WO2016111043A1

WO2016111043A1 - Endoscopic device

Info

Publication number: WO2016111043A1
Application number: PCT/JP2015/075084
Authority: WO
Inventors: 圭久保
Original assignee: オリンパス株式会社
Priority date: 2015-01-07
Filing date: 2015-09-03
Publication date: 2016-07-14
Also published as: JPWO2016111043A1; JP6062111B2

Abstract

This endoscopic device includes: a light source unit for excitation light, which emits excitation light to a subject to which a fluorescent substance having a specific action has been administered; a light source unit for reference light, which emits reference light; a light source unit for action light, which emits action light for causing a specific action; a light source unit for guide light, which emits guide light; an imaging unit which generates an imaging signal; an excitation light cut filter; an information generating unit which generates, from the imaging signal, fluorescence light information, etc., indicating the position of fluorescence light; and an image generating unit which generates an observation image reflecting the position where there is fluorescence light and the position where guide light is emitted.

Description

Endoscope device

The present invention relates to an endoscope apparatus that performs fluorescence observation by irradiating excitation light.

In recent years, endoscope apparatuses have been widely used in the medical field and the like. In addition, there is a method for performing photodynamic diagnosis (PDD) using a photosensitive substance that has a characteristic of being easily accumulated in a lesion site such as a tumor site in a living body and generates fluorescence upon irradiation with excitation light. Are known. A method of performing photodynamic therapy (PDT) on a lesion site diagnosed by PDD is also known.

For example, Japanese Patent Application Laid-Open No. 2008-86680 as a first conventional example discloses an endoscope apparatus including an endoscope for performing treatment by PDT. This endoscope apparatus has a configuration in which an imaging device for normal observation and an imaging device provided with a filter for cutting treatment light are provided. The state of PDT can be observed without generating halation due to the treatment light.
Japanese Patent Application Laid-Open No. 2012-65899 as a second conventional example also discloses an endoscope apparatus for performing treatment by PDT. This endoscope apparatus is administered to the treatment target site for observing the treatment target site, and a treatment light irradiation means for irradiating the treatment light in the subject to treat the treatment target site in the subject. An excitation light irradiating means for irradiating an excitation light that emits fluorescence from a chemical; an imaging means for photoelectrically converting incident light and storing a plurality of pixels that accumulate signal charges according to the amount of incident light; In the first imaging period, which is one of the imaging periods in which the imaging unit captures one image, the therapeutic light irradiation period for irradiating the therapeutic light and the signal charge corresponding to the amount of fluorescence are accumulated. Control means for controlling the treatment light irradiation means and the imaging means so that there is no overlap with the accumulation period.

The first conventional example is an endoscope apparatus that is used by switching between the PDD mode and the PDT mode, and has a defect that does not have a configuration for confirming the irradiation position of the treatment light while observing the fluorescent image. Further, the second conventional example also has a defect that does not include a configuration for confirming the irradiation position of the treatment light.
In addition, there is a treatment method called PIT (Photoimmuno Therapy) in which treatment is performed by setting excitation light and treatment light to the same wavelength. In this treatment method, since the wavelength of the excitation light of the drug (fluorescent substance) and the treatment light for performing phototherapy are the same, the excitation light and the treatment light are images of the observation target imaged by the excitation light cut filter. Therefore, it is difficult to observe the position of the lesion site observed (specified) from the fluorescence image as the fluorescence generation position and the irradiation position of the treatment light at the same time. It was.
The present invention has been made in view of the above points, and provides an endoscope apparatus capable of generating an observation image capable of simultaneously observing the position of a lesion site by a fluorescence image and the irradiation position of treatment light (action light). The purpose is to do.

The endoscope apparatus according to one embodiment of the present invention accumulates in a lesion site, emits fluorescence when irradiated with light having an excitation wavelength, and applies to the tissue when irradiated with light having the excitation wavelength. An excitation light source unit that irradiates a subject to which a fluorescent substance having a specific action is administered with excitation light having the excitation wavelength and generating the fluorescence; and a wavelength different from the excitation wavelength. There is a reference light source unit that irradiates reference light for acquiring the form information of the subject, and the subject is irradiated with light from the excitation light source unit and the reference light source unit A working light source unit that emits working light having the excitation wavelength converged so that the fluorescent substance administered to the subject performs the specific action on a predetermined region of the region; A wave different from the excitation wavelength for the predetermined region. A light source unit for guide light that irradiates the guide light, an imaging unit that receives light from the subject and generates an imaging signal, and light of the excitation wavelength provided between the imaging unit and the subject. An excitation light cut filter that cuts light, and the subject irradiated with light from the excitation light source unit, the reference light source unit, and the guide light source unit are generated by imaging by the imaging unit From the imaging signal, fluorescence information indicating the position of the fluorescence generated from the subject irradiated with the excitation light, shape information of the subject irradiated with the reference light, and guide light in the subject An information generation unit that generates guide light information representing an irradiation position, and the fluorescence generation position and the guide light irradiation position are reflected in the form information of the subject generated in the information generation unit Observation image Having an image generator for forming, the.

FIG. 1 is a diagram showing an overall configuration of an endoscope apparatus according to a first embodiment of the present invention. FIG. 2A is a diagram showing the wavelengths and intensities of excitation light and reference light generated by the excitation light source and reference light source, respectively. FIG. 2B is a diagram showing the wavelengths and intensities of the treatment light and the guide light generated by the treatment light source and the guide light source, respectively. FIG. 2C is a diagram showing transmission characteristics with respect to the wavelength of the excitation light cut filter. FIG. 3 is a flowchart showing the operation content of the first embodiment. FIG. 4 is a diagram illustrating timing for generating excitation light, reference light, guide light, and treatment light in the first embodiment. FIG. 5A shows a fluorescent image. FIG. 5B is a diagram showing a reference light image. FIG. 5C is a diagram showing a superimposed image of a fluorescence image and a reference light image. FIG. 6A is a diagram showing a guide light image. FIG. 6B is a diagram showing a fluorescence image including a guide light image. FIG. 6C is a diagram showing a reference light image including a guide light image. FIG. 6D is a diagram showing a superimposed image (composite image) in which a fluorescence image, a reference light image, and a guide light image are assigned to different colors. FIG. 7 is a diagram illustrating a configuration of a display control circuit that generates a fluorescence image and a reference light image by subtraction processing. FIG. 8A is an operation explanatory diagram showing a fluorescence image and a guide light image in a state where the treatment position and the irradiation position of the guide light do not match. FIG. 8B is an operation explanatory view showing the fluorescence image and the guide light image in a state where the treatment position and the irradiation position of the guide light coincide with each other. FIG. 9 is a diagram illustrating an overall configuration of an endoscope apparatus according to a modified example of the first embodiment. FIG. 10A is a diagram illustrating an example of a configuration of a color filter. FIG. 10B is a diagram illustrating a schematic configuration of a pixel binning unit. FIG. 11 is a diagram illustrating the wavelengths and intensities of the treatment light and the guide light generated by the treatment light source and the guide light source, respectively. FIG. 12 is a flowchart showing a part of the processing contents of the modification.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
As shown in FIG. 1, an endoscope apparatus 1 according to a first embodiment of the present invention includes an endoscope 2 that is inserted into a body cavity, and the endoscope 2 is detachably connected to transmit illumination light or the like. The control device 3 that supplies the signal to the endoscope 2 and performs signal processing on the image pickup unit mounted on the endoscope 2 and the image signal generated by the control device 3 are input, whereby the image pickup unit picks up an image. And a monitor 4 as a display device that displays the image as an observation image.
The endoscope 2 includes an elongated insertion portion 6 to be inserted into a subject 5, an operation portion 7 provided at the rear end (base end) of the insertion portion 6, and a light guide extended from the operation portion 7. A light source connector 8 a at the end of the light guide cable 8 and a signal connector 9 a at the end of the signal cable 9 are detachably connected to the control device 3.
A light guide 11 that transmits (or guides) illumination light is inserted into the insertion portion 6, and the rear end of the light guide 11 reaches the light source connector 8a. Illumination light is incident (supplied) from the light source unit (or light source unit) 12 in the control device 3 to the rear end of the light guide 11. The incident illumination light is transmitted by the light guide 11, from the distal end surface arranged in the illumination window provided at the distal end portion of the insertion portion 6 to the observation site side such as the affected part in the subject 5 facing the distal end surface. Illumination light is spread and irradiated. The light guide 11 transmits incident excitation light for fluorescence observation and reference light for acquiring morphological information of living tissue as illumination light (for acquiring a fluorescent image and a reference light image). To do.

