JP4846917B2 - Endoscope device for fluorescence observation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope apparatus for fluorescence observation that irradiates a subject to be examined containing a fluorescent substance with excitation light and obtains information on fluorescence emitted from the subject to be examined.
[0002]
[Prior art]
2. Description of the Related Art In recent years, various studies on photodynamic diagnosis generally referred to as PDD (Photodynamics Diagnostics) have been made. In this photodynamic diagnosis, a fluorescent agent that tends to accumulate in tumor tissue is administered to the subject, irradiated with excitation light, and a fluorescence image emitted from the fluorescent agent accumulated in the tumor tissue is observed. It is a technique for diagnosing a tumor portion by observing the presence or absence of a fluorescent image and its shape.
[0003]
In order to increase the contrast between the fluorescence of the fluorescent agent accumulated in the tumor tissue and the reflected light when the normal tissue is irradiated with the excitation light, a filter that transmits the excitation wavelength region on the light source side and a contrast on the imaging means side are provided. Japanese Patent Laid-Open No. 3-97439 discloses a fluorescence observation apparatus provided with a filter having a spectral transmission characteristic for enhancing.
[0004]
Japanese Patent Laid-Open No. 9-497 discloses a fluorescence observation apparatus provided with a plurality of filters on the imaging means side in order to obtain an optimum contrast.
Also, instead of manually switching between observation with ultraviolet light and normal light, irradiation is automatically switched between ultraviolet light and normal light at a preset time, making it possible to observe fluorescence in time series. A fluorescence observation apparatus is disclosed in JP-A-3-97439 and JP-A-6-125911.
[0005]
Further, Japanese Patent Laid-Open No. 6-125911 discloses a fluorescence observation apparatus that automatically performs image processing and displays a fluorescence image on a monitor when a fluorescence intensity equal to or higher than a set value is measured.
[0006]
[Problems to be solved by the invention]
However, with respect to claim 1, the conventional example has the following problems.
In order to increase the contrast between tumor tissue and normal tissue, Japanese Patent Application Laid-Open No. 3-97439 has filters on the light source side and the imaging means side, but due to variations in the spectral characteristics of the filter, the fluorescence of the tumor tissue is too weak to be observed. In some cases, the desired contrast may not be obtained because the reflected light from the normal tissue is too weak and it is difficult to confirm the state of the living body. In addition, it is difficult to obtain the desired contrast depending on the position of the tumor tissue (whether it is close or deep to the skin) or the shape.
[0007]
In order to solve the above-mentioned problems, Japanese Patent Laid-Open No. 9-497 has a plurality of spectral transmission characteristics of the imaging side filter on the imaging side so that the operator can select and use the optimum filter. An operation for selecting a filter is required for the surgeon, and since the plurality of filters are provided, the imaging means is enlarged and the operability is lowered.
[0008]
Further, the second aspect has the following problems.
In JP-A-3-97439 and JP-A-6-125911, ultraviolet light and normal light are automatically switched and irradiated, and in synchronization therewith, a filter on the imaging means side is also switched to produce a fluorescent image by ultraviolet light and an appearance image by normal light. It can be taken. Alternatively, the fluorescent image and the appearance image can be alternately picked up by two image pickup means.
[0009]
In this case, the timing of switching between the ultraviolet light and the normal light is fixed for a certain period of time, so if the emission intensity of the fluorescence is weak due to the short time of irradiation with the ultraviolet light, there is a risk of overlooking the fluorescent part. I cannot change the setting. In addition, when it is desired to view the appearance image by normal light without stagnation according to the preference of the operator, it is possible to set the normal light observation time longer, but the time setting cannot be made.
[0010]
Further, the third aspect has the following problems.
In JP-A-6-125911, a photodetector and a dedicated image guide for guiding fluorescence to the photodetector are provided in order to detect fluorescence. However, the diameter of the endoscope is increased, and the TV camera as an imaging means is provided. The size was increased and the operability was reduced. In addition to an external TV camera, it is necessary to prepare a dedicated endoscope, which increases the cost.
[0011]
(Object of invention)
The present invention has been made in view of the above points, and an object thereof is to provide a fluorescence observation endoscope apparatus capable of always obtaining a fluorescence observation image with an optimum contrast regardless of variations in spectral characteristics of filters. To do.
It is another object of the present invention to provide a fluorescence observation endoscope apparatus that can switch and set the illumination period of white light and excitation light according to the surgical procedure or the preference of the surgeon.
It is another object of the present invention to provide a fluorescence observation endoscope apparatus that notifies that fluorescence has been detected without increasing the diameter or size of an endoscope or an imaging apparatus.
