JP3574591B2 - Electronic endoscope device for fluorescence diagnosis - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electronic endoscope apparatus for fluorescence diagnosis that images the inside of a body cavity based on autofluorescence emitted from a living body and outputs image data used for diagnosis of whether the living body is normal or abnormal. About.
[0002]
[Prior art]
It is known that when a living body is irradiated with excitation light of a specific wavelength, the living body emits fluorescence (this fluorescence is called “autofluorescence”). Furthermore, since the intensity of the autofluorescent green light region is lower at the abnormal part (tumor, cancer) of the living body than at the normal part, when represented as an image, the abnormal part may be displayed darker than the normal part. Are known.
[0003]
Based on this knowledge, the world's pioneering professor, Professor Haruhumi Kato of Tokyo Medical University, captured the autofluorescence of a living body and created an autofluorescence image that was used to diagnose whether the living body was normal or abnormal. An electronic endoscope apparatus for fluorescent diagnosis to be displayed was proposed, and based on this proposal, the applicant of the present invention has proceeded with the development, and as a result, an example has been disclosed in Japanese Patent Application Laid-Open No. 9-70384. is there.
[0004]
In the electronic endoscope apparatus for fluorescence diagnosis disclosed in this publication, it is considered that the auto-fluorescence is very weak light, and between the objective optical system and the imaging device at the tip of the electronic endoscope, An image intensifier that amplifies autofluorescence is provided. Therefore, according to the fluorescence diagnostic electronic endoscope, an image of the autofluorescence amplified by the image intensifier is picked up by the imaging device, so that a bright autofluorescence image can be obtained.
[0005]
[Problems to be solved by the invention]
However, when the image intensifier is incorporated in the distal end portion of the electronic endoscope, the outer diameter of the distal end portion becomes large. Since the distal end is a part to be inserted into the body cavity of the patient, there is a problem that if the distal end is too thick, a burden is imposed on the patient. Further, since the image intensifier is relatively expensive, there is also a problem that if the image intensifier is incorporated into the distal end portion of the electronic endoscope, the cost of the entire fluorescence diagnostic electronic endoscope apparatus increases.
[0006]
An object of the present invention is to provide an electronic endoscope apparatus for fluorescence diagnosis that can obtain an appropriate fluorescence diagnosis image without using an image intensifier.
[0007]
[Means for Solving the Problems]
The present invention has the following features to attain the object mentioned above.
[0008]
That is, the invention of claim 1 is: It has an illumination device that switches between visible band illumination light and ultraviolet band excitation light and irradiates the living body with the visible band illumination light. Irradiated The normal observation image of the living body and the Excitation light Said Caused by irradiating the living body The biological Auto fluorescence image Respectively An imaging device for imaging; A luminance region higher than a first threshold value is extracted from the normal observation image, a luminance region lower than a second threshold value is extracted from the autofluorescence image, and a region extracted from the normal observation image is extracted from the autofluorescence image. The area included in the extracted area is set as the specific area A detection unit for detecting, and a display control device for outputting an image signal indicating the specific area. And An electronic endoscope apparatus for fluorescence diagnosis comprising:
[0009]
With this configuration, the detection unit But special Since the constant region is extracted and the display control device outputs an image signal indicating the specific region, an image indicating the shape and position of the specific region can be displayed on a display device such as a CRT or a liquid crystal display. Therefore, if the luminance range of the specific region extracted by the detection unit is set to a range to which the luminance of the autofluorescence emitted from the abnormal part of the living body belongs, the abnormal part is displayed as the specific region. For this reason, even if it does not have an image intensifier, an appropriate image for fluorescence diagnosis can be provided to the user (doctor, etc.) of the electronic endoscope apparatus for fluorescence observation, and the user can appropriately generate the autofluorescence. Based diagnosis can be made.
[0010]
Here, the detection unit and the display control device can be configured as a function by executing a program of a CPU (central processing unit), for example, and can also be configured as an LSI, an ASIC, or the like.
[0013]
Claims 2 According to the invention described above, the display control device according to claim 1 is specified by outputting an image signal for displaying a fluorescence observation image in which only the specific region is displayed in a predetermined color. With this configuration, if there is an abnormal site in the living body as the subject, the abnormal site is displayed as a specific region in a predetermined color in the fluorescence diagnostic image. For this reason, the user of the apparatus can easily diagnose whether or not the part is abnormal.
[0014]
Claims 3 The invention described in the claims 1 Display control device, only the specific region of the normal observation image single The image is specified by outputting an image signal for displaying a fluorescence observation image which is shown in color and shows a color other than the specific area in color. The whole fluorescence observation image may be displayed in monochrome, or a region other than the specific region may be displayed in a pseudo color. However, if the configuration is such that only the specific area is displayed in a predetermined color and the area other than the specific area is displayed in color, diagnosis becomes easier.
