JP3823096B2 - Imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an imaging device that images abnormal tissue in the body that cannot be recognized by endoscopy using white light, and localizes and identifies the region, and in particular, images abnormal bronchial tissue to detect inflammation and nakedness. The present invention relates to an imaging apparatus suitable for detecting conditions such as dysplasia and non-invasive early cancer (original cancer).
[0002]
[Prior art]
Currently, the most effective method of examining a patient's body cavity is by an endoscope. Usually, a flexible endoscope such as a bronchoscope is often used to examine the passage of lung air. A bronchoscope, similar to an endoscope, illuminates the surface to be examined with visible white light. This irradiation light is guided into the air passage (trachea) of the lung by a fiber optic illumination light guide. The light reflected and diffused from the bronchial tissue is received by a projection lens that forms an image in the imaging fiber bundle of the bronchoscope. An imaging fiber bundle is composed of thousands of coated fibers each of which transmits a coherent image outside the body. This image is then projected through the bronchoscope eyepiece for human examination. Since the color video camera can be attached to the eyepiece of the bronchoscope, a color image of reflected and scattered white light (broadband light) can be projected on the color video monitor.
[0003]
[Problems to be solved by the invention]
When using a common bronchoscope, large invasive cancers can be found immediately. However, small inflammations, nakedness, dysplasia, early lung cancer, etc. cannot be found immediately with such devices.
[0004]
Several methods have been developed that can visualize small early stage lung cancer that is difficult to detect with a normal white light bronchoscope. All of these are combined with a tumor stereotactic agent, for example, a haematoporphyrin derivative or Porfimer sodium that is particularly visible and attached to the tumor tissue. Some of these agents fluoresce, and these fluorescence can be detected by non-imaging and imaging devices (Profio AE et al., Med Phys 6: 532-535, 1979; Propfio AE). Et al., Med Phys 11: 516-520,1984; Prpfio AE et al., MedPhys 13: 717-721,1986; Hayata Y et al., Chest 82: 10-14,1982; Kato (Kato) A, Cortese DA, Clin Chest Med 6: 237-253, 1985; Montan S et al., Opt Letters 10: 56-58, 1985). The problem with these techniques is that the drug has serious side effects and therefore the use of the drug is not suitable for diagnostic purposes. In addition, non-imaging devices such as ratiofluorometer exploration (Profio AE et al., Med. Phys 11: 516-520, 1984) can be used to accurately detect abnormal areas. Localization and identification cannot be obtained.
[0005]
Another method of detecting invasive tumors is described in US Pat. No. 4,930,516 granted to Alfano et al. On June 5, 1990. Alfano et al. Are based on the fact that the fluorescence spectrum of cancer tissue is different from that of normal tissue, and the maximum fluorescence peak of tumor tissue is shifted to a short blue wavelength (from 531 nm to 521 nm). A method for detecting cancer is disclosed. These observations are based on incised large (invasive) animal and human tumors in the container, and not on the human body. In addition, there are no records of other abnormal cells such as inflamed tissue or tissue prior to cancer. We measured the fluorescence of patient tissue with different excitation wavelengths including 405 nm, 442 nm, and 488 nm with a specially shaped optical multichannel analyzer that can be attached to a conventional bronchoscope. In response to the observations by Alfano et al., We did not find differences in the shape of the fluorescence spectrum between normal and tumor tissues using these excitation wavelengths. In particular, there was no shift of the emission peak to the blue side. We have observed sufficient differences in all fluorescence intensities, especially in the green region of the visible spectrum. A small but sufficient decrease in all fluorescence intensities was also observed before cancer and in non-cancerous lesions (dysplasia and metaplasia).
[0006]
The decrease in green fluorescence is due to a decreased level of the oxidized form of riboflavin. Riboflavin is strongly fluorescent in the green region and is considered to react well to strong green fluorescence in normal human lung tissue. In cancer tissue, riboflavin has been found to be less (Pollack Ma et al., Cancer Res 2: 739-743,1942), and is now decreasing. This causes a decrease in autofluorescence of the lung tissue before becoming malignant and malignant lung tissue.