[0012]
[Means for Solving the Problems]
In a fluorescence observation apparatus for displaying a fluorescence image obtained by irradiating excitation light to a test object containing a fluorescent substance, white light supply means for supplying predetermined white light to the test object, and the white light White light imaging means for picking up reflected light of white light supplied to the test object by a supply means, an excitation light supply light source for supplying the excitation light to the test object, and supplied to the test object Fluorescence excited by excitation light When, Wavelength band of which the excitation light supplied from the excitation light supply light source is band-limited by a predetermined band-limiting filter among the reflected light reflected by the test object Is the light of With background light The Fluorescence imaging means for receiving and imaging, normal observation mode in which the predetermined white light and the excitation light are alternately irradiated to the subject to be examined at a set time, and only the excitation light to the subject to be examined A fluorescence observation mode for irradiating, a normal observation mode and a fluorescence observation mode, Switching from one observation mode to the other Control mode switching Based on an imaging signal from the control means, the fluorescence imaging means, an intensity detection means for detecting the intensity of at least one of the background light or the fluorescence, and the intensity detection means Of the background light Strength First Determine whether it is within the specified setting range Or determining whether the fluorescence intensity is greater than a second predetermined range. Detected by determination means and the intensity detection means Of the background light Strength Said first predetermined If it is determined by the determination means that it is out of the setting range, the background light's Strength above First predetermined A strength correction means for correcting to be within the setting range; If the intensity of the fluorescence detected by the intensity detection means is greater than the second predetermined set range, the fluorescence greater than the second predetermined set range is detected when determined by the determination means. Fluorescent notification means for notifying Have , Said mode switching The control means uses the determination means The intensity of the fluorescence is Above Second predetermined When larger than the setting range , During the normal observation mode If determined, the normal observation mode is changed to the fluorescence observation mode. Mode switching By performing the control, the background light or fluorescence intensity is adjusted to be within a predetermined range.
[0013]
Also ,in front White light supply by the white light supply means and excitation light supply by the excitation light supply light source Said Illumination light switching means for switching every set time, and the illumination light switching means Said The white light irradiation time and the excitation light irradiation time that can be set on the test object, and the imaging signal from the white light imaging means in synchronization with the timing of switching the irradiation light by the time setting means And an imaging signal switching means for switching and outputting an imaging signal from the fluorescence imaging means, and an imaging signal output from the imaging signal switching means, A white observation image obtained by image processing of the imaging signal from the white light imaging means, and a fluorescence observation obtained by image processing of the imaging signal from the fluorescence imaging means image When Or the composition of The white observation image and the fluorescence observation image Display at the same time Where The time for the white light irradiation and the time for the excitation light irradiation in the normal observation mode by the time setting means and the illumination light switching means operating in conjunction therewith are provided. Can be set according to the case and the preference of the surgeon.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
1 to 6 relate to the first embodiment of the present invention, FIG. 1 shows the overall configuration of the fluorescence observation endoscope apparatus of the first embodiment, and FIG. 2 shows the configuration of the first filter. 3 shows the configuration of the second filter, FIG. 4 shows the configuration of the third filter, and FIG. 5 shows the background light input to the imaging means during the fluorescence observation in the first embodiment. FIG. 6 is a timing chart showing the operation of the fluorescence observation endoscope apparatus.
[0016]
As shown in FIG. 1, an endoscope apparatus for fluorescence observation 1A according to a first embodiment of the present invention includes an optical endoscope 2 that performs endoscopy on a subject to be examined, and the endoscope. An external television camera (hereinafter abbreviated as a TV camera) 3 mounted on the mirror 2 and incorporating an image pickup means, a light source device 4 for supplying illumination light to the endoscope 2, and the TV camera 3 are controlled. By doing so, a camera control unit (hereinafter abbreviated as CCU) 5 that generates a video signal from an image pickup signal by the image pickup means and a monitor 6 as a display means are connected so that the video signal from the CCU 5 is input. Composed.
[0017]
The endoscope 2 includes, for example, a flexible elongated insertion portion 7, an operation portion 8 provided at the rear end thereof, an eyepiece portion 9 provided at the rear end of the operation portion 8, and an operation portion 8. And a light guide connector 11 provided at the end of the light guide cable 10, which can be detachably connected to the light source device 4.
[0018]
A light guide 12 having a function of transmitting white light for normal observation and excitation light used for fluorescence observation is inserted into the insertion portion 7, the operation portion 8, and the light guide cable 10 in the endoscope 3. By connecting the light guide connector 11 to the light source device 4, white light or excitation light is supplied from the light source device 4.
[0019]
In the light source device 4, for example, an ultra-high pressure mercury lamp 13 is provided as a normal observation illumination light source and excitation light source, and the light from the lamp 13 is supported by a step motor 14 so as to be rotatable. 15, and further supplied to the light incident end face of the light guide 12 through the condenser lens 16.
[0020]
As shown in FIG. 2, the first rotary filter 15 is provided with two semicircular openings in a disk-shaped filter frame, and the two openings have transparent glass 17 (or may remain open), blue Filters 18 are respectively attached.
[0021]
When the transparent glass 17 is on the illumination optical axis, white light is supplied to the light guide 12 as normal observation illumination light. On the other hand, when the blue filter 18 is on the optical axis, Is supplied with excitation light for fluorescence observation.
[0022]
The light transmitted by the light guide 12 is irradiated to the subject 22 side through the illumination lens 21 attached to the illumination window of the distal end portion 19 of the insertion portion 7. The distal end portion 19 is provided with an observation window adjacent to the illumination window, and an objective lens 23 is attached to the observation window.