[0015]
Claims 4 The invention described in the claims 3 The imaging device, while irradiating the living body sequentially red, green, and blue illumination light by the illumination device, respectively captures a normal observation image of the living body when each illumination light is irradiated, the display The control device synthesizes a color image based on the normal observation image of the living body when each of the illumination lights is irradiated, and generates a specific region image in which only the specific region is extracted from the autofluorescent image, The image is specified by outputting an image signal for displaying a fluorescence observation image obtained by superimposing the specific region image on a color image.
[0016]
Claims 5 The invention described in the claims 4 Is output by outputting an image signal for simultaneously displaying the color image and the fluorescence observation image. With this configuration, the user can compare and observe the two images, so that normal / abnormal diagnosis of the living body can be easily performed.
[0017]
Claims 6 The invention described in the claims 1 Is output by outputting an image signal for displaying the normal observation image as a moving image.
[0018]
Claims 7 The invention described in the claims 6 , An image signal for displaying only the normal observation image and an image signal for simultaneously displaying the normal observation image and the fluorescence diagnostic image are switched by the operator to the display control device. The switch is further provided with a switch for generating a switching signal for the determination.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Configuration of electronic endoscope device)
FIG. 1 is a schematic configuration diagram of an electronic endoscope apparatus for fluorescence observation (hereinafter, simply referred to as “electronic endoscope apparatus”) 10 according to the present embodiment. In FIG. 1, an electronic endoscope device 10 includes an electronic endoscope 11, a light source device 12 and a video processor 13 connected to the electronic endoscope 11, and a personal computer (PC) 14 connected to the video processor 13. And a monitor 15. Hereinafter, each of these devices will be individually described.
[0020]
Although only the insertion portion 16 is shown in FIG. 1 in the electronic endoscope 11, in actuality, a dial for operating a bending portion provided near the distal end of the insertion portion and various operation switches are provided. It is composed of various components, such as an operating unit provided, a flexible light guide tube connected to the light source device 12, and the like. The insertion portion 16 shown in FIG. 1 is a part to be inserted into a body cavity of a living body as a subject, and at least two through holes are formed at the tip of the insertion portion 16 along the axial direction. A tip (not shown) made of a hard member is fixed.
[0021]
An objective optical system 18 and a light distribution lens 21 are inserted into openings of the two through holes on the distal end side of the insertion portion 16, respectively. The objective optical system 18 is an imaging optical system that forms an image of a subject, and a cut-off filter 19 and a solid-state imaging device (CCD) 17 are fixed in this order (behind the base end). . When the subject is irradiated with excitation light (ultraviolet light) for exciting autofluorescence, the cutoff filter 19 shields the excitation light reflected on the subject surface and transmitted through the objective optical system 18. The CCD 17 is arranged at a position where an object is imaged by the objective optical system 18 and is connected to the video processor 13 via a signal line 17a. An image signal obtained by the CCD 17 capturing a subject image by the objective optical system 18 is input to the video processor 13 via the signal line 17a and processed by the video processor 13.
[0022]
On the other hand, on the proximal end side of the light distribution lens 21, a light guide fiber bundle (hereinafter, “light”) passed through the insertion section 16 through a light guide flexible tube (not shown) of the electronic endoscope 11 and an operation section. 20 (referred to as “guide”). Since the incident end face of the light guide 20 is disposed inside the light source device 12, the light guide 20 transmits the illumination light supplied from the light source device 12 to the distal end of the insertion section 16. The illumination light emitted from the emission end face of the light guide 20 is expanded by the light distribution lens 21 to illuminate the imaging range of the objective optical system 18 and the CCD 17.
[0023]
The light source device 12 is a device that supplies illumination light to the light guide 20, and a white light source 22 is provided therein. The white light source 22 includes a lamp that emits white light as illumination light for normal observation, and a reflector that converges the white light emitted from the lamp. Since the incident end face of the light guide 20 is arranged at a position where the white light is converged on the optical axis of the reflector of the white light source 22, the illumination light emitted from the white light source 22 efficiently transmits the light guide 20. Incident on.
