JP2010179042A - Optical structure observation apparatus, structural information processing method therefor, and endoscope system with optical structure observation apparatus - Google Patents

Abstract

A three-dimensional structure of a duct structure is analyzed, and an internal state of a measurement target having the duct structure is easily diagnosed by a color image reflecting a desired color tone.
A processing unit 22 of an OCT processor includes an optical structure information detection unit 220, a glandular cavity extraction unit 221 as a glandular cavity extraction unit and a color tone switching unit, a threshold storage unit 222, and an extraction region setting unit as an extraction region setting unit. 223, a region information calculation unit 224 as a region information calculation unit, a parallel tomographic image generation unit 225 as a parallel tomographic image generation unit, a color map storage unit 226, a color tone editing unit 227 as a color tone editing unit, a display control unit 228 and I / F unit 229 is provided.
[Selection] Figure 5

Description

  The present invention relates to an optical structure observation apparatus, a structure information processing method thereof, and an endoscope system including the optical structure observation apparatus, and more particularly to an optical structure observation apparatus characterized by display processing in a pit pattern of a measurement target having a gland duct structure The present invention also relates to a structure information processing method and an endoscope system including an optical structure observation apparatus.

  Conventionally, when acquiring an optical tomographic image of a living tissue, an optical tomographic image acquisition apparatus using OCT (Optical Coherence Tomography) may be used. This optical tomographic image acquisition apparatus divides low-coherent light emitted from a light source into measurement light and reference light, and then reflects or backscatters light from the measurement object when the measurement light is applied to the measurement object. The light and the reference light are combined, and an optical tomographic image is acquired based on the intensity of the interference light between the reflected light and the reference light.

  The OCT measurement is roughly divided into two types: TD-OCT (Time domain OCT) measurement and FD-OCT (Fourier Domain OCT) measurement.

  In the TD-OCT measurement, the reflected light intensity distribution corresponding to the position in the depth direction of the measurement target (hereinafter referred to as the depth position) is acquired by measuring the interference light intensity while changing the optical path length of the reference light. Is the method.

  On the other hand, in the FD-OCT measurement, the interference light intensity is measured for each spectral component of the light without changing the optical path lengths of the reference light and the signal light, and the spectral interference intensity signal obtained here is Fourier transformed by a computer. This is a method of obtaining a reflected light intensity distribution corresponding to a depth position by performing a representative frequency analysis. In recent years, it has attracted attention as a technique that enables high-speed measurement by eliminating the need for mechanical scanning existing in TD-OCT.

  Typical examples of the apparatus configuration for performing FD-OCT measurement include an SD-OCT (Spectral Domain OCT) apparatus and an SS-OCT (Swept Source OCT).

  By the way, OCT measurement is a method for acquiring an optical tomographic image of a specific region as described above. Under an endoscope, for example, a cancer lesion is observed by observation with a normal illumination endoscope or a special optical endoscope. By finding and performing OCT measurement of the region, it is possible to determine how far the cancerous lesion has infiltrated. Further, by scanning the optical axis of the measurement light two-dimensionally, three-dimensional information can be acquired together with depth information obtained by OCT measurement.

  The fusion of OCT measurement and 3D computer graphic technology makes it possible to display a 3D structural model with a resolution on the order of micrometers. Alternatively, it is called optical three-dimensional structure information.

  OCT measurement has an advantage that the resolution is about 10 μm higher than that of ultrasonic measurement, and a detailed tomographic image inside the living body can be obtained. A three-dimensional tomographic image can be obtained by acquiring a plurality of images while shifting the position in a direction perpendicular to the tomographic image.

  For example, as shown in FIG. 26, the large intestine has a layer structure such as a mucosal layer, a mucosal muscular plate, a submucosal layer, and a proper muscular layer. As shown in FIG. A gland duct (crypt) is regularly arranged in the mucosal layer (Non-patent Document 1).

  For example, in endoscopic diagnosis of colorectal cancer, a gland duct (crypt) is observed under the endoscope, and classification based on the glandular cavity structure of the gland duct formed on the mucosal surface called a pit pattern is performed. However, the pit pattern diagnosis is a method for determining the degree of progress based on the image of the mucosal surface, and information on the depth of penetration is only empirical. Recently, there is an increasing number of cases where diagnosis is difficult due to the absence of abnormality in the pit pattern on the mucosal surface of a cancerous lesion.

  When the large intestine mucosa is measured three-dimensionally by the above-mentioned OCT measurement, the three-dimensional structure of the gland duct structure can be extracted, and the information in the vicinity of the surface can have the same structure as the pit pattern. Furthermore, since a three-dimensional structure is obtained by OCT measurement, changes in the depth direction of the gland duct structure are observed.

  For example, it is known that the gland duct structure of the mucosa layer collapses when the large intestine becomes cancerous (Non-patent Document 1). That is, a normal gland duct has a shape (normal state) like type I in FIG. 27, but due to canceration, the shape of the gland duct changes to a shape like type IV as shown in FIG. 28, for example. It is known that the gland duct itself will eventually collapse (lesion state).

  For example, a technique is disclosed that can numerically analyze the difference between normal and lesioned parts by reconstructing an OCT tomographic image three-dimensionally, extracting a gland duct from the OCT tomogram, and analyzing the shape (non-contrast) Patent Document 2). However, it is difficult to visually understand the extraction of the duct structure, and it is difficult to image the change in the three-dimensional lesion.

  On the other hand, full-color OCT measurement for viewing a tissue structure close to a natural color has been proposed (Patent Document 1). However, when observing in detail the glandular duct structure such as the large intestine, it is often difficult to understand even in full color. For example, in the pit pattern diagnosis using the endoscope described above, drugs such as dyes and stains are usually used. It is widely practiced to color and observe the features of the tissue structure clearly.

  In order to clearly observe the pit pattern on the mucosal surface, drugs called dyes and stains such as indigo carmine, methylene blue, crystal violet (pioctane) are used. For example, in the observation of the pit pattern of the large intestine, indigo carmine is used as a standard, and methylene blue or crystal violet is used when more detailed observation is required.

  However, indigo carmine used as a so-called dye method and methylene blue and crystal violet used as a staining method have the following differences in properties.

  Indigo carmine does not have the property of being absorbed by the living body, and a clear observation image can be obtained by accumulating in a concave portion according to the uneven shape of the mucosal surface. On the other hand, methylene blue and crystal violet are, for example, absorbed by the nucleus in the cell, thereby making it possible to clarify the contrast with the part that has not been absorbed.

  For example, the observation of the pit pattern of the large intestine with an endoscope observes the shape and arrangement of the glandular opening on the mucosal surface, but since the glandular opening is a fine hole opened on the mucosal surface, indigo carmine was sprayed. In some cases, the glandular opening is observed as a blue-green region in the endoscopic image. On the other hand, in the case of methylene blue and crystal violet, the gland orifice is naturally not stained because it is a blank space. As observed.

  In the observation with the above-mentioned pigments, there are problems such as inspection time and cost increase due to pigment spraying. To solve this problem, a method of reproducing the color contrast by image processing of the unevenness of the two-dimensional mucosal surface is proposed. (Patent Document 2).