[0023]
The fluorescent light excited and radiated by the reflected light or the excitation light from the illuminated subject 22 is imaged at its imaging position by the objective lens 23. At the image formation position, the front end surface of the image guide 24 is arranged, and the image formed on the front end surface is transmitted to the rear end surface by the image guide 24. The image guide 24 is inserted from the vicinity of the distal end portion 19 of the insertion portion 7 to the vicinity of the eyepiece portion 9.
An eyepiece lens 25 is attached to the eyepiece unit 9 so as to face the rear end surface of the image guide 24, and in the case of an image in the visible region, it can be enlarged and observed with the naked eye.
[0024]
In the TV camera 3 that is detachably connected to the connection unit 9, an imaging lens 26 on the optical axis O of the eyepiece lens 25 of the eyepiece unit 9, and an image sensor that also serves as a white light imaging unit and a fluorescence imaging unit. For example, a charge coupled device (abbreviated as CCD) 27 is disposed, and an image transmitted to the rear end face of the image guide 24 is imaged on the CCD 27 by the eyepiece lens 25 and the imaging lens 26. .
A color separation filter such as a mosaic filter for optical color separation is disposed on the front surface of the CCD 27.
[0025]
Between the imaging lens 26 and the CCD 27, a second rotary filter 29 that is rotatably supported by a second step motor 28, and a third that is rotatably supported by a third step motor 30. A rotary filter 31 is provided, and light from the rear end face of the image guide 24 passes through the second rotary filter 29 and the third rotary filter 31 and forms an image on the CCD 27.
[0026]
As shown in FIG. 3, the second rotary filter 29 has a filter 32a (or a hole) that transmits normal observation light at two circular openings provided in a disk-shaped light shielding member and 400 nm or more, or 450 nm or more. A band limiting filter 32b that transmits light in the wavelength band is attached. The band limiting filter 32b transmits a longer wavelength side than the wavelength of a part of the band of the excitation light used for excitation.
[0027]
As shown in FIG. 4, the third rotary filter 31 includes a filter 33a (or a hole) that transmits normal observation light in two circular openings provided in a disk-shaped light shielding member and 550 nm or less. Or a band limiting filter 33b that transmits light in a wavelength band of 600 nm or less. This band limiting filter 33b is set to have a characteristic of passing the shorter wavelength side from the middle wavelength between the fluorescence wavelength band on the long wavelength side and the wavelength band of the excitation light on the short wavelength side.
[0028]
As shown in FIG. 1, the TV camera 3 is provided with a mode switch 34 for switching modes, and the second and third step motors 28 and 30 and the mode switch 34 are arranged in the CCU 5. It is electrically connected to the control circuit 35.
[0029]
In the CCU 5, in addition to the control circuit 35, an image pickup signal from the CCD 27 is input, an image switching circuit 36 for switching and outputting a white observation image and a fluorescence observation image in the image pickup signal, and an output from the image switching circuit 36. An intensity measuring circuit 37 that measures the intensity of light according to the signal, a color matrix control circuit 38 that changes a color matrix (in color separation by the image processing circuit 39) in accordance with an output signal of the intensity measuring circuit 37, and image switching An output signal of the circuit 36 is input, and an image processing circuit 39 for performing image processing for synthesizing the white observation image and the fluorescence observation image or dividing and displaying on the monitor 6 is provided.
[0030]
The image switching circuit 36 is electrically connected to the control circuit 35, the intensity measurement circuit 37, and the image processing circuit 39. The color matrix control circuit 38 is electrically connected to the intensity measurement circuit 37 and the image processing circuit 39. The image processing circuit 39 is electrically connected to the monitor 6.
[0031]
The control circuit 35 controls the operations of the first step motor 15 in the light source device 5, the second step motor 28 in the TV camera 3, and the third step motor 30 in accordance with the operation of the mode switch 34. To do.
[0032]
In this embodiment, as will be described below, when fluorescence observation is performed, a part of excitation light is imaged together with fluorescence as background light, and further, the third rotary filter 31 is rotated from the imaging state. Then, only the background light is imaged, and the intensity of the background light is detected.
[0033]
Then, by this intensity detection, the fluorescence image component and the (contour image component by excitation light) are color-separated by the image processing circuit 39 via the color matrix control circuit 38 so that the intensity of the background light falls within a predetermined range. At the time of adjustment, the color separation weighting is controlled so that an image easy to diagnose can be obtained.
[0034]
Next, the operation of this embodiment will be described.
The filter arrangement during normal operation (observation under illumination of white light) during surgery or during diagnosis in the fluorescence observation endoscope apparatus 1A of the present embodiment will be described.
A transparent glass 17 provided on the first rotary filter 15 is inserted on the optical axis of the illumination light connecting the lamp 13 and the light guide connector 11 in the light source device 4. Thereby, the white light for normal observation comes to be irradiated to the test subject 22 side through the light guide 12.