[0007]
The study led to an example of such tissue reduced autofluorescence of dysplastic lung tissue and cancer. The main difference between abnormal and normal tissue was revealed by a large decrease in fluorescence intensity in the part of the spectrum from 480 nm to 600 nm. At wavelengths greater than about 635 nm, tissue autofluorescence is almost identical for abnormal and normal tissues. In the test, an excitation light of 442 nm, 405 nm, and 488 nm was used, and an abnormal tissue was compared with a normal tissue to obtain a result. All these data were obtained from the body with a conventional fiber bronchoscope using an optical multichannel analyzer.
[0008]
The method using a ratio of two or more wavelengths was first described by Profio and his collaborators, as the autofluorescence emitted without a change in the spectrum of the abnormal tissue was observed to be greatly reduced. By patients taking fluorescent drugs such as Photofrin (Profio et al., Med. Phys. 11: 516-520, 1984), which cannot normally distinguish between normal and abnormal cells using only autofluorescence Experimented.
[0009]
The present invention has been made in view of the above points. An object of the present invention is to provide an imaging apparatus capable of detecting and identifying a region of abnormal tissue (particularly lung) in the body using the intensity of autofluorescence of the tissue. It is to provide.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, an imaging apparatus according to the present invention includes a light source that emits excitation light including a plurality of wavelengths capable of generating intrinsic autofluorescence related to abnormal tissue and normal tissue, and light including the excitation light and tissue. The irradiation means for exciting the tissue so as to emit the intrinsic autofluorescence, the collecting means for collecting the autofluorescence emitted from the tissue, and the autofluorescence, the autofluorescence intensity of the abnormal tissue is normal. A filtering means for filtering within a spectral band substantially different from the autofluorescence intensity of the tissue and a spectral band in which the autofluorescence intensity of the abnormal tissue is substantially equal to the autofluorescence intensity of the normal tissue; An optical means for blocking the autofluorescence and forming at least two filtered autofluorescence images of the tissue, and a display for displaying the obtained image so as to distinguish between normal and abnormal tissues It includes a stage, a.
[0011]
The imaging apparatus having the above configuration detects and identifies an abnormal tissue of a patient using the autofluorescence characteristics of the tissue. The formation and analysis of the autofluorescence image is performed using a high sensitivity detector such as an optical amplification CCD camera. A virtual image is formed by sending one image to the red channel of the RGB color monitor and one image to the green channel. By forming two images simultaneously or at intervals of several milliseconds, a virtual image can be formed immediately. And this virtual image can clearly distinguish the tissue committed by the disease from the surrounding normal tissue.
The present invention further provides the following items 1 to 22.
Item 1. A light source that emits excitation light including a plurality of wavelengths that can generate inherent autofluorescence related to abnormal tissue and normal tissue, and the tissue that emits the inherent autofluorescence by irradiating the tissue with the excitation light and light. Irradiating means for exciting the tissue, collecting means for collecting the autofluorescence emitted from the tissue, the autofluorescence, a spectral band in which the autofluorescence intensity of the abnormal tissue is substantially different from the autofluorescence intensity of the normal tissue, and A filtering means for filtering in a spectral band in which the autofluorescence intensity of the abnormal tissue is substantially equal to the autofluorescence intensity of the normal tissue; and at least two filters of the tissue that block the filtered autofluorescence An imaging apparatus for imaging an affected area in a tissue, comprising: optical means for forming a self-fluorescent image; and display means for displaying the obtained image so as to distinguish between a normal tissue and an abnormal tissue.
Item 2. The display means includes a color monitor, and the optical means is supplied to the color monitor as two different color signals that form a display image capable of analyzing and discriminating abnormal tissue and normal tissue by color change. Form one image,
Item 2. The imaging device according to Item 1.
Item 3. Item 2. The imaging device according to Item 1, wherein the light source includes a laser light source that emits desired excitation light.
Item 4. Item 4. The imaging device according to Item 3, wherein the light source includes a white light source for forming a white light image collected, formed and displayed together with the autofluorescence image.
Item 5. Item 5. The imaging apparatus according to Item 4, further comprising tuning means for switching between tissue irradiation by the laser light source and tissue irradiation by the white light source.
Item 6. The tuning means includes shielding means for shielding light from the other light source in combination with the laser light source and the white light source, respectively, when the tissue is irradiated by one of the laser light source and the white light source. 5. The imaging device according to 5.