Special table 2007-523386 gazette Japanese Patent Laid-Open No. 2001-25025

Diagnosis of large intestine PIT PATTERN, Author: Shinhide Kudo, Publisher: Medical School Journal of Biomedical Optics Vol. 13, p. 054055 (2008)

  However, the technique disclosed in Patent Document 2 emphasizes the unevenness of the mucosal surface by simple comparison of pixel signals, and does not reproduce the actual uneven shape of the mucosal surface. In addition, it corresponds only to the dye method using the indigo carmine that can obtain a clear contrast by using the unevenness of the mucosal surface, and the clear contrast can be obtained by using the absorption difference due to the tissue. There is a problem that the dyeing method using crystal violet cannot be supported.

  The present invention has been made in view of such circumstances, and a color image in which a three-dimensional structure of a gland duct structure is analyzed and a desired color tone is reflected on an internal state of a measurement target having the gland duct structure. It is an object of the present invention to provide an optical structure observation apparatus, a structure information processing method thereof, and an endoscope system including the optical structure observation apparatus that can be easily diagnosed by the above.

  In order to achieve the object, the optical structure observation apparatus according to claim 1 is orthogonal to the first direction which is a depth direction of a measurement target having a mucosal layer using low interference light and the first direction. A plurality of optical structure information of the measurement object obtained by scanning a scan plane consisting of the second direction is shifted while shifting the position along a third direction which is a direction substantially orthogonal to the scan plane; In the optical structure observation apparatus that constructs an optical three-dimensional structure image based on the plurality of acquired optical structure information, the mucosal layer is obtained by comparing information values of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold value. A glandular cavity extracting means for extracting the glandular cavity, an extraction area setting means for setting an extraction area having a plane parallel to the plane in the mucosa layer, and the optical structure in the extraction area set by the extraction area setting means Perform certain operations on information The color information of the parallel cross-sectional image based on the glandular cavity extracted by the glandular cavity extracting means, the parallel cross-sectional image generating means for generating a parallel cross-sectional image based on the calculation result of the area information calculating means, And color tone editing means for editing.

  The optical structure observation apparatus according to claim 1, wherein the glandular cavity extracting unit extracts the glandular cavity of the mucosal layer by comparing information values of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold value. The extraction area setting means sets an extraction area having a plane in the mucous membrane layer as a parallel cross section, and the optical information in the extraction area set by the extraction area setting means by the area information calculation means The parallel section image generation unit generates a parallel section image based on the calculation result of the region information calculation unit, and the color tone editing unit extracts the glandular cavity extraction unit. Based on the glandular cavity, by editing the color tone of the parallel sectional image, the three-dimensional structure of the gland duct structure was analyzed, and the internal state of the measurement target having the gland duct structure was reflected in the desired color tone Easy diagnosis with color images To enable Rukoto.

  The optical structure observation device according to claim 1, wherein the color tone editing unit adjusts the color tone of the parallel sectional image based on a preset color map. It is preferable to edit.

  The optical structure observation apparatus according to claim 2, wherein the color map specifies a color tone of at least one pigment of indigo carmine, crystal violet, and methylene blue. It is preferable.

  The optical structure observation device according to claim 2 or 3, further comprising a color tone switching unit that switches a color tone specified by the color map based on the predetermined threshold. It is preferable to provide.

  The optical structure observation device according to claim 4, wherein the color tone switching unit includes a plurality of sets according to a depth position of the plane in the mucosa layer. It is preferable to switch the color tone designated by the color map based on the predetermined threshold.

  The optical structure observation apparatus according to any one of claims 1 to 5, as in the optical structure observation apparatus according to claim 6, wherein the predetermined calculation executed by the region information calculation unit is It is preferable that the calculation is performed by any one of integration processing, maximum value projection processing, and minimum value projection processing that executes the optical structure information in the extraction region along a direction orthogonal to the plane.

  The optical structure observation device according to any one of claims 1 to 6, wherein the extraction region setting means includes a plurality of desired parallel to the plane. A plurality of extraction regions each having a plurality of parallel planes positioned at a height of a plurality of parallel planes, and the region information calculation unit executes the predetermined calculation for each of the plurality of extraction regions. Preferably, the parallel slice image generation means generates a plurality of the parallel slice images based on a calculation result for each of the plurality of extraction regions.

  The optical structure observation apparatus according to claim 7, further comprising an image composition unit that generates a composite image obtained by combining the plurality of parallel cross-sectional images. preferable.

  The optical structure observation device according to any one of claims 1 to 8, as in the optical structure observation device according to claim 9, wherein an arbitrary two-dimensional region is designated on the parallel sectional image. It is preferable to further include a dimension area specifying means and an image enlarging means for generating an enlarged image obtained by enlarging the image of the two-dimensional area.

  The optical structure observation device according to any one of claims 1 to 9, wherein the mucous membrane is obtained from the optical structure information constituting the optical three-dimensional structure image, as in the optical structure observation device according to claim 10. A reference layer extracting means for extracting at least a mucosal muscle plate of the layer as a reference layer, a reference layer flattening means for flattening the reference layer, and reconstructing the optical three-dimensional structure image as the flattened reference layer, A structure image converting means for generating a three-dimensional converted light structure image, wherein the extraction region setting means has a desired depth in the mucosa layer parallel to the reference layer on the three-dimensional converted light structure image. It is preferable to set an extraction region having a parallel plane as a plane located on the side.

  The optical structure observation apparatus according to claim 10, wherein the presence or absence of a lesioned part of the mucosal muscle plate is determined and the lesioned part is present, as in the optical structure observation apparatus according to claim 11. It is preferable to further include a mucosal muscular lesion lesion determining unit that extracts a lesion region, and a lesion region superimposing unit that generates a region image of the lesion region and superimposes the region image on the parallel sectional image.

  The structure information processing method of the optical structure observation apparatus according to claim 12, wherein the second direction orthogonal to the first direction and the first direction that is the depth direction of the measurement target having the mucosal layer using the low interference light is used. A plurality of acquired optical structure information of the measurement object obtained by scanning a scan plane consisting of a plurality of directions while shifting a position along a third direction that is a direction substantially orthogonal to the scan plane. In a structure information processing method of an optical structure observation apparatus that constructs an optical three-dimensional structure image based on the optical structure information of the optical structure information by comparing an information value of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold value A glandular cavity extraction step for extracting a glandular cavity of the mucosal layer, an extraction region setting step for setting an extraction region having a plane parallel to the plane in the mucosal layer, and the extraction region set in the extraction region setting step Optical structure A region information calculation step for performing a predetermined calculation on the information, a parallel cross-sectional image generation step for generating a parallel cross-sectional image based on the calculation result of the region information calculation step, and the gland extracted by the glandular cavity extraction step And a color tone editing step for editing the color tone of the parallel sectional image based on the cavity.

  13. The structure information processing method of the optical structure observation apparatus according to claim 12, wherein the mucosal layer is obtained by comparing information values of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold in the glandular cavity extraction step. In the extraction region set in the extraction region setting step, the extraction region setting step sets the extraction region having the plane in the mucosa layer as a parallel section, and the region information calculation step sets the extraction region A predetermined calculation is performed on the optical structure information, a parallel cross-sectional image based on the calculation result of the region information calculation step is generated in the parallel cross-sectional image generation step, and the glandular cavity is further calculated in the color tone editing step. Based on the glandular cavities extracted in the extraction step, by editing the color tone of the parallel sectional image, the three-dimensional structure of the gland duct structure is analyzed, and the internal state of the measurement object having the gland duct structure is analyzed. The makes it possible to easily diagnose the desired tone color image reflecting the.

