JP2001137172A - Fluorescence detection equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve diagnostic capability for discriminating tissue properties by changing setting conditions corresponding to the diagnosed site in biological tissue in fluorescence detection equipment. SOLUTION: In a fluorescence detection equipment comprising a light source section 100 that irradiates excited light with different wavelength on a biological tissue 1, image intake section 300 that detects each different wavelength band of fluorescence generated from the biological tissue 1, and computing section 400 that performs calculation based on the intensity of fluorescence for each different wavelength band, setting conditions of at least any one of the light source 100, image intake section 300 or computing section 400 are variable according to the diagnosed site of the biological tissue 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescence detection device, and more particularly to a fluorescence detection device which detects fluorescence emitted from a living tissue by irradiation with excitation light and performs diagnosis.

[0002]

2. Description of the Related Art Conventionally, a living tissue is irradiated with excitation light, and receives auto-fluorescence emitted from the living tissue by the irradiation of the excitation light. By analyzing the auto-fluorescence, a tissue state associated with various diseases can be detected. Diagnostic devices that identify changes are being studied.

[0003] Initially, a method of making a diagnosis based on a change in the intensity of autofluorescence emitted from a living tissue was attempted,
Due to the large number of error factors in the fluorescence intensity itself and the fact that sufficient diagnostic performance cannot be obtained with the intensity information alone, many of the current diagnostic devices have a profile of the spectral intensity distribution of autofluorescence emitted from living tissue. Attempts are being made to discriminate based on differences depending on changes in the state.For example, in a diseased tissue and a normal tissue, the ratio of the intensity in the green band wavelength region and the intensity in the red band wavelength region of the autofluorescence emitted from the tissue is determined. Noting that there is a large difference, the intensity of the green band wavelength region of the auto-fluorescence emitted from the living tissue to be diagnosed is divided by the intensity of the red band wavelength region, and the value is divided into normal tissue by another method in advance. By comparing the value of the living tissue determined as described above with a value obtained by the same method as above, it is determined whether the living tissue is a diseased tissue or a normal tissue, and a color image is obtained. System to be displayed as the JP-A-6-5
No. 4792.

[0004] The present applicant also discloses in Japanese Patent Application Laid-Open No. Hei 10-225436 a normalized intensity in which the intensity of a specific wavelength region in the autofluorescence is normalized by the intensity of the fluorescence over the entire wavelength region.
A method for identifying whether a tissue is a diseased tissue or a normal tissue and displaying the image as an image by comparing the normalized tissue strength determined by the same method as described above from a living tissue previously determined to be a normal tissue by another method. Has been proposed.

Further, the fluorescence yield, which is the ratio of the intensity of the excitation light irradiated to the diagnostic site of the living body and the intensity of the auto-fluorescence generated from the diagnostic site of the living body due to the irradiation of the excitation light, is calculated as follows:
A method of discriminating between a normal tissue and a diseased tissue by performing an arithmetic operation using the value of the normalized intensity is also considered.

[0006]

However, fluorescence diagnosis of a living body is not performed for one specific organ, but is performed for different organs such as trachea, esophagus, lung, stomach, duodenum, small intestine, and large intestine. Diagnosis is also performed on living organs. There is almost no difference between organs in the normalized fluorescence intensity profile obtained by normalizing the intensity distribution of the fluorescence spectrum in the normal tissue. Furthermore, the change in the normalized fluorescence profile from normal tissue to cancer tissue has little difference among organs. However, the fluorescence yield varies greatly between organs. Furthermore, the fluorescence yield changes when the wavelength region of the excitation light changes, and the manner of the change differs depending on the organ.

[0007] In other words, these different organs have a condition for generating fluorescence that more accurately reflects the characteristic of each tissue property (characteristic for distinguishing between normal tissue and diseased tissue). Even if the diagnosis is performed under the optimal setting conditions for identifying the tissue properties (the wavelength range of the excitation light, the wavelength range for detecting the fluorescence, or the conditions such as the arithmetic expression for identifying the tissue properties), other diagnosis may be performed. In some cases, the setting conditions are not optimal for the diagnosis of the tissue properties of the organ, and even if one device is used to diagnose different parts of the living body, the identification result of the tissue properties of the living body becomes inaccurate. There is a problem that an error occurs in which the diseased tissue is identified as a normal tissue.

[0008] The above problem is not limited to diagnosis using auto-fluorescence generated by irradiating living tissue that has not been subjected to any treatment with excitation light, but also to living tissue that has previously absorbed a fluorescent diagnostic agent. This is a common problem in diagnosis using fluorescence emitted by irradiating light.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a fluorescence detecting apparatus capable of enhancing the diagnostic ability for identifying tissue characteristics by changing setting conditions according to a diagnostic site of a living tissue. The purpose is to provide.