An objective lens 13 is disposed in an observation window provided adjacent to the illumination window, and an optical image of fluorescence emitted from the side irradiated with the excitation light is used as an imaging device of a charge coupled device (abbreviated as CCD) 14. In addition to forming an image on the imaging surface, when the reference light is irradiated, an optical image of the reflected light reflected by the irradiated portion is formed on the imaging surface of the CCD 14. In the present embodiment, a monochrome CCD 14 having no color filter is used as the image sensor.
In the optical path between the objective lens 13 and the imaging surface of the CCD 14, an excitation light cut filter 15 for cutting the excitation light is disposed. Therefore, when the observation part is irradiated with the excitation light and the reference light as described above, the excitation light reflected on the observation part side is cut by the excitation light cut filter 15.
In addition, the endoscope 2 is provided with a treatment instrument insertion port 16 a near the rear end of the insertion portion 6, and the treatment instrument insertion port 16 a is connected to a treatment instrument channel 16 provided along the longitudinal direction of the insertion portion 6. Communicate. In the present embodiment, an optical fiber 17 that guides treatment light by a laser beam for performing treatment is inserted into the treatment instrument channel 16 and extended to the outside of the treatment instrument insertion port 16a. The rear end connector 17 a is detachably connected to the control device 3.

Treatment light generated in the light source unit 12 and guide light for allowing the irradiation position of the treatment light to be visually recognized are incident on the rear end of the optical fiber 17. The treatment light and the guide light are transmitted through the optical fiber 17 and are emitted from the distal end surface of the optical fiber 17 protruding from the distal end opening of the treatment instrument channel 16 to the front side facing the distal end surface with a small beam diameter. The
In this embodiment, as will be described later, in order to confirm the position where treatment light is irradiated (generated), only guide light may be irradiated in a state where treatment light is not irradiated.
In the present embodiment, the excitation light and the treatment light are set in the same wavelength band. Therefore, the reflected light by the treatment light is cut by the excitation light cut filter 15, and the CCD 14 does not generate an image by this reflected light. On the other hand, the wavelength band of the guide light is set to a wavelength band that transmits the excitation light cut filter 15, and the CCD 14 captures an image of the reflected light from the subject side by the guide light. The CCD 14 is subjected to image processing by an image processing unit (or image processing unit) 21 in the control device 3, and the image processing unit 21 outputs the generated image signal to the monitor 4, and the monitor 4 captures an image captured by the CCD 14. indicate. Therefore, in the state in which the treatment light is irradiated, the irradiation position of the treatment light can be confirmed from the image by the guide light displayed on the monitor 4.

In the present embodiment, the input unit includes a light source control unit (or light source control unit) 22 that controls the light source unit 12 and a keyboard or a mouse that inputs instructions to the light source control unit 22 and the image processing unit 21. (Or input unit) 23.
The input unit 23 includes, for example, a data input unit 23a for inputting a treatment position, an automatic control mode (or automatic mode) Ma for automatically performing treatment light irradiation based on an imaging signal, and manually performing treatment light irradiation. It has a mode setting switch SW1 for selecting the manual mode Mm to be performed, and a treatment light switch SW2 for turning on / off the treatment light irradiation. Although FIG. 1 shows an example in which the light source control unit 22 is provided separately from the light source unit 12, the light source unit 12 may include the light source control unit 22.
In this embodiment, after administration of a fluorescent substance that emits fluorescence when irradiated with excitation light of a predetermined wavelength band, which has a characteristic that the subject 5 easily accumulates in a lesion site (or lesion site). , The treatment for treating the lesion site is performed by irradiation with therapeutic light.

Further, in the present embodiment, in order to perform the above-described treatment method using PIT, a fluorescent material having an action of extinguishing a diseased tissue by irradiation with therapeutic light in the same wavelength band as the excitation light is employed as the fluorescent material. For this reason, the treatment light has a function of action light that acts to extinguish the diseased tissue by irradiating the treatment site with the treatment light where the fluorescent substance is accumulated. In other words, the therapeutic light can be considered to form working light.
The light source unit 12 generates excitation light source 24a that generates excitation light in a predetermined wavelength band, reference light source 24b that generates reference light, treatment light source 24c that generates treatment light, and guide light. And a guide light source 24d.
FIG. 2A shows the wavelength band and intensity characteristic Lex of the excitation light generated by the excitation light source 24a, and the wavelength band and intensity characteristic Lre of the reference light generated by the reference light source 24b. In the example shown in FIG. 2A, the wavelength band of the excitation light is set to 600 to 650 nm, and the wavelength band of the reference light is set to, for example, 530 to 550 nm belonging to the green wavelength band. Then, the fluorescent material emits fluorescence in the wavelength band Lfl as shown in FIG. 2C by irradiating the subject 5 to which the fluorescent material is administered with excitation light.

FIG. 2B shows the wavelength band and intensity characteristics Ltr of the treatment light generated by the treatment light source 24c, and the wavelength band and intensity characteristics Lga of the guide light generated by the guide light source 24d. In the example shown in FIG. 2B, the wavelength band of the treatment light is set to 600 to 650 nm that is the same as the wavelength band of the treatment light described above, and the wavelength band of the guide light is set to, for example, 530 to 550 nm belonging to the green wavelength band. Has been.
FIG. 2C shows the transmission characteristic Ft of the excitation light cut filter 15. As shown in FIG. 2C, the excitation light cut filter 15 cuts, for example, 590 to 660 nm including the wavelength band of the excitation light and the wavelength band of the treatment light, and converts the green wavelength band and the fluorescence generated by the fluorescent substance. The characteristic is set to transmit the wavelength band Lfl. In FIG. 2C, the excitation light cut filter 15 is set to have characteristics of transmitting an infrared region exceeding 400 to 590 nm and exceeding 660 to 800.
The CCD 14 has sensitivity not only in the visible band but also in the infrared wavelength band including the fluorescent wavelength band on the long wavelength side of the red wavelength band.

As shown in FIG. 1, the excitation light generated by the excitation light source 24a is reflected by the mirror 25a disposed on the opposing optical path, and the reflected light from the mirror 25a is dichroic mirror disposed on the opposing optical path. The excitation light is selectively reflected by the selective reflection / transmission characteristics corresponding to the wavelength by 25b, and is incident on the rear end face of the light guide 11 through the condenser lens 25c arranged on the optical path of the reflected light.
Further, the reference light generated by the reference light source 24b is incident on the dichroic mirror 25b disposed on the opposite optical path, and the reference light is selectively transmitted by the dichroic mirror 25b and is disposed on the transmitted optical path. Then, it enters the rear end surface of the light guide 11 through the condenser lens 25c. In this embodiment, since a monochrome imaging device is used, the light source control unit 22, as will be described later, the excitation light source 24 a and the reference light source so as to generate the excitation light and the reference light in a surface sequential manner. The light source 24b is controlled so that the observation light in the subject 5 is irradiated with excitation light and reference light in the surface order.
The therapeutic light generated by the therapeutic light source 24c is incident on the dichroic mirror 25d disposed on the opposite optical path, and the therapeutic light is selectively transmitted by the dichroic mirror 25d and is disposed on the transmitted optical path. It is incident on the rear end face of the optical fiber 17.

