. The second filter 18 is configured to transmit the excitation light ELa (dashed line) having a length less than the second wavelength 43 among the incident excitation light ELs. Therefore, in the excitation light EL incident on the second filter 18, the excitation light ELb having a wavelength longer than the second wavelength 43 is removed, and the excitation light ELa having a wavelength less than the second wavelength 43 is irradiated to the subject P. The second filter 18 includes, for example, a color filter.

As shown in FIG. 8, the first wavelength 42 is a wavelength longer than the second wavelength 43. In the second embodiment, the second wavelength 43 is, for example, a wavelength of about 720 nm. Further, as shown in FIG. 8, a common wavelength region 44 exists in the wavelength region separated by the first filter 12 and the wavelength region separated by the second filter 18. The larger the size of the common wavelength region 44, the larger the difference between the first wavelength 42 and the second wavelength 43. Therefore, the first filter 12 is larger than the upper limit of the excitation light ELa separated by the second filter 18. Since the upper limit of the fluorescence IRb removed by is increased, it is possible to further suppress the excitation light EL from being incident on the fluorescence detection unit 9.

FIG. 14 is a schematic diagram for explaining the light reaching the fluorescence detection unit 9. As shown in FIG. 14A, among the excitation light ELs emitted from the excitation light source 4b, the excitation light ELbs having a wavelength of the second wavelength 43 or higher are removed by the second filter 18. Further, among the excitation light EL emitted from the excitation light source 4b, the excitation light ELa having a wavelength less than the second wavelength 43 passes through the second filter 18 and is irradiated to the light-sensitive substance Pa. As shown in FIG. 14 (b), the photosensitive substance Pa irradiated with the excitation light ELa emits fluorescent IR. As shown in FIG. 14 (c), among the fluorescent IRs emitted from the light-sensitive substance Pa, the fluorescent IR having a wavelength of the first wavelength 42 or higher passes through the first filter 12 and has a wavelength shorter than the first wavelength 42. Of the excitation light ELa reflected from the fluorescent IR and the body surface of the subject P, the excitation light ELa having a wavelength shorter than the first wavelength 42 is removed by the first filter 12. The fluorescence IRa that has passed through the first filter 12 is detected by the fluorescence detection unit 9 and imaged.

Similar to the first filter 12, it is difficult for the second filter 18 to accurately remove light with the size of the second wavelength 43 due to its structure. As shown in the graph 48 of FIG. 15, the second filter 18 is configured such that the transmittance gradually decreases from a wavelength smaller than the second wavelength 43, for example. That is, the second filter 18 is configured to transmit light having a wavelength around the second wavelength 43 in the wavelength region 47 centered on the second wavelength 43. Therefore, if the size of the second emission peak 43 is too close to the second emission peak 41b, light having a wavelength larger than that of the second emission peak 41b may pass through the second filter 18. Further, when the magnitude of the second wavelength 43 is made too close to the first wavelength 42, among the excitation light ELa transmitted through the second filter 18, the excitation light ELa reflected by the body surface of the subject P or the like is the first filter. There is a possibility of passing through 12. Therefore, it is preferable that the size of the second wavelength 43 is set in consideration of the size of the wavelength region 47. In the graph 48 of FIG. 15, the horizontal axis is the wavelength and the vertical axis is the transmittance of light (excitation light EL).

The other configurations of the second embodiment are the same as those of the first embodiment.

(Effect of the second embodiment)
In the second embodiment, the following effects can be obtained.

In the second embodiment, as described above, the wavelength of the first emission peak 41a of the fluorescence IR emitted from the photosensitive substance Pa irradiated with the excitation light EL and the second emission peak 41b longer than the first emission peak 41a. A second filter 18 for removing the excitation light EL having a wavelength longer than the predetermined second wavelength 43 between the wavelengths of the above is further provided. As a result, among the excitation light EL having a wavelength longer than the wavelength region of the indoor illumination light FL included in the excitation light EL, the wavelength component near the second emission peak 41b is suppressed from being irradiated to the subject P. Can be done. As a result, it is possible to suppress the irradiation of the wavelength component near the second emission peak 41b to the subject P, and even when the excitation light EL reflected by the subject P is detected by the fluorescence detection unit 9. It is possible to prevent the excitation light EL having a wavelength longer than that of the second emission peak 41b from being superimposed on the fluorescence image 16a.