[0010]

According to the present invention, there is provided a fluorescence detecting apparatus for irradiating living tissue with light in a different wavelength region by excitation light irradiating means, and irradiating the fluorescence emitted from the living tissue by the excitation light with different wavelengths. What is claimed is: 1. A fluorescence detection device comprising: a fluorescence detection unit for detecting each region; and a calculation unit for performing a calculation based on the detected fluorescence intensity for each of different wavelength regions. The apparatus further comprises a setting condition changing means for changing at least one setting condition of the means according to a diagnosis site of a living tissue.

[0011] The setting condition changing means may further change the setting condition according to a risk factor of the living tissue.

The output of the calculating means can be displayed as an image together with a normal image of the living tissue.

Note that "changing the setting conditions of the excitation light irradiating means" means changing the wavelength region or intensity of the excitation light.

"Changing the setting conditions of the fluorescence detecting means" means changing the wavelength region or intensity for detecting fluorescence.

Also, "changing the setting condition of the calculating means"
Means that the expression, coefficient or threshold value of the operation is changed.

The risk factors are gender, age,
It refers to factors related to diagnosis, such as medical history, smoking status, Helicobacter pylori infection or treatment.

Further, the normal image means an image obtained by capturing an image of a diagnosis target portion illuminated with white light.

[0018]

According to the fluorescence detecting apparatus of the present invention, there is provided a setting condition changing means for changing at least one of the setting conditions of the excitation light irradiating means, the fluorescence detecting means and the calculating means in accordance with the diagnosis site of the living tissue. By providing this, the tissue properties of different organs were conventionally diagnosed under the same setting conditions, and the tissue properties could not be identified with sufficient diagnostic ability. Since it can be changed so that the irradiation of excitation light, the detection of fluorescence, or the calculation can be performed, the tissue properties of the part to be diagnosed can be more accurately identified.

Furthermore, by changing the set conditions according to the risk factors of the living tissue, it is possible to identify tissues that are highly likely to change due to factors such as age and smoking, which cannot be obtained only by fluorescence diagnosis. It can be performed more accurately.

Further, if an output of the arithmetic means is displayed as an image and display means for displaying the same part as the image together with a normal image is provided, the living organ to which the diagnostic part belongs can be easily confirmed by the normal image. This makes it possible to accurately change the setting conditions according to the diagnosis site.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a fluorescence endoscope in which a fluorescence detection device is applied to an endoscope as a first embodiment of the present invention.

As shown in FIG. 1, the fluorescent endoscope 800 irradiates the living tissue 1 with a light source unit 100 having a light source for excitation light and white light, and white light Wh guided from the light source unit 100.
A normal image (hereinafter, referred to as a normal image) illuminated by the irradiation of the white light Wh is captured, and the living tissue 1 is similarly irradiated with the excitation light Le guided from the light source unit 100. A bendable endoscope distal end portion 20 that propagates an image of generated fluorescence (hereinafter, referred to as a fluorescent image) through an optical fiber.
0, a normal image picked up by the endoscope end portion 200 is captured and stored as image data, and a fluorescent image propagated by the optical fiber is divided into a plurality of wavelength regions and imaged, and each corresponds to these wavelength regions. Image capturing unit 300 that stores fluorescent image data to be processed, an arithmetic unit 400 that performs an arithmetic operation on the fluorescent image data stored by the image capturing unit 300 to identify the tissue properties of the living tissue 1, and operates the fluorescent endoscope. Based on the data on the diagnostic site and the risk factor input by the user, the wavelength region of the excitation light Le applied to the living tissue 1, the wavelength region of the fluorescence detected by the image capturing unit 300, and the calculation performed by the calculation unit 400 It comprises a main part including a setting condition changing unit 500 for outputting a signal for setting an arithmetic expression to be used and a threshold value.

The white light source 19 of the light source unit 100 is controlled by the control unit 16 to generate white light W at a period of 1/60 second.
h, and the white light Wh is condensed by the white light condensing lens 22 and is incident on the white light guide 25-1 formed of glass fiber and connected to the light source unit.

On the other hand, a short wavelength laser light source 17-1 and a long wavelength laser light source 17-2 oscillating at different wavelengths are used as the excitation light sources of the light source unit 100. Light Le is generated. The excitation light Le-r generated from the short-wavelength laser light source 17-1 is reflected by the dichroic mirror 20, and is incident on an excitation light light guide 25-2 formed of a glass fiber and connected to the light source unit 100. On the other hand, the excitation light Le-s generated from the long wavelength laser light source 17-2 is reflected by the mirror 21, further passes through the dichroic mirror 20, and similarly enters the excitation light guide 25-2. It should be noted that the dichroic mirror 20 has the excitation light L
It has a characteristic of reflecting light in the wavelength region of er and transmitting light in the wavelength region of the excitation light Le-s.