The guide light generated by the guide light source 24d is reflected by the mirror 25e disposed on the opposing optical path, and the reflected light from the mirror 25e is selectively transmitted by the dichroic mirror 25d disposed on the opposing optical path. And is incident on the rear end face of the optical fiber 17 disposed on the optical path of the reflected light.
On the other hand, the CCD 14 outputs an imaging signal obtained by photoelectric conversion by applying a CCD driving signal generated by the CCD driving circuit 31 in the image processing unit 21. The imaging signal is input to the preprocessing circuit 32 in the image processing unit 21. The preprocessing circuit 32 extracts a signal component in the image pickup signal by an internal correlated double sampling circuit (CDS circuit), and further outputs the image signal to the multiplexer 33 by A / D conversion or the like. The preprocessing circuit 32 in the image processing unit 21 may be defined as performing preprocessing for converting the imaging signal output from the CCD 14 into an image signal in this way, but the signal processing for the imaging signal output from the CCD 14 is performed. It may be defined that the imaging signal is output to the multiplexer 33. Both are formal differences and are substantially the same. In the present specification, description will be made mainly along the former case.
The output terminal of the multiplexer 33 is connected to a memory unit 34 having three frame memories. A fluorescence memory 34a, a reference light memory 34b, and a guide light memory 34c as three frame memories forming the memory unit 34 are connected to the multiplexer 33, and the multiplexer 33 switches the three frame memories in the surface order. As will be described later, in a state where the guide light is not irradiated, the multiplexer 33 switches between the two frame memories in the frame order.
The image signals stored in the three frame memories are input to the display control circuit 35. The display control circuit 35 assigns the fluorescence image, the reference light image, and the guide light image to different colors and superimposes (synthesizes) the observation images. The image signal of the superimposed image is generated and output to the monitor 4. The monitor 4 displays in color the fluorescent image, the reference light image, and the guide light image that are assigned different colors.

The image processing unit 21 includes a fluorescence / guide light processing circuit 36 that performs processing on image signals of the fluorescence image in the fluorescence memory 34a and the guide light image in the guide light memory 34c. Determines whether or not the fluorescence region extraction circuit 36a that extracts the region of the fluorescence image (as the fluorescence region), and whether or not the extracted fluorescence region has a fluorescence luminance (or signal level) Lf that is equal to or greater than a set threshold value. And a determination circuit 36b.
If the determination circuit 36b determines that the fluorescence luminance Lf is greater than or equal to the threshold, the determination circuit 36b sends a determination signal to the light source control unit 22, and the light source control unit 22 causes the guide light source 24d to continuously generate guide light. Control is performed so that the guide light is turned on (see FIG. 4).
When the guide light is generated, the fluorescence / guide light processing circuit 36 performs a process of extracting (acquiring) the guide light irradiation position (guide light position) Pg from the image signal of the guide light. 36c, and the determination circuit 36b is set as the irradiation position Pg of the extracted guide light and the irradiation position of the treatment light manually input from the data input unit 23a (functioning as action light) (as the setting position) (B) A position determination is made as to whether or not the treatment position Pt or the treatment position Pt automatically set by image processing matches from the fluorescence image.

Further, the determination circuit 36b sends a coincidence determination signal when the irradiation position Pg of the guide light coincides with the treatment position Pt (Pg = Pt) to the light source control unit 22, and the light source control unit 22 is controlled by the mode selection switch SW1. When the automatic mode Ma is selected (set), the treatment light source 24c is controlled to generate the treatment light.
On the other hand, when the manual mode Mm is selected, the monitor 4 displays on the monitor 4 that the irradiation position Pg of the guide light and the treatment position Pt coincide with each other, and the endoscope apparatus. The operator as one user is notified by a display that it is in a state suitable for irradiating treatment light.
The image processing unit 21 includes a control circuit 37 that controls the CCD drive circuit 31, the preprocessing circuit 32, the multiplexer 33, the memory unit 34, and the like. The control circuit 37 is connected to the light source control unit 22 and a signal line. It is connected so that a control operation linked to one control can be performed.

For example, in an initial state in which the endoscope apparatus 1 is in an operating state (as will be described later), the light source unit 12 generates excitation light and reference light alternately and does not generate treatment light or guide light. Operates in observation mode. Therefore, in a state of operating in this fluorescence observation mode, the control circuit 37 performs image processing for generating a fluorescence image and a reference light image.
In this case, the control circuit 37 switches the multiplexer 33 between the fluorescence memory 34a as the two frame memories in the memory unit 34 and the reference light memory 34b (a fluorescence image is stored in the fluorescence memory 34a, The reference light image is stored in the reference light memory 34b.
In the fluorescence observation mode, when the fluorescent substance is accumulated in the lesion site and the fluorescence luminance Lf is detected to be equal to or higher than the threshold value, the position confirmation mode is performed in which the irradiation position of the optical fiber 17 is confirmed by irradiating the guide light. After this position confirmation mode, a treatment observation mode for performing treatment by irradiating treatment light is entered. In other words, the position confirmation mode in which the guide light is irradiated can be said to be an intermediate mode between the fluorescence observation mode and the treatment observation mode.

In the position confirmation mode in which the guide light is irradiated, the light source control unit 22 sends a guide light irradiation (ON) signal to the control circuit 37, and the control circuit 37 guides in addition to the fluorescence image and the reference light image. Control is performed so as to perform processing for generating an optical image.
In this position confirmation mode, the control circuit 37 sequentially switches the multiplexer 33 between the fluorescence memory 34a as the three frame memories in the memory unit 34, the reference light memory 34b, and the guide light memory 34c (for fluorescence). The memory 34a stores the fluorescent image, the reference light memory 34b stores the reference light image, and the guide light memory 34c stores the guide light image.
As will be described later, since the fluorescent light image and the reference light image are mixed with the guide light image by irradiation of the guide light, the display control circuit 35, for example, displays the fluorescent image in a state where the guide light image is mixed (or mixed). The reference light image and the reference light image are subtracted from the guide light image acquired or generated in a non-mixed state to generate a non-mixed fluorescent image and a reference light image.
In this position confirmation mode, the guide position extraction circuit 36c extracts the irradiation position Pg of the guide light, sends the extracted position information to the determination circuit 36b, and the determination circuit 36b determines whether or not it matches the treatment position Pt. Determine whether. If the automatic mode Ma is selected, the light source control unit 22 causes the treatment light source 24c to generate the treatment light based on the coincidence determination result by the determination circuit 36b. Control.

On the other hand, when the manual mode Mm is selected, the display control circuit 35 controls to display on the monitor 4 that the matching is performed based on the matching determination result by the determination circuit 36b, and the operator treats the treatment. A treatment light is generated from the light source 24c to notify that it is in a state suitable for treatment. Since the display is performed even in the manual mode Mm, the surgeon can easily perform the timing of irradiating treatment light appropriately.
Even in the state where the treatment light is irradiated, the determination circuit 36b determines whether the irradiation position Pg of the guide light by the guide position extraction circuit 36c exists in the vicinity of the treatment position Pt, and the treatment is performed. When it shifts outside the region set as the vicinity region R (see FIG. 8B) of the position Pt, the generation (irradiation) of the treatment light is stopped via the light source control unit 22. Specifically, when the determination circuit 36b determines that the irradiation position Pg of the guide light does not exist in the vicinity of the treatment position Pt, the determination circuit 36b sends a determination signal of the determination result to the light source control unit 22, and the light source control unit 22 controls the treatment light source 24c to stop the generation (irradiation) of treatment light.
Further, the fluorescence / guide light processing circuit 36 has a memory 36d for storing data such as a threshold value Vth used when the determination circuit 36b determines whether or not the fluorescent image (signal) has a high luminance region Rfh requiring treatment. Have.
In this embodiment, as described in FIG. 4, the excitation light and the reference light are irradiated at different first and second timings (different frame periods in FIG. 4), and both lights are emitted at the third timing. The light source control unit 22 controls to turn off and emit the guide light. Further, the light source control unit 22 performs control so that the guide light is continuously irradiated when the guide light is irradiated at the third timing.