Item 7. Item 7. The imaging apparatus according to Item 6, wherein the shielding means includes a shutter.
Item 8. Item 2. The imaging apparatus according to Item 1, wherein the irradiation means includes an optical light guide for a bronchoscope.
Item 9. Item 2. The imaging apparatus according to Item 1, wherein the collecting means includes an imaging fiber bundle of a bronchoscope and a focusing lens that cooperates with the imaging fiber bundle.
Item 10. The optical means includes an imaging light detector that forms the filtered self-fluorescent image, and the filtering means is provided so as to be able to enter the optical path of the emitted self-fluorescence and is filtered. Item 2. The imaging device according to Item 1, comprising a plurality of filters for forming an autofluorescence image.
Item 11. Item 11. The imaging device according to Item 10, wherein the photodetector includes an optical amplification CCD.
Item 12. Other optical means for capturing a white light image when the white light image is generated, the other optical means being provided so as to be insertable into the collected light, and supplying the white light image to a color video camera. Item 11. The imaging device according to Item 10, further comprising a movable mirror that deflects toward the image.
Item 13. Item 2. The imaging apparatus according to Item 1, wherein the optical means includes at least two imaging light detectors that simultaneously form a plurality of filtered autofluorescent images, and each of the imaging light detectors includes filtering means.
Item 14. Item 14. The imaging apparatus according to Item 13, further comprising spectroscopic means for directing the emitted autofluorescence image to each of the at least two imaging photodetectors.
Item 15. Item 15. The imaging apparatus according to Item 14, wherein the spectroscopic means includes a dichroic miter.
Item 16. Item 14. The imaging device according to Item 13, wherein the imaging light detector includes an optical amplification CCD.
Item 17. Other optical means for capturing a white light image when the white light image is generated, the other optical means being provided so as to be insertable into the collected light, and supplying the white light image to a color video camera. Item 14. The imaging device according to Item 13, further comprising a mirror capable of deflecting toward the target.
Item 18. Item 2. The imaging apparatus according to Item 1, wherein the optical unit includes a prism that simultaneously separates the collected light in a plurality of directions, and a filtering unit and a light detecting unit that receive the separated light.
Item 19. Image processing means, wherein the image processing means digitizes the filtered autofluorescent image, and enhances the digitized image by a conversion operation method, and immediately creates a calculated virtual image. Item 2. The imaging apparatus according to Item 1, further comprising image enhancement means.
Item 20. Item 20. The imaging apparatus according to Item 19, further comprising storage means for storing the digitized image.
Item 21. Item 20. The imaging apparatus according to Item 19, wherein the image processing means includes an image processing board in the computer.
Item 22. Item 20. The imaging apparatus according to Item 19, wherein the storage means includes a computer memory.
[0012]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0013]
Figures 1 to 4 show examples of decreased tissue autofluorescence for dysplastic bronchial tissue and carcinoma in situ, respectively. The main difference between normal and abnormal tissue is manifested by a significant decrease in fluorescence intensity appearing in the 480-600 nm spectral region. At a wavelength of about 635 nm or more, the tissue autofluorescence of normal tissue and abnormal tissue is almost equal. FIG. 1 and FIG. 2 respectively show the measurement results when the tissue is excited using 442 nm helium-cadmium laser light. FIG. 1 shows tissue autofluorescence spectra of normal tissue and dysplastic tissue, and FIG. 2 shows tissue autofluorescence spectra of carcinoma in situ against normal tissue for different patients. Similar results were obtained when other excitation light, for example, 405 nm excitation light shown in FIG. 3 or 488 nm excitation light shown in FIG. 4 was used. In both the cases of FIG. 3 and FIG. 4, the in situ carcinoma tissue of multiple patients was compared to the normal lung tissue of these patients. All these data were obtained in the body during routine bronchoscopy using an optical multichannel analyzer.
[0014]
The apparatus of the present invention is configured to identify and describe an abnormal tissue using a difference in fluorescence intensity in different regions of the spectrum.
[0015]
FIG. 5 schematically shows an embodiment in which the imaging apparatus according to the present invention is used for examination of bronchial tissue of a patient's lung. As can be seen from this figure, the imaging device is integrated with a conventional bronchoscope used for examination of bronchial tissue of the lung.