The short-wavelength laser light source 17-1 has a wavelength of 4
The short-wavelength pump light Le-r near the wavelength of 05 nm is generated, and the long-wavelength laser light source 17-2 generates the long-wavelength pump light Le-s near the wavelength of 420 nm.
It may be fired at a different timing.

The white light guide 25-1 and the excitation light guide 25-2 are bundled.
It is integrated in a cable shape.

The endoscope end portion 200 holds the white light light guide 25-1 and the excitation light light guide 25-2 integrated in the above-mentioned cable shape, and is directed toward the living tissue 1 via the illumination lens 5. It is arranged so that the excitation light Le or the white light Wh is irradiated.

The image capturing section 300 has a CCD cable 2
An A / D converter for normal observation 8 for A / D conversion of an electrical image signal transmitted by 7 and a normal image memory 9 for storing the A / D converted image are provided for processing of a normal image. On the other hand, for processing of the fluorescent image, the fluorescent image guided to the end face Ko of the fluorescent image fiber 26 is imaged with high sensitivity by the fluorescent condenser lens 23 through the two rotary filters 28-1 and 28-2. An optical system that forms an image on a light receiving surface of the element 10, an A / D converter 11 for fluorescence observation that converts an electric image signal received and converted by the high-sensitivity imaging element 10 into a digital signal, and converts the signal into a digital signal And a fluorescent image memory 12 for storing the obtained image.

Each of the two rotary filters 28-1 and 28-2 is formed by combining a plurality of fan-shaped band-pass filters in a disk shape as shown in FIG. Reference numeral 1 denotes a wavelength region region fpc (400 nm to 425 nm) shown in FIG.
25 nm to 460 nm), fpk2 (460 nm to 52
0 nm), five fan-band filters Fpc, Fpk-1, Fpk-2, Fpk that transmit fpk3 (520 nm to 700 nm) and fpz (all wavelength regions), respectively.
pk-3, Fpz (Fpz is a transparent filter that transmits all wavelength ranges), is rotated by a P motor 29-1 in synchronization with the excitation light irradiation timing, and is transmitted through each fan-shaped band filter. A reflected image of light and a fluorescent image are captured by the high-sensitivity imaging device 10. Also,
The other rotating Q filter 28-2 has a wavelength region fqc (400 nm to 425 nm) shown in FIG.
1 (425 nm to 490 nm), fqk2 (490 nm
550 nm), fqk3 (550 nm to 700 nm)
And five fan-shaped bandpass filters Fqc, Fqk-1, Fqk-
2, Fqk-3, Fqz (Fqz is a transparent filter that transmits all wavelength ranges)
The reflected image and the fluorescence image of the excitation light rotated in synchronization with the excitation light irradiation timing and transmitted through each fan-shaped bandpass filter are captured by the high-sensitivity image sensor 10 by -2.

The fan-shaped bandpass filters Fpc and Fq for transmitting the excitation light in the wavelength range of 400 nm to 425 nm.
c has a light intensity attenuation characteristic that attenuates the intensity of the excitation light to the same level as the intensity of the fluorescence, and the fluorescence image and the reflection image of the excitation light received by the high-sensitivity imaging device 10 have the same intensity. An image is picked up in a light receiving intensity range suitable for the light receiving characteristics of the sensitivity image sensor 10.

When acquiring an image of a fluorescent image,
Rotation P based on a signal output from setting condition changing section 500
One of the filter 28-1 and the rotation Q filter 28-2 is selected and rotated, but the rotation filter that is not selected causes the reflection image of the excitation light and the fluorescence image to be captured with high sensitivity from the fluorescence condenser lens 23. It does not obstruct the optical path toward the element 10.

The arithmetic unit 400 includes a standardized image calculator 40 for obtaining standardized image data from the image data stored in the fluorescent image memory 12, and a fluorescent yield image data from the image data stored in the fluorescent image memory 12. , A tissue property image calculator 42 for obtaining tissue property image data indicating the tissue property of the living tissue 1 from the normalized image data and the fluorescence yield image data, and converting the tissue property image data to a lesion. An identification image calculator 43 for identifying the tissue region and the normal tissue region to obtain identification image data, and an identification image memory 44 for storing the identification image data are provided.