  The structure information processing method of the optical structure observation apparatus according to claim 12, as in the structure information processing method of the optical structure observation apparatus according to claim 13, wherein the color editing step includes a preset color map. It is preferable to edit the color tone of the parallel sectional image based on the above.

  15. The structure information processing method of the optical structure observation apparatus according to claim 13, as in the structure information processing method of the optical structure observation apparatus according to claim 14, wherein the color map is indigo carmine, crystal violet, methylene blue. It is preferable to specify the color tone of at least one dye.

  The structure information processing method of the optical structure observation apparatus according to claim 13 or 14, as in the structure information processing method of the optical structure observation apparatus according to claim 15, wherein the color tone specified by the color map is the predetermined color tone. It is preferable to provide a color tone switching step for switching based on the threshold value.

  The structure information processing method of the optical structure observation device according to claim 15, as in the structure information processing method of the optical structure observation device according to claim 16, wherein the color tone switching step includes the plane in the mucous membrane layer. Preferably, the color tone specified by the color map is switched based on a plurality of sets of the predetermined threshold values corresponding to the depth position.

  The structure information processing method of the optical structure observation apparatus according to any one of claims 12 to 16, as in the structure information processing method of the optical structure observation apparatus according to claim 17, wherein the region information calculation step The predetermined calculation executed by is performed by any one of an integration process, a maximum value projection process, and a minimum value projection process that executes the optical structure information in the extraction region along a direction orthogonal to the plane. It is preferable to be an operation.

  The structure information processing method of the optical structure observation apparatus according to any one of claims 12 to 17, as in the structure information processing method of the optical structure observation apparatus according to claim 18, wherein the extraction region setting step Sets a plurality of extraction regions composed of different regions each having a plurality of parallel surfaces located at a plurality of desired heights parallel to the plane as parallel sections, and the region information calculation step includes the plurality of extractions. It is preferable that the predetermined calculation is performed for each region, and the parallel slice image generation step generates a plurality of the parallel slice images based on a calculation result for each of the plurality of extraction regions.

  A structure information processing method for an optical structure observation device according to claim 18, as in the structure information processing method for an optical structure observation device according to claim 19, wherein a composite image obtained by synthesizing a plurality of the parallel sectional images is obtained. It is preferable to further include an image composition step to be generated.

  A structure information processing method for an optical structure observation apparatus according to any one of claims 12 to 19, as in the structure information processing method for an optical structure observation apparatus according to claim 20, wherein Preferably, the method further includes a two-dimensional region designation step for designating an arbitrary two-dimensional region and an image enlargement step for generating an enlarged image obtained by enlarging the image of the two-dimensional region.

  A structure information processing method for an optical structure observation device according to any one of claims 12 to 20, as in the structure information processing method for an optical structure observation device according to claim 21, wherein the optical three-dimensional structure image is obtained. A reference layer extraction step for extracting at least a mucosal muscle plate of the mucosal layer as a reference layer from the optical structure information constituting the reference layer, a reference layer flattening step for flattening the reference layer, and a flattened reference layer A structure image converting step of reconstructing the optical three-dimensional structure image to generate a three-dimensional converted light structure image, wherein the extraction region setting step includes the reference layer on the three-dimensional converted light structure image. It is preferable to set an extraction region in which a plane located at a desired depth in the mucosal layer parallel to the parallel section is the parallel section.

  23. The structure information processing method of the optical structure observation apparatus according to claim 21, as in the structure information processing method of the optical structure observation apparatus according to claim 22, wherein the presence or absence of a lesioned part of the mucosal muscle plate is determined. A mucosal muscular lesion lesion determining step for extracting a lesion area when the lesion area is present; a lesion area superimposing step for generating an area image of the lesion area and superimposing the area image on the parallel sectional image; It is preferable to further provide.

  The endoscope system according to claim 23, a first light source that emits low-interference light, a first direction that is a depth direction of a measurement target having a mucosal layer using the low-interference light, and the first A plurality of pieces of optical structure information of the measurement object obtained by scanning a scan plane composed of a second direction orthogonal to the direction of the image while shifting the position along a third direction that is a direction substantially orthogonal to the scan plane An optical structure observation apparatus having an optical probe to be acquired, and an optical structure information processing apparatus that constructs an optical three-dimensional structure image based on the plurality of acquired optical structure information, a second light source that emits illumination light, and the illumination An endoscope having an imaging means for imaging the measurement object using light at the distal end of the insertion portion and having a treatment instrument channel for inserting the optical probe into the insertion portion, and an image pickup signal from the imaging means. To generate an endoscopic image In an endoscope system including an endoscope apparatus including a mirror processor, the optical structure observation apparatus compares the information value of the optical structure information constituting the optical stereoscopic structure image with a predetermined threshold value. A glandular cavity extracting means for extracting the glandular cavity of the mucosal layer, an extraction area setting means for setting an extraction area having a plane parallel to the plane in the mucosal layer, and an extraction area in the extraction area set by the extraction area setting means Extracted by the area information calculation means for executing a predetermined calculation on the optical structure information, the parallel cross-section image generation means for generating a parallel cross-section image based on the calculation result of the area information calculation means, and the glandular cavity extraction means And color tone editing means for editing the color tone of the parallel sectional image based on the glandular cavity.

  As described above, according to the present invention, the three-dimensional structure of the gland duct structure is analyzed, and the internal state of the measurement target having the gland duct structure is easily diagnosed by the color image reflecting the desired color tone. There is an effect that can be done.

1 is an external view showing a diagnostic imaging apparatus according to a first embodiment. The block diagram which shows the internal structure of the OCT processor of FIG. Sectional view of the OCT probe of FIG. The figure which shows a mode that optical structure information is obtained using the OCT probe derived | led-out from the forceps opening | mouth of the endoscope of FIG. The block diagram which shows the structure of the process part of FIG. The flowchart which shows the flow of an effect | action of the process part of the OCT processor of FIG. The 1st figure which shows the three-dimensional structure of the gland duct which the glandular cavity extraction part of FIG. 5 extracts (quoting from nonpatent literature 1) 2nd figure which shows the three-dimensional structure of the gland duct which the glandular cavity extraction part of FIG. 5 extracts (cited from nonpatent literature 1) The figure explaining the setting of the extraction area by the extraction area setting part of FIG. The figure which shows an example of the parallel cross-section image which the parallel tomographic image generation part of FIG. 5 produced | generated. The figure which shows the example which set the linear cavity to the bluish green by the indigo carmine color tone by the color tone edit part of FIG. The figure which shows the example which set the color tone other than a linear cavity to purple color tone by crystal violet color tone by the color tone edit part of FIG. The block diagram which shows the structure of the process part of 2nd Embodiment. 14 is a flowchart showing a flow of operation of the processing unit of FIG. The figure for demonstrating the process of the reference | standard layer extraction part of FIG. The figure for demonstrating the process of the planarization process part of FIG. The 1st figure for demonstrating the process of the extraction area | region setting part of FIG. 2nd figure for demonstrating the process of the extraction area | region setting part of FIG. The figure which shows the color parallel cross-section image of the two extraction area | regions extracted by the process of FIG. 3rd figure for demonstrating the process of the extraction area | region setting part of FIG. The figure which shows the color parallel cross-section image of two extraction area | regions extracted by the process of FIG. The figure for demonstrating the process of the enlarged area setting part of FIG. 13, and an enlarged image production | generation part. The figure for demonstrating the process of the lesion determination part of FIG. The figure which shows the two-dimensional image produced | generated by the process of the lesion determination part of FIG. The figure which shows the color parallel cross-section image (composite image) on which the two-dimensional image was superimposed by the image synthetic | combination part of FIG. Diagram explaining the structure of the large intestine The figure explaining the gland duct formed in a mucosal layer substantially perpendicularly using the mucosal muscle plate of FIG. The figure which shows the deformation | transformation state by canceration of the gland duct of FIG. 27 (cited from nonpatent literature 1)

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First embodiment:
<Appearance of diagnostic imaging equipment>
FIG. 1 is an external view showing the diagnostic imaging apparatus according to the first embodiment.