[0016]
The imaging apparatus includes a light source 1 that emits excitation light, and the light source emits excitation light including a plurality of wavelengths that can generate unique autofluorescence spectra related to normal tissue and abnormal tissue. The light source 1 is shown in an enlarged manner in FIG. 6 and preferably includes a laser light source 7 capable of emitting excitation light having a selected desired wavelength. In addition, the apparatus includes a white light source such as the incandescent xenon light source 8, and can emit white light if necessary. The laser light source 7 is used to form a virtual image obtained from tissue autofluorescence, and the white light source 8 is used to form a color image of reflected / diffused white light.
[0017]
Light from each light source enters the tuning means, which can selectively irradiate the tissue with the light from the laser light source 7 and the white light source 8. In the embodiment shown in FIG. 6, the tuning means comprises shielding means having electronically controlled shutters 9 and 13, which cooperate with the laser light source 7 and the white light source 8, respectively. When the shutter 9 is opened and the laser beam can pass, the shutter 13 is closed to restrict the passage of white light. When the shutter 9 is closed, the shutter 13 is opened to allow white light to pass. The laser light from the laser light source 7 passes through an open shutter 9, a mirror 10 having a pinhole, and a lens 11, and this lens focuses the laser light on the irradiation means. The irradiation means includes a light guide 12 of a conventional bronchoscope and irradiates light onto the tissue. The light guide 12 guides the excitation light to the tissue region to be examined. When irradiated with laser light, the tissue emits intrinsic autofluorescence indicative of normal and abnormal tissue. When a standard white light irradiation image is formed, the shutter 9 is closed, and the previously closed shutter 13 is opened. Thereby, the light from the white light source 8 passes through the shutter 13. Subsequently, the white light is filtered by the neutral filter group 14, then reflected by the mirror 15 and incident on the lens 16, and after being focused by this lens, is reflected by the mirror 10, passes through the lens 11 and passes through the bronchoscope. Focused on the light guide 12. The neutral filter group 14 is used to make white light from the white light source 8 have an intensity suitable for an optical sensor used in the imaging apparatus. Thereby, the white light guided to the tissue irradiates the tissue to be examined. The light guide 12 also distributes light uniformly over the entire area to be inspected.
[0018]
In this embodiment, the bronchoscope functions as a collecting means for collecting a plurality of images into a shape of a bronchoscope lens (not shown), and this bronchoscope lens collects diffused light and reflected light or autofluorescence emitted from the lungs. And transmitted outside the body by the imaging fiber bundle 2 of the bronchoscope. Such collected light is guided to an eyepiece lens 21 (see FIG. 7) of a bronchoscope connected to the imaging fiber bundle 2.
[0019]
The collected light is incident on the image forming module 3 from the eyepiece 21 of the bronchoscope. The image forming module 3 includes filtering means for filtering autofluorescence and optical means for blocking the filtered light. It has. Various image forming modules 3 can be implemented.
[0020]
FIG. 7 shows an image forming module having filtering means and optical means, which forms an emitted autofluorescent image. In the embodiment, the filtering means for filtering the autofluorescence has a plurality of continuous filters that can continuously enter the optical path of the emitted autofluorescence, and forms a continuous filtered autofluorescence image. Specifically, the image forming module includes a filter wheel 18, which is movably provided below the optical means of the image forming module. When the laser light source 7 is used, it is necessary to filter the autofluorescence generated in at least two spectral bands. In one spectral band, the autofluorescence intensity for the abnormal tissue is substantially different from the autofluorescence intensity for the normal tissue, and in the other spectral band, the autofluorescence intensity for the abnormal tissue is substantially the same as the autofluorescence intensity for the normal tissue. Match. For example, the filter wheel 18 is provided with two filters according to the eigenspectral band for lung examination as shown in FIGS. In this case, a green filter of 500 ± 20 nm and a red long-pass filter of 630 nm are used for 442 nm or 405 nm laser light. The green filter filters the autofluorescence into a certain spectral band where the autofluorescence intensity of the abnormal tissue is substantially different from the autofluorescence intensity of the normal tissue. The red long pass filter filters the autofluorescence in a certain spectral band where the autofluorescence intensities of the abnormal tissue and the normal tissue substantially match. These two filters are mounted on the filter bore 18 so that half of them overlap each other. By rotating the filter wheel 18 at a desired speed, the autofluorescent image filtered by the green filter and the red long pass filter is an optical means having a single high sensitivity detector 17, such as an image-multiplied CCD camera. Are sequentially imaged.