[0035]
At this time, a filter 32 a disposed in the second rotary filter 29 and a filter 33 a disposed in the third rotary filter 31 are disposed on the optical axis O in the TV camera 3.
[0036]
The white light reflected from the subject 22 passes through the filters 32 a and 33 a and is imaged on the CCD 27. The imaging signal from the CCD 27 is input to the image switching circuit 36, and the image switching circuit 36 outputs the imaging signal to the image processing circuit 39 in normal observation.
[0037]
On the other hand, the image switching circuit 36 outputs to the image processing circuit 39 via the intensity measurement circuit 37 and the color matrix control circuit 38 in the case of fluorescence observation described later. The image processing circuit 39 synthesizes an image at the time of white observation and an image at the time of fluorescence observation or performs image processing such as divided display and displays the image on the monitor 6.
[0038]
Next, the filter arrangement at the time of fluorescence observation in the present embodiment will be described.
A blue filter 18 provided in the first rotary filter 15 is inserted on the optical axis of the illumination light connecting the lamp 13 and the light guide connector 11 in the light source device 4. Thereby, excitation light for fluorescence observation is irradiated to the subject 22 side through the light guide 12.
[0039]
At this time, on the optical axis O in the TV camera 3, a filter 32b disposed on the second rotary filter 29 and a filter 33a disposed on the third rotary filter 31 are disposed.
[0040]
The reflected light from the subject 22 passes through the filters 32b and 33a and forms an image on the CCD 27. At this time, reflected light and fluorescence of the excitation light incident on the CCD 27 are as shown in FIG.
[0041]
The excitation light that has passed through the blue filter 18 is cut off at a wavelength of 400 nm or less by the filter 32b, passes through the filter 33a, and is incident on the CCD 27 (the symbol H indicated by the hatched line in FIG. 5).
[0042]
Fluorescence excited by the excitation light and emitted (portion I indicated by cross-hatching in FIG. 5) passes through the filters 32b and 33a and enters the CCD 27. In the fluorescence observation, a part of the excitation light (part H) is used as background light, and the fluorescence (part I in FIG. 5) emitted from the photosensitive substance accumulated in the tumor by the excitation light is observed.
[0043]
At this time, the background light and fluorescence incident on the CCD 27 due to variations in transmission characteristics of the blue filter 18 and the filter 32b are as shown in FIG. 5A or 5D (for example, the filter characteristics of the blue filter 18, the band limiting filter). The level may vary (for example, due to the filter characteristics of 32b).
[0044]
In the case of FIG. 5A, the background light is too strong and the fluorescence is buried, and skill is required to identify the shape of the tumor. In the case of FIG. 5D, the background light is too weak to make it difficult to see the contour of the normal tissue part and the like, and the positional relationship between the normal tissue and the tumor part is difficult to understand.
[0045]
Therefore, in the present embodiment, the following correction process is performed.
The third rotary filter 31 rotates, and the filter 33b is disposed on the optical axis O for a fixed time (for example, about 1/60 second). Since the fluorescence is cut by the filter 33b, the excitation light and fluorescence incident on the CCD 27 are as shown in FIG. 5 (B) or (E).
[0046]
That is, only background light is incident on the CCD 27. The image pickup signal of the CCD 27 is input to the intensity measurement circuit 37 via the image switching circuit 36, and the intensity of the background light at this time is measured, and the intensity is stronger (larger) than the predetermined intensity K1 or weaker (smaller) than K2. ) Is determined by the intensity measurement circuit 37, and if it exceeds K1 or less than K2, the color matrix control circuit 38 corrects the intensity of the color component on the background light side during color separation by the image processing circuit 39. Then, the level is adjusted to the K3 level as shown in FIG. That is, in the case of FIG. 5C, the blue color component is suppressed to be small, and in the case of FIG. 5E, the blue color component is controlled to be large.
[0047]
After a certain time, the third filter 31 rotates, the filter 33a is arranged on the optical axis O, and the intensity of the background light is adjusted as shown in FIG. Fluorescence observation is possible.
[0048]
Next, the normal observation mode and the fluorescence observation mode in the apparatus 1A and switching thereof will be described.
Switching between the normal observation mode and the fluorescence observation mode is performed by pressing a mode changeover switch 34 provided in the TV camera 3. When the white observation mode is selected, the control circuit 35 in the CCU 5 controls the first step motor 15 in the light source device 4 to alternately emit white light and excitation light according to a predetermined time. The operation will be described with reference to the timing chart of FIG.
[0049]
In the white light observation (normal observation) mode, white light and excitation light are alternately irradiated according to a predetermined time. At this time, the control circuit 35 outputs drive signals to the first and second step motors 14 and 28 so that the irradiation time of the white light is set at the interval T1 and the irradiation time of the excitation light is set to T2.
[0050]
Similarly, the third step motor 30 is driven at the same timing as when the white light is switched to the excitation light, and the time from insertion of the filter 33b onto the optical axis O to insertion and withdrawal of the filter 33b is set to T3. A drive signal is applied so that the filter 33b is retracted.