As described above, since the guide light is continuously irradiated, the excitation light, the guide light, and the reference light are also generated even when the first or second timing is periodically reached after the third timing when the guide light is irradiated. The guide light is irradiated at the same time. Further, in the state where the guide light is irradiated, at a timing suitable for irradiating the therapeutic light having the function of action light (automatically based on the result of image processing or manually by the operator) The light source controller 22 controls the treatment light so as to be continuously emitted.
In the case where a monochrome CCD 14 is used, the CCD 14 is in the state where the excitation light, the reference light, the guide light is irradiated as described above, or in the state where the treatment light is further irradiated (the first The first imaging signal corresponding to the fluorescence emitted from the observation site side of the subject 5 and the guide light by the continuous irradiation of the guide light (by the excitation light irradiation at the timing) is output to the image processing unit 21.
Further, the CCD 14 images the second imaging signal corresponding to the reference light emitted from the observation site side of the subject 5 and the guide light by the continuous irradiation of the guide light (by irradiation of the reference light at the second timing). The data is output to the processing unit 21. Further, the CCD 14 outputs a third imaging signal corresponding to the guide light to the image processing unit 21 during the period in which only the guide light or the guide light and the treatment light are irradiated at the third timing.
The third imaging signal is an imaging signal including only guide light, and the first imaging signal including guide light and fluorescence and the second imaging signal including guide light and reference light are input to the image processing unit 21. Then, the image processing unit 21 generates image signals of the fluorescence image, the reference light image, and the guide light image by subtraction image processing.

The endoscope apparatus 1 according to the present embodiment accumulates in a lesion site, emits fluorescence when irradiated with light having an excitation wavelength, and is specified for a living tissue when irradiated with light having the excitation wavelength. An excitation light source 24a that forms an excitation light source unit that irradiates the subject 5 to which the fluorescent substance acting as described above is administered with the excitation light that has the excitation wavelength and generates the fluorescence; A reference light source 24b that forms a reference light source unit that irradiates a reference light for irradiating the reference light for acquiring the morphological information of the subject 5, and a wavelength different from the excitation wavelength; The fluorescent substance administered to the subject 5 converges to perform the specific action on a predetermined region among the regions irradiated with light from the excitation light source unit and the reference light source unit. Treatment light as working light having the excited wavelength A treatment light source 24c that forms a light source for working light to be irradiated, and guide light for irradiating guide light having a wavelength different from the excitation wavelength to the predetermined region (irradiated with the working light) A guide light source 24d that forms a light source unit, a CCD 14 that forms an imaging unit that receives light from the subject 5 and generates an imaging signal, and is provided between the imaging unit and the subject 5. Imaging the subject 5 irradiated with light from the excitation light cut filter 15 that cuts off the light having the excitation wavelength, the excitation light source unit, the reference light source unit, and the guide light source unit Fluorescence information indicating the position of the fluorescence generated from the subject 5 irradiated with the excitation light from the imaging signal generated by imaging by the unit, and configuration information of the subject 5 irradiated with the reference light And the subject 5 An image processing unit 21 that forms an information generation unit that generates guide light information indicating the irradiation position Pg of the guide light, which is the irradiation position of the working light, and the form of the subject 5 generated by the information generation unit And a display control circuit 35 that forms an image generation unit that generates an observation image reflecting the fluorescence generation position and the guide light irradiation position with respect to information.

The image processing unit 21 forming the information generation unit generates fluorescence information indicating the fluorescence position and fluorescence / guide light processing that generates guide light information indicating the irradiation position Pg of the guide light on the subject 5. A circuit 36 is included.
Next, the operation of this embodiment will be described with reference to FIG. FIG. 3 shows a flowchart of a typical processing procedure of the present embodiment. In the present embodiment, a fluorescent substance corresponding to a treatment method for PIT is administered to the subject 5 in advance. After the administration of the fluorescent substance, an observation site such as an affected part in the subject 5 is observed by the endoscope device 1 after a lapse of time to the extent that the fluorescent substance accumulates at the lesion site.
In the first step S1 in FIG. 3, the light source unit 12 generates excitation light and reference light in the order of frames as shown in FIG. 4, and the excitation light and reference light are transmitted by the light guide 11. Excitation light and reference light are spread from the front end surface of the light and irradiated to the observation site side.
In FIG. 4, T represents one frame period. For example, excitation light is irradiated for one frame period T as a first timing, and from the fluorescent substance administered to the subject 5 by irradiation of the excitation light in the one frame period T. The emitted fluorescent image is acquired (captured) by the CCD 14. Further, in the next one frame period T at the second timing when the excitation light is turned off (OFF), the illumination period Tr and reference light shorter than the one frame period T are irradiated. In this way, by irradiating the reference light only for the illumination period Tr shorter than one frame period T, the luminance level of the fluorescent image in the case of imaging with fluorescence and the luminance level of the reference light image acquired by irradiation of the reference light are moderately adjusted. Can be aligned to any level.
Note that the reference light may also be illuminated for one frame period T, and a reference light image with reference light equivalent to the case where the illumination period is substantially shortened may be captured by the electronic shutter by the CCD 14.

As described above, the CCD 14 (which forms the imaging unit) displays a fluorescent image emitted from the observation site side during excitation light irradiation and a reference light image reflected from the observation site side during reference light irradiation. The fluorescent imaging signal and the reference light imaging signal that are sequentially imaged and output in the surface sequential order are output to the image processing unit 21, and the image processing unit 21 outputs the fluorescent imaging signal and the reference light imaging signal in the preprocessing circuit 32. A process of converting into a fluorescence image signal and a reference light image signal is performed. That is, as shown in step S <b> 2 in FIG. 3, the image processing unit 21 (preprocessing circuit 32 thereof) generates a fluorescence image (signal) and a reference light image (signal).
The fluorescence image signal and the reference light image signal are stored in the fluorescence memory 34a and the reference light memory 34b, respectively. The fluorescence memory 34a and the reference light memory 34b function as an R channel image memory and a B channel image memory when an image is displayed in color on the monitor 4. However, when the guide light is further irradiated, there is a case where the two images are stored in a mixed state.
5A and 5B show a fluorescence image If and a reference light image Ir that are captured and generated by the CCD 14.

The fluorescence image signal and the reference light image signal stored in the fluorescence memory 34a and the reference light memory 34b are read out simultaneously, and the display control circuit 35 outputs the fluorescence image signal to the R channel of the monitor 4, and the reference light image. An image signal of a superimposed image obtained by superimposing the fluorescence image and the reference light image is output to the monitor 4 so that the signal is output to the B channel of the monitor 4.
As shown in step S3 in FIG. 3, the monitor 4 displays a superimposed image in which the fluorescent image If and the reference light image Ir are assigned to different colors and superimposed (combined) as shown in FIG. 5C. In the superimposed image displayed in FIG. 5C, the fluorescent image If portion is displayed in red, and the reference light image Ir portion is displayed in blue.
Further, the operator sets the automatic mode Ma and the manual mode Mm by operating the mode selection switch SW1) of the input unit 23 as shown in step S4.
In addition, as shown in step S <b> 5, the surgeon manually designates the treatment position Pt from the data input unit 23 a of the input unit 23 with reference to the fluorescence image in the superimposed image displayed on the monitor 4. As described later, the treatment position Pt may be automatically set (or detected) from the guide light image by image processing without performing manual designation. The fluorescence / guide light processing circuit 36 uses the fluorescence / guide light to transmit the mode information set from the input unit 23 and the information on the manually designated treatment position Pt (this information is not input in the automatic mode Ma). The data is stored in the memory 36d in the processing circuit 36.

In the next step S6, the fluorescence region extraction circuit 36a in the fluorescence / guide light processing circuit 36 has a brightness level greater than 0 level (or a predetermined value set greater than 0) from the fluorescence image (signal) stored in the fluorescence memory 34a. The region Rf of the fluorescence image that is equal to or greater than the threshold value is extracted. The fluorescence region extraction circuit 36a sends the fluorescence image (signal) of the extracted region Rf of the fluorescence image to the determination circuit 36b.
When the treatment position Pt is not manually specified, the fluorescence region extraction circuit 36a has a function of extracting the region Rf of the fluorescence image, and a high brightness region in the fluorescence image that is equal to or greater than the threshold Vth from the region Rf of the extracted fluorescence image. It has the function of determining the presence or absence of Rfh and further setting the position of the luminance center of gravity of the high luminance region Rfh as the treatment position Pt. That is, in the present embodiment, the treatment position Pt can be designated manually or the treatment position Pt can be set by image processing.
In the next step S7, the determination circuit 36b sets in advance whether or not the fluorescent image (signal) has a high luminance region Rfh (abbreviated as region Rfh above Vth in FIG. 3) that is equal to or higher than a threshold Vth that requires treatment. It is determined by comparing with the threshold value Vth. Note that the threshold value Vth is set in advance from the fluorescence luminance when the fluorescent substance is accumulated at the lesion site requiring treatment. The threshold value Vth is stored in the memory 36d from the data input unit 23a, for example.

