JPH09154812A - Optical diagnostic device - Google Patents

Abstract

It is an object of the present invention to provide an optical diagnostic apparatus that simplifies the configuration of the apparatus and at the same time can use an image sensor for both lesion observation and fluorescence observation. A laser light source for excitation that continuously generates a light beam having an excitation wavelength, a white light source that intermittently emits white light for observing a lesion, and an excitation light reflected from the lesion. A bandpass filter 4 for separating excitation light and light of other wavelengths from fluorescence and white light, and an image pickup device 5 for capturing an optical image from a lesion part where the excitation light is removed by the bandpass filter 4, A control device 10 that controls so that the light emission timing of the white light source 2 and the image capturing time of the image sensor 5 are synchronized, and a switching device 6 that selects only a fluorescent image from the images captured by the image sensor 5 by the controller 10. The image from the image enhancing device 7 that enhances the fluorescence image selected by the switching device 6 and the images from the image enhancing device 7 and the image pickup device 5 are combined into one.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention accumulates a photosensitizer having an affinity for a lesion such as a tumor in advance, and irradiates the photosensitizer with light having a wavelength matching the absorption wavelength of the photosensitizer to excite the photosensitizer. The present invention relates to an optical diagnostic device used for diagnosing a lesion.

[0002]

2. Description of the Related Art As a conventional example of this type of diagnostic apparatus, Japanese Patent Publication No. 63-9464 is disclosed.

FIG. 7 is a schematic block diagram showing an apparatus relating to the above publication. When diagnosing cancer with this device, a hematoporphyrin derivative which is a photosensitizer is absorbed into cancer and surrounding tissues. This hematoporphyrin derivative is excited at a wavelength of 405 nm and emits 630 nm and 690 n
Generate fluorescence with two peaks of m. When performing a diagnosis, the laser light source 71 irradiates the lesion with the light having the excitation wavelength of 405 nm by the endoscope 72. The lesion area where the hematoporphyrin derivative is accumulated emits fluorescence by 405 nm excitation light. The light obtained by irradiating the lesion with 405 nm excitation light is (1) scattered or reflected light of the 405 nm light itself from the lesion (2) autofluorescence generated by normal tissue at a wavelength near 580 nm (3) hematoporphyrin There are three types of fluorescence from derivatives. In order to separate these lights, the spectrum analysis of the obtained light is performed using the spectroscope 73 and the spectrum analyzer 74, and the result is displayed on the display device 75.

On the other hand, a white light source 7 is used to observe the lesion.
6 is introduced into the lesion by the endoscope 72 in the same manner as described above. The white light source 76 emits light in pulses so as not to interfere with the spectrum analysis. The control unit can synchronize the pulse emission of the excitation light laser light source 71 and the spectrum imaging of the spectrum imaging device, and efficiently capture the fluorescence excited by the pulse emission. The control device adjusts the light emission timing according to the timing of the pulse light emission so that the lesion area can be observed simultaneously with the spectrum analysis. Reference numeral 77 is an image pickup element for picking up an image of a lesion such as the presence or absence of cancer tissue, which is displayed on the display device 78.

[0005]

In the above conventional structure, there is a problem that the laser light source emits light in pulses in addition to the white light source, and it is necessary to strictly control the timing.

It is an object of the present invention to provide an optical diagnostic apparatus which uses pulsed light emission as a white light source and simplifies the structure of the apparatus and at the same time can utilize the image pickup element for both lesion observation and fluorescence observation.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the conventional structure, the present invention provides an excitation light source for continuously generating a light beam having an excitation wavelength and intermittent white light for observing a lesion. Generating a white light source, an optical separation means for separating the excitation light reflected from the lesion, fluorescence, and white light into excitation light and light of other wavelengths, and the excitation light was removed by the optical separation means. An imaging device that captures an optical image from a lesion, a control device that controls the light emission timing of the white light source and the imaging time of the imaging device to be synchronized, and an image captured by the imaging device by the control device. A switching device that selects only the fluorescence image, an image enhancement device that enhances the fluorescence image selected by the switching device, and an image that combines the images from the image enhancement device and the image sensor into one image. It is set to be equipped with a synthesizer.