[0051]
Times T1 and T2 can be set by the user. When the fluorescence intensity is weak, the CCD 27 is usually observed with an exposure time of about 1/60 seconds set to 1/30 to 1/10 seconds, but the time T2 is set to 1/30 to 1/10 according to the exposure time. Can be set to seconds or longer.
[0052]
In addition, in order to observe fluorescence emitted from the tumor in time series, white light and excitation light are switched at regular intervals, but depending on the case, fluorescence observation is not necessary or conversely Since it is necessary to switch to small increments and observe, the time T1 can be set according to the request.
[0053]
When the mode switch 34 is pressed, the fluorescence observation mode is selected, and a step signal is input to the control circuit 35 at time t1 in FIG. In response to this, the control circuit 35 outputs drive signals to the first and second step motors 14 and 28 at the same timing, and arranges the blue filter 18 and the filter 32a on the optical axis.
[0054]
At this time, only excitation light is emitted from the light source device 4. Driving to the third step motor 30 is also performed, and the background light is adjusted. When the mode switch 34 is pressed again, a step signal is input at time t2 in FIG. 6 and the normal observation mode is set.
[0055]
Then, a drive signal is input to the first and second step motors 14 and 28 via the control circuit 35, the transparent glass 17 and the filter 32b are arranged on the optical axis, and white light and excitation light are alternated again. Irradiate.
[0056]
The present embodiment has the following effects.
Regardless of variations in the optical characteristics of the blue filter 18 and the filter 32b, stable background light can be obtained, so that sufficient contrast between the tumor tissue and the normal tissue can be obtained, and the tumor tissue can be easily identified. Can be set and diagnosis is easy. In addition, since the optical characteristics of the blue filter 18 and the filter 32b can be allowed to vary greatly, the filter can be used at low cost and the cost can be reduced.
[0057]
Even with a high-pressure mercury lamp 13 having a strong intensity in the wavelength range used as background light and conventionally difficult to adjust the intensity of the background light, it is possible to obtain background light with an appropriate intensity.
[0058]
In general, since the fluorescence emitted by the excitation light is weak, the observation is performed by increasing the shutter speed of the CCD 27 as the imaging means. The time T2 during which the excitation light is irradiated during normal observation according to the shutter speed. Therefore, the fluorescence observation image can be reliably captured.
The time for switching between white light and excitation light can be set according to the operator's preference and case.
In addition, the endoscope 2 can obtain the same effect even if it is a rigid endoscope in which the image guide 24 is replaced with a relay lens.
[0059]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. Note that, in the second embodiment described below, the same reference numerals are given to the portions that perform the same functions as those in the first embodiment, and duplicate descriptions are omitted.
[0060]
FIG. 7 shows an overall schematic configuration of the fluorescence observation endoscope apparatus 1B of the present embodiment. This fluorescence observation endoscope apparatus 1B is the same as the fluorescence observation endoscope apparatus 1A shown in FIG. 1, but the CCU 5 is further provided with a notification circuit 40. The notification circuit 40 includes an intensity measurement circuit 37 and an image processing circuit 39. Electrically connected.
[0061]
In the present embodiment, as shown in FIG. 8, the third rotary filter 31 has a wavelength of 500 nm or more, or 550 nm (instead of the band limiting filter 33b that transmits a wavelength band of 600 nm or less in the first embodiment). A band limiting filter 33b 'that transmits the above wavelengths is provided.
Other configurations are the same as those of the first embodiment.
[0062]
Next, the operation of this embodiment will be described.
The fluorescence observation in the endoscope apparatus for fluorescence observation 1B of the present embodiment will be described. In the fluorescence observation mode, a blue filter 18 provided in the first rotary filter 15 is inserted on the optical axis connecting the lamp 13 and the light guide connector 11 in the light source device 4.
[0063]
As a result, the subject 22 is irradiated with excitation light for fluorescence observation via the light guide 12. At this time, on the optical axis O in the TV camera 3, a filter 32b disposed on the second rotary filter 29 and a filter 33a disposed on the third rotary filter 31 are disposed.
[0064]
Then, the reflected light of the excitation light from the subject 22 is imaged on the CCD 27 through the filters 32b and 33a. At this time, the reflected light and the fluorescence of the excitation light incident on the CCD 27 are a mixture of the background light indicated by symbol H and the fluorescence indicated by symbol I as shown in FIG. 9A or 9D. .
[0065]
That is, the excitation light transmitted through the blue filter 18 is cut off at a wavelength of 400 nm or less by the filter 32b, passes through the filter 33a, and enters the CCD 27 (part H).
[0066]
After the mode is switched, the third step motor 30 rotates, and the filter 33b 'is inserted on the optical path for a certain time. Since the background light (part H) is cut by the filter 33b ', the light incident on the CCD 27 is as shown in FIG. 9B or FIG.
[0067]
That is, only the fluorescence is incident on the CCD 27. The imaging signal of the CCD 27 at this time is input to the intensity measuring circuit 37 via the image switching circuit 36, and the intensity of the fluorescence is measured by the intensity measuring circuit 37, and the fluorescence stronger than the predetermined intensity K6 as shown in FIG. Is imaged, the notification circuit 40 is turned on, and “Tumor” or the like is displayed on the monitor 6 via the image processing circuit 39, or a warning sound or a sound such as “There is a tumor” is notified. Urge the surgeon to press the mode switch 34.