Further, in the second embodiment, as described above, the first wavelength 42 is a wavelength longer than the second wavelength 43. As a result, the wavelength of the excitation light EL emitted from the excitation light source 4b can be easily made smaller than the upper limit wavelength that can be removed by the first filter 12. As a result, even when the excitation light EL is reflected by the subject P, the light having a wavelength shorter than the first wavelength 42 is removed by the first filter 12, so that the excitation light having a wavelength longer than the second emission peak 41b is removed. It is possible to further suppress the EL from being superimposed on the fluorescent image 16a.

The other effects of the second embodiment are the same as those of the first embodiment.

[Third Embodiment]
Next, the treatment support system 300 (see FIG. 1) including the medical image imaging device 80 (see FIG. 1) according to the third embodiment will be described with reference to FIGS. 1, 16 and 17. Unlike the first filter 12 of the first embodiment, which removes light having a wavelength shorter than the first wavelength 42, which is shorter than the wavelength of the second emission peak 41b, in the third embodiment, the third filter 81 is a second filter. It is configured to remove light having a wavelength shorter than the third wavelength 82, which is longer than the peak 42b. The same components as those in the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted. Further, the third filter 81 is an example of the "detector filter" in the claims.

In the third embodiment, the third filter 81 is configured to remove light having a wavelength shorter than the third wavelength 82, which is longer than the second peak 42b.

FIG. 16 is a schematic diagram for explaining the light reaching the fluorescence detection unit 9. As shown in FIG. 16A, the light FL of the room illumination and the fluorescent IR emitted from the photosensitive substance Pa irradiated with the excitation light EL are incident on the third filter 81. As shown in FIG. 16B, of the indoor illumination light FL and the fluorescent IR incident on the third filter 81, the indoor illumination optical FL and the fluorescent IRb having a wavelength shorter than the third wavelength 82 are the third filter. Removed by 81. Further, of the light FL and the fluorescence IR of the room illumination incident on the third filter 81, the fluorescence IRa having a wavelength of the third wavelength 82 or more passes through the third filter 81 and reaches the fluorescence detection unit 9.

As with the first filter 12 in the first embodiment, it is difficult for the third filter 81 in the third embodiment to accurately remove light at a size of the third wavelength 82 due to its structure. As shown in Graph 84 of FIG. 17, the third filter 81 is configured such that the transmittance gradually increases from a wavelength smaller than, for example, the third wavelength 82. That is, the third filter 81 is configured to transmit light having a wavelength around the third wavelength 82 in the wavelength region 83 centered on the third wavelength 82. Therefore, if the size of the third wavelength 82 is too close to the second emission peak 41b, light having a wavelength smaller than or equal to the second emission peak 41b may pass through the third filter 81. Therefore, it is preferable that the size of the third wavelength 82 is set in consideration of the size of the wavelength region 83. However, since the second emission peak 41b has a longer wavelength than the first emission peak 41a, the setting conditions of the third wavelength 82 are not stricter than those of the first wavelength 42 in the first embodiment. In the graph 84 of FIG. 17, the horizontal axis is the wavelength and the vertical axis is the transmittance of light (excitation light EL).

The other configurations of the third embodiment are the same as those of the first and second embodiments.

(Effect of Third Embodiment)
In the third embodiment, the following effects can be obtained.

In the third embodiment, as described above, the third filter 81 is configured to remove light having a wavelength shorter than the third wavelength 82, which is longer than the second emission peak 41b, and the fluorescence detection unit 9 is configured to remove light having a wavelength shorter than the third wavelength 82. , It is configured to detect a fluorescence IR having a wavelength longer than the third wavelength 82. As a result, it is possible to remove light having a wavelength shorter than the third wavelength 82, which is longer than the second emission peak 41b, so that light in the wavelength region of the light FL of the room illumination is more reliably reflected in the fluorescent image 16a. It is possible to suppress the intrusion. Further, since it is possible to transmit light having a wavelength longer than that of the second emission peak 41b, for example, even when ICG is used as the light-sensitive substance Pa, the fluorescence IR emitted by ICG without exchanging the third filter 81. It is possible to suppress the reflection of light in the wavelength region of the light FL of the room illumination on the fluorescent image 16a at the time of detecting. As a result, regardless of whether IR700 or ICG is used as the light-sensitive substance Pa, it is possible to suppress the reflection of light in the wavelength region of the light FL of the room illumination on the fluorescent image 16a without exchanging the third filter 81. Can be done.