The above-mentioned white light source is adapted to intermittently generate white light for observing a lesion, but this white light source has a periodic light intensity for observing the lesion. The changing white light may be generated.

By these means, the present invention realizes a diagnostic apparatus which can utilize the image pickup device for both lesion observation and fluorescence observation.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the invention according to claim 1 comprises irradiating a lesion having previously accumulated a photosensitizer having an affinity for a tumor or the like with a light beam having an excitation wavelength to form a photosensitizer. In an optical diagnostic device for observing and diagnosing fluorescence, an excitation light source that continuously emits light of the excitation wavelength, a white light source that intermittently emits white light to observe a lesion, and a reflection from the lesion Of the excitation light, the fluorescence, and the white light that have been excited, and an optical separation means for separating the excitation light and light of other wavelengths, and an image pickup device for photographing an optical image from a lesion part where the excitation light is removed by the optical separation means. A control device for controlling the light emission timing of the white light source and the image pickup time of the image pickup device to be synchronized; and a switching device for selecting only a fluorescence image from images taken by the image pickup device by the control device. An image enhancing device for enhancing the fluorescent image selected by the switching device, and an image synthesizing device for synthesizing the images from the image enhancing device and the image pickup device into one, ,
According to a second aspect of the invention, the white light source of the invention according to the first aspect is changed to a white light source that emits white light whose light intensity periodically changes to observe a lesion.

Further, both of the first and second aspects of the present invention have an effect that the structure of the apparatus is simple and at the same time the image pickup element can be used for both the lesion observation and the fluorescence observation.

In the invention according to claim 3, the excitation light source is a laser light source, and in the invention according to claim 4, the laser light source is a semiconductor laser device, and the invention according to claim 5 is Then, the photosensitizer having an affinity for the tumor is a chlorin photosensitizer, and the wavelength of the excitation light generated by the excitation light source is 664 nm. Further, in the invention according to claim 6, the excitation light is The separating means separates the excitation light by transmitting the wavelength of the excitation light and reflecting the other wavelengths.

The inventions according to claims 3 to 6 all disclose inventions relating to means for carrying out the present invention concretely and effectively.

[0014]

【Example】

(Embodiment 1) The present invention will be described in detail below with reference to FIGS. 1, 2, 3 and 4.

FIG. 1 shows a first embodiment of the present invention. 1
Is a laser light source for excitation, 2 is a white light source for observing a lesion, 3 is light for introducing light from the laser light source 1 and white light source 2 into the lesion, and for deriving light from the lesion. An endoscope 4 is a bandpass filter that transmits the wavelength of laser light and reflects other wavelengths, and 5 is an image sensor using a CCD for observing the state of the lesion after separating the excitation light. Is a switching device for selecting whether or not the image picked up by the image pickup device 5 is next emphasized by a control device, and 7 is an image emphasis device for performing image emphasis on the image picked up by the image pickup device 5. 8 is an image synthesizing device for synthesizing the image emphasized by the image emphasizing device 7 and the image taken by the image pickup device 5, 9 is a display device for displaying the measurement result,
Reference numeral 10 is a control device for performing overall control.

FIG. 2 shows the operation timing of the first embodiment. In FIG. 2, the white light source 2 repeats irradiation and non-irradiation at regular intervals, and the laser light source 1 always irradiates. Further, the switching device 6 directly outputs the image captured by the image sensor 5 to the image synthesizing device 8 when the white light source 2 emits white light, and captures the image when the white light source 2 does not emit white light. This indicates that the image captured by the element 5 is output to the image enhancing device 7.

FIG. 3 schematically shows the wavelength distributions of the amounts of white light, laser light, and fluorescence, the reflection characteristics of the bandpass filter, and the wavelength distributions of white light and fluorescence reflected by the bandpass filter.