If the high brightness area Rfh equal to or higher than the threshold value Vth is not detected in step S7, the process returns to step S6. If the high brightness area Rfh equal to or higher than the threshold value Vth is detected, the process proceeds to step S8.
In step S8, the determination circuit 36b sends the determination result to the light source control unit 22, and the light source control unit 22 controls the guide light source 24d to continuously generate the guide light. FIG. 4 shows how the guide light source 24d continuously generates guide light after time tg. The optical fiber 17 transmits guide light and emits the guide light from the distal end surface of the optical fiber 17 toward the observation site.

The optical fiber 17 continuously emits the guide light incident on the optical fiber 17 toward the observation site in a state where the light beam is converged without spreading from the tip surface (as shown in FIG. 1). When the determination circuit 36b determines that the high brightness area Rfh equal to or higher than the threshold Vth is no longer detected after the guide light is irradiated, the determination signal is sent to the light source control unit 22 to control the light source. The unit 22 may control the guide light source 24d to stop generating the guide light. In this case, the light source control unit 22 controls to stop the generation of the treatment light.
When the guide light is continuously emitted as described above, the light source control unit 22 generates (irradiates) only the guide light from the state where the excitation light and the reference light are alternately generated as shown in FIG. The light emission is controlled so as to generate a frame period that is an irradiation period corresponding to timing 3.
In the present embodiment, when the high brightness area Rfh equal to or higher than the threshold value Vth is detected, the guide light is emitted in step S8 even in the manual mode Mm. However, in the manual mode Mm, The monitor 4 may display that the high-luminance region Rfh equal to or higher than the threshold value Vth has been detected, and the operator may be prompted to perform an operation of emitting guide light from the input unit 23.

The light source control unit 22 sends a signal generated by continuously generating guide light to the control circuit 37 of the image processing unit 21, and the control circuit 37 multiplexes the guide light image captured in a state where only the guide light is irradiated. The light is stored in the guide light memory 34 c via the line 33. FIG. 6A shows a guide light image Ig stored in the guide light memory 34c.
The guide light memory 34c has a function of an image memory that outputs to the G channel in the R, G, and B channels when the monitor 4 displays a color image.
In the guide light image Ig shown in FIG. 6A, for example, a circle on the center side is a portion where therapeutic light is transmitted and irradiated from the tip of the optical fiber 17 (in the guide light image, for example, black (the signal level is 0)). The circular ring outside the circle is a guide light portion, and is detected as a portion having a high green pixel value. In the case of FIG. 6A, the center of the ring is the treatment light irradiation position. The portion for transmitting the treatment light in FIG. 6A may be shared, and the guide light may be transmitted.
When the guide light is continuously irradiated, the image stored in the fluorescence memory 34a is an image If + Ig in which the fluorescence image If and the guide light image Ig are mixed as shown in FIG. 6B, and the reference light memory 34b. The image stored in is an image Ir + Ig in which the reference light image Ir and the guide light image Ig are mixed as shown in FIG. 6C.

In the next step S9 (shown in FIG. 3), the display control circuit 35 performs a subtraction process as shown in FIG. 7 to generate the fluorescence image If, the reference light image Ir, and the guide light image Ig as different color signals, Different color signals are output to the R, B, and G channels of the monitor 4, respectively.
As shown in FIG. 7, the subtraction processing circuit 35a in the display control circuit 35 is connected to the adjacent one from the fluorescence image If and the guide light image Ig acquired (simultaneously) in one frame period T stored in the fluorescence memory 34a. A fluorescence image is extracted by performing a process of subtracting the guide light image Ig acquired in the frame period T and stored in the guide light memory 34 c, and is output to the R channel of the monitor 4.
In addition, the subtraction processing circuit 35b of the display control circuit 35 uses the adjacent one frame period T from the reference light image Ir and the guide light image Ig acquired (simultaneously) in the one frame period T stored in the reference light memory 34b. The guide light image Ig acquired in step S1 and stored in the guide light memory 34c is subtracted to extract the reference light image Ir and output it to the B channel of the monitor 4. In addition, the display control circuit 35 outputs the guide light image Ig stored in the guide light memory 34 c to the G channel of the monitor 4.

In the case where the brightness of the image captured by the CCD 14 and displayed on the monitor 4 is adjusted to a brightness that can be easily diagnosed by the electronic shutter, the subtraction process described above is performed in the imaging period ( Processing that considers the electronic shutter value) may be performed. That is, the subtraction processing circuit 35a is independently acquired in the fluorescence image If and the guide light image Ig (If + Ig input to the subtraction processing circuit 35a in FIG. 7) acquired simultaneously before the subtraction processing, and in the adjacent frame period. Further, a process of correcting the luminance value of the guide light image Ig may be performed. Specifically, when the luminance level of each frame period is adjusted by the electronic shutter of the CCD 14, it is acquired independently in the adjacent frame period with respect to the electronic shutter value of the frame period in which the fluorescent image If and the guide light image Ig are acquired simultaneously. When the electronic shutter value of the guide light image Ig is a constant α, the subtraction processing circuit 35a performs a process of correcting the luminance value of each pixel of the guide light image Ig in the adjacent frame period to 1 / α before the subtraction process. . Then, after performing the correction process, subtraction is performed. Thus, by adjusting the brightness of the guide light image before subtraction, the fluorescence image If can be extracted with higher accuracy than when the electronic shutter is used.
Similarly to the description of the subtraction processing circuit 35a, the subtraction processing circuit 35b receives the reference light image Ir and the guide light image Ig acquired simultaneously before the subtraction processing (input to the subtraction processing circuit 35b in FIG. 7). Ir + Ig) and the luminance value of the guide light image Ig acquired independently in the adjacent frame period may be corrected based on the adjustment value of the luminance level (for example, the electronic shutter value by the CCD 14).

As shown in FIG. 6D, the monitor 4 displays a color image as an image If + Ir + Ig superimposed (synthesized) in a state where the three images are assigned to different colors. More specifically, the image If + Ir + Ig is an image If (R) + Ir (B) + Ig (G). Here, Ii (J) represents that the image Ii (i = f, r, g) is displayed in J (J = R, B, G) color.
By observing the image If + Ir + Ig in FIG. 6D, the operator can confirm the extent of the lesion from the fluorescence image If (R) (in other words, from the fluorescence image in which the fluorescent substance is generated at the lesion site), and the guide light image From this position, it is possible to confirm the position where the treatment light is irradiated, and it is easy to perform an operation of setting the position of the guide light image Ig (G) to the position of the lesion site in the fluorescence image.
In the next step S10, the guide position extraction circuit 36c in the fluorescence / guide light processing circuit 36 extracts the center position of the guide light image from the guide light image stored in the guide light memory 34c as the guide light irradiation position Pg. And sent to the determination circuit 36b.
In the next step S11, the determination circuit 36b determines whether or not the irradiation position Pg of the guide light matches the treatment position Pt.
8A and 8B are explanatory diagrams of the determination operation by the determination circuit 36b. In the state of the fluorescence image If shown in FIG. 5A and the state of the guide light image Ig shown in FIG. 6A, for example, the treatment position Pt and the irradiation position Pg of the guide light set manually or by image processing with respect to the fluorescence image If Is different. FIG. 8A shows a state where the treatment position Pt (Xf, Yf) set from the fluorescence image If and the irradiation position Pg (Xg, Yg) of the guide light are different. Pt (Xf, Yf) and Pg (Xg, Yg) represent two-dimensional positions on the XY coordinate system (X, Y) at the treatment position Pt and the irradiation position Pg in the fluorescence image If and the guide light image Ig. 8A and 8B indicate a dark image portion where the signal level (pixel value) is almost zero.