  As shown in FIG. 1, in this embodiment, the diagnostic imaging apparatus 10 mainly includes an endoscope 100, an endoscope processor 200, a light source device 300, an OCT processor 400 as an optical structure observation device, and a monitor device 500. It is configured. Note that the endoscope processor 200 may be configured to incorporate the light source device 300, and constitutes an endoscope device together with the endoscope 100.

  The endoscope 100 includes a hand operation unit 112 and an insertion unit 114 that is connected to the hand operation unit 112. The surgeon grasps and operates the hand operation unit 112 and performs observation by inserting the insertion unit 114 into the body of the subject.

  The hand operation part 112 is provided with a forceps insertion part 138, and the forceps insertion part 138 communicates with the forceps port 156 of the distal end part 144. In the diagnostic imaging apparatus 10 according to the present invention, the OCT probe 600 is led out from the forceps port 156 by inserting the OCT probe 600 from the forceps insertion portion 138. The OCT probe 600 is inserted from the forceps insertion part 138 and inserted from the forceps port 156, an operation part 604 for the operator to operate the OCT probe 600, and the OCT processor 400 via the connector 410. It consists of a cable 606 to be connected.

<Configuration of endoscope, endoscope processor, and light source device>
[Endoscope]
At the distal end portion 144 of the endoscope 100, an observation optical system 150, an illumination optical system 152, and a CCD (not shown) are disposed.

  The observation optical system 150 forms an image of a subject on a light receiving surface (not shown) of the CCD, and the CCD converts the subject image formed on the light receiving surface into an electric signal by each light receiving element. The CCD of this embodiment is a color CCD in which three primary color red (R), green (G), and blue (B) color filters are arranged for each pixel in a predetermined arrangement (Bayer arrangement, honeycomb arrangement). It is.

[Light source device]
The light source device 300 causes visible light to enter a light guide (not shown). One end of the light guide is connected to the light source device 300 via the LG connector 120, and the other end of the light guide faces the illumination optical system 152. The light emitted from the light source device 300 is emitted from the illumination optical system 152 via the light guide, and illuminates the visual field range of the observation optical system 150.

[Endoscope processor]
An image signal output from the CCD is input to the endoscope processor 200 via the electrical connector 110. The analog image signal is converted into a digital image signal in the endoscope processor 200, and necessary processing for displaying on the screen of the monitor device 500 is performed.

  In this manner, observation image data obtained by the endoscope 100 is output to the endoscope processor 200, and an image is displayed on the monitor device 500 connected to the endoscope processor 200.

<Internal configuration of OCT processor and OCT probe>
FIG. 2 is a block diagram showing an internal configuration of the OCT processor of FIG.

[OCT processor]
An OCT processor 400 and an OCT probe 600 shown in FIG. 2 are for acquiring an optical tomographic image of the measuring object S by an optical coherence tomography (OCT) measurement method, and emit light La for measurement. The first light source (first light source unit) 12 and the light La emitted from the first light source 12 are branched into measurement light (first light flux) L1 and reference light L2, and a measurement target which is a subject. An optical fiber coupler (branching / combining unit) 14 that combines the return light L3 from S and the reference light L2 to generate interference light L4, and the measurement light L1 branched by the optical fiber coupler 14 is guided to the measurement target. In addition, the OCT probe 600 including the rotation-side optical fiber FB1 that guides the return light L3 from the measuring object S, and the measurement-light L1 is guided to the rotation-side optical fiber FB1 and the rotation-side optical fiber. The fixed side optical fiber FB2 that guides the return light L3 guided by the bar FB1 and the rotation side optical fiber FB1 are rotatably connected to the fixed side optical fiber FB2, and the measurement light L1 and the return light L3 are transmitted. The optical connector 18, the interference light detection unit 20 for detecting the interference light L 4 generated by the optical fiber coupler 14 as an interference signal, and processing the interference signal detected by the interference light detection unit 20 to obtain optical structure information. The processing unit 22 is obtained. In addition, an image generated based on the light structure information acquired by the processing unit 22 is displayed on the monitor device 500.

  In the present embodiment, for example, the large intestine mucosal tissue is the measurement target S, and the endoscope apparatus such as the endoscope 100 and the endoscope processor 200 uses the endoscopic image of the pit pattern on the mucosal surface of the large intestine. Further, the OCT processor 400 and the OCT probe 600 obtain a pit pattern image having a predetermined depth in the mucosa of the large intestine.

  The OCT processor 400 also includes a second light source (second light source unit) 13 that emits aiming light (second light flux) Le for indicating a mark of measurement, and an optical path that adjusts the optical path length of the reference light L2. A length adjusting unit 26, an optical fiber coupler 28 that splits the light La emitted from the first light source 12, and detection units 30a and 30b that detect return lights L4 and L5 combined by the optical fiber coupler 14, And an operation control unit 32 for inputting various conditions to the processing unit 22 and changing settings.

  In the OCT processor 400 shown in FIG. 2, various lights including the above-described emission light La, aiming light Le, measurement light L1, reference light L2, return light L3, and the like are guided between components such as optical devices. Various optical fibers FB (FB3, FB4, FB5, FB6, FB7, FB8, etc.) including the rotation-side optical fiber FB1 and the fixed-side optical fiber FB2 are used as light paths for wave transmission.

  The first light source 12 emits light for OCT measurement (for example, laser light having a wavelength of 1.3 μm or low coherence light), and the first light source 12 sweeps the frequency at a constant period. It is a light source that emits a laser beam La centered at a wavelength of 1.3 μm, for example, in the infrared region. The first light source 12 includes a light source 12a that emits laser light or low-coherence light La, and a lens 12b that condenses the light La emitted from the light source 12a. As will be described in detail later, the light La emitted from the first light source 12 is divided into the measurement light L1 and the reference light L2 by the optical fiber coupler 14 through the optical fibers FB4 and FB3, and the measurement light L1 is the light. Input to the connector 18.

  Further, the second light source 13 emits visible light so as to make it easy to confirm the measurement site as the aiming light Le. For example, red semiconductor laser light with a wavelength of 0.66 μm, He—Ne laser light with a wavelength of 0.63 μm, blue semiconductor laser light with a wavelength of 0.405 μm, or the like can be used. Therefore, the second light source 13 includes, for example, a semiconductor laser 13a that emits red, blue, or green laser light and a lens 13b that collects the aiming light Le emitted from the semiconductor laser 13a. The aiming light Le emitted from the second light source 13 is input to the optical connector 18 through the optical fiber FB8.