FIG. 4 shows a configuration example of the image synthesizing device 8. In the present embodiment, the image synthesizing device 8 stores the images from the switching device 6 and the image emphasizing device 7, and the image storing devices 11 and 12 capable of reading the stored images at the timing of image output, and the image storing devices. The image superimposing circuit 13 for adding the image information output from the devices 11 and 12 into one, and timing of image output,
1 and 12, an image output timing device 14 which gives timing for reading image information.

The operation of this embodiment will be described below. First,
A case where white light is not emitted from the white light source 2 will be described. Since the white light is not irradiated, only the laser light from the laser light source 1 is irradiated to the cancer tissue inside the body through the endoscope 3. The photosensitizer remaining in the cancer tissue is excited by the laser light and emits fluorescence having a wavelength longer than that of the laser light. For example, in the case of a chlorin-based photosensitizer remaining in the body, when it is irradiated with laser light of 664 nm, fluorescence having a wide wavelength distribution with a peak around 670 nm is generated. Laser light reflected on the surface of the cancer tissue,
The fluorescence from the photosensitizer is guided to the outside of the body through the endoscope 3. The laser light passes through the bandpass filter 4 as it is, and most of the fluorescence having a longer wavelength than the laser light is reflected by the bandpass filter 4, and the laser light and the fluorescence are separated. The image sensor 5 captures the lesion area as an image of fluorescence. The switching device 6 outputs the image from the image pickup device 5 to the image enhancing device 7 when the white light is not emitted as shown in FIG. The image enhancing device 7 amplifies a faint image made of fluorescence to enhance the image in which the range emitting the fluorescence can be confirmed, and outputs the image to the image synthesizing device 8. The image composition device 8 temporarily stores the image from the image enhancement device 7 in the image storage device 12.

Next, the operation when the white light source 2 emits white light will be described. The light emitted from the laser light source 1 and the white light 2 is applied to the cancer tissue in the body through the endoscope 3. The photosensitizer remaining in the cancer tissue emits fluorescence due to the laser light of the excitation wavelength, but since the light from the white light source is also included in the same wavelength band, the difference in the image of the affected area depending on the presence or absence of fluorescence is only fluorescence. Not significantly observed compared to. White light and laser light reflected on the surface of the cancer tissue,
The fluorescence from the photosensitizer is guided to the outside of the body through the endoscope 3. The laser light passes through the bandpass filter 4 as it is, and most of the fluorescent light and white light having a longer wavelength than the laser light is reflected by the bandpass filter 4, and the laser light is separated from the white light and the fluorescent light. The image sensor 5 captures the lesion as an image composed of fluorescence and reflected light of white light.
Since the image of this lesion is a sufficiently bright image as compared with the case of only fluorescence, it is not necessary to enhance the image. Therefore,
The switching device 6 directly outputs the image from the image sensor 5 to the image synthesizing device 8 when the white light is emitted as shown in FIG. The image synthesizing device 8 stores the image from the switching device 6 in the image storage device 11.

As described above, when the irradiation and non-irradiation of the white light are repeated, the two image storage devices 1 of the image synthesizing device 8 are
A white light image and an enhanced fluorescence image are stored in each of 1 and 12. In the image synthesizing device 8, each image information is sequentially read from the image storage devices 11 and 12 in accordance with the timing signal from the image output timing device 14 which gives the image output timing. The two pieces of read image information are added together by the image superimposing circuit 13 to form one image. As a result, the image thus synthesized is an image in which the image of the lesion part due to white light and the highlighted fluorescence image are overlapped, and it is possible to clearly observe from which position of the lesion part the fluorescence is emitted by the display device 9.

In addition to simply adding the images in the image superposing circuit 13, for example, the image storage device 1
When the image information of the fluorescence image read out from No. 2 has a certain brightness or more, the image information from the image storage device 12 is used, and when the brightness is less than that, the image storage device 11 is used.
It is also conceivable that if a fluorescent image having a certain brightness or more is replaced with an image of white light and the image is observed by performing an operation of selecting the image information from (3).