The other effects of the third embodiment are the same as those of the first and second embodiments.

[Fourth Embodiment]
Next, the treatment support system 400 (see FIG. 1) including the medical image imaging device 90 (see FIG. 1) according to the fourth embodiment will be described with reference to FIGS. 1, 18 and 19. A light-sensitive substance Pa that emits fluorescent IR, in which the first emission peak 41a is a wavelength included in the wavelength region of the light FL of the room illumination and the second emission peak 41b is a wavelength longer than the wavelength of the light FL of the room illumination is used. Unlike the first embodiment, in the fourth embodiment, the first emission peak 41a has a wavelength shorter than the wavelength region of the light FL of the room illumination, and the second emission peak 41b is in the wavelength region of the light FL of the room illumination. A light-sensitive substance Pa that emits fluorescent IR, which is a wavelength included, is used. The same components as those in the first to third embodiments are designated by the same reference numerals, and the description thereof will be omitted. Further, the fourth filter 91 is an example of the "detector filter" in the claims.

In the fourth embodiment, as shown in FIG. 1, the medical image capturing apparatus 90 uses light having at least a predetermined wavelength among the fluorescent IRs emitted from the photosensitive substance Pa by irradiating the excitation light EL (therapeutic light). It is provided with a fourth filter 91 that transmits light, a fluorescence detection unit 9 that detects fluorescence IR that has passed through a detector filter, and an image generation unit 14 that generates an image based on the output of the fluorescence detection unit 9.

FIG. 18 is a schematic diagram for explaining the light reaching the fluorescence detection unit 9. As shown in FIG. 18, the fluorescent IR emitted by the light-sensitive substance Pa has at least a first emission peak 41a and a second emission peak 41b, and the wavelength of the first emission peak 41a is equal to or less than the wavelength of the second emission peak 41b. The wavelength of the second emission peak 41b is a wavelength included in the wavelength region of the light FL emitted by the indoor illumination, and the predetermined wavelength is a predetermined wavelength. This is the wavelength of the first emission peak 41a. In the fourth embodiment, the fourth filter 91 is configured to transmit light having a wavelength shorter than the wavelength of the second emission peak 41b, including a predetermined wavelength. Further, the fourth filter 91 is configured to transmit light having a wavelength shorter than the lower limit wavelength of the wavelength region of the light FL emitted by the indoor lighting, including a predetermined wavelength.

Specifically, as shown in Graph 94 of FIG. 19, the fourth filter 91 is configured such that the transmittance gradually decreases from a wavelength smaller than, for example, the fourth wavelength 92. That is, the fourth filter 91 is configured to transmit light having a wavelength around the fourth wavelength 92 in the wavelength region 93 centered on the fourth wavelength 92. In the graph 94 of FIG. 19, the horizontal axis is the wavelength and the vertical axis is the transmittance of light (excitation light EL).

The other configurations of the fourth embodiment are the same as those of the first and second embodiments.

(Effect of Fourth Embodiment)
In the fourth embodiment, the following effects can be obtained.

In the fourth embodiment, as described above, the medical image capturing apparatus 90 transmits light having at least a predetermined wavelength among the fluorescent IRs emitted from the photosensitive substance Pa by irradiating the excitation light EL (therapeutic light). The fourth filter 91 is provided, the fluorescence detection unit 9 for detecting the fluorescence IR transmitted through the fourth filter 91, and the image generation unit 14 for generating an image based on the output of the fluorescence detection unit 9, and the fluorescence IR is at least It has a first emission peak 41a and a second emission peak 41b, and the wavelength of the first emission peak 41a is a wavelength equal to or less than the wavelength of the second emission peak 41b and is included in the wavelength region of the light FL emitted by the indoor illumination. The wavelength of the second emission peak 41b is a wavelength included in the wavelength region of the light FL emitted by the indoor illumination, and the predetermined wavelength is the wavelength of the first emission peak 41a. As a result, even when the wavelength of the second emission peak 41b of the fluorescence IR emitted by the photosensitive substance Pa is included in the wavelength region of the light FL emitted by the indoor lighting, the wavelength region of the light FL emitted by the indoor lighting by the fourth filter 91 The light can be removed. As a result, similarly to the medical image imaging device 1 according to the first embodiment, when the fluorescence image 16a is generated based on the fluorescence IR emitted by the photosensitive substance Pa injected into the subject P, the light FL of the room illumination is generated. Is superimposed on the fluorescent image 16a, and deterioration of the image quality of the fluorescent image 16a can be suppressed.

