JP4587811B2 - Fluorescence observation endoscope device - Google Patents

Description

The present invention relates to a fluorescence observation endoscope apparatus for observing and diagnosing a lesion such as a cancer from fluorescence from a tissue by irradiating light transendoscopically, and in particular, detects a plurality of specific wavelengths of fluorescence to form an image. The present invention relates to a fluorescence observation endoscope apparatus.

    In recent years, autofluorescence from a living body and fluorescence of a drug injected into a living body are detected as a two-dimensional image, and a disease state (for example, disease type or infiltration range) such as degeneration of a living tissue or cancer is diagnosed from the fluorescence image. Techniques are shown in US Pat. No. 4,556,057 and US Pat. No. 5,042,494.

  When light is irradiated onto a living tissue, fluorescence having a wavelength longer than that of the excitation light is generated. Examples of fluorescent substances in vivo include NADH (nicotinamide adenine nucleotide), FMN (flavin mononucleotide), pyridine nucleotide, and the like. Recently, the correlation between these endogenous substances and diseases is becoming clearer. .

  In addition, fluorescent agents such as HpD (hematoporphyrin), Photofrin, ALA (δ-amino levulinic acid) have the ability to accumulate in cancer. By injecting these fluorescent agents into a living body and performing fluorescence observation, disease The site can be diagnosed.

As a technique for diagnosing a lesion part from the above fluorescence transendoscopically, for example, there is a fluorescence observation endoscope apparatus such as JP-A-8-224208.
US Pat. No. 4,556,057 US Pat. No. 5,042,494 JP-A-8-224208

  However, in the examination with the conventional fluorescence observation endoscope apparatus, when the lesion is small, the fluorescence intensity is small. Therefore, depending on the speed of the endoscope operation in the examination and the skill level of the operator, the fluorescence may be reduced. In spite of the occurrence, there is a problem that a lesion or the like may be overlooked.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a fluorescence observation endoscope apparatus that can reliably notify the presence of a lesion even when the lesion or the like is small and the fluorescence intensity is small. It is said.

The fluorescence observation endoscope apparatus of the present invention is
An endoscope for capturing a fluorescent image from a living tissue in a body cavity;
A fluorescence image generation means for performing signal processing on the imaging signal of the fluorescence image to generate a fluorescence image,
The fluorescent image generating means includes
Fluorescent pixel extraction means for extracting fluorescent pixels from the fluorescent image ;
Fluorescent pixel extraction stopping means for stopping the extraction of the fluorescent pixels by the fluorescent pixel extracting means when the sum of the luminances of all the pixels of the fluorescent image is a predetermined value or less;
A suspect target detecting means for detecting a suspect target by calculating a fluorescence level of a predetermined region centered on the fluorescent pixel extracted by the fluorescent pixel extracting means, and comparing with a predetermined level ;
Suspect target notifying means for notifying the existence of the suspect target detected by the suspect target detecting means ;
It is comprised.

  According to the present invention, even when a lesion or the like is small and the fluorescence intensity is small, there is an effect that the presence of a lesion can be reliably notified.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIGS. 1 to 11 relate to Embodiment 1 of the present invention, FIG. 1 is a block diagram showing the overall configuration of a fluorescence observation endoscope apparatus for diagnosing a lesion by fluorescence, and FIG. 2 is an interference diagram of the optical filter of FIG. 3 is a characteristic diagram showing the transmission characteristics of the color filter of the optical filter of FIG. 1, FIG. 4 is a characteristic chart showing the transmission characteristics of the optical filter of FIG. 1 and the spectral characteristics of the color image sensor. 5 is a functional block diagram for explaining the function of the image processor of FIG. 1, FIG. 6 is a flowchart for explaining the operation of the image processor of FIG. 5, and FIG. 7 is a diagram for explaining the action of the target occurrence notification function of FIG. 8 is a diagram for explaining a first modification of the operation of the target occurrence notification function of FIG. 5, FIG. 9 is a diagram for explaining a second modification of the operation of the target occurrence notification function of FIG. 5, and FIG. The third modification of the action of the target occurrence notification function 5 Description figures, FIG. 11 is a view for explaining a fourth modification of the action of the target generated notifying function of FIG.

  As shown in FIG. 1, a fluorescence observation endoscope apparatus 1 of the present embodiment includes a light source 2 that generates light (excitation light) in a blue or ultraviolet region, and guides the excitation light to a living body cavity from a lesioned part 3. An endoscope 4 for observing the generated fluorescence, a camera control unit 6 for driving a color imaging device 5 built in the endoscope 4 to convert a fluorescent image of the lesioned part 3 into a video signal, and the video signal And an image processor 7 that makes it easy to recognize the lesioned part 3 and the normal part, and a monitor 8 that displays the output of the image processor 7 as an image.