[0068]
Further, when the intensity measurement circuit 37 determines that the intensity of the fluorescence is weak but greater than the intensity K4, the color matrix control circuit 38 emphasizes the fluorescence to an intensity of about K5 (see FIG. 9C).
[0069]
After a certain time, the third rotary filter 31 rotates, the filter 33a is arranged on the optical axis O, and the incident excitation light and fluorescence become as shown in FIG. 9F, and even weak fluorescence is observed. It becomes possible.
[0070]
The present embodiment has the following effects.
By providing the CCD 27, which is an imaging means, with a light detection function, it is possible to detect fluorescence without increasing the size of the TV camera 3, and to inform the surgeon that fluorescence is being observed.
[0071]
Further, weak fluorescence can be detected and highlighted.
[0072]
(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. Note that, in the third embodiment described below, the same reference numerals are given to portions that perform the same functions as those in the first and second embodiments, and duplicate descriptions are omitted.
[0073]
FIG. 10 shows a schematic configuration of the entire fluorescence observation endoscope apparatus 1C according to the third embodiment.
[0074]
The fluorescence observation endoscope apparatus 1C is further provided with a display switching circuit 41 in the CCU 5 in the fluorescence observation endoscope apparatus 1A shown in FIG. 1. The display switching circuit 41 includes a control circuit 35, an intensity measurement circuit 37, The image processing circuit 39 is electrically connected.
[0075]
Further, instead of the third rotary filter 31 in the TV camera 3 of FIG. 1, a third rotary filter 31 ′ having three filters as shown in FIG. 11 is adopted.
[0076]
As shown in FIG. 11, the third rotary filter 31 ′ is provided with a filter 33a (or a hole) that transmits normal observation light by providing three openings in the circumferential direction of the disc-shaped light-shielding member. A band limiting filter 33b that transmits a wavelength band of 550 nm or less or 600 nm or less and a band limiting filter 33b ′ that transmits a wavelength of 500 nm or more or 550 nm or more are provided. Other configurations are the same as those of the first embodiment.
[0077]
Next, the operation of this embodiment will be described.
The fluorescence observation in the endoscope apparatus for fluorescence observation 1C of the third embodiment will be described. In the fluorescence observation mode, first, the filter 33b of the third rotary filter 31 ′ in the TV camera 3 is arranged on the optical axis O. The reflected white light from the subject 22 passes through the filters 32b and 33a and forms an image on the CCD 27.
[0078]
At this time, reflected light and fluorescence of the excitation light incident on the CCD 27 are as shown in FIG. 5A or FIG. 5D in the first embodiment, but after the mode is switched, the third rotary filter 31 is switched. 'Rotates, and the filter 33b is inserted into the optical path for a certain period of time.
[0079]
At this time, the light incident on the CCD 27 is as shown in FIG. 5B or FIG. 5D of the first embodiment, and the intensity of the background light is appropriately adjusted by the same action as the first embodiment. adjust. Next, the third rotary filter 31 'rotates, and the filter 33b' is inserted on the optical path for a fixed time. At this time, the light incident on the CCD 27 is as shown in FIG. 9B or FIG. 9E of the second embodiment. In the case of FIG. 9B, the intensity of the fluorescence is adjusted to an appropriate intensity by the same action as in the second embodiment.
[0080]
Further, as shown in FIG. 9E, the intensity of the fluorescence incident on the CCD 27 is measured by the intensity measurement circuit 37, and when fluorescence greater than the predetermined intensity K6 is imaged, the display switching circuit 41 is used. Signals are output to the control circuit 35 and the image processing circuit 39 to automatically switch to the fluorescence observation mode, and display on the monitor 6 also displays a fluorescence observation image.
[0081]
Next, switching between the normal observation mode and the fluorescence observation mode in the present embodiment will be described. When the display switching circuit 41 is activated, switching from the normal observation mode to the fluorescence observation mode is performed. The operation will be described with reference to the timing chart of FIG.
[0082]
In the white light observation (normal observation) mode, similarly to the first embodiment, the drive signal is output so that the white light irradiation time is T1 and the excitation light irradiation time is T2.
[0083]
The third step motor 30 is driven at the same timing as when the white light is switched to the excitation light. After the filter 33b is inserted onto the optical axis O, the filter 33b 'is then inserted into the optical axis O. The drive signal is applied and the filters 33b and 33b 'are inserted on the optical axis O in order so that the time until insertion is T4 and the time from insertion of the filter 33b' to retraction is T5. To do.
[0084]
When the display switching circuit 41 operates, a step signal from the display switching circuit 41 is input to the control circuit 35 as shown in FIG. In response to this, the control circuit 35 outputs the drive signals shown in FIG. 12 to the first and second step motors 14 and 28, and arranges the blue filter 18 and the filter 32a on the optical axis.