On the other hand, the surgeon moves the irradiation position Pg (Xg, Yg) of the guide light in the state of FIG. 8A to the treatment position Pt (Xf, Yf), and as shown in FIG. 8B, the treatment position Pt (Xf, Yf). ) And the irradiation position Pg (Xg, Yg) of the guide light match, the determination circuit 36b determines that they match.
If it is determined in step S11 that the treatment position Pt does not match the irradiation position Pg of the guide light, the process returns to step S10.
On the other hand, if the determination result indicates that the treatment position Pt matches the guide light irradiation position Pg, the process proceeds to step S12.
In the next step S12, the determination circuit 36b determines whether or not the automatic mode Ma is currently selected. If the determination result indicates that the automatic mode Ma is selected, in the next step S13, the determination circuit 36b sends a signal for causing the light source control unit 22 to generate treatment light.
The light source control unit 22 controls the therapeutic light source 24c to generate therapeutic light, and the therapeutic light source 24c continuously generates therapeutic light. The therapeutic light generated by the therapeutic light source 24c is transmitted by the optical fiber 17 that transmits the guide light, and the therapeutic light is irradiated to the position where the guide light is irradiated. In addition, the position where the guide light is irradiated and the position where the treatment light is irradiated are usually narrow spots. In other words, the treatment light is irradiated to the treatment position Pt in a converged state.

FIG. 4 shows a state where the treatment light source 24c continuously generates treatment light after the time tt. The treatment light is light in the same wavelength band as the excitation light and is cut by the excitation light cut filter 15 and thus does not affect the imaging by the CCD 14.
In the state where the treatment light is irradiated, the determination circuit 36b monitors the irradiation position Pg of the guide light extracted by the guide position extraction circuit 36c as shown in step S14.
In the next step S15, the determination circuit 36b determines whether or not the irradiation position Pg of the guide light exists within the vicinity region R of the treatment position Pt. The neighboring region R including the treatment position Pt is indicated by a dotted line in FIG. 8B. This neighboring region R may be set manually by the operator from the input unit 23, or a range whose luminance level is slightly lower than the treatment position Pt is set as the neighboring region R by image processing (by the fluorescence region extracting circuit 36a). Alternatively, it may be set as a region close to the same point as the treatment position Pt (set as if the irradiation position Pg substantially coincides with the treatment position Pt).
In step S15, when the determination result indicates that the irradiation position Pg of the guide light does not exist within the vicinity region R of the treatment position Pt, the determination circuit 36b sends the determination signal to the light source control unit 22.

In the next step S16, the light source control unit 22 controls the treatment light source 24c so that it does not generate treatment light. That is, the treatment light is turned off, and the process returns to step S10. On the other hand, if the determination result indicates that the irradiation position Pg of the guide light is within the region R near the treatment position Pt, the process proceeds to step S17. In this step S17, for example, the control circuit 37 (or determination circuit 36b) determines whether or not a predetermined irradiation time ts has elapsed from the start of treatment light irradiation, and if the predetermined irradiation time has not elapsed. The process returns to step S14. On the other hand, in the case of a determination result in which a predetermined irradiation time ts has elapsed since the start of treatment light irradiation, the light source control unit 22 turns off the treatment light in the next step S18 and ends the processing of FIG. .
The control circuit 37 (or the determination circuit 36b) measures the time so as to integrate the time during which the treatment light is actually irradiated from the start of the treatment light irradiation, and the measured time is set to a predetermined value set in advance. It is determined whether or not the irradiation time ts has been reached.
If the manual mode Mm is set instead of the automatic mode Ma in the determination process of step S12, the determination circuit 36b in step S19 indicates that the treatment position Pt and the irradiation position Pg of the guide light match. Is sent to the display control circuit 35. The display control circuit 35 generates character information for displaying that the treatment position Pt and the irradiation position Pg of the guide light coincide with each other and is suitable for irradiating treatment light, and displays the character information on the monitor 4.

The surgeon can grasp the timing of operating the treatment light switch SW2 by displaying that the state is suitable for irradiating treatment light.
In the next step S20, the light source control unit 22 determines whether or not the treatment light irradiation operation has been performed by the treatment light switch SW2, and waits for the operation.
When the treatment light irradiation operation is performed in step S20 (by the treatment light switch SW2), in the next step S21, the light source control unit 22 applies the treatment light source 24c to the treatment light source 24c as in the case of step S13. The treatment light is controlled to be generated, and the treatment light source 24c continuously generates the treatment light. The therapeutic light generated by the therapeutic light source 24c is transmitted by the optical fiber 17 that transmits the guide light, and the therapeutic light is irradiated to the position where the guide light is irradiated.
In the next step S22, the determination circuit 36b monitors the irradiation position Pg of the guide light extracted by the guide position extraction circuit 36c as in the case of step S14.
Then, in the next step S23, the determination circuit 36b determines whether or not the irradiation position Pg of the guide light exists within the vicinity region R of the treatment position Pt as in the case of step S15.

In step S23, when the determination result indicates that the irradiation position Pg of the guide light does not exist within the vicinity region R of the treatment position Pt, the determination circuit 36b sends the determination signal to the light source control unit 22 as in step S15. Send to.
In the next step S24, the determination circuit 36b controls the light source control unit 22 so that the treatment light source 24c does not generate treatment light, as in step S16. The adult treatment light is turned off and the process returns to step S10.
On the other hand, if the determination result indicates that the irradiation position Pg of the guide light is within the vicinity region R of the treatment position Pt, the process proceeds to step S25 as in step S17. In step S25, for example, the control circuit 37 ( Alternatively, the determination circuit 36b) determines whether or not the predetermined irradiation time ts has elapsed from the start of treatment light irradiation, and when the predetermined irradiation time ts has not elapsed, the process returns to the process of step S22.
On the other hand, in the case of the determination result that the predetermined irradiation time ts has elapsed from the start of the treatment light irradiation, in the next step S26, the display control circuit 35 uses the monitor 4 to indicate that the predetermined irradiation time ts has elapsed. In step S27, the light source control unit 22 waits for an operation to turn off the treatment light.

The surgeon operates the therapeutic light switch SW2 to turn off the therapeutic light when ending the treatment with reference to the display indicating that the predetermined irradiation time ts has elapsed. When an operation for turning off the treatment light is performed, the light source control unit 22 turns off the treatment light as shown in step S17 and ends the processing of FIG.
According to the first embodiment operating in this manner, a fluorescence image representing the position of a lesion site due to fluorescence and a treatment position Pt as a treatment light irradiation position (by display of the irradiation position Pg of guide light) are simultaneously provided. Since an observation image that can be confirmed is generated, it is possible to easily perform treatment treatment by irradiation with therapeutic light.
In addition, when the treatment light is irradiated to a position deviating from the treatment position Pt, the irradiation of the treatment light can be automatically stopped and the irradiation time of the treatment light irradiated to the lesion site can be accurately measured. Therefore, the treatment light irradiation time can be managed with high accuracy.
In addition, since a guide light is automatically irradiated when a fluorescence brightness Lf equal to or higher than the threshold value Vth is detected in the fluorescence image, the operator can easily confirm the position of the lesion site. Further, when the automatic mode Ma is set, when the irradiation position Pg of the guide light coincides with the treatment position Pt, the treatment light irradiation timing can be set without delay in order to set the treatment light irradiation state. Treatment can be performed in a short time and the burden on the operator can be reduced.