[0021]
The image forming module described above includes other optical means for capturing a white light image reflected and diffused when the tissue is irradiated using the white light source 8. That is, as shown in FIG. 7, the image forming module includes a movable mirror 20, and this mirror 20 is provided so as to be inserted into the optical path of the collected light transmitted by the eyepiece lens 21. The mirror 20 can be aligned to a position where the white light is deflected to the color video camera 22 for capturing an incandescent image. Therefore, the movement of the mirror 20 is controlled so as to deflect the collected light to the video camera 22 only when the white light source 8 is used for tissue irradiation. Further, when the white light source 8 is used, a color image can be formed on the color monitor by the same method as a conventional bronchoscope. When the laser light source 7 is used to irradiate the tissue, the mirror 20 is retracted from the optical path, allowing autofluorescence filtering and subsequent imaging by the detector 17.
[0022]
FIG. 8 shows another embodiment of the image forming module. According to this embodiment, the optical means comprises at least two photodetectors that simultaneously capture a plurality of filtered autofluorescence images. Each photodetector has cooperating filtering means. In order to collect a plurality of autofluorescence images simultaneously, the filter wheel 18 in the embodiment shown in FIG. 7 is replaced by a spectroscopic means such as a dichroic mirror 24. The dichroic mirror 24 allows passage of red light having a wavelength longer than 600 nm and reflects light having a shorter wavelength. In this case, filters 25 and 26 may further be provided to more accurately select the desired autofluorescence, each image being two independent high-sensitivity lights such as CCD cameras 17 and 23 that have been image-multiplied. An image is formed on the detector. In FIG. 8, a filter 25 is a 630 nm red long-pass filter that further filters the red light from the dichroic mirror 24 into a certain spectral band where the autofluorescence intensities of normal and abnormal tissues substantially coincide. The filter 26 is a 500 ± 20 nm green filter that filters autofluorescence into a spectral band where the autofluorescence intensity of abnormal tissue is substantially different from the autofluorescence intensity of normal tissue. The image picked up by the CCD camera 17 and / or 23 is sent to the red and green input channels of the RGB color monitor 5 (see FIG. 5).
[0023]
In the configuration shown in FIG. 7, the reflected / diffused white light image obtained by the white light source 8 is picked up by the color camera 22, and a common light source that can be inserted into the optical path while continuing to irradiate the tissue by the white light source 8. Using the movable mirror 20, it is directly displayed on the color monitor in order to visually recognize the inspected part.
[0024]
FIG. 9 shows another embodiment of the image forming module used together with the imaging apparatus according to the present invention. According to this embodiment, a prism 27 is provided, which simultaneously separates the collected light in a plurality of directions. By switching between the laser light source 7 and the white light source 8, an autofluorescence image and a white light image can be sequentially captured in a cycle of 33 milliseconds. This makes it possible to simultaneously observe a white light (broadband) color image and an autofluorescent virtual image on the display means.
[0025]
According to this embodiment, a special camera with three photodetectors 28, 29, 30 is used. The prism 27 then divides the collected light into three images, which are imaged by three independent photodetectors. The photodetectors 28 and 29 are provided with a CCD imaging device having optical amplifiers 37 and 38, and the photodetector 30 is provided with a normal CCD imaging device. Each photodetector has a filter 32, 33, 34, respectively, and an x, y, z micropositioning device. The filters 32 and 33 are the same as in the above-described embodiment, and constitute a 500 ± 20 nm green filter 32 and a 630 nm long-pass filter 33. The CCD image pickup device 30 includes a broadband blue filter 34.
[0026]
As can be seen from FIG. 5, the camera control unit 4 has three image signals, that is, a red signal formed by the red filter 32 and the amplified CCD image pickup device 28, a green filter 33, and an amplified CCD image pickup device 29. And the blue signal formed by the blue filter 34 and the non-amplified CCD image pickup device 30.