Further, in the fourth embodiment, as described above, the fourth filter 91 is configured to transmit light having a wavelength shorter than the wavelength of the second emission peak 41b, including a predetermined wavelength. Thereby, for example, when the wavelength of the second emission peak 41b of the fluorescence IR emitted by the photosensitive substance Pa is included in the wavelength region of the light FL of the indoor lighting, it can be removed by the fourth filter 91. As a result, it is possible to suppress the reflection of the light FL of the indoor lighting in the wavelength region of the second emission peak 41b on the fluorescence image 16a.

Further, in the fourth embodiment, as described above, the fourth filter 91 is configured to transmit light having a wavelength shorter than the lower limit wavelength of the wavelength region of the light FL emitted by the indoor lighting, including a predetermined wavelength. There is. Thereby, among the fluorescent IRs emitted by the light-sensitive substance Pa, the fluorescent IR having a wavelength shorter than the lower limit wavelength of the wavelength region of the light FL emitted by the indoor lighting can be detected. As a result, it is possible to further suppress the superimposition of the light FL of the indoor lighting on the fluorescent image 16a when the fluorescent image 16a is generated, so that the deterioration of the image quality of the fluorescent image 16a is further suppressed. can do.

The other effects of the fourth embodiment are the same as those of the first to third embodiments.

(Modification example)
It should be noted that the embodiments disclosed this time are exemplary in all respects and are not considered to be restrictive. The scope of the present invention is shown by the scope of claims, not the description of the above-described embodiment, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims.

For example, in the first to fourth embodiments, an example in which a color filter is used as a detector filter and a light source filter has been shown, but the present invention is not limited to this. Any filter may be used as long as it is possible to separate light in a predetermined wavelength region. For example, a prism or the like may be used.

Further, in the first to fourth embodiments, an example is shown in which the first filter 12 (third filter 81, fourth filter 91) is arranged at a position away from the fluorescence detection unit 9 on the optical axis L. , The present invention is not limited to this. For example, the fluorescence detection unit 9 and the first filter 12 (third filter 81, fourth filter 91) may be arranged without being separated.

Further, in the first to fourth embodiments, as the excitation light EL, light having a peak wavelength in a wavelength region of about 650 nm or more and about 700 nm or less is used, but the present invention is not limited to this. For example, an excitation light EL having a peak wavelength near the second absorption peak 40b may be used. However, the absorption efficiency of the second absorption peak 40b is lower than that of the first absorption peak 40a, and the wavelength of the second absorption peak 40b is about 620 nm, so that the region irradiated with the excitation light EL is illuminated in red. It is preferable to use the excitation light EL having a peak wavelength in the vicinity of the absorption peak 40a (wavelength region of about 650 nm or more and about 700 nm or less).

Further, in the first to fourth embodiments, an example in which IR700 is used as the light-sensitive substance Pa has been shown, but the present invention is not limited to this. Any light-sensitive substance having a peak wavelength in the wavelength region of the light FL of indoor lighting and having a peak wavelength in a wavelength region larger than the wavelength region of the light FL of indoor lighting. May be good.

Further, in the first to fourth embodiments, an example in which the image generation unit 14 generates a visible light image 16b is shown, but the present invention is not limited to this. The image generation unit 14 may be configured to generate only the fluorescence image 16a.

Further, in the second embodiment, the second wavelength 43 is a wavelength smaller than the first wavelength 42, but the present invention is not limited to this. The second wavelength 43 and the first wavelength 42 may have the same magnitude.