In the first embodiment described above, the endoscope apparatus 1 in the case of using a monochrome imaging device has been described. However, as in the modification shown in FIG. 9, the CCD 14 as an imaging device including the color filter 41 is provided. It is also possible to use the endoscope apparatus 1B.
FIG. 10A shows an example of the color filter 41 provided on the imaging surface of the monochrome CCD 14. The color filter 41 is, for example, an R, G, B stripe filter (simply abbreviated as R, G, B filter) 42R, which transmits R, G, B light on the pixels of the horizontal line on the imaging surface of the CCD 14. 42G and 42B are periodically arranged in the vertical direction. The R filter 42R has a characteristic of transmitting fluorescence in the infrared wavelength band in addition to R.
In this modification, excitation light, reference light (see FIG. 2A), and treatment light (see FIG. 2B) generate light having the same wavelength band as that of the first embodiment. On the other hand, the guide light is set to a blue wavelength band characteristic Lga as shown in FIG. 11 (note that it has a narrower band characteristic than the wavelength band shown in FIG. 11 as shown in FIG. 2B). Is also good). In FIG. 11, the characteristic Ltr of the wavelength band of the treatment light is also shown. In addition, the fluorescent material generates fluorescence in the same infrared wavelength band as in the first embodiment, and the excitation light cut filter 15 has the same transmission characteristics as in the first embodiment.

In the case of this modification, the fluorescence, reference light, and guide light are color-separated (optically) by R, G, B filters 42R, 42G, 42B, respectively, and each pixel 43 (see FIG. 10A). In this case, the pixels 43 that image the light that has passed through the R, G, B filters 42R, 42G, and 42B respectively serve as fluorescence pixels, reference light pixels, and guide light pixels that are sensitive to fluorescence, reference light, and guide light. Has function.

For this reason, in this modification, the light source control unit 22 controls the light source unit 12 to generate excitation light, reference light, guide light, and treatment light as continuous light. When the intensity of the reference light is too high, as shown in FIG. 4, pulse emission is performed in the illumination period Tr smaller than the frame period T in each frame period T, or continuous emission is performed at a reduced emission intensity. You can do that.
In the image processing unit 21B according to this modification, the CCD 14 to which the CCD driving signal is applied by the CCD driving circuit 31 outputs a simultaneous color imaging signal for one frame, and the color imaging signal is a preprocessing circuit. 32 '. The pre-processing circuit 32 in FIG. 1 performs pre-processing on the frame-sequential imaging signal. However, the pre-processing circuit 32 ′ in this modification image is transmitted through the R, G, B filters 42R, 42G, 42B. Pre-processing is performed on the R, G, and B imaging signals.
In the present modification, for example, a pixel binning unit (or pixel binning) that performs pixel binning (pixel addition) as illustrated in FIG. 10B with respect to an imaging signal (R imaging signal) of a fluorescent pixel that has passed through the R filter 42R. Circuit) 45.

The shift register 46 in the CCD 14 normally outputs a pixel signal (imaging signal) for each pixel from the output terminal on the right end via the adder circuit 47, but the timing for outputting the pixel signal of R pixels for one line in the horizontal direction. The CCD driving circuit 31 sends a control signal for pixel addition (pixel addition) to the addition circuit 47. The addition circuit 47 to which the control signal (for pixel addition) is applied adds pixel signals for, for example, three pixels from the right end of the shift register 46 and outputs the addition signal from the output end of the CCD 14.
In this case, an addition signal obtained by adding three pixels adjacent in the horizontal direction is output. Note that a signal indicating the number of pixels to be added in the case of pixel binning from the CCD drive circuit 31 is also sent to the addition circuit 47, and the addition circuit 47 adds the added signals for any plural pixels within the number of pixels that can be added. May be output.
The present invention is not limited to the configuration in which pixel binning is performed in the CCD 14 shown in FIG. 10B. For example, an addition signal obtained by adding a plurality of pixels adjacent in the horizontal direction in the R imaging signal is generated in the preprocessing circuit 32 ′. Anyway.

In the present modification, the multiplexer 33 ′ is switched according to the arrangement of the R, G, and B filters in the color filter 41. Specifically, when the R image signal obtained by extracting the signal component from the R imaging signal of the fluorescent pixel that has passed through the R filter is output (timing) from the preprocessing circuit 32 ′, the multiplexer 33 ′ The memory 34a is selected, and the R image signal is stored in the fluorescence memory 34a.
Similarly, when the G image signal obtained by extracting the signal component from the G imaging signal of the reference light pixel that has captured the reference light that has passed through the G filter is output from the preprocessing circuit 32 ′ (timing), the multiplexer 33 ′. Selects the reference light memory 34b, and the G image signal is stored in the reference light memory 34b.
Similarly, when the B image signal obtained by extracting the signal component from the B imaging signal of the guide light pixel obtained by imaging the guide light transmitted through the B filter is output from the preprocessing circuit 32 '(timing), the multiplexer 33' Selects the guide light memory 34c, and the B image signal is stored in the guide light memory 34c.

Note that, for example, as described in the first embodiment, the multiplexer 33 ′ uses the guide light memory at the timing of the B image signal even when the excitation light and the reference light are generated and the guide light is not generated. 34c is selected.
In addition to the function of outputting the image signal from the memory unit 34 to the monitor 4 as it is, the display control circuit 35 ′ in this modification has character information display control corresponding to the fluorescence / guide light processing circuit 36 (FIG. 3). Steps S19 and S26) are performed. Other configurations are the same as those in the first embodiment.
The operation of this modification is almost the same as that of the first embodiment shown in FIG. Only the different parts will be described below.
As shown in FIG. 12, in the first step S <b> 31, the light source unit 12 generates excitation light and reference light as continuous light, and the excitation light and reference light are transmitted by the light guide 11 and from the front end surface of the light guide 11. Excitation light and reference light are spread and irradiated on the observation site side.

In the present modification, the fluorescence emitted from the observation site side is in the infrared band, so this fluorescence passes through the R filter 43R and is received by the R pixel. Further, the light reflected on the observation site side by the irradiation of the reference light passes through the G filter 43G and is received by the G pixel.
In this modification, the R imaging signal is output from the CCD 14 as a fluorescence imaging signal, which is an addition signal obtained by adding a plurality of pixels by the pixel binning unit 45.
That is, in step S32 subsequent to step S31, the pixel binning unit 45 performs pixel binning for adding a plurality of pixels to the fluorescent imaging pixel, and outputs the added R imaging signal.
The R image signal of the added R pixel and the G image signal of the G pixel are extracted as signal components in the pre-processing circuit 32 ′ to become an R image signal and a G image signal. That is, as shown in step S2 of FIG. 3, the image processing unit 21 ′ generates a fluorescence image (signal) and a reference light image (signal) in the preprocessing circuit 32 ′.

The R image signal and the G image signal are respectively stored in the fluorescence memory 34a and the reference light memory 34b via a multiplexer 33 'that is switched in accordance with the arrangement of the R, G, B filters 42R, 42G, 42B within one frame period. Is done.
Since step S3 and subsequent steps are substantially the same as the steps after step S3 shown in FIG. 3, the description thereof is omitted. However, the processing after step S3 in FIG. 3 is processing when a monochrome imaging device is used, and in this modification, specific processing contents in each step by using the imaging device including the color filter 41 are used. There may be discrepancies.
For example, in the state in which the excitation light and the reference light are irradiated and the fluorescence image and the reference light image are displayed on the monitor, as shown in step S8, the guide light is further irradiated in the first embodiment. In this modification, a period during which the guide light image is mixed with the fluorescence image has occurred. However, in this modification, the color filter 41 separates the images and images are captured in the three frame memories. Images, reference light images, and guide light images can be stored separately. Therefore, the fluorescence image, the reference light image, and the guide light image can be displayed in different colors on the monitor 4 without performing a subtraction process for separation in the display control circuit 35.
Further, in this modification, the R pixel signal that has passed through the R filter 42R is output as, for example, a plurality of pixels adjacent in the horizontal direction and an added sum signal, so that the signal level of the fluorescence with low signal intensity is greatly increased. Can be increased. In addition, since the same added signal is output in a plurality of added pixels, the resolution in the horizontal direction is lowered as compared with the case where the addition is not performed.