[0024]
In the middle of the optical path of the illumination light between the light guide 20 and the white light source 22, an RGB rotation filter 23 is arranged. The RGB rotation filter 23 has three color filters of R (red), G (green), and B (blue), which have a fan-shaped planar shape at an equal angle and are arranged with a light shielding portion therebetween. And is rotated at a constant speed by a motor (not shown). Therefore, each color filter incorporated in the RGB rotation filter 23 is repeatedly inserted into the optical path of the illumination light emitted from the white light source 22 in the order of R, G, and B. As a result, the respective illumination lights of the R light, the G light, and the B light are repeatedly incident on the incident end face of the light guide 20, emitted from the distal end of the insertion portion 16 through the light guide 20, and transmitted through the light distribution lens 21. Illuminate the subject. Then, the image of the subject illuminated by each illumination light by the objective optical system 18 (that is, the subject image) is captured by the CCD 17, and the video processor 13 synthesizes the image as a color image. In this manner, the image is captured by the so-called RGB plane sequential method.
[0025]
Further, inside the light source device 12, a light source (UV light source) 24 composed of a lamp for emitting ultraviolet light as excitation light for auto-fluorescence and a reflector for converging the excitation light emitted from the lamp, and this UV light source A first mirror 25 and a second mirror 26 for guiding the excitation light emitted from the light guide 24 to the incident end face of the light guide 20 are provided. The first mirror 25 is arranged outside the optical path of the excitation light emitted from the UV light source 24 during normal observation, and inserted into the optical path of the excitation light during fluorescence diagnosis, and reflects the excitation light toward the second mirror 26. I do. The second mirror 26 is arranged outside the optical path of the illumination light emitted from the white light source 22 at the time of normal observation, and inserted into the optical path of the illumination light between the RGB rotation filter 23 and the light guide 20 at the time of fluorescence diagnosis. As a result, the illumination light from the white light source 22 is shielded, and the excitation light reflected by the first mirror 25 is reflected toward the incident end face of the light guide 20. With the above configuration, illumination light (R light, G light, and B light) passing through the RGB rotation filter 23 enters the incident end face of the light guide 20 during normal observation, and excitation light emitted from the UV light source 24 during fluorescence diagnosis. The light enters the incident end face of the light guide 20.
[0026]
Further, the light source device 12 includes a light source control unit 27. The light source control unit 27 adjusts the amount of illumination light or excitation light incident on the light guide 20 according to, for example, an instruction from the PC 14, and controls the white light source 22, the RGB rotation filter 23, the first mirror 25, and the second mirror. 26 is controlled. In addition, the light source control unit 27 gives the PC 14 a signal (synchronization signal) indicating the timing at which each of the RGB color filters passes through the optical path of the illumination light emitted from the white light source 22.
[0027]
The video processor 13 has a switch SW connected to the signal line 17a. The switch SW is a switch composed of two output terminals T1 and T2 and an input terminal that is electrically connected to a switch piece that can selectively contact each of the output terminals T1 and T2. As an electronic circuit equivalent to this switch. The switch piece of the switch SW contacts the output terminal T1 during normal observation, and contacts the output terminal T2 during fluorescence diagnosis. The output terminal T1 of the switch SW is connected to the input terminal of an analog / digital converter (A / D converter) 28.
[0028]
The A / D converter 28 converts the output signal (image signal) of the CCD 17 during normal observation from analog to digital, and outputs the signal to its output terminal. The output terminal of the A / D converter 28 is connected to the respective input terminals of the R memory 29, the G memory 30, and the B memory 31.
[0029]
The R memory 29 stores an image signal output from the CCD 17 when the subject is irradiated with the R light (referred to as an “R image signal”). The G memory 30 stores an image signal output from the CCD 17 when the subject is irradiated with G light (referred to as a “G image signal”). The B memory 31 stores an image signal output from the CCD 17 when the subject is irradiated with B light (referred to as a “B image signal”).
[0030]
On the other hand, the output terminal T2 of the switch SW is connected to the input terminal of the amplifier 32. The amplifier 32 amplifies an image signal (referred to as an “F image signal”) output from the CCD 17 at the time of fluorescence diagnosis and outputs the amplified signal to an output terminal thereof. The output terminal of the amplifier 32 is connected to the input terminal of the A / D converter 33. The A / D converter 33 converts the F image signal amplified by the amplifier 32 from analog to digital, and outputs it to its output terminal. The output terminal of the A / D converter 33 is connected to the input terminal of the F memory 34. The F memory 34 stores an F image signal output from the A / D converter 33.
[0031]
Output terminals of the R memory 29, the G memory 30, the B memory 31, and the F memory 34 are connected to a scan converter 36. Each output terminal of the scan converter 36 is connected to the PC 14. The scan converter 36 reads each of the RGB image signals stored in the R memory 29, the G memory 30, and the B memory 31 in accordance with the synchronization signal input from the PC 14, and synchronously outputs the image signals to the PC 14. . Similarly, the scan converter 36 reads out the F image signal from the F memory 34 according to the synchronization signal input from the PC 14 and outputs it to the PC 14.