Further, in the first to fourth embodiments, an example of the configuration in which the medical image imaging device 1 (19, 80, 90) is provided with the excitation light source 4b is shown, but the present invention is not limited to this. For example, a therapeutic light source for irradiating the subject P with therapeutic light may be separately provided, and the fluorescence detection unit 9 may be configured to detect the fluorescence IR emitted by the therapeutic light emitted from the therapeutic light source.

Further, in the first to fourth embodiments, the first filter 12, the second filter 18, the third filter 81, and the fourth filter 91 remove light of a predetermined wavelength or less (a predetermined wavelength or more) by a so-called long pass. Although an example of configuring as a filter (short pass filter) has been shown, the present invention is not limited to this. For example, the first filter 12, the second filter 18, the third filter 81, and the fourth filter 91 may be configured as a so-called bandpass filter that transmits light in a predetermined wavelength range.

Further, in the first to fourth embodiments, an example of a configuration used in an apparatus for treating a subject P by irradiating the subject P with therapeutic light has been shown, but the present invention is not limited to this. For example, the present invention can also be applied when photoimmunotherapy is performed using another medical device such as an endoscope.

1, 19, 80, 90 Medical image imaging device 4b Excitation light source 9 Fluorescence detector (detector)
12 First filter (detector filter)
14 Image generator 16 Image 41a Fluorescence first peak 41b Fluorescence second peak 42 First wavelength 43 Second wavelength 81 Third filter (detector filter)
82 3rd wavelength 85 4th wavelength 91 4th filter (detector filter)
EL, ELa, ELb Excitation light FL Indoor lighting light IR, IRa, IRb Fluorescence P Subject Pa Light-sensitive substance

In order to achieve the above object, the medical image imaging apparatus according to the first aspect of the present invention irradiates a light-sensitive substance accumulated in a treatment target site in a subject with therapeutic light to perform the treatment target site during treatment. It is a medical image imaging device that images and generates an image, and is a detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from a photosensitive substance by irradiating with therapeutic light, and a detector filter. It is provided with a detector that detects the fluorescence transmitted through the light and an image generation unit that generates an image based on the output of the detector. The fluorescence has at least a first emission peak and a second emission peak, and the first emission peak. The wavelength of the second emission peak is a wavelength equal to or less than the wavelength of the second emission peak and is included in the wavelength region of the light emitted by the indoor illumination, and the wavelength of the second emission peak is included in the wavelength region of the light emitted by the indoor illumination. is not wavelength, the predetermined wavelength is a wavelength der the second emission peak is, the intensity of the first emission peak is higher than the intensity of the second emission peak.

As described above, the medical image imaging apparatus according to the first aspect of the present invention transmits light having a predetermined wavelength that is not included in the wavelength region of the light emitted by the indoor lighting among the fluorescence emitted from the photosensitive substance. It is equipped with a detector filter. As a result, the detector filter can remove the light in the wavelength region of the light emitted by the room lighting. That is, among the fluorescence from the light-sensitive substance, the light contained in the wavelength region of the indoor illumination light is intentionally removed together with the indoor illumination light, and an image is generated by the fluorescence having a wavelength longer than the wavelength region of the indoor illumination light. Can be done. Therefore, it is possible to suppress an increase in the background when a fluorescent image is generated based on the fluorescence emitted by the photosensitive substance injected into the subject. In addition, since it is possible to suppress an increase in the background, it is possible to suppress an increase in noise even when a fluorescent image is generated using a high-resolution image sensor. As a result, when a fluorescent image is generated based on the fluorescence emitted by the photosensitive substance injected into the subject, the light of the room illumination is superimposed on the fluorescent image, and the deterioration of the image quality of the fluorescent image is suppressed. Can be done. Further, if such a light-sensitive substance that emits fluorescence is used, for example, even if the wavelength of the first emission peak is included in the wavelength region of the light emitted by the indoor illumination, the fluorescence of the wavelength of the first emission peak can be obtained. An image can be generated by the fluorescence of the second emission peak, which is intentionally removed together with the light of the room illumination. As a result, by removing the light contained in the wavelength region of the light of the indoor lighting, it is possible to improve the S / N ratio of the light of the second emission peak whose intensity is lower than the intensity of the first emission peak. Even if the fluorescence of the second emission peak is used, it is possible to suppress the deterioration of the image quality of the fluorescent image.