(Embodiment 2) FIG. 5 is a diagram showing the operation timing of Embodiment 2 of the present invention. The configuration of the second embodiment is the same as that of FIG. This Example 2 is the same as Example 1 as shown in FIG.
Unlike the white light source 2, the white light source 2 periodically repeats bright and dark, but the irradiation is not interrupted. The laser light source 1 is always irradiating. The switching device 6 directly outputs the image photographed by the image sensor 5 to the image synthesizing device 8 at the timing when the white light source 2 strongly emits the white light, and at the timing when the white light from the white light source 2 becomes dark. , Outputting an image captured by the image sensor 5 to the image enhancement device 7.

FIG. 6 is a diagram for explaining the difference in contrast between the presence and absence of fluorescence due to the difference in white light intensity.

FIG. 6A shows the combined intensity of fluorescence and white light when the intensity of white light is sufficiently high. Here, it is expected that the ratio between the case where the contribution of the fluorescence to the light intensity is not considered and the case where it is considered is close to 1, and it is difficult to recognize the difference due to the presence or absence of the fluorescence when the white light is strong.

On the other hand, FIG. 6B shows the combined intensity when the white light intensity is weak. Although the light intensity is smaller than that of (a), the rate of change in light intensity due to the presence or absence of fluorescence is large, and the difference is easily recognized.

Hereinafter, FIG. 1, FIG. 3, FIG. 4, FIG. 5 and FIG.
The operation of the second embodiment will be described with reference to.

In this embodiment, the endoscope 3 is used for the cancerous tissue in the body.
Through the laser light from the laser light source 1 and the white light source 2
And the white light from. The photosensitizer remaining in the cancer tissue emits fluorescence by the laser light having the excitation wavelength.

As shown in FIG. 6 (a), at the time when the white light from the white light source 2 is sufficiently strong, the difference between the images of the affected area due to the presence or absence of fluorescence is not significantly observed because the white light of the same wavelength band exists. . White light and laser light reflected on the surface of the cancer tissue and fluorescence from the photosensitizer are guided to the outside of the body through the endoscope 3. The laser light passes through the bandpass filter 4 as it is, and most of fluorescent light and white light having a longer wavelength than the laser light is reflected by the bandpass filter 4,
Laser light, white light, and fluorescence are separated. The image sensor 5 captures the lesion as an image composed of fluorescence and reflected light of white light. As shown in FIG. 5, the switching device 6 outputs the image from the image sensor 5 directly to the image synthesizing device 8 when the white light is strongly irradiated. The image synthesizing device 8 stores the image from the switching device 6 in the image storage device 11.

Next, at the time when the white light is dimmed, even if fluorescence from the cancer tissue and white light of the same wavelength are present, FIG.
As shown in, the presence or absence of fluorescence can be easily observed. At this time,
The image captured by the image sensor 5 is output to the image enhancing device 7 by the switching device 6. The image intensifying device 7 amplifies an image in which a difference due to the presence or absence of fluorescence is recognized, emphasizes the image in which the range emitting the fluorescence can be confirmed, and outputs the image to the image synthesizing device 8. The image composition device 8 temporarily stores the image from the image enhancement device 7 in the image storage device 12.

The subsequent operation is the same as the operation after being stored in the image storage device 11 in the first embodiment.

[0032]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, an excitation light source that continuously emits a light beam having an excitation wavelength, a white light source that intermittently emits white light for observing a lesion, and a reflection from the lesion. Of the excitation light, the fluorescence, and the white light that have been excited, and an optical separation means for separating the excitation light and light of other wavelengths, and an image pickup device for photographing an optical image from a lesion part where the excitation light is removed by the optical separation means. A control device that controls the light emission timing of the white light source and the image capturing time of the image sensor to synchronize with each other; and a switching device that selects only a fluorescence image from images captured by the image sensor by the controller.
An image enhancing device that enhances the fluorescent image selected by the switching device, and an image synthesizing device that synthesizes the images from the image enhancing device and the image pickup device into one, and pulse light emission is performed only by a white light source. Thus, an optical diagnostic device can be realized which simplifies the configuration of the device and at the same time can utilize the image pickup element for both lesion observation and fluorescence observation.