[0032]
The video processor 13 has a microcomputer (MIC) 35. The MIC 35 is connected to the PC 14 and to an external switch 36 a provided outside the video processor 13. The MIC 35 is also connected to control terminals of the switch SW, the amplifier 32, the R memory 29, the G memory 30, the B memory 31, and the F memory 34. The MIC 35 selectively brings the switch piece of the switch SW into contact with one of the output terminal T1 and the output terminal T2 in accordance with a control command from the PC 14. The MIC 35 adjusts the amplification factor of the amplifier 32 according to a control command from the PC 14. The MIC 35 stores output signals from the A / D converters 28 and 33 in a corresponding one of the R memory, the G memory, the B memory, and the F memory according to the synchronization signal input from the PC 14.
[0033]
Further, the video processor 13 has a digital / analog converter (D / A converter) 37 connected to the PC 14. The D / A converter 37 converts the RGB image signal output from the PC 14 from digital to analog, and inputs the digital image to the monitor 15. Thus, an image of the subject based on the analog RGB image signal is displayed on the monitor 15.
[0034]
The PC 14 is a computer that further performs image processing on each image signal output from the video processor 13. As shown in detail in the block of FIG. 2, the PC 14 is connected to a CPU (Central Processing Unit) 38 connected to the light source control unit 27 of the light source device 12 and the MIC 35 of the video processor 13, and to the CPU 38. It comprises a video capture 39, a memory unit 40 and a VRAM (video RAM) 41.
[0035]
The video capture 39 temporarily stores the RGB image signals or the F image signals output from the scan converter 36 of the video processor 13 and inputs them to the memory unit 40 according to an instruction from the CPU 38.
[0036]
The memory unit 40 has an area of a memory M1 (mem_RGB) for storing RGB image signals output from the video capture 39 and an area of a memory MF (mem_FL) for storing F image signals output from the video capture 39. And a RAM (Random Access Memory), which is divided into an area of a memory M2 (mem_RGB2) used for a process of creating a fluorescence diagnostic image, and is used for processing by the CPU 38.
[0037]
The VRAM 41 holds data (RGB image signals) indicating contents to be displayed on the monitor 15 output from the CPU 38, and outputs the held RGB image signals to the D / A converter 37 according to an instruction from the CPU 38. .
[0038]
The CPU 38 controls the operations of the light source control unit 27, the MIC 35, the video capture 39, the memory unit 40, and the VRAM 41 by executing a control program stored in a ROM (Read Only Memory) not shown.
[0039]
Hereinafter, an operation example of the electronic endoscope apparatus including the respective devices having the above-described configuration will be described along processing by the CPU 38 of the PC 14.
[0040]
FIG. 3 is a flowchart showing a process (main routine) by the CPU 38, and FIG. 4 is a flowchart showing a subroutine of the fluorescence diagnostic image generation process executed in S8 of FIG. The process shown in FIG. 3 is started by turning on the main power of the light source device 12, the video processor 13, and the PC 14, respectively.
[0041]
After the start, first, the CPU 38 gives a control command for operating the light source device 12 in the normal observation state to the light source control unit 27 (S1). Then, the light source control unit 27 of the light source device 12 retracts the first mirror 25 outside the optical path of the excitation light emitted from the UV light source 24, and moves the second mirror 25 outside the optical path of the illumination light emitted from the white light source 22. 26 is retracted (see the broken line in FIG. 1). Subsequently, the light source control unit 27 turns on the white light source 22 and the UV light source 24 and rotates the RGB rotation filter 23. Then, the light source control unit 27 supplies a synchronization signal of the RGB rotation filter 23 to the CPU 38. The CPU 38 supplies the synchronization signal to the MIC 35 and the scan converter 36 (S2). Further, the CPU 38 gives a control command to the MIC 35 to bring the switch piece of the switch SW into contact with the output terminal T1 (S3). As a result, the MIC 35 brings the switch piece of the switch SW into contact with the output terminal T1.
[0042]
By performing the above-described control from S1 to S3, white illumination light is emitted from the white light source 22. The white illumination light passes through the RGB rotation filter 23, so that R light, G light, and B light are emitted. And the light is sequentially incident on the light guide 20. The illumination light of each color is transmitted to the distal end of the electronic endoscope 11 through the light guide 20, emitted from the emission end face of the light guide 20, and diffused by the light distribution lens 21, while the object (that is, the inner wall of the body cavity). Are sequentially illuminated.