In the setting condition changing section 500, a combination of setting conditions such as the laser light source 17, the rotation filter 28, and the calculation method of the calculation section 400, which provides the highest diagnostic performance in accordance with the type of the living organ and the risk factor, is set. Based on the database memory 51 stored in advance and the information on the type and risk factor of the living organs inputted from the setting condition input key 60, the setting condition with the highest diagnostic performance is selected from the database memory 51, and the laser light source 17 is selected. ,
A diagnostic condition setting unit 50 for changing the operation method of the rotation filter 28 and the operation unit 400 is provided.

The normal image data stored in the normal image memory 9 of the image capturing unit 300 is input to the video signal processing circuit 14-1, converted into a video signal, and displayed by the normal image display 15-1. The identification image data stored in the identification image memory 44 of the arithmetic unit 400 is input to the video signal processing circuit 14-2, converted into a video signal, and displayed by the identification image display 15-2. The controller 16 controls the irradiation of the excitation light Le, the irradiation of the white light Wh, the synchronous control of the rotary filter, the timing of the imaging, the timing of the calculation, and the like.

Next, the operation of the above embodiment will be described. First, the type of the living organ to be diagnosed and the risk factor of the subject are input to the setting condition input key 60 by the operator of the fluorescent endoscope 800. The diagnostic condition setting device 50 refers to the database memory 51 based on the information input from the setting condition input key 60 so that a higher diagnostic performance can be obtained.
0 and the setting of the arithmetic unit 400 are changed.

Specifically, when the type of the living organ to be diagnosed is the organ V (for example, stomach), the short-wavelength laser light source 17-1 is selected as the excitation light source, and the rotating P
The filter 28-1 is selected. An arithmetic expression and a threshold value for obtaining a high diagnostic ability when diagnosing the organ V with the combination of the laser light source and the rotary filter are defined by a standardized image calculator 40, a fluorescence yield image calculator 41, and a tissue property image calculator 42. And input to the identification image calculator 43.

When the setting of these conditions is completed, the diagnosis by the fluorescence endoscope 800 is started, and the pulsed white light Wh and the pulsed white light Wh controlled by the controller 16 are controlled according to a timing chart as shown in FIG. The excitation light Le-r is emitted. The pulsed white light Wh emitted from the white light source 19 is transmitted through the white light condenser lens 22 and the white light guide 25-1 to the endoscope distal end portion 2.
The living tissue 1 is illuminated at a period of 1/60 second through the illumination lens 5 by being guided to 00. The image of the living tissue 1 illuminated by the white light Wh is formed on the light receiving surface of the normal observation CCD imaging device 7 by the normal observation objective lens 6, and is cycled by the normal observation CCD imaging device 7 for 1/60 second. Is imaged. These captured images are converted into image signals, read out, converted into digital values by the normal observation A / D converter 8, and stored in the normal image memory 9. And
The image data of the normal image stored in the normal image memory 9 is
The signal is input to the video signal processing circuit 14-1, converted into a video signal, and output to the normal image display 15-1 for display.

On the other hand, the short-wavelength pumping light Le- having a period of 1/60 second emitted from the short-wavelength laser light source 17-1.
The image of the fluorescence and the reflected image of the excitation light emitted from the living tissue 1 by the irradiation of r are imaged on the end face Ki of the fluorescence image fiber 26 by the fluorescence observation objective lens 4 and propagated to the other end face Ko. The fluorescence image and the reflected image of the excitation light propagated to the end face Ko are imaged on the light receiving surface of the high-sensitivity image sensor 10 by the fluorescent light condensing lens 23, and are imaged by the high-sensitivity image sensor 10.

Here, between the fluorescent light condensing lens 23 and the high-sensitivity image sensor 10, the rotating P filter 28-1 is rotated in accordance with the irradiation timing of the short-wavelength excitation light Le-r, and FIG. As shown in b), when the period is T1, a reflection image of the excitation light transmitted through the fan-shaped bandpass filter Fpc is captured, and when the imaging period is T2, the fan-shaped bandpass filter Fpk-
1 is captured, a fluorescent image transmitted through the fan-shaped bandpass filter Fpk-2 is taken at the imaging period T3, and a fan-shaped bandpass filter Fpk is taken at the imaging period T4.
-3 is captured, and a fan-shaped band filter Fpz is inserted between the fluorescent light condensing lens 23 and the high-sensitivity image sensor 10 at the imaging cycle T5. Not done. The rotation P filter 28-1 makes one rotation with the period from T1 to T5 as one period, and while the normal image is captured at 5 / frame at a period of 1/60 second (5/6
The rotating P filter 28-1 makes one rotation (during 0 seconds), and one frame of the reflected image of the excitation light and three frames of the fluorescence image are captured for each fan-shaped bandpass filter. Not an imaging target.