The medical image imaging apparatus according to the second aspect of the present invention acquires an image of a treatment target site during treatment by irradiating a light-sensitive substance accumulated in the treatment target site in a subject with treatment light to generate an image. A medical image imaging device, which is a detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from a light-sensitive substance by irradiating with therapeutic light, and a detection that detects the fluorescence transmitted through the detector filter. It includes a device and an image generator that generates an image based on the output of the detector, fluorescence has at least a first emission peak and a second emission peak, and the wavelength of the first emission peak is the second emission peak. It is a wavelength equal to or less than the wavelength of, and is not included in the wavelength region of the light emitted by the indoor illumination. The wavelength of the second emission peak is a wavelength included in the wavelength region of the light emitted by the indoor illumination, and the predetermined wavelength is wavelength der first emission peak is, the intensity of the first emission peak is higher than the intensity of the second emission peak.

Claims (10)

A medical image imaging device that generates an image by irradiating a light-sensitive substance accumulated in a treatment target site in a subject with treatment light to image the treatment target site during treatment.
A detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from the photosensitive substance by irradiating the therapeutic light.
A detector that detects the fluorescence that has passed through the detector filter, and
It is provided with an image generation unit that generates an image based on the output of the detector.
The fluorescence has at least a first emission peak and a second emission peak.
The wavelength of the first emission peak is a wavelength equal to or less than the wavelength of the second emission peak, and is a wavelength included in the wavelength region of the light emitted by the indoor lighting.
The wavelength of the second emission peak is a wavelength that is not included in the wavelength region of the light emitted by the indoor lighting.
The predetermined wavelength is the wavelength of the second emission peak, which is a medical image imaging device. The medical image imaging device according to claim 1, wherein the detector filter is configured to transmit light having a wavelength longer than the wavelength of the first emission peak, including the predetermined wavelength. The medical image according to claim 1 or 2, wherein the detector filter is configured to transmit light having a wavelength longer than the upper limit wavelength of the wavelength region of the light emitted by the indoor lighting, including the predetermined wavelength. Imaging device. The medical image imaging apparatus according to any one of claims 1 to 3, wherein the intensity of the first emission peak is higher than the intensity of the second emission peak. Any one of claims 1 to 4, wherein the interval between the wavelength of the first emission peak and the wavelength of the second emission peak is larger than the interval between the wavelength of the first emission peak and the peak wavelength of the treatment light. The medical image capturing apparatus according to the section. The medical image imaging apparatus according to any one of claims 1 to 5, wherein the therapeutic light is light having a peak wavelength in a wavelength region of 650 nm or more and 700 nm or less. The wavelength of the first emission peak is included in the region of 700 nm or more and less than 750 nm.
The medical image imaging device according to any one of claims 1 to 6, wherein the wavelength of the second emission peak is included in a region of 750 nm or more and less than 800 nm. A medical image imaging device that generates an image by irradiating a light-sensitive substance accumulated in a treatment target site in a subject with treatment light to image the treatment target site during treatment.
A detector filter that transmits light having at least a predetermined wavelength among the fluorescence emitted from the photosensitive substance by irradiating the therapeutic light.
A detector that detects the fluorescence that has passed through the detector filter, and
It is provided with an image generation unit that generates an image based on the output of the detector.
The fluorescence has at least a first emission peak and a second emission peak.
The wavelength of the first emission peak is a wavelength equal to or less than the wavelength of the second emission peak and is not included in the wavelength region of the light emitted by the indoor lighting.
The wavelength of the second emission peak is a wavelength included in the wavelength region of the light emitted by the indoor lighting.
A medical image imaging device in which the predetermined wavelength is the wavelength of the first emission peak. The medical image imaging device according to claim 8, wherein the detector filter is configured to transmit light having a wavelength shorter than the wavelength of the second emission peak, including the predetermined wavelength. The medical image according to claim 8 or 9, wherein the detector filter is configured to transmit light having a wavelength shorter than the lower limit wavelength of the wavelength region of the light emitted by the indoor lighting, including the predetermined wavelength. Imaging device.

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