[0043]
When the subject is sequentially illuminated with each illumination light, the reflected light from the subject forms an image of the subject on the imaging surface of the CCD 17 by the objective optical system 18, and the subject image is captured by the CCD 17. Then, image signals (R image signal, G image signal, B image signal) based on each illumination light are sequentially output from the CCD 17. Each image signal is input to the A / D converter 28 via the signal line 17a and the switch SW, is converted from analog to digital by the A / D converter 28, and is input to the input terminals of the memories 29, 30, and 31. At this time, the MIC 35 sequentially inputs control signals to the control terminals of the memories 29, 30, and 31 based on the synchronization signal from the CPU 38.
[0044]
When this control signal is input, each of the memories 29, 30, and 31 captures the image signal output from the A / D converter 28 at that time and holds the image signal until the next control signal is input. Keep doing. Therefore, the R image signal is stored in the R memory 29, the G image signal is stored in the G memory 30, and the B image signal is stored in the B memory 31. In this manner, each of the RGB image signals for one screen is stored in the R memory 29, the G memory 30, and the B memory 31, respectively. Then, the scan converter 36 reads the RGB image signals from the memories 29 to 31 and outputs them to the PC 14 in synchronization. The RGB image signals transmitted to the PC 14 in this manner are stored in the video capture 39 of the PC 14.
[0045]
Then, the CPU 38 sequentially writes the RGB image signals stored in the video capture 39 into the memory M1 of the memory unit 40 (S4). As a result, on the memory M1, a 24-bit RGB image signal (data of a normal observation image) in which each pixel is composed of an R image signal, a G image signal, and a B image signal each having an 8-bit luminance value is synthesized. You.
[0046]
Subsequently, the CPU 38 reads out the data (RGB image signals) of the normal observation image stored in the memory M1 and writes it into the VRAM 41 (S5). Subsequently, the CPU 38 outputs the RGB image signals stored in the VRAM 41 to the D / A converter 37 (S6). Then, the D / A converter 37 converts the RGB image signal output from the VRAM 41 from digital to analog, and supplies it to the monitor 15. As a result, as shown in FIG. 5, an image of the subject (living body) when illuminated by the illumination light, that is, a normal observation image is displayed in color in the display area on the left side of the monitor 15. In this embodiment, the VRAM 41 outputs an RGB image signal for one screen every 1/30 second, for example, and an image based on the image signal is displayed on the monitor 15. Therefore, the normal observation image is displayed as a moving image in the display area on the left side of the monitor 15.
[0047]
The above operation is an operation during normal observation. FIG. 5 shows a normal observation image including a tracheal tube cavity A and a tracheal tube wall B as a normal observation image of a subject. However, although the tumor region C is actually included in the tube wall portion B, the luminance distribution of the normal observation image is as shown in FIG. Almost indistinguishable.
[0048]
Next, the operation of the electronic endoscope apparatus 10 at the time of fluorescence diagnosis will be described.
[0049]
When the external switch 36a is turned on, the MIC 35 of the video processor 13 detects a signal (ON signal) generated by the turning on, and notifies the PC 14 (CPU 38) of the detection. On the other hand, each time the processing of S1 to S6 is completed, the CPU 38 determines whether or not there has been a notification that the ON signal has been detected from the MIC 35 (S7). If not, the process returns to S1. In S8, a fluorescence diagnostic image creation process is executed.
[0050]
FIG. 4 is a flowchart showing a fluorescence diagnostic image creation processing subroutine executed in S8. When entering this subroutine, the CPU 38 first stores data (RGB image signals) of the normally obtained normal observation image in the memory M1 (S101). Here, it is assumed that the data of the normal observation image substantially the same as that shown in FIG. 5 is stored in the memory M1.
[0051]
Subsequently, the CPU 38 gives a control command for operating the light source device 12 in the fluorescence observation state to the light source control unit 27 (S102). Then, the light source control unit 27 of the light source device 12 inserts the first mirror 25 into the optical path of the excitation light from the UV light source 24 and transmits the excitation light reflected by the first mirror 25 to the incident end face of the light guide 20. The second mirror 26 is moved to a position where the light is reflected toward. Subsequently, the CPU 38 gives a control command to the MIC 35 to bring the switch piece of the switch SW into contact with the output terminal T2 and activate the amplifier 32 (S103). Thereby, the MIC 35 brings the switch piece of the switch SW into contact with the output terminal T2 and supplies a control signal to the control terminal of the amplifier 32.
[0052]
By executing the control in S102 and S103, the excitation light emitted from the UV light source 24 is reflected by the first mirror 25 and the second mirror 26, and is incident on the light guide 20. The excitation light is transmitted to the distal end of the electronic endoscope 11 through the light guide 20, emitted from the emission end face of the light guide 20, and radiated to the subject while being diffused by the light distribution lens 21. Then, autofluorescence is emitted from the living tissue of the trachea, which is the subject. At this time, the intensity of the green light band component in the autofluorescence emitted from the normal part of the living tissue is higher than the intensity of the green light band component in the autofluorescence emitted from the tumor part C.