  In the optical connector 18, the measurement light L 1 and the aiming light Le are combined and guided to the rotation side optical fiber FB 1 in the OCT probe 600.

  The optical fiber coupler (branching / combining unit) 14 is composed of, for example, a 2 × 2 optical fiber coupler, and is optically connected to the fixed-side optical fiber FB2, the optical fiber FB3, the optical fiber FB5, and the optical fiber FB7, respectively. ing.

  The optical fiber coupler 14 splits the light La incident from the first light source 12 through the optical fibers FB4 and FB3 into measurement light (first light flux) L1 and reference light L2, and the measurement light L1 is fixed side light. The light is incident on the fiber FB2, and the reference light L2 is incident on the optical fiber FB5.

  Furthermore, the optical fiber coupler 14 is incident on the optical fiber FB5, is subjected to frequency shift and optical path length change by the optical path length adjusting unit 26 described later, and is returned by the optical fiber FB5 and acquired by the OCT probe 600 described later. Then, the light L3 guided from the fixed side optical fiber FB2 is multiplexed and emitted to the optical fiber FB3 (FB6) and the optical fiber FB7.

  The OCT probe 600 is connected to the fixed optical fiber FB2 via the optical connector 18, and the measurement light L1 combined with the aiming light Le is rotated from the fixed optical fiber FB2 via the optical connector 18. The light enters the side optical fiber FB1. The measurement light L1 combined with the incident aiming light Le is transmitted by the rotation side optical fiber FB1, and is irradiated to the measurement object S. Then, the return light L3 from the measuring object S is acquired, the acquired return light L3 is transmitted by the rotation side optical fiber FB1, and is emitted to the fixed side optical fiber FB2 via the optical connector 18.

  The optical connector 18 combines the measurement light (first light beam) L1 and the aiming light (second light beam) Le.

  The interference light detection unit 20 is connected to the optical fibers FB6 and FB7, and uses the interference lights L4 and L5 generated by combining the reference light L2 and the return light L3 by the optical fiber coupler 14 as interference signals. It is to detect.

  Here, the OCT processor 400 is provided on the optical fiber FB6 branched from the optical fiber coupler 28. The detector 30a detects the light intensity of the interference light L4, and the light of the interference light L5 on the optical path of the optical fiber FB7. And a detector 30b for detecting the intensity.

  The interference light detection unit 20 performs Fourier transform on the interference light L4 detected from the optical fiber FB6 and the interference light L5 detected from the optical fiber FB7 based on the detection results of the detectors 30a and 30b, thereby measuring the measurement target S. The intensity of the reflected light (or backscattered light) at each depth position is detected.

  From the interference signal extracted by the interference light detection unit 20, the processing unit 22 is a region where the OCT probe 600 and the measurement target S are in contact at the measurement position, more precisely, a probe outer cylinder (described later) of the OCT probe 600. A region where the surface and the surface of the measuring object S can be considered to be in contact with each other is detected, optical structure information is acquired from the interference signal detected by the interference light detection unit 20, and optical solids are obtained based on the acquired optical structure information. A structure image is generated, and an image obtained by performing various processes on the optical three-dimensional structure image is output to the monitor device 500. The detailed configuration of the processing unit 22 will be described later.

  The optical path length adjustment unit 26 is disposed on the emission side of the reference light L2 of the optical fiber FB5 (that is, the end of the optical fiber FB5 opposite to the optical fiber coupler 14).

  The optical path length adjustment unit 26 includes a first optical lens 80 that converts the light emitted from the optical fiber FB5 into parallel light, a second optical lens 82 that condenses the light converted into parallel light by the first optical lens 80, and The reflection mirror 84 that reflects the light collected by the second optical lens 82, the base 86 that supports the second optical lens 82 and the reflection mirror 84, and the base 86 are moved in a direction parallel to the optical axis direction. The optical path length of the reference light L2 is adjusted by changing the distance between the first optical lens 80 and the second optical lens 82.

  The first optical lens 80 converts the reference light L2 emitted from the core of the optical fiber FB5 into parallel light, and condenses the reference light L2 reflected by the reflection mirror 84 on the core of the optical fiber FB5.

  The second optical lens 82 condenses the reference light L2 converted into parallel light by the first optical lens 80 on the reflection mirror 84 and makes the reference light L2 reflected by the reflection mirror 84 parallel light. Thus, the first optical lens 80 and the second optical lens 82 form a confocal optical system.

  Further, the reflection mirror 84 is disposed at the focal point of the light collected by the second optical lens 82 and reflects the reference light L2 collected by the second optical lens 82.

  As a result, the reference light L2 emitted from the optical fiber FB5 becomes parallel light by the first optical lens 80 and is condensed on the reflection mirror 84 by the second optical lens 82. Thereafter, the reference light L2 reflected by the reflection mirror 84 becomes parallel light by the second optical lens 82 and is condensed by the first optical lens 80 on the core of the optical fiber FB5.

  The base 86 fixes the second optical lens 82 and the reflecting mirror 84, and the mirror moving mechanism 88 moves the base 86 in the optical axis direction of the first optical lens 80 (the direction of arrow A in FIG. 2). .

  By moving the base 86 in the direction of arrow A with the mirror moving mechanism 88, the distance between the first optical lens 80 and the second optical lens 82 can be changed, and the optical path length of the reference light L2 can be adjusted. Can do.

  The operation control unit 32 as an extraction region setting unit and a two-dimensional region designation unit includes an input unit such as a keyboard and a mouse, and a control unit that manages various conditions based on the input information. It is connected. The operation control unit 32 inputs, sets, and changes various processing conditions and the like in the processing unit 22 based on an operator instruction input from the input unit.

  Note that the operation control unit 32 may display the operation screen on the monitor device 500, or may provide a separate display unit to display the operation screen. In addition, the operation control unit 32 controls the operation of the first light source 12, the second light source 13, the optical connector 18, the interference light detection unit 20, the optical path length, the detection units 30a and 30b, and sets various conditions. May be.

[OCT probe]
FIG. 3 is a cross-sectional view of the OCT probe of FIG.

  As shown in FIG. 3, the distal end portion of the insertion portion 602 has a probe outer cylinder 620, a cap 622, a rotation side optical fiber FB 1, a spring 624, a fixing member 626, and an optical lens 628. .

  The probe outer cylinder (sheath) 620 is a flexible cylindrical member and is made of a material through which the measurement light L1 combined with the aiming light Le and the return light L3 are transmitted in the optical connector 18. The probe outer cylinder 620 is a tip through which the measurement light L1 (aiming light Le) and the return light L3 pass (the tip of the rotation side optical fiber FB1 opposite to the optical connector 18, hereinafter referred to as the tip of the probe outer cylinder 620). It is only necessary that a part of the side is made of a material that transmits light over the entire circumference (transparent material), and parts other than the tip may be made of a material that does not transmit light.

  The cap 622 is provided at the distal end of the probe outer cylinder 620 and closes the distal end of the probe outer cylinder 620.

  The rotation side optical fiber FB1 is a linear member, is accommodated in the probe outer cylinder 620 along the probe outer cylinder 620, is emitted from the fixed side optical fiber FB2, and is emitted from the optical fiber FB8 by the optical connector 18. The measurement light L1 combined with the aiming light Le is guided to the optical lens 628, and the measurement object L is irradiated with the measurement light L1 (aiming light Le) to return from the measurement object S acquired by the optical lens 628. The light L3 is guided to the optical connector 18 and enters the fixed optical fiber FB2.