As shown in the timing chart of FIG. 4A, since both the normal image and the fluorescent image are captured every 1/60 second, the excitation light Le-r and the white light Wh are reduced by 1/60. Irradiation is performed in a pulse shape at a timing that does not overlap within 60 seconds.

When the rotation P filter 28-1 is selected, the rotation Q filter 28-2 is stopped,
A transparent fan-shaped bandpass filter F that transmits light in all regions
Since qz is fixed at a position crossing the optical path from the fluorescent light condensing lens 23 to the high-sensitivity imaging device 10, the rotary P filter 2
The action of 8-1 is not hindered.

The image data picked up by the high-sensitivity image pickup element 10 in each of the image pickup periods T1 to T4 is converted into an electric image signal, and further converted into a digital value by the A / D converter 11 for fluorescence observation. The image data of the reflection image of the excitation light Le-r transmitted through the fan-shaped band filter Fpc is Lrpv
(X, y), the image data of the fluorescent image transmitted through the fan band filter Fpk-1 is Krpv1 (x, y), and the image data of the fluorescent image transmitted through the fan band filter Fpk-2 is Kr
The image data of the fluorescent image transmitted through the pv2 (x, y) and the fan band filter Fpk-3 is stored in the fluorescent image memory 12 as Krpv3 (x, y).

Next, each image data stored in the fluorescent image memory 12 is input to the arithmetic section 400 and the following processing is performed to obtain identification image data.

First, each image data stored in the fluorescent image memory 12 is input to the standardized image calculator 40 and the fluorescence yield image calculator 41, and the standardized image data Kv (x,
y) and the fluorescence yield image data Cv (x, y) are obtained.

Then, these two image data are further input to the tissue property image calculator 42 to obtain tissue property image data SSv (x, y) indicating the tissue property of the imaged tissue.

The tissue property image data SSv (x, y) obtained in this way is further input to the identification image calculator 43, and the threshold value Qv selected according to the risk factor and each pixel (x, y) The comparison is performed for each y) to identify a normal tissue region and a diseased tissue region. Such identification is performed for all pixels of the tissue property image data SSv (x, y), and the image data is identified image data Sgv (x, y)
Is stored in the identification image memory 44.

The identification image data Sgv (x, y) stored in the identification image memory 44 is output to the video signal processing circuit 14-
2 and is converted into a video signal, which is used as information for diagnosing tissue properties associated with various diseases as the identification image display 15.
-2 is output and displayed. However, the image displayed on the identification image display 15-2 is an image updated every 5/60 seconds, and is not necessarily displayed as a complete moving image.

Here, the details of the diagnosis condition setting performed by the diagnosis condition setting device 50 will be described. As shown in FIG. 5, the fluorescence generated from the living tissue by the irradiation of the excitation light has a higher intensity in the normal tissue Sei than in the diseased tissue Byo, but is detected by a change in the angle and the distance at which the living tissue is irradiated with the excitation light. Since the value of the intensity of the fluorescent light also changes, if the intensity difference is used as a diagnostic index, the obtained result will be an unstable value. In the arithmetic unit 400, the living tissue is identified based on the normalized intensity and the fluorescence yield of the fluorescence which is hardly affected by the above.

First, the setting of the conditions for obtaining the normalized strength will be described. In the organ V of the living body, the short-wavelength excitation light L
The normalized intensity Sei1 of the fluorescence generated from the normal tissue and the normalized intensity Byo1 of the fluorescence generated from the diseased tissue by irradiating er (excitation light having a wavelength of 405 nm) are as follows:
For example, an intensity profile as shown in FIG. This profile has a wavelength of 460 nm to 520 nm.
(The transmission wavelength region of the filter Fpk-2), the intensity difference between the normalized intensity Sei1 of the normal tissue and the normalized intensity Byo1 of the diseased tissue is large.

Further, a long wavelength excitation light Le-s is applied to the organ V.
6 (excitation light having a wavelength of 420 nm), the normalized intensity Sei3 of the fluorescence generated from the normal tissue and the normalized intensity Byo3 of the fluorescence generated from the diseased tissue are shown in FIG.
FIG. 6 shows a profile as shown in FIG. 6B, which is obtained when the same organ V is irradiated with the short-wavelength excitation light Le-r.
This is different from the profile of the normalized intensity of fluorescence shown in (a).