[0053]
The light from the subject including the reflected light of the autofluorescence and the excitation light enters the objective optical system 18 and passes through the cutoff filter 19. Since the cutoff filter 19 cuts light in the ultraviolet band, only the autofluorescent light component passes through the cutoff filter 19 and forms an image of the subject on the imaging surface of the CCD 17. Thus, the CCD 17 captures an image of the subject (living body) when the excitation light is irradiated, that is, an autofluorescence image. At this time, the intensity of the autofluorescence from the normal part of the living body is higher than the intensity of the autofluorescence from the abnormal part. Therefore, as shown in FIG. The amount of received light is larger than the amount of received light of the pixel that captured the image of the tumor site C. Then, the CCD 17 outputs an image signal (F image signal) corresponding to the amount of light received by each pixel.
[0054]
Thereafter, the F image signal is transmitted to the amplifier 32 through the signal line 17a and the switch SW, amplified by the amplifier 32, analog-digital converted by the A / D converter 33, and stored in the F memory 34. When the F image signal for one screen is stored in the F memory 34 in this manner, the scan converter 36 outputs the F image signal in the F memory 34 to the PC 14. As a result, the F image signal is stored in the video capture 39.
[0055]
Then, the CPU 38 stores the F image signal (data of the autofluorescent image) stored in the video capture 39 in the memory MF (S104). In this way, for substantially the same imaging range, the memory M1 stores the data of the normal observation image (RGB image signal), and the memory MF stores the data of the autofluorescent image (F image signal).
[0056]
Subsequently, the CPU 38 determines the luminance value of the R image signal, the luminance value of the G image signal, and the luminance of the B image signal for the same pixel in the RGB image signal (data of the normal observation image) stored in the memory M1 at this time. By performing a predetermined matrix operation on the value, a luminance value (a binary value represented by 8 bits) of the entire pixel is calculated (RGB-YCC conversion). The CPU 38 writes the calculated brightness values (Y signals) for all the pixels in the memory M2 (S105). As a result, in the image signal stored in the memory M2, as shown in FIGS. 5 and 6, the brightness of the tube cavity A is low, and the brightness of the tube wall B including the tumor site C is high.
[0057]
Next, the CPU 38 compares the luminance value of each pixel of the image signal stored in the memory M2 with a predetermined first threshold value (indicated by a broken line in FIG. 6) to binarize (S106). That is, the CPU 38 rewrites all eight bits representing the luminance value of the pixel whose luminance value is lower than the first threshold value to “0”. On the other hand, all eight bits representing the luminance value of a pixel having a luminance value higher than the first threshold value are rewritten to “1”. As a result, as shown in FIGS. 7 and 8, the tube cavity A and the tube wall B are separated, and only the pixel corresponding to the tube wall B has the luminance value “11111111”.
[0058]
By the way, an F image signal having a distribution of luminance values (binary values represented by 8 bits) as shown in FIG. 9 is stored in the memory MF. Therefore, the CPU 38 performs a logical product (AND) operation on the value of each bit constituting the luminance value of each pixel stored in the memory M2 and the value of each bit constituting the luminance value of each pixel stored in the memory MF. Is performed, and the calculation result is overwritten in the memory MF (S107). As a result, as shown in FIGS. 10 and 11, the portion corresponding to the tube space A in the F image signal is masked, and only the portion corresponding to the remaining tube wall B (including the tumor site C) is restored. Is held in the memory MF. The luminance value of the portion indicating the tube wall portion B in the image signal stored in the memory MF is higher in the normal portion than in the tumor portion C, as shown in FIG.
[0059]
Next, the CPU 38 compares the luminance value of each pixel of the image signal stored in the memory MF with a predetermined second threshold value (a value larger than the first threshold value as indicated by a broken line in FIG. 11), and The value is converted (S108). That is, the CPU 38 rewrites all eight bits representing the luminance values of pixels having luminance values in the β region and the γ region lower than the second threshold value to “0”. On the other hand, all the eight bits representing the luminance value of the pixel whose luminance value exists in the α region higher than the second threshold value are rewritten to “1”. As a result, only the normal part is extracted from the tube wall B, and only this normal part has the luminance value “11111111”.
[0060]
Next, the CPU 38 performs an exclusive OR operation on the value of each bit constituting the luminance value of each pixel stored in the memory M2 and the value of each bit constituting the luminance value of each pixel stored in the memory MF. , Overwrites the calculation result in the memory M2 (S109). As a result, as shown in FIGS. 12 and 13, an image signal indicating the shape and position of the tumor site C is stored in the memory M2.