  Here, the rotation-side optical fiber FB1 and the fixed-side optical fiber FB2 are connected by the optical connector 18, and are optically connected in a state where the rotation of the rotation-side optical fiber FB1 is not transmitted to the fixed-side optical fiber FB2. ing. The rotation-side optical fiber FB1 is disposed so as to be rotatable with respect to the probe outer cylinder 620 and movable in the axial direction of the probe outer cylinder 620.

  The spring 624 is fixed to the outer periphery of the rotation side optical fiber FB1. The rotation side optical fiber FB1 and the spring 624 are connected to the optical connector 18.

  The optical lens 628 is disposed at the measurement-side tip of the rotation-side optical fiber FB1 (tip of the rotation-side optical fiber FB1 opposite to the optical connector 18), and the tip is measured from the rotation-side optical fiber FB1. In order to collect the light L1 (aiming light Le) with respect to the measuring object S, it is formed in a substantially spherical shape.

  The optical lens 628 irradiates the measurement target S with the measurement light L1 (aiming light Le) emitted from the rotation side optical fiber FB1, collects the return light L3 from the measurement target S, and enters the rotation side optical fiber FB1. .

  The fixing member 626 is disposed on the outer periphery of the connection portion between the rotation side optical fiber FB1 and the optical lens 628, and fixes the optical lens 628 to the end portion of the rotation side optical fiber FB1. Here, the fixing method of the rotation side optical fiber FB1 and the optical lens 628 by the fixing member 626 is not particularly limited, and the fixing member 626, the rotation side optical fiber FB1 and the optical lens 628 are bonded and fixed by an adhesive. Alternatively, it may be fixed with a mechanical structure using a bolt or the like. The fixing member 626 may be any member as long as it is used for fixing, holding or protecting the optical fiber such as a zirconia ferrule or a metal ferrule.

  The rotation side optical fiber FB1 and the spring 624 are connected to a rotation cylinder 656, which will be described later. By rotating the rotation side optical fiber FB1 and the spring 624 by the rotation cylinder 656, the optical lens 628 is moved to the probe outer cylinder 620. On the other hand, it is rotated in the direction of arrow R2. The optical connector 18 includes a rotary encoder, and detects the irradiation position of the measurement light L1 from the position information (angle information) of the optical lens 628 based on a signal from the rotary encoder. That is, the measurement position is detected by detecting the angle of the rotating optical lens 628 with respect to the reference position in the rotation direction.

  Further, the rotation side optical fiber FB1, the spring 624, the fixing member 626, and the optical lens 628 are moved through the probe outer cylinder 620 in the arrow S1 direction (forceps opening direction) and the S2 direction (probe outer cylinder 620) by a driving unit described later. It is configured to be movable in the direction of the tip.

  Further, the left side of FIG. 3 is a diagram showing an outline of a drive unit such as the rotation side optical fiber FB1 in the operation unit 604 of the OCT probe 600.

  The probe outer cylinder 620 is fixed to a fixing member 670. On the other hand, the rotation side optical fiber FB1 and the spring 624 are connected to a rotating cylinder 656, and the rotating cylinder 656 is configured to rotate via a gear 654 in accordance with the rotation of the motor 652. The rotary cylinder 656 is connected to the optical connector 18, and the measurement light L1 and the return light L3 are transmitted between the rotation side optical fiber FB1 and the fixed side optical fiber FB2 via the optical connector 18.

  Further, the frame 650 containing these includes a support member 662, and the support member 662 has a screw hole (not shown). A forward and backward movement ball screw 664 is engaged with the screw hole, and a motor 660 is connected to the forward and backward movement ball screw 664. Therefore, the frame 650 can be moved forward and backward by rotationally driving the motor 660, whereby the rotation side optical fiber FB1, the spring 624, the fixing member 626, and the optical lens 628 can be moved in the S1 and S2 directions in FIG. It has become.

  The OCT probe 600 is configured as described above, and the measurement side light L1 emitted from the optical lens 628 is obtained by rotating the rotation-side optical fiber FB1 and the spring 624 in the direction of the arrow R2 in FIG. (Aiming light Le) is irradiated to the measuring object S while scanning in the arrow R2 direction (circumferential direction of the probe outer cylinder 620), and the return light L3 is acquired. The aiming light Le is irradiated to the measuring object S as, for example, blue, red, or green spot light, and the reflected light of the aiming light Le is also displayed as a bright spot on the observation image displayed on the monitor device 500.

  Thereby, the desired site | part of the measuring object S can be caught correctly in the perimeter of the circumference direction of the probe outer cylinder 620, and the return light L3 which reflected the measuring object S can be acquired.

  Further, when acquiring a plurality of optical structure information for generating an optical three-dimensional structure image, the optical lens 628 is moved to the end of the movable range in the arrow S1 direction by the driving unit, and the optical structure information including the tomographic image is obtained. While acquiring, it moves in the S2 direction by a predetermined amount, or moves to the end of the movable range while alternately repeating the acquisition of optical structure information and the predetermined amount of movement in the S2 direction.

  In this manner, a plurality of pieces of optical structure information in a desired range can be obtained for the measurement object S, and an optical three-dimensional structure image can be obtained based on the obtained plurality of pieces of optical structure information.

  That is, the optical structure information in the depth direction (first direction) of the measurement target S is acquired from the interference signal, and the measurement target S is scanned in the direction of arrow R2 in FIG. 3 (circumferential direction of the probe outer cylinder 620). Thus, it is possible to acquire the optical structure information on the scan plane composed of the first direction and the second direction orthogonal to the first direction, and further, the third direction orthogonal to the scan plane. A plurality of pieces of optical structure information for generating an optical three-dimensional structure image can be acquired by moving the scan plane along the line.

  FIG. 4 is a diagram showing how optical structure information is obtained using an OCT probe derived from the forceps opening of the endoscope of FIG. As shown in FIG. 4, the optical structure information is obtained by bringing the distal end portion of the insertion portion 602 of the OCT probe close to a desired portion of the measurement target S. When acquiring a plurality of pieces of optical structure information in a desired range, it is not necessary to move the OCT probe 600 main body, and the optical lens 628 may be moved within the probe outer cylinder 620 by the driving unit described above.

[Processing part]
FIG. 5 is a block diagram showing a configuration of the processing unit of FIG.

  As shown in FIG. 5, the processing unit 22 of the OCT processor 400 includes an optical structure information detection unit 220, a glandular cavity extraction unit 221 as a glandular cavity extraction unit and a color tone switching unit, a threshold storage unit 222, and an extraction region setting unit. Extraction region setting unit 223, region information calculation unit 224 as region information calculation unit, parallel tomographic image generation unit 225 as parallel tomographic image generation unit, color map storage unit 226, color tone editing unit 227 as color tone editing unit, display control A unit 228 and an I / F unit 229 are provided.

  The optical structure information detection unit 220 detects optical structure information from the interference signal detected by the interference light detection unit 20 and generates an optical three-dimensional structure image.

  The glandular cavity extraction unit 221 extracts the glandular cavity of the gland duct inside the measuring object S (mucosal tissue of the large intestine) from the optical structure information detected by the optical structure information detection unit 220 as three-dimensional structure information.