The change in the normalized intensity profile of the autofluorescence of the normal tissue in the organ V and the normalized intensity profile of the autofluorescence of the diseased tissue in the organ V from that of the normal tissue also affects other organs such as the esophagus and the large intestine. The same is true. This tendency is the same even when the excitation wavelength is changed. Even when the excitation wavelength is changed, the changes in the normalized intensity profiles of the autofluorescence of the normal tissue and the diseased tissue are similar in the bronchus, esophagus, stomach and colon. However, the fluorescence yield (the ratio of the total fluorescence intensity to the excitation light intensity) differs depending on the organ and the excitation wavelength. Therefore, by changing the excitation wavelength and the threshold value of the fluorescence yield for distinguishing a normal tissue from a diseased tissue for each organ, it is possible to enhance the diagnostic ability for distinguishing a normal tissue from a diseased tissue.

That is, when diagnosing the organ V, the laser light source 17-1 and the rotary P filter 28-1 are selected, and the wavelength region fpk-2 (460 nm) is selected as shown in FIG.
By performing the calculation using the value of the normalized intensity of the fluorescence transmitted through (を 520 nm), whether the tissue is a normal tissue or a diseased tissue can be identified with higher discrimination ability.

The calculation for obtaining the standardized image data Kv (x, y) is performed by using the image data captured by the above setting and stored in the fluorescent image memory 12 as a standardized image calculator 40.
This is done by typing. That is, the normalized image data Kv
(X, y) represents the intensity of the fluorescence transmitted through the wavelength region fpk-2, the total wavelength region which is the sum of the intensity of the fluorescence transmitted through the wavelength region fpk-1, the wavelength region fpk-2, and the wavelength region fpk-3. Is calculated by the following equation divided by the intensity of fluorescence over

Kv (x, y) = Krpv2 (x, y) /
｛Krpv1 (x, y) + Krpv2 (x, y) + Kr
pv3 (x, y)｝ The value obtained by the above equation is the intensity ratio between the fluorescent light emitted from the same part of the living tissue, and the received light intensity of the fluorescent light changes depending on the change in the angle and the distance at which the excitation light irradiates the living tissue. Even though the ratio does not change, the value is hardly affected by the change in the intensity of the received fluorescence.

On the other hand, the value of the fluorescence yield Cv (x, y) obtained by the fluorescence yield image calculator 41 depends on the intensity of the excitation light applied to the diagnosis site of the living body and the intensity of the living body by the irradiation of the excitation light. This is a ratio with the intensity of the fluorescence generated from the diagnostic site, and is determined by dividing the intensity of the fluorescent image by the intensity of the reflected image of the excitation light without setting a specific wavelength region. That is, Cv (x, y) = ｛Krpv1 (x, y) + Krpv
2 (x, y) + Krpv3 (x, y)｝ / Lrpv
(X, y).

This value is also determined by the intensity ratio between the intensity of the excitation light and the intensity of the fluorescence generated by the irradiation of the excitation light. This value is difficult to receive. In addition,
Originally, this value is the intensity of the excitation light applied to the living tissue,
This value is obtained by dividing the intensity of the fluorescence generated by the irradiation of the excitation light.However, since it is difficult to directly measure the irradiation intensity of the excitation light, the value obtained by imaging the reflection image of the excitation light is used. The irradiation intensity of the excitation light is used instead.

The above Kv (x, y) and Cv (x,
The value of y) becomes larger as the value obtained from a living tissue closer to a normal tissue.

The fluorescence yield or normalized intensity obtained as described above can be used alone to discriminate between a normal tissue and a diseased tissue. However, in order to further enhance diagnostic performance, an operation combining the two is necessary. Tissue property image calculator 4
2, the tissue property image data SSv (x, y)
Is required. That is, SSv (x, y) = G1 × Kv (x, y) + G2 × Cv
Tissue property image data is obtained by calculation based on the expression (x, y).

The coefficients G1 and G2 used in this equation are coefficients for weighting the fluorescence yield and the normalized intensity, and a larger value is given to a term that is more important. Further, SSv (x, y) is set so as to become larger as the tissue properties of the normal tissue become closer.

The tissue property image data obtained by the above equation is compared with the threshold value Qv to identify a normal tissue area and a diseased tissue area. Depending on the risk factors, for example, older subjects with smoking habits are more likely to change their biological tissues than younger subjects without smoking habits. The value of the threshold Qv-o for identifying a normal tissue is larger than the value of the threshold Qv-y for identifying a living tissue of a subject who is young and has no smoking habits as a normal tissue.

Therefore, when the tissue property image data of an elderly subject who has a smoking habit is identified by the threshold Qv-y value for a young subject who does not have a smoking habit, the diseased part is shown in FIG.
(A) is displayed as an image as shown in BYO-1, but is a threshold Qvo for a subject who is elderly and has a smoking habit.
When the discrimination is performed by the value of, the diseased tissue becomes B in FIG.
The images are displayed as shown in YO-2 and BYO-3. In other words, BYO-2 indicates that the area diagnosed as a diseased tissue also expanded around BYO-1 due to the risk factors of aging and smoking habits.
-3 indicates that the tissue, which was young and was not identified as a diseased tissue without smoking habits, was now identified as a diseased tissue by the risk factors of elderly and smoking habits.