[0061]
Subsequently, the CPU 38 writes the image signal (data of the normal observation image) stored in the memory M1 into the left area of the VRAM 41 (S110). Next, the CPU 38 combines the still image of the normal observation image and the image of the tumor site C determined based on the intensity of the autofluorescence (an image indicating a specific region including pixels belonging to the β region with a brightness value of β). (An image in which a specific area is superimposed in blue in a normal observation image) is generated. That is, the CPU 38 maps a pixel having a luminance value of “11111111” (a pixel belonging to the tumor site C) in the image signal stored in the memory M2 to the memory M1, and stores the mapped pixel on the memory M1. The color is set to, for example, B (blue) (S111). As a result, on the memory M1, still image data of the fluorescence diagnosis image in which the region corresponding to the tumor site C (abnormal site) in the normal observation image is shown in blue. Then, the CPU 38 writes the data of the fluorescence diagnostic image stored in the memory M1 into the right area of the VRAM 41 (S112). When the entire VRAM 41 is filled with the image data as described above, the CPU 38 outputs the contents stored in the VRAM 41 (image data indicating an image to be displayed on the monitor 15) to the D / A converter 37 (S113). .
[0062]
The contents stored in the VRAM 41 are supplied to the monitor 15 via the D / A converter 37. Accordingly, a still image of the fluorescence diagnostic image in which the tumor site C is shown in blue is displayed in the display area on the right side of the monitor 15.
[0063]
Thereafter, the CPU 38 gives a control command for operating the light source device 12 and the video processor 13 in the normal observation state to the light source control unit 27 and the MIC 35 (S114), and ends this subroutine. The MIC 35 that has received the control command of S114 brings the switch piece of the switch SW into contact with the output terminal T1. Further, the light source control unit 27 retracts the first mirror 25 and the second mirror 26 from the optical paths of the illumination light and the excitation light. As a result, the electronic endoscope apparatus 10 returns to the normal observation state, and the normal observation image displayed in the display area on the left side of the monitor 15 becomes a moving image, as shown in FIG.
(Example of use of electronic endoscope device)
Next, a usage example of the above-described electronic endoscope device 10 will be described. First, the operator of the electronic endoscope apparatus 10 turns on the power of the light source device 12, the video processor 13, the PC 14, and the monitor 15. Thereby, the CPU 38 of the PC 14 executes the main routine shown in FIG. 3, and the normal observation image of the subject is displayed in the display area on the left side of the monitor 15.
[0064]
Subsequently, the operator inserts the insertion section 16 of the electronic endoscope 11 into the body cavity, and searches for a site expected to be a tumor site C while observing the normal observation image displayed on the monitor 15.
[0065]
Thereafter, when a site expected to be a tumor site C is displayed on the monitor 15 (see FIG. 5), the operator turns on the external switch 36a. Then, the CPU 38 of the PC 14 executes the fluorescence diagnostic image generation processing shown in FIG. As a result, the fluorescence diagnostic image is displayed in the display area on the right side of the monitor 15.
[0066]
At this time, if there is a region displayed in blue in the fluorescence diagnostic image, it is highly likely that the site predicted to be the tumor site C is actually a tumor site, and if there is no region displayed in blue. Indicates that the site predicted as the tumor site C is likely to be a normal site. Then, based on the normal observation image and the image for fluorescence diagnosis, the operator makes a diagnosis as to whether or not the site expected to be the tumor site C is actually a tumor site.
[Effects of Embodiment]
According to the electronic endoscope apparatus 10 of the present embodiment, when the operator turns on the external switch 36a at a site expected to be the tumor site C, the CPU 38 of the PC 14 causes the CPU 38 of the PC 14 based on the difference in the intensity of the autofluorescence to autonomously. A tumor site C (a site consisting of pixels whose luminance value belongs to the β region) is extracted from the fluorescent image, and a fluorescent diagnostic image in which the tumor site C is displayed in blue is displayed on the monitor 15. For this reason, the operator can appropriately diagnose whether or not the site predicted to be the tumor site C is actually the main part.
[0067]
In addition, according to the electronic endoscope apparatus 10 of the present embodiment, a fluorescence diagnostic image appropriately indicating the tumor site C can be displayed on the monitor 15 without having an image intensifier. For this reason, the configuration of the electronic endoscope device 10 can be simplified, and the cost can be reduced. In particular, since it is not necessary to dispose the image intensifier at the distal end of the electronic endoscope, it is possible to prevent the distal end of the electronic endoscope from becoming too thick, thereby reducing the burden on the patient. it can.