  The threshold storage unit 222 is a memory that stores, for example, table data, a plurality of predetermined thresholds for the glandular cavity extraction unit 221 to extract the glandular cavity of the gland duct from the optical structure information.

  The extraction region setting unit 223 sets a region in the measurement target S (colon mucosa tissue) to be calculated by the region information calculation unit 224 in accordance with a setting signal from the operation control unit 32 via the I / F unit 229. In this case, an extraction region having a thickness in the depth direction of the measurement target S having a plane parallel to the surface of the mucosa or the mucosal muscle plate in the measurement target S (colon mucosa tissue) is set.

  The region information calculation unit 224 is a calculation processing unit that performs a predetermined calculation on the extraction region set by the extraction region setting unit 223, and the extraction region setting unit extracts the optical structure information of the region extraction region. Integration processing is performed along the depth direction (first direction) of the measuring object S orthogonal to the plane used in the above. The calculation process executed by the area information calculation unit 224 is not limited to the integration process. For example, the depth direction of the measurement target S orthogonal to the plane used by the extraction area setting unit to extract the optical structure information of the area extraction area Any one of MIP (Maximum intensity projection) and MINIP (Minimum intensity projection) may be performed. The parallel tomographic image generation unit 225 generates a parallel cross-sectional image that is an integrated image in which a pit pattern appears by, for example, integration processing executed by the region information calculation unit 224. The parallel tomographic image generated by the parallel tomographic image generation unit 225 may be a cross-sectional image of the extraction region without performing processing such as integration processing, maximum value projection processing, and minimum value projection processing.

  For example, the color map storage unit 226 switches color information for setting the color tone of the parallel sectional image based on a predetermined threshold value used for extracting the three-dimensional structure information of the glandular cavity from the glandular cavity extraction unit 221. This is a storing memory unit.

  Based on the three-dimensional structure information of the glandular cavities extracted by the glandular cavity extraction unit 221, the color tone editing unit 227 generates the parallel tomographic image generation unit 225 using the color tone information stored in the color map storage unit 226. The color tone of the parallel cross-sectional image obtained is edited.

  The display control unit 228 displays the image of the extraction region from the extraction region setting unit 223, the parallel tomographic image before color tone editing from the parallel tomographic image generation unit 225, and the parallel tomographic image after color tone editing from the color tone editing unit 227, respectively. , And selectively output to the monitor device 500 by a designation signal from the operation control unit 32 via the I / F unit 229.

  The I / F unit 229 is a communication interface unit that transmits a setting signal and a designation signal from the operation control unit 32 to each unit. The operation of the OCT processor 400 as the optical structure observation apparatus of the present embodiment configured as described above will be described with reference to FIGS. 7 to 12 using the flowchart of FIG.

  FIG. 6 is a flowchart showing a flow of operation of the processing unit of the OCT processor of FIG. 1, and FIGS. 7 to 12 are diagrams for explaining the processing of FIG.

  The surgeon turns on the power to each part of the endoscope 100, the endoscope processor 200, the light source device 300, the OCT processor 400, and the monitor device 500, and the OCT probe 600 led out from the forceps opening of the endoscope 100. For example, the distal end portion of the insertion portion 602 is brought close to the mucous membrane (measurement target S) of the large intestine, and optical scanning is started by the OCT probe 600.

  As illustrated in FIG. 6, the processing unit 22 of the OCT processor 400 detects optical structure information on the scan plane constituting the tomographic image from the interference signal detected by the optical structure information detection unit 220 by the interference light detection unit 20. (Step S1).

  The processing unit 22 then measures the measurement target S (mucosal tissue of the large intestine) from the optical structure information detected by the optical structure information detection unit 220 based on the predetermined threshold value stored in the threshold value storage unit 222 by the glandular cavity extraction unit 221. The glandular cavity of the internal gland duct is extracted as three-dimensional structure information (step S2). 7 and 8 show an example of the three-dimensional structure of the gland duct extracted by the glandular cavity extraction unit of FIG. 5, and FIG. 7 shows the three-dimensional structure of the type I gland duct corresponding to the I-type pit pattern. 8 shows the three-dimensional structure of the IV type gland duct corresponding to the IV type pit pattern.

  The threshold storage unit 222 stores a predetermined threshold set in advance corresponding to the information value (signal intensity) of the optical structure information detected by the optical structure information detection unit 220. Since the lumen of the gland duct is filled with mucus, a difference appears in the information value (signal intensity) of the optical structure information between the lumen and other parts. Therefore, the glandular cavity extraction unit 221 extracts a linear cavity by comparing a predetermined threshold value stored in advance in the threshold value storage unit 222 with the information value (signal intensity) of the optical structure information.

  Next, the processing unit 22 causes the extraction region setting unit 223 to perform calculation in the region information calculation unit 224 based on the setting signal from the operation control unit 32 via the I / F unit 229. For example, the measurement target S (large intestine) In the region from the mucosal surface to the mucosal muscle plate in the mucosa tissue), an extraction region having a thickness is set in the depth direction of the measurement object S with the plane in the measurement object S (mucosal tissue of the large intestine) being a parallel section ( Step S3).

  FIG. 9 is a diagram illustrating the setting of the extraction region by the extraction region setting unit in FIG. 5. Specifically, in step S3, the extraction region setting unit 223 displays the (first direction and the first direction). The optical structure information detected by the optical structure information detection unit 220 on the scan plane 920 (consisting of a second direction orthogonal to each other) is displayed on the monitor device 500, and the optical structure information on the scan plane 920 is displayed as shown in FIG. Then, the operation control unit 32 sets an extraction region 970 that is a certain range in the region from the mucosal surface 921 to the mucosal muscle plate 950.

  Then, with respect to the extraction region set in the extraction region setting unit 223 by the region information calculation unit 224, the processing unit 22 sets the optical structure information of the region extraction region on the plane used for the setting by the extraction region setting unit. Integration processing is performed along the depth direction of the measurement object S that is orthogonal (step S4).

  Next, the processing unit 22 generates a parallel cross-sectional image that is an integrated image in which a pit pattern appears by, for example, integration processing executed by the region information calculation unit 224 (step S5). FIG. 10 is a diagram illustrating an example of a parallel cross-sectional image generated by the parallel tomographic image generation unit of FIG.

  Then, the processing unit 22 is stored in the color map storage unit 226 based on the three-dimensional structure information (see FIGS. 7 and 8) of the glandular cavity extracted in the glandular cavity extraction unit 221 by the color tone editing unit 227. The color tone of the parallel slice image generated by the parallel tomographic image generation unit 225 is edited using the existing color tone information (step S6), and the process ends.

  11 is a diagram showing an example in which the color cavity is set to blue-green by the indigo carmine color tone by the color tone editing unit of FIG. 5, and FIG. 12 is a purple color tone other than the line cavity by the crystal violet color tone by the color tone editing unit of FIG. It is a figure which shows the example set to.