Further, an excitation light source that continuously emits a light beam having an excitation wavelength, a white light source that emits white light whose light intensity changes periodically for observing the lesion, and an excitation reflected from the lesion. Optical separation means for separating excitation light and light of other wavelengths among light, fluorescence, and white light; an image sensor for capturing an optical image from a lesion part where excitation light is removed by the optical separation means; A control device that controls so that the light emission timing of the white light source and the imaging time of the imaging device are synchronized, a switching device that selects only a fluorescence image from the images captured by the imaging device by the control device, and the switching device. And an image synthesizing device for synthesizing the images from the image enhancing device and the image sensor into one image enhancing device for enhancing the fluorescence image selected by
The present invention realizes an optical diagnostic apparatus that can be realized by simply changing the light intensity of a white light source, that is, changing the light intensity.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical diagnostic apparatus according to an embodiment of the present invention.

FIG. 2 is an operation timing chart in the first embodiment of the present invention.

FIG. 3 is a wavelength characteristic diagram in an example of the present invention.

FIG. 4 is a block diagram showing a configuration of the image synthesizing apparatus.

FIG. 5 is an operation timing chart in the second embodiment of the present invention.

FIG. 6 is a relationship diagram between fluorescence and white light.

FIG. 7 is a block diagram showing a configuration of a conventional optical diagnostic apparatus.

[Explanation of symbols]

 1 Laser Light Source 2 White Light Source 3 Endoscope 4 Band Pass Filter 5 Image Sensor 6 Switching Device 7 Image Enhancement Device 8 Image Synthesizer 9 Display Device 10 Control Device 11, 12 Image Storage Device 13 Image Superimposing Circuit 14 Image Output Timing Device

Claims (6)

[Claims] 1. A photodiagnostic device for irradiating a lesion, which has previously accumulated a photosensitizer having an affinity for a tumor or the like, with a light beam having an excitation wavelength, and observing fluorescence from the photosensitizer to make a diagnosis. Excitation light source that continuously emits light, a white light source that intermittently emits white light for observing the lesion, and excitation light, fluorescence, and white light that is reflected from the lesion and the excitation light Optical separation means for separating light of wavelengths other than, an image pickup element for taking an optical image from a lesion part where excitation light is removed by the optical separation means, light emission timing of the white light source, and image pickup time of the image pickup element A control device for controlling so as to synchronize with each other, a switching device for selecting only a fluorescence image among images captured by the image sensor by the control device, and an enhancement of the fluorescence image selected by the switching device. An optical diagnostic apparatus comprising: an image enhancing device for performing the image enhancement; and an image synthesizing device for synthesizing images from the image enhancing device and the image sensor into one image. 2. An optical diagnostic apparatus for diagnosing by irradiating a lesion having a photosensitizer having an affinity for a tumor or the like with a light beam having an excitation wavelength to observe fluorescence from the photosensitizer and diagnosing the fluorescence. Of the excitation light, fluorescence, and white light that are reflected from the lesion, and the excitation light source that continuously emits the light beam of, the white light source that emits the white light whose light intensity changes periodically to observe the lesion. Of these, optical separation means for separating the excitation light and light of other wavelengths, an imaging element for capturing an optical image from the lesion part where the excitation light is removed by the optical separation means, the light emission timing of the white light source, and the A control device for controlling so that the image pickup time of the image pickup element is synchronized;
From the image enhancement device and the image pickup device, a switching device that selects only a fluorescence image among images captured by the image pickup device by the control device, an image enhancement device that enhances the fluorescence image selected by the switching device, And an image synthesizing device for synthesizing the images of 1. into an optical diagnostic device. 3. The optical diagnostic apparatus according to claim 1, wherein the excitation light source is a laser light source. 4. The optical diagnostic apparatus according to claim 3, wherein the laser light source is a semiconductor laser device. 5. The photodiagnosis according to claim 1, wherein the photosensitizer having an affinity for tumor is a chlorin photosensitizer, and the wavelength of the excitation light generated by the excitation light source is 664 nm. apparatus. 6. The light according to claim 1, wherein the excitation light separating means separates the excitation light by transmitting the wavelength of the excitation light and reflecting the other wavelengths. Diagnostic device.