  The light source 2 incorporates a laser 9 such as an excimer that emits light in the blue or ultraviolet region, He—Cd, or argon. The endoscope 4 includes a light guide 10 that guides laser light emitted from the laser 9 to a living body lumen, a concave lens 11 that diffuses and illuminates the laser light, and a fluorescence image of a lesioned part 3 on a color imaging device 5. The objective lens 12 to project and the optical filter 13 which permeate | transmits a specific wavelength among the fluorescence images from the objective lens 12 are comprised.

  The endoscope 4 of the fluorescence observation endoscope apparatus 1 includes a light guide 10 that guides laser light emitted from a laser 9 to a living body lumen, a concave lens 11 that diffuses and illuminates the laser light, and a fluorescent image of a lesioned part 3. Is provided with an objective lens 12 that projects the image onto the color image sensor 5 and an optical filter 13 that transmits a specific wavelength of the fluorescent image. The optical filter 13 has a transmission characteristic that transmits green of 500 nm to 540 nm and red of 640 nm to 700 nm.

  The optical filter 13 includes an interference filter having a transmission characteristic as shown in FIG. 2 and a color filter having a transmission characteristic as shown in FIG. 3. As a result, the optical filter 13 has a transmission characteristic as shown by a solid line in FIG. have.

  Although not shown, the light source 2 includes a xenon lamp that generates white light and a switching unit that switches the light of the laser 9 and the xenon lamp and supplies the light to the light guide 10. The endoscope 4 includes an image pickup device (not shown) that picks up an image of white light.

  As shown in FIG. 5, the image processor 7 serving as a fluorescent image generating unit has a fluorescent pixel extraction function 50, a fluorescent total signal calculation function 51, an abnormality determination function 52, and a target occurrence notification function 53. Details of these functions will be described later.

  In the image processor 7 of the present embodiment configured as described above, as shown in FIG. 6, the fluorescent pixel extraction function 50 scans the fluorescent image of one frame imaged by the color image sensor 5 in step S1 and displays it on the fluorescent image. Extract fluorescent pixels.

  Here, the fluorescent pixel means a pixel having a luminance exceeding a predetermined level, for example, 20%, of the background level of the fluorescent image of one frame.

  If there is a fluorescent pixel, the fluorescent total signal calculation function 51 calculates the total signal intensity by summing the signal intensities of all pixels in a predetermined size area centered on the corresponding fluorescent pixel in step S2.

  Next, whether or not the abnormality determination function 52 as the suspect target extraction means is fluorescence from an abnormal tissue (suspect target) such as cancer by checking whether or not the total signal intensity exceeds a predetermined set level in step S3. judge.

  When the total signal intensity exceeds a predetermined set level and is determined to be fluorescence from an abnormal tissue (suspect target) such as cancer, the target occurrence notification function 53 sets a target presentation mark (described later) on the monitor 8 for a predetermined time in step S4. After the display, the next frame is moved to and proceeds to step S6.

  If the total signal intensity is below a predetermined set level, it is determined that the fluorescence is not from abnormal tissue (suspect target) such as cancer, and in step S5, whether or not there is another fluorescent pixel in the same frame to scan. If there is another fluorescent pixel, the process returns to step S2, and if not, the process moves to the next frame and then proceeds to step S6.

  In step S6, it is determined whether or not there is an instruction to end the examination by the fluorescence observation endoscope apparatus 1. If there is no instruction to end the examination, the process returns to step S1, and if there is an instruction to end the examination, the process ends.

  Here, the display process of the target presentation mark by the target occurrence notification function 53 as the suspected target notification means in step S4 will be described.

  As shown in FIG. 7, the target generation notification function 53 of the image processor 7 is displayed on the monitor 8 when it is determined that the total signal intensity exceeds a predetermined set level and the fluorescence is from an abnormal tissue (suspect target) such as cancer. The target presentation mark 101 is displayed at a position adjacent to the fluorescent image 100, and the presence of abnormal tissue (suspect target) such as cancer is notified. At this time, the brightness of the target presentation mark 101 reflects the size of an abnormal tissue (suspect target) such as cancer.

  As described above, in this embodiment, when the fluorescent region in a certain region on the fluorescent screen exceeds a predetermined setting level, the target presentation mark 101 is displayed on the monitor 8, so that the lesion or the like is small and the fluorescent intensity is small. However, oversight of the presence of the lesion can be reliably prevented.

  Note that by providing a speaker (not shown) in the image processor 7, the target occurrence notification function 53 may notify the presence of abnormal tissue (suspect target) such as cancer by using a speaker.

  Further, as shown in FIG. 8, the target occurrence notification function 53 is displayed on the monitor 8 when the total signal intensity exceeds a predetermined set level and it is determined that the fluorescence is from an abnormal tissue (suspect target) such as cancer. The target indicator 111 may be displayed at a position adjacent to the fluorescent image 100 to notify the presence of abnormal tissue (suspect target) such as cancer. With the target indicator 111, the intensity of the fluorescence is displayed with variable levels and colors, so that the notification reflecting the size of the lesion (suspected target) can be made.