[0068]
In the present embodiment, a fluorescence diagnosis image in which a region corresponding to a tumor site (a site whose luminance value belongs to the β region in the autofluorescence image) in the normal observation image stored in the memory M1 is shown in blue. Although the monitor 15 is configured to be displayed, a fluorescence diagnosis image in which a tumor site (a site whose luminance value belongs to the β region in the autofluorescence image) in the autofluorescence image stored in the memory MF is displayed in blue is monitored. 15 may be displayed.
[0069]
In this embodiment, the output signal of the CCD 17 at the time of the fluorescence diagnosis is configured to be amplified by the amplifier 32. However, the output signal of the CCD 17 may be amplified by using frame addition in addition to the amplifier 32.
[0070]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the electronic endoscope apparatus for a fluorescence diagnosis by this invention, even if it does not have an image intensifier, the image for an appropriate fluorescence diagnosis can be obtained and the structure of the electronic endoscope apparatus for a fluorescence diagnosis Can be simplified, and the cost can be reduced.
[0071]
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an electronic endoscope apparatus for fluorescence diagnosis according to an embodiment of the present invention.
FIG. 2 is a configuration diagram of a PC shown in FIG. 1;
FIG. 3 is a flowchart showing a main routine of processing by a CPU shown in FIG. 2;
FIG. 4 is a flowchart showing a fluorescence diagnostic image generation processing subroutine shown in FIG. 3;
FIG. 5 is a diagram showing a display example of a normal observation image.
FIG. 6 is a graph showing a luminance distribution in a normal observation image.
FIG. 7 is a diagram showing a display example of a normal observation image after binarization based on a first threshold value;
FIG. 8 is a graph showing a luminance distribution in a normal observation image after binarization based on a first threshold.
FIG. 9 is a graph showing a luminance distribution in an autofluorescence image.
FIG. 10 is a diagram showing a display example of an autofluorescence image after a logical product process;
FIG. 11 is a graph showing a luminance distribution in an autofluorescence image after the logical product processing;
FIG. 12 is a diagram illustrating a display example of an autofluorescence image after binarization based on a second threshold value;
FIG. 13 is a graph showing a luminance distribution in an autofluorescence image after binarization based on a second threshold.
FIG. 14 is a diagram showing an example of a screen displayed on a monitor.
[Explanation of symbols]
10. Electronic endoscope device for fluorescence diagnosis
11 Electronic endoscope
12 Light source device
13 Video Processor
14 Personal computer
17 CCD
36 External switch
38 CPU

Claims (7)

And has a lighting device for illuminating the living body by switching between the excitation light of the illumination light and ultraviolet bands of the visible spectrum, illuminating the normal observation image and the excitation light of the living body irradiated with illumination light of the visible band to the living body an imaging device for each of an image of the autofluorescence of the living body caused by,
A luminance region higher than a first threshold value is extracted from the normal observation image, a luminance region lower than a second threshold value is extracted from the autofluorescence image, and a region extracted from the normal observation image is extracted from the autofluorescence image. A detection unit that detects a region included in the extracted region as a specific region ,
Display control equipment that outputs an image signal indicative of the specific area
Preparative fluorescence diagnostic electronic endoscope apparatus comprising the. The electronic endoscope apparatus for fluorescence diagnosis according to claim 1, wherein the display control device outputs an image signal for displaying a fluorescence observation image in which only the specific region is displayed in a predetermined color. The display control device according to claim 1, characterized in that outputs an image signal for displaying the fluorescence observation image showing other than the specific region in color with showing only the specific area of the normal observation image in a single color An electronic endoscope apparatus for fluorescence diagnosis according to the above. The imaging device, by illuminating the living body in sequence with red, green, and blue illumination light by the illumination device, respectively captures a normal observation image of the living body when each illumination light is irradiated,
The display control device synthesizes a color image based on the normal observation image of the living body when each of the illumination lights is irradiated, and generates a specific region image in which only the specific region is extracted from the autofluorescence image. 4. An electronic endoscope apparatus for fluorescence diagnosis according to claim 3 , wherein an image signal for displaying a fluorescence observation image obtained by superimposing the specific area image on the color image is output. The electronic endoscope apparatus for fluorescence diagnosis according to claim 4 , wherein the display control device outputs an image signal for simultaneously displaying the color image and the fluorescence observation image. The display control device, the normal observation image fluorescence diagnostic electronic endoscope apparatus according to claim 1, wherein the outputting the image signal for displaying the videos. An image signal for displaying only the normal observation image and an image signal for simultaneously displaying the normal observation image and the fluorescence diagnostic image, which are operated by an operator, for switching the display control device. The electronic endoscope apparatus for fluorescence diagnosis according to claim 5 , further comprising a switch for generating a switching signal.

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