[0027]
In the above embodiments, a specially designed CCD imaging device may be used in place of the optical amplification detector. For example, particularly when high spatial resolution is not required, the pixels of a scientific CCD detector may be electronically incorporated into a very large single pixel capable of detecting very low signals.
[0028]
All or some of the image signals obtained by the various image forming modules according to the present invention described above may be displayed directly on the color monitor 5 or may be image processed by image processing means prior to display. Good. According to the present invention, it is also possible to switch between white light (broadband) irradiation and laser irradiation in about 1/30 seconds.
[0029]
When using a laser light source, the imaging module shown in FIG. 9 can simultaneously collect two autofluorescence images and blue diffuse / reflected excitation light images over two selected spectral bands. These images are synthesized visually or mathematically by the image processing means so that various tissues existing in the image can be discriminated. When using a white light source, the device collects red, green and blue reflected / diffused light images to form a standard color image of the tissue.
[0030]
Furthermore, the directionality, position, and depiction of various tissues may be emphasized by combining a color image with an autofluorescence image irradiated with a blue laser.
[0031]
Filters are used in various combinations depending on the tissue type and / or pathology so as to emphasize the difference between normal and affected tissue based on the intrinsic autofluorescence emitted from the affected tissue under examination.
[0032]
As shown in FIG. 5, the imaging apparatus according to the present invention preferably includes an image processing means such as an imaging board 35. The imaging board 35 is used in combination with a computer 6 that controls and adjusts the imaging apparatus. If necessary, the imaging board 35 can digitally process the image. That is, the imaging board 35 digitizes the filtered image obtained by the image forming module, enhances the digitized image by the conversion calculation method, and immediately calculates the calculated virtual image displayed on the video monitor 5. To produce. On the other hand, the digitized image may be stored in the memory of the computer 6.
[0033]
The pixel values of the digitized image are used to calculate the value of each pixel using a mathematical transformation. Thereby, all pixels representing the affected tissue are clearly distinguished from normal tissue pixels. The above process is also used to enhance the image, whereby the degree of pathology can be measured and other treatments and / or other examinations are possible.
[0034]
Various mathematical calculation methods have been provided so far, and these calculation methods can create various calculated virtual images from digitized autofluorescence images and diffused / reflected light images, as well as specific medical conditions. An autofluorescence image can be obtained over a unique spatial region suitable for the tissue. Preferred mathematical arithmetic methods that can be applied to programmed and digitized images include hue, contrast, intensity function, principal component decomposition arithmetic method, logarithm of difference, subtractive arithmetic method, etc. It is possible to depict normal tissue from the tissue that was ill.
[0035]
A report on a conversion method using a tumor stereotactic agent (Profio medical physics, 11: 516-520, 1984) has been found to be unsuitable for the imaging method by the present inventors. The above conversion methods often fail to find abnormal areas, except for large invasive cancers.
[0036]
According to the preferred embodiment of the present invention, image digitization and image processing are not required. That is, the difference between the normal part and the part committed by the disease can be visually recognized as a color difference by the color monitor 5 and human vision.
[0037]
When using the image forming module shown in FIG. 8 having two high sensitivity CCD cameras, one CCD camera transmits the red channel of the RGB color monitor 5 and the other CCD camera transmits the green channel. The red tissue autofluorescence for abnormal and normal bronchial tissue is approximately equal to each other. On the other hand, green tissue autofluorescence for abnormal sites is dramatically reduced relative to normal tissue autofluorescence. Therefore, the abnormal site is weaker in green and more red and / or light brown than in the surrounding normal tissue, and the surrounding normal tissue has a green autofluorescence stronger than the red autofluorescence of the normal tissue. Appears as bright green. According to the preferred embodiment of the present invention, the affected part can be immediately recognized without requiring image processing, and as a result, it is very economical.
[0038]
The same effect as described above can also be obtained when an image forming module having a single CCD camera and filter wheel 18 as shown in FIG. 7 is used. In this embodiment, the two obtained red and green autofluorescence images are electronically combined at a plurality of video ratios and sent to the RGB color monitor as red and green input signals.