[0085]
At this time, only excitation light is emitted from the light source device 4. Further, the third step motor 30 is also synchronized with the first and second step motors 14 and 28, and the filter 33b is inserted onto the optical axis, and after the insertion, the filter 33b is retracted after the time T4, After the insertion of the filter 33b 'on the optical axis and after the insertion, the filter 33b' is retracted after time T5, the filter 33a is disposed on the optical axis, and the operation state in the fluorescence observation mode is set.
[0086]
That is, when the normal observation mode is set by the mode changeover switch 34 in FIG. 12, the fluorescence observation is automatically performed even if the mode changeover switch 34 is not operated by the output signal of the display changeover circuit 41 (shown by a dotted line in FIG. 12). Switch to mode.
[0087]
Therefore, in this state (that is, the state in which the mode is automatically switched to the fluorescence observation mode), when the next operation of pressing the mode switch 34 is performed, the normal observation mode is set, and the first and second modes are set via the control circuit 35. The drive signals are input to the step motors 14 and 28, the transparent glass 17 and the filter 32b are disposed on the optical path, and the white light and the excitation light are alternately irradiated.
[0088]
The present embodiment has the following effects.
Compared with the first and second embodiments, background light and fluorescence can be adjusted more appropriately.
When fluorescence exceeding a predetermined level is detected, the mode is automatically switched to the fluorescence observation mode, so that the surgeon can save time and effort for switching the mode.
[0089]
[Appendix]
1. In a fluorescence observation apparatus that displays a fluorescence image obtained by irradiating excitation light to a test object containing a fluorescent substance,
An excitation light supply light source for supplying the excitation light;
Fluorescence imaging means for receiving and imaging fluorescence excited by excitation light supplied to the subject to be examined and a part of a region of excitation light supplied from the excitation light supply light source as background light;
Peak value detection means for detecting a peak value of at least one of the background light or the fluorescence based on an imaging signal from the fluorescence imaging means;
Determining means for determining whether or not the peak value of the intensity obtained by the peak value means is a predetermined set value;
Peak value correction for correcting the peak value and intensity of at least one of the background light and the fluorescence so that the peak value becomes a set value when the determination unit determines that the peak value is outside the set value Means,
An endoscope apparatus for fluorescence observation having
[0090]
(Effect of Supplementary Note 1) Since the peak value of the intensity of the background light or fluorescence can be measured and the peak value can be corrected to an appropriate value, the characteristics of the filters disposed in the light source and the imaging device vary. In addition, the optimum contrast between the background light and the fluorescence can always be obtained, and the visibility of the fluorescence emitted by the tumor is improved.
[0091]
2. White light supply means for supplying predetermined white light to the test object;
White light imaging means for imaging reflected light of white light supplied to the subject by the white light supply means;
Illumination light switching means for switching white light supply by the white light supply means and excitation light supply by the excitation light supply light source at set time intervals;
The white light irradiation time irradiated to the test object by the illumination light switching means, and the time setting means capable of setting the ultraviolet light irradiation time,
In synchronization with the switching timing of the irradiation light by the time setting means, an imaging signal switching means for switching and outputting the imaging signal from the white light imaging means and the imaging signal from the fluorescence imaging means,
Image processing means for performing processing such as image synthesis or simultaneous display based on the imaging signal output from the imaging signal switching means;
The endoscope apparatus for fluorescence observation according to appendix 1, characterized by comprising:
[0092]
(Effect of Supplementary Note 2) Since the irradiation time of the white light and the excitation light in the normal observation mode can be set, it is possible to reliably image even weak fluorescence by setting the irradiation time of the excitation light long. Further, by setting the irradiation time of the normal light longer, it is possible to observe the appearance image with white light without stagnation, and it is possible to observe as intended by the operator.
[0093]
3. Fluorescence detection means for detecting fluorescence based on an imaging signal from the fluorescence imaging means, and fluorescence notification means for notifying that the fluorescence has been detected when fluorescence is detected by the fluorescence detection means. The endoscope apparatus for fluorescence observation according to supplementary note 1 or 2, characterized in that.
(Effect of Supplementary Note 3) Fluorescence can be detected without increasing the diameter and size of the endoscope and the imaging device, and the operator can be notified.
[0094]
4). The peak value detecting means is disposed so as to be detachable from the imaging means on the subject side, and includes a filter means for blocking either the background light or the fluorescence, a light intensity measuring means, The endoscope apparatus for fluorescence observations according to Supplementary notes 1 to 3, comprising:
5). The endoscope apparatus for fluorescence observation according to appendices 1 to 4, wherein the fluorescence imaging unit and the white light imaging gown are common imaging units.
6). The endoscope for fluorescence observation according to appendices 3, 4, and 5, wherein the fluorescence detection means is the peak value detection means.
7). The endoscope apparatus for fluorescence observation according to appendices 1 to 6, wherein the peak value correcting means is a color matrix changing means.
[0095]
【The invention's effect】
As described above, according to the present invention, according to the first aspect, the background light and the fluorescence can always be set to an appropriate contrast state, and a fluorescent image that is easy to diagnose can be provided.