As described above, the value of the threshold value Q is changed according to the factor of the risk factor, and the wavelength region of the excitation light, the wavelength region of the fluorescent light to be detected, and
The operation formula of 00 is changed. Of these, the setting that is changed during diagnosis is the type of living organ and the presence or absence of treatment, which is one of the risk factors. When continuously diagnosing various parts of the living body, the type of living organ and Information on the presence or absence of the treatment is sequentially input to the diagnostic condition setting device 50 via the setting condition input key 60, and the type of the laser light source, the type of the rotation filter, the standardized image calculator 40, the fluorescence yield calculator 41, and the tissue properties Diagnosis is performed while changing the arithmetic expression of the image arithmetic unit 42 or the value of the threshold value Q one after another.

For example, when diagnosing the organ W following the diagnosis of the organ V, the operator of the fluorescent endoscope inputs the information on the change of the diagnostic organ to the diagnostic condition setting device 50 via the setting condition input key 60 and receives the information. The setting conditions are changed. That is,
A long-wavelength laser light source 17-2 that emits an excitation light Le-s as an excitation light source so as to enhance diagnostic capability for the organ W.
Is selected, and a rotation Q filter 28- is used as a rotation filter.
2 is selected. The arithmetic expression used in the arithmetic unit 400 is also changed as follows.

As described above, the image data of the reflection image of the excitation light transmitted through the fan-shaped bandpass filter Fqc is represented by Lsqw (x,
y), the image data of the fluorescent image transmitted through the fan band filter Fqk-1 is Ksqw1 (x, y), and the image data of the fluorescent image transmitted through the fan band filter Fqk-2 is Ksqw2.
Assuming that the image data of the fluorescence image transmitted through (x, y) and the fan band filter Fqk-3 is Ksqw3 (x, y), two types of normalized intensity image data Kw1 and Kw2 are obtained by the following equations.

Kw1 is a value obtained by normalizing the region of the wavelength region fqk-2 by the intensity of the entire wavelength region. Kw1 (x, y) = Ksqw2 (x, y) / ｛Ksqw
1 (x, y) + Ksqw2 (x, y) + Ksqw3
Kw2 obtained by the equation (x, y) is a value obtained by normalizing the wavelength region fqk-3 with the intensity of the entire wavelength region, and Kw2 (x, y) = Ksqw3 (x, y) / ｛Ksqw
1 (x, y) + Ksqw2 (x, y) + Ksqw3
(X, y)}.

The fluorescence yield image data Cw is obtained by the following equation in the same manner as described above.

Cw (x, y) = ｛Ksqw1 (x, y
y) + Ksqw2 (x, y) + Ksqw3 (x, y)}
/ Lsqw (x, y) and the tissue property image data SSw (x, y)
Is determined by the following equation, unlike when the diagnosis is made.

SSwv (x, y) = Gw1 × Kw1
(X, y)-Gw2 x Kw2 (x, y) + Gw3 x C
w (x, y) Furthermore, the threshold value used in the discrimination image calculator 43 is also Q
is changed to w. As described above, since the setting conditions are sequentially changed according to the type of the organ to be diagnosed and the like, high diagnostic performance can be maintained.

As described above, the fluorescence detecting device of the present invention
Since the setting conditions are changed so as to obtain an optimal diagnosis result in accordance with the risk factors such as the living organ and the presence / absence of treatment, diagnosis can be performed with high diagnostic ability.

It is to be noted that a normal image displayed on the normal image display unit 15-1 is used to determine to which living organ the diagnostic site belongs or whether the site is a treated tissue.

Further, when various parts of the living body are continuously diagnosed,
Image data that spans tissues having two or more different tissue properties is obtained at the boundary of a living organ or in the vicinity of a treated tissue, for example, but is generated from normal tissue as shown in FIG. The profile of the normalized intensity of the fluorescence hardly changes depending on the wavelength region of the excitation light and the type of the living organ, and only the profile of the normalized intensity of the fluorescence generated from the diseased tissue changes significantly. Based on the standardized intensity profile, a tissue having a standardized intensity profile of fluorescence different from that of the standard can be identified as a diseased tissue. Diagnosis at the same setting conditions across sites at the same time does not significantly reduce the diagnostic performance, and may cause the diseased tissue to be erroneously identified as normal tissue. Most does not occur with.