According to this modification, the same effect as that of the first embodiment is obtained. In addition, in this modification, when fluorescence is imaged, a plurality of adjacent pixels that capture fluorescence are added, so that an observation image in which a fluorescent image with low signal intensity is easily visible can be generated. Can do.
Note that embodiments configured by combining a part of the above-described modifications and embodiments also belong to the present invention. Further, the pixel addition described in the above modification may be applied to the first embodiment. In that case, pixel addition may be performed every frame period in which fluorescence is imaged. However, it is necessary to remove the image portion of the guide light in the frame where the irradiation of the excitation light (fluorescence imaging) and the irradiation of the guide light overlap. For this reason, in each frame period during which the excitation light is irradiated, for example, the light source control unit 22 turns on / off the guide light irradiation so that the irradiation of the guide light is stopped (along with the reference light) and the image can be captured only by the fluorescence. May be controlled. Further, when the treatment light is irradiated together with the guide light, the treatment light may be turned off simultaneously when the irradiation of the guide light is turned off.
In the modification and the embodiment described above, a region Rf having a fluorescence luminance equal to or higher than a threshold value exceeding 0 level is extracted from the fluorescence image, a high luminance region Rfh is determined from the region Rf, and the high luminance region Rfh is determined. Although the case where the position such as the luminance center of gravity is set as the treatment position Pt has been described, the treatment position Pt may be set at an arbitrary position within the region Rf.
3 and FIG. 12, the excitation light, reference light, guide light, and treatment light are not limited to ON / OFF, and excitation is performed at an arbitrary timing according to the judgment of the operator. It is also possible to turn on / off irradiation of light, reference light, guide light, and treatment light. Moreover, although the case where guide light and treatment light are continuously irradiated has been described, the light may be irradiated intermittently.

This application is filed on the basis of the priority claim of Japanese Patent Application No. 2015-001786 filed in Japan on January 7, 2015, and the above disclosure is disclosed in the present specification, claims, It shall be cited in the drawing.

Claims

Fluorescence is emitted when irradiated with light having an excitation wavelength and accumulated at a lesion site, and is administered with a fluorescent substance having a specific action on living tissue when irradiated with light having the excitation wavelength. A light source unit for excitation light that irradiates the specimen with excitation light for generating the fluorescence having the excitation wavelength;
A light source unit for reference light, which is a wavelength different from the excitation wavelength, and irradiates a reference light for acquiring morphological information of the subject;
The fluorescent substance administered to the subject with respect to a predetermined region of the region irradiated with light from the excitation light source unit and the reference light source unit to the subject A working light source for irradiating with working light having the excitation wavelength converged to act;
A light source unit for guide light that irradiates guide light having a wavelength different from the excitation wavelength with respect to the predetermined region;
An imaging unit that receives light from the subject and generates an imaging signal;
An excitation light cut filter that is provided between the imaging unit and the subject and cuts light of the excitation wavelength;
The excitation light is generated from the imaging signal generated by the imaging unit imaging the subject irradiated with light from the excitation light source unit, the reference light source unit, and the guide light source unit. Fluorescence information indicating the position of the fluorescence generated from the irradiated subject, shape information of the subject irradiated with the reference light, and guide light information indicating the irradiation position of the guide light on the subject. An information generator to generate;
An image generation unit that generates an observation image reflecting the fluorescence generation position and the guide light irradiation position with respect to the form information of the subject generated in the information generation unit;
An endoscope apparatus characterized by comprising:
Further, based on the fluorescence imaging signal, the fluorescence generation position set in a region having a fluorescence luminance equal to or higher than a first threshold in the subject, and the guide light imaging signal based on the guide light imaging signal. A determination unit for determining whether the irradiation position matches,
When the determination unit determines that the generation position of the fluorescence and the irradiation position of the guide light coincide with each other, the action light is emitted, and when it is determined that the irradiation position does not match, the action A light source control unit that controls the light source unit for working light so as not to emit light;
The endoscope apparatus according to claim 1, further comprising:
The excitation light is irradiated at a first timing, the reference light is irradiated at a second timing different from the first timing, and a third timing different from the first timing and the second timing. The excitation light source unit and the reference light source unit are controlled so as to be turned off, and the guide light is emitted at the first timing, the second timing, and the third timing. A light source control unit that controls the light source unit for guide light and further controls the light source unit for working light so as to irradiate the working light at a fourth timing after the third timing,
The imaging unit is a monochrome imaging device and corresponds to the fluorescence and the guide light from the subject irradiated with the excitation light, the action light, and the guide light at the first timing. And the second imaging signal corresponding to the reference light and the guide light is generated from the subject irradiated with the reference light, the action light, and the guide light at the second timing. And generating a guide light imaging signal representing the irradiation position of the guide light on the subject from the subject irradiated with the guide light after the third timing,
The information generation unit generates a fluorescence image signal from the first imaging signal and the third imaging signal as the fluorescence information, and the second imaging signal and the third imaging signal as the reference light information. The reference light image signal is generated, and the fluorescence image signal, the reference light image signal, and the guide light image signal corresponding to the guide light imaging signal are assigned to different colors, respectively, for the morphological information of the subject. The endoscope apparatus according to claim 1, wherein an image reflecting the generation position of the fluorescence and the irradiation position of the guide light is generated.
A light source control unit that controls the fluorescence observation light source unit and the working light source unit so as to form an irradiation period in which the excitation light, the reference light, the working light, and the guide light are irradiated simultaneously; Have
The imaging unit includes a fluorescent pixel having sensitivity to the excitation wavelength and the fluorescence wavelength, a reference light pixel having sensitivity to the wavelength of the reference light, and a guide light pixel having sensitivity to the wavelength of the guide light. And receiving the fluorescence passing through the excitation light cut filter out of the light from the subject in the fluorescence pixel to generate the fluorescence imaging signal, and the light out of the subject in the reference light pixel Receiving the reflected light of the reference light to generate the reference light imaging signal, and receiving the reflected light of the guide light among the light from the subject in the guide light pixel to generate the guide light imaging signal. The endoscope apparatus according to claim 1.
The determination unit further determines the presence / absence of a fluorescent image region having a fluorescent luminance equal to or higher than a second threshold based on the fluorescent imaging signal,
3. The endoscopy according to claim 2, wherein in the case of the determination result that the fluorescent image area exists, the light source control unit controls the guide light source unit to emit the guide light. Mirror device.
A determination unit for determining the presence / absence of a fluorescent image region having a fluorescent luminance equal to or higher than a second threshold based on the fluorescent imaging signal;
A light source control unit that controls the light source unit for guide light to irradiate the guide light, with the timing of the determination result that the fluorescence image area equal to or greater than the second threshold is present as the third timing; Have
Furthermore, after the third timing, the irradiation position of the guide light extracted from the guide light image signal coincides with a set position set as an irradiation position for irradiating the working light in the fluorescent image area. Then, with the timing of the determination result determined by the determination unit as the fourth timing, the light source control unit controls the working light source unit to irradiate the working light. Item 5. The endoscope apparatus according to Item 3.
And a determination unit for determining the presence or absence of a fluorescent image region having a fluorescent luminance equal to or higher than a second threshold based on the fluorescent imaging signal,
In the case where the determination result is a determination result that there is an image area of fluorescence equal to or greater than the second threshold, the light emission control unit further includes a first irradiation period in which the excitation light and the reference light are simultaneously irradiated. The guide light source unit controls the guide light so as to be in a second irradiation period that is simultaneous with the irradiation of the excitation light and the reference light,
Furthermore, in the second irradiation period, in the case of a determination result determined by the determination unit to coincide with a set position set as an irradiation position for irradiating the action light in the fluorescence image area, the light emission control unit The working light source unit controls the working light to irradiate the working light so as to form the irradiation period that is simultaneous with the irradiation of the excitation light, the reference light, and the guide light. The endoscope apparatus according to claim 4, wherein the endoscope apparatus is characterized.
The image processing apparatus further comprises a pixel binning circuit that outputs a pixel addition signal obtained by adding a plurality of adjacent fluorescent pixels when the fluorescent imaging signal is output from each of the fluorescent pixels as the fluorescent imaging signal. 4. The endoscope apparatus according to 4.
The image processing apparatus further comprises a pixel binning circuit that outputs a pixel addition signal obtained by adding a plurality of adjacent fluorescent pixels when the fluorescent imaging signal is output from each of the fluorescent pixels as the fluorescent imaging signal. The endoscope apparatus according to 7.