  Further, as shown in FIG. 9, the target generation notification function 53 is provided with a direction navigation display unit 121 on the outer peripheral portion of the fluorescent image 100 in addition to the target presentation mark 101. In this case, the total signal strength is a predetermined set level. If it is determined that the fluorescence is from an abnormal tissue (suspect target) such as cancer, the direction navigation display unit 121 of the direction portion where the abnormal tissue (suspect target) such as cancer exists is turned on to notify.

  As shown in FIGS. 10 and 11, the target occurrence notification function 53 may display the position navigation display unit 150 in the vicinity of or adjacent to the suspect target in the fluorescent image 100.

  FIG. 10 shows an example in which the position navigation display unit 150 is displayed by a crosshair, and shows that the vicinity of the intersection of the crosshair is the suspected target position. Further, FIG. 11 is an example in which the position navigation display unit 150 is displayed by an arrow (which may be turned on or blinked), and indicates that the vicinity of the tip of the arrow is the suspected target position.

  In this embodiment, when the total luminance of all the pixels in the fluorescent image is below a predetermined level, the extraction of the fluorescent pixels can be stopped. In such a case, the noise component of each pixel is large, and it is considered that the reliability of the measurement is doubtful.

  The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the scope of the present invention.

1 is a configuration diagram showing the overall configuration of a fluorescence observation endoscope apparatus for diagnosing a lesion site by fluorescence according to Embodiment 1 of the present invention. 1 is a characteristic diagram showing the transmission characteristics of the interference filter of the optical filter of FIG. 1 is a characteristic diagram showing the transmission characteristics of the color filter of the optical filter of FIG. 1 is a characteristic diagram showing the transmission characteristics of the optical filter of FIG. 1 and the spectral characteristics of a color image sensor. Functional block diagram for explaining the functions of the image processor of FIG. Flowchart for explaining the operation of the image processor of FIG. The figure explaining the effect | action of the target generation notification function of FIG. The figure explaining the 1st modification of an effect | action of the target generation notification function of FIG. The figure explaining the 2nd modification of an effect | action of the target generation notification function of FIG. The figure explaining the 3rd modification of an effect | action of the target generation notification function of FIG. The figure explaining the 4th modification of an effect | action of the target generation notification function of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fluorescence observation endoscope apparatus 2 ... Light source 3 ... Lesion part 4 ... Endoscope 5 ... Color imaging device 6 ... Camera control unit 7 ... Image processor 8 ... Monitor 9 ... Laser 10 ... Light guide 11 ... Concave lens 12 ... Objective Lens 13 ... Optical filter 50 ... Fluorescence pixel extraction function 51 ... Fluorescence total signal calculation function 52 ... Abnormality determination function (suspect target extraction means)
53 ... Target occurrence notification function (Suspected target notification means)
100 ... Fluorescent image 101 ... Target presentation mark Agent Patent attorney Susumu Ito

Claims (7)

An endoscope for capturing a fluorescent image from a living tissue in a body cavity;
A fluorescence image generation means for performing signal processing on the imaging signal of the fluorescence image to generate a fluorescence image,
The fluorescent image generating means includes
Fluorescent pixel extraction means for extracting fluorescent pixels from the fluorescent image ;
Fluorescent pixel extraction stopping means for stopping the extraction of the fluorescent pixels by the fluorescent pixel extracting means when the sum of the luminances of all the pixels of the fluorescent image is a predetermined value or less;
A suspect target detecting means for detecting a suspect target by calculating a fluorescence level of a predetermined region centered on the fluorescent pixel extracted by the fluorescent pixel extracting means, and comparing with a predetermined level ;
Suspect target notifying means for notifying the existence of the suspect target detected by the suspect target detecting means ;
A fluorescence observation endoscope apparatus comprising: The fluorescence observation endoscope apparatus according to claim 1, wherein the suspect target notification means notifies by sound . The fluorescence observation endoscope apparatus according to claim 1, wherein the suspected target notifying unit notifies the fluorescent image by a graphic displayed in the vicinity of the suspected target . The fluorescence observation endoscope apparatus according to claim 3 , wherein the suspect target notifying unit varies the luminance of the figure in accordance with the suspect target . The fluorescence observation endoscope apparatus according to claim 3 , wherein the suspect target notifying unit varies the color of the graphic in accordance with the suspect target . The fluorescence observation endoscope apparatus according to claim 3 , wherein the suspect target notifying unit varies the shape of the figure according to the suspect target . The fluorescence observation endoscope apparatus according to claim 3 , wherein the suspect target notifying unit varies the display position of the graphic according to the suspect target .

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