[0039]
On the other hand, two spectral bands with different tissue autofluorescence are obtained and used as red and green signals for color display of a color monitor. This method can very clearly form a virtual image of inflamed tissue, dysplastic tissue and non-invasive cancer, and these tissues can be clearly distinguished from normal tissue. And a decrease in autofluorescence in the diseased tissue, especially in the green area, indicates the presence of the disease and the state of the disease.
[0040]
When a tumor stereotactic agent is used, the imaging device according to the present invention is used for visualizing small and large tumors. For example, for a stereotactic agent such as photofrin (porphyma sodium), the same filter can be used when the stereochemical emits autofluorescence with maximum values of 630 nm and 690 nm. Even in this case, all affected parts localized by the stereotactic agent can be clearly identified from normal tissues.
[0041]
In addition, this invention is not limited to the Example mentioned above, A various deformation | transformation is possible within the scope of this invention.
[0042]
【The invention's effect】
According to the present invention configured as described above, it is possible to provide an imaging apparatus capable of detecting and identifying an abnormal tissue region in the body using the intensity of autofluorescence of the tissue.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of an autofluorescence spectrum showing a difference between an irregularly shaped tissue and a normal tissue when an excitation wavelength is 442 nm.
FIG. 2 is a diagram showing an example of an autofluorescence spectrum showing a difference between an in-epithelial cancer tissue and a normal tissue when the excitation wavelength is 442 nm.
FIG. 3 is a diagram showing an example of an autofluorescence spectrum showing a difference between an intraepithelial cancer tissue and a normal tissue when the excitation wavelength is 405 nm.
FIG. 4 is a diagram showing an example of an autofluorescence spectrum showing a difference between an intraepithelial cancer tissue and a normal tissue in the case of an excitation wavelength of 488 nm.
FIG. 5 is a diagram schematically showing an imaging apparatus according to the present invention suitable for imaging abnormal bronchial tissue.
FIG. 6 is a diagram showing in detail an image forming module.
FIG. 7 shows filtered and optical mechanisms with a single sensitive detector used to form an autofluorescence image.
FIG. 8 is a diagram showing another filtering and optical mechanism for simultaneously obtaining a plurality of autofluorescence images using two high-sensitivity cameras.
FIG. 9 is a diagram showing still another filtering and optical mechanism including a prism capable of simultaneously capturing two autofluorescence images and one reflected / diffused white light image.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Light source, 3 ... Image formation module, 5 ... Color monitor, 7 ... Laser light source, 8 ... White light source, 9, 13 ... Shutter, 12 ... Light guide, 14, 25, 26, 32, 33, 34 ... Filter, 17 ... photodetector, 21 ... eyepiece.

Claims (2)

An apparatus for detecting abnormal tissue in a patient tissue sample, the apparatus comprising:
A light source for emitting either excitation light containing wavelengths that generate autofluorescence from abnormal tissue and normal tissue, or white light, which can quickly switch between the two light outputs A light source;
A light guide that delivers the excitation light or the white light to the tissue sample;
An imaging light guide that conveys light reflected from or originating from the tissue sample;
Light received from the imaging light guide is transmitted in a third spectral band including at least a first beam having a light in a first spectral band, a second beam having a second spectral band, and reflected excitation light. A prism that splits into a third beam having light, wherein the first spectral band has a wavelength range in which the autofluorescence intensity in normal tissue differs from the autofluorescence intensity in abnormal tissue; and The second spectral band has a wavelength range in which normal tissue autofluorescence intensity is substantially the same as abnormal tissue autofluorescence intensity; and
A first low light imaging detector and a second low light imaging detector, each forming a signal representative of a tissue sample with light in the first spectral band and light in the second spectral band; and A third imaging detector that forms a signal representing an image of the tissue with light in the third spectral band;
Digital capture and storage for storing a signal representative of the image of the tissue sample formed by the light in the first spectral band, the light in the second spectral band, and the light in the third spectral band With the device;
A video display having at least three color inputs, whereby a first output , a second output , and a third output are respectively light within the first spectral band, the second spectrum Ru is coupled to receive an image from the light in the spectrum band of light and the third in-band, comprises a video display apparatus. The apparatus of claim 1, wherein:
The light source output alternates between excitation light and white light within the time period of the video frame, and the resulting white and fluorescent images are captured separately and stored during each illumination period. And are simultaneously displayed on the video display.

Images