The correspondence relationship between the living organ and the risk factor and the setting condition is not limited to the above embodiment. The threshold may be changed depending on the type of the living organ, or the wavelength range of the excitation light may be changed depending on the risk factor other than the presence or absence of treatment. The detection wavelength region and the arithmetic expression may be changed. Further, the setting conditions can be changed in the unit of tissue instead of the living organ.

Further, the identification of the tissue properties is not limited to two types of normal tissue and diseased tissue, and the degree of progress of the lesion is classified into three or more types such as “cancer, ulcer, inflammation, dysplasia, and normal”. However, identification can also be performed by setting a threshold value for each.

The database memory can further accumulate data based on the diagnosed cases and update the set contents of the diagnostic conditions so that a diagnosis with higher diagnostic ability can be performed.

The basis of the diagnosis is the fluorescence yield image data and the normalized intensity image data. The ratio between the intensity of the fluorescence in the green wavelength region and the intensity of the fluorescence in the red wavelength region or the white light. The image data or the like obtained by performing image processing on the illuminated color image may be subjected to arithmetic processing in addition to the image data used by the arithmetic unit.

The number of excitation light sources and the number of rotary filters are not limited to two, but may be three or more. Further, the number of fan-shaped band filters constituting the rotary filter and the wavelength region thereof are not limited to the above-described embodiment, either.
Further, it is also possible to detect fluorescence obtained by simultaneously irradiating a plurality of excitation lights to a living tissue and use it as image data to be used for diagnosis.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a fluorescent endoscope according to an embodiment of the present invention.

FIG. 2 is a diagram showing a structure of a rotary filter.

FIG. 3 is a diagram showing transmission wavelength characteristics of a fan-shaped band filter constituting a rotary filter.

FIG. 4 is a diagram showing a relationship between a timing chart when imaging is performed and a filter at that time.

FIG. 5 is a diagram showing an intensity distribution of fluorescence generated from a normal tissue and a diseased tissue.

FIG. 6 is a diagram showing a change in normalized intensity of fluorescence depending on a biological organ and a wavelength region of excitation light.

FIG. 7 is a diagram showing a difference in a region identified as a diseased tissue based on a difference in a risk factor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Living tissue 4 Fluorescent observation objective lens 5 Illumination lens 6 Normal observation objective lens 7 Normal observation CCD imaging device 8 Normal observation A / D converter 9 Normal image memory 10 High-sensitivity imaging device 11 Fluorescence observation A / D Converter 12 Fluorescent image memory 14-1 Video signal processing circuit 14-2 Video signal processing circuit 15-1 Normal image display 15-2 Identification image display 16 Control unit 16 17-1 Short wavelength laser light source 17-2 Long wavelength Laser light source 19 White light source 20 Dichroic mirror 21 Mirror 21 22 White light focusing lens 23 Fluorescent focusing lens 25-1 White light light guide 25-2 Excitation light light guide 26 Fluorescence image fiber 27 CCD cable 28-1 Rotation P filter 28-2 Rotation Q filter 29-1 P motor 29-2 Q motor 4 Normalized image arithmetic unit 41 Fluorescence yield image arithmetic unit 42 Tissue property image arithmetic unit 43 Identification image arithmetic unit 44 Identification image memory 50 Diagnostic condition setting unit 51 Database memory 60 Setting condition input key 100 Light source unit 200 Endoscope tip 300 Image capturing unit 400 Operation unit 500 Setting condition changing unit 800 Fluorescence endoscope Wh White light Le Excitation light Le-r Excitation light Le-s Excitation light Fpc Fan band filter Fqc Fan band filter Ki End surface Ko End surface

Continued on the front page F term (reference) 2G043 AA03 BA16 CA03 EA01 FA01 FA06 GA04 GB01 GB03 GB05 GB19 GB21 HA01 HA05 JA03 KA09 LA03 NA01 NA06 4C061 AA01 BB02 BB08 LL02 NN01 NN05 PP08 QQ02 QQ04 QQ07 RR03 RR26 SS11

Claims (3)

[Claims] An excitation light irradiating means for irradiating a living tissue with light in a different wavelength range; a fluorescence detecting means for detecting fluorescence emitted from the biological tissue by the irradiation of the excitation light for each different wavelength range; Operating means for performing an operation based on the detected intensity of the fluorescence for each of the different wavelength regions, wherein at least one of the excitation light irradiating means, the fluorescence detecting means and the operating means is set. And a setting condition changing means for changing the setting according to a diagnosis site of the living tissue. 2. The fluorescence detecting apparatus according to claim 1, wherein said setting condition changing means further changes said setting condition according to a risk factor of said living tissue. 3. The fluorescence detection device according to claim 1, further comprising a display unit that displays an output of the calculation unit together with a normal image of the living tissue as an image.