According to claim 2, the illumination time of the white light and the excitation light can be freely set according to the surgical method or the preference of the operator.
According to claim 3, it is possible to notify that fluorescence has been detected without increasing the diameter or size of the endoscope or the imaging device.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a fluorescence observation endoscope apparatus according to a first embodiment of the present invention.
FIG. 2 is a front view showing a configuration of a first filter.
FIG. 3 is a front view showing a configuration of a second filter.
FIG. 4 is a front view showing a configuration of a third filter.
FIG. 5 is a characteristic diagram showing characteristics of background light and fluorescence input to the imaging means during fluorescence observation in the first embodiment.
FIG. 6 is a timing chart showing the operation of the fluorescence observation endoscope apparatus.
FIG. 7 is a diagram showing an overall configuration of a fluorescence observation endoscope apparatus according to a second embodiment of the present invention.
FIG. 8 is a front view showing a configuration of a third filter.
FIG. 9 is a characteristic diagram showing characteristics of background light and fluorescence input to the imaging means during fluorescence observation.
FIG. 10 is a diagram showing an overall configuration of a fluorescence observation endoscope apparatus according to a third embodiment of the present invention.
FIG. 11 is a front view showing a configuration of a third filter.
FIG. 12 is a timing chart showing the operation of the fluorescence observation endoscope apparatus.
[Explanation of symbols]
1 ... Endoscope device for fluorescence observation
2. Endoscope
3 ... TV camera
5 ... Camera Control Unit (CCU)
4. Light source device
6 ... Monitor
7 ... Insertion part
8 ... Operation part
9 ... Eyepiece
10. Light guide cable
11 ... Light guide connector
12. Light guide
13 ... Super high pressure mercury lamp
14: First step motor
15 ... 1st rotation filter
16 ... Condensing lens
17 ... Transparent glass
18 ... Blue filter
19 ... tip
21 ... Lighting lens
23 ... Objective lens
24. Image guide
25 ... Eyepiece
27 ... CCD
28 ... Second step motor
29 ... Second rotary filter
30 ... Third step motor
31 ... Third rotary filter
32 ... Filter (or hole)
32b ... Band-limiting filter
33a ... Filter (or hole)
33b ... Band-limiting filter
34. Mode selector switch
35 ... Control circuit
36. Image switching circuit
37. Strength measurement circuit
38 ... Color matrix control circuit
39. Image processing circuit

Claims (2)

In a fluorescence observation apparatus that displays a fluorescence image obtained by irradiating excitation light to a test object containing a fluorescent substance,
White light supply means for supplying predetermined white light to the test object;
White light imaging means for imaging reflected light of white light supplied to the subject by the white light supply means;
An excitation light supply light source for supplying the excitation light to the subject to be examined;
Band limitation by the the fluorescence excited by the excitation light to be supplied to a subject, of the excitation light supplied from the supply source is reflected light reflected excitation light by the test subject, a predetermined band limiting filter Fluorescence imaging means for receiving and imaging background light, which is light in the wavelength band,
A normal observation mode in which the test object is alternately irradiated with the predetermined white light and the excitation light every set time; and
A fluorescence observation mode in which only the excitation light is irradiated to the test object;
Mode switching control means for performing mode switching control from one observation mode to the other observation mode of the normal observation mode and the fluorescence observation mode;
Intensity detection means for detecting the intensity of at least one of the background light or the fluorescence based on an imaging signal from the fluorescence imaging means;
It is determined whether the intensity of the background light obtained by the intensity detection means is within a first predetermined setting range, or whether the intensity of the fluorescence is greater than a second predetermined range. Determination means to perform ,
When the determination means determines that the intensity of the background light detected by the intensity detection means is outside the first predetermined setting range, the intensity of the background light is set to the first predetermined intensity. Strength correction means for correcting to be within the set range of
If the intensity of the fluorescence detected by the intensity detection means is greater than the second predetermined set range, the fluorescence greater than the second predetermined set range is detected when determined by the determination means. Fluorescent notification means for notifying
Have,
The mode switching control unit switches from the normal observation mode to the fluorescence observation mode when the determination unit determines that the intensity of the fluorescence is larger than the second predetermined setting range during the normal observation mode. An endoscope apparatus for fluorescence observation characterized by performing mode switching control. Illumination light switching means for switching white light supply by the white light supply means and excitation light supply by the excitation light supply light source at each set time;
A white light irradiation time irradiated on the subject by the illumination light switching means, and a time setting means capable of setting an excitation light irradiation time;
In synchronization with the switching timing of the irradiation light by the time setting means, an imaging signal switching means for switching and outputting the imaging signal from the white light imaging means and the imaging signal from the fluorescence imaging means,
Based on the imaging signal output from the imaging signal switching unit, the white observation image obtained by image processing the imaging signal from the white light imaging unit and the imaging signal from the fluorescence imaging unit are obtained by image processing. The endoscope apparatus for fluorescence observation according to claim 1, further comprising image processing means for performing a process of combining the fluorescence observation image or displaying the white observation image and the fluorescence observation image at the same time.

Images