  The color tone editing unit 227 applies a color map stored in advance in the color map storage unit 226 to the horizontal section image 975 in accordance with a predetermined threshold value used for extraction of the three-dimensional structure information of the ducts. And the color tone of the parallel slice image as shown in FIG. 12 is edited to generate a color parallel slice image 990. Specifically, based on a predetermined threshold value used for extraction of the three-dimensional structure information of the linear cavity extracted by the glandular cavity extraction unit 221, in the parallel cross-sectional image (see FIG. 10), for example, as indigo carmine pigment In the case of a correct color tone (hereinafter referred to as indigo carmine color tone), the linear cavity region 980 is set to a blue-green color tone (see FIG. 11), and in the case of a color tone like a crystal violet pigment (hereinafter referred to as crystal violet color tone) A region 981 other than the region 980 is set to a purple color tone (see FIG. 12).

  In addition to the indigo carmine color tone and the crystal violet color tone, the color map storage unit 226 stores color tone information of at least a color tone such as methylene blue pigment (hereinafter referred to as methylene blue color tone).

  Thus, in the present embodiment, a three-dimensional structure of the gland duct is used by using a color map that is stored in advance in the color map storage unit 226 and includes color information such as indigo carmine color tone, crystal violet color tone, and methylene blue color tone. Accordingly, the color parallel slice image 990 is generated by editing the color tone of the parallel slice image, so that the pit pattern structure inside the living body is similar to the conventional two-dimensional pit pattern observation of the mucosal surface by an endoscope. Can be observed.

  That is, according to the present embodiment, the three-dimensional structure of the duct structure is analyzed with a predetermined threshold, and the internal state (pit pattern) of the measurement target having the duct structure is changed to a desired color tone based on the predetermined threshold. It can be obtained as a reflected image, and the internal state of the measurement object can be easily diagnosed with the same visibility as a conventional two-dimensional pit pattern on the mucosal surface by an endoscope.

  For example, a color parallel cross-sectional image 990 (in-vivo internal pit pattern) having a three-dimensional structure inside a living body such as a large intestine gland duct can be clearly observed in the same manner as a mucosal surface pit pattern observation by a conventional endoscope. Furthermore, since the observation is performed with the same color tone as that of the conventional mucosal surface pit pattern, the operator observes the color parallel cross-sectional image 990 (in-vivo internal pit pattern) with a three-dimensional gland duct structure without any discomfort. can do.

  Note that the color tone information may be color tone information such as a mixture of the pigment and the dye. The color tone information is not limited to the color tone information. For example, desired color tone information is stored in the color map storage unit 226 based on a color tone setting signal from the operation control unit 32, and a threshold setting signal is output from the operation control unit 32. Thus, a desired threshold value may be stored in the threshold value storage unit 222, and the color tone of the parallel slice image may be switched according to the threshold value and color tone information set by the operator.

  Further, the predetermined threshold value for extracting the linear cavity may be changed according to the color map to be adapted, or may be changed according to the height position (the depth direction of the living body) from which the horizontal section image is extracted. For example, a plurality of predetermined threshold values and a plurality of color tones can be set in association with the height position (in the depth direction of the living body) at which the horizontal section image is extracted as shown in Table 1.

  In this embodiment, not only the pit pattern on the mucosal surface but also the pit pattern (pit structure) inside the living body can be observed from the color parallel cross-sectional image 990, so that the pit pattern on the mucosal surface is difficult to diagnose. Accurate cases can be diagnosed accurately by the pit pattern (pit structure) inside the living body. In addition, the present embodiment is an observation using the color parallel cross-sectional image 990, and does not actually use a pigment. Therefore, the color parallel cross-sectional image 990 is not affected by mucus, a lesion state, a dispersion technique, or the like. It is also possible to observe the pit pattern on the mucosal surface 921.

Second embodiment:
Since this embodiment is almost the same as the first embodiment, only different points will be described, the same components are denoted by the same reference numerals, and description thereof will be omitted.

  FIG. 13 is a block diagram illustrating a configuration of a processing unit according to the second embodiment.

  As shown in FIG. 13, the processing unit 22 of the second embodiment includes an optical structure information detection unit 220, a glandular cavity extraction unit 221, a threshold storage unit 222, an extraction region setting unit 223, a region information calculation unit 224, a parallel tomography. In addition to the components of the image generation unit 225, the color map storage unit 226, the color tone editing unit 227, the display control unit 228, and the I / F unit 229, the reference layer extraction unit 231, the flattening processing unit 232, and the optical three-dimensional structure image conversion A unit 233, a lesion determination unit 235, an image composition unit 236, an enlarged region setting unit 237, and an enlarged image generation unit 238.

  In the optical structure information on the scan plane, for example, when the measurement target S is the large intestine mucosa, the reference layer extraction unit 231 extracts a mucosal muscle plate as a reference layer. When the mucosal epithelium such as the esophagus is a squamous epithelium, the reference layer extraction unit 231 extracts a basement membrane (basement layer) as a reference layer. The reference layer extraction unit 231 can extract the mucosal surface as a reference layer. The reference layer can be set by a setting signal from the operation control unit 32 via the I / F unit 229.

  The flattening processing unit 232 shifts the data in the depth direction so that the extracted mucosal muscle plate becomes a certain reference position in order to flatten the layer position of the mucosal muscle plate extracted by the reference layer extracting unit 231. It is something to be made. Note that the flattening processing unit 232 may be configured to perform the flattening process by fitting the position of the mucosal muscle plate to an arbitrary function from the two-dimensional light structure information or the three-dimensional light structure information. .

  The light three-dimensional structure image converting unit 233 converts the light three-dimensional structure image generated by the light structure information detecting unit 220 so that the flattened mucosal muscle plate becomes a reference plane of the light three-dimensional structure image.

  The reference plane is not limited to the mucosal muscular plate, but may be the mucosal surface or the basal layer (when the mucosal epithelium is a squamous epithelium).

  The lesion determination unit 235 determines the presence or absence of a so-called lesion part in which tissue is missing on the flattened mucosal muscle plate in the optical three-dimensional structure image conversion unit 233, and if there is a lesion part, extracts the lesion area To do.

  In the present embodiment, the extraction area setting unit 223 can set a plurality of extraction areas. Also in the first embodiment, the extraction region setting unit 223 can set a plurality of extraction regions.

  The image composition unit 236, when a plurality of extraction regions are set by the extraction region setting unit 223 according to the setting signal of the operation control unit 32 via the I / F unit 229, parallel tomographic images corresponding to the plurality of extraction regions. A plurality of parallel slice images generated by the generation unit 225 are combined, or a lesion area extracted by the lesion determination unit 235 is superimposed on the parallel slice images.

  The enlarged area setting unit 237 sets an enlarged area to be enlarged and displayed on the parallel cross-sectional image, and the enlarged image generation unit 238 generates an enlarged image obtained by enlarging the enlarged area.

  In the present embodiment, the display control unit 228 includes the image of the extraction region from the extraction region setting unit 223, the parallel tomographic image before color tone editing from the parallel tomographic image generation unit 225, and the parallel after color tone editing from the color tone editing unit 227. Each of the tomographic image and the synthesized image from the image synthesizing unit 236 and the enlarged image from the enlarged image generating unit 238 are selectively output to the monitor device 500 by a designation signal from the operation control unit 32 via the I / F unit 229. To do.

  Other configurations are the same as those of the first embodiment.

  The operation of the OCT processor 400 as the optical structure observation apparatus of the present embodiment configured as described above will be described with reference to FIGS. 15 to 25 using the flowchart of FIG. FIG. 14 is a flowchart showing the flow of operation of the processing unit of FIG. 13, and FIGS. 15 to 25 are diagrams for explaining the processing of FIG.

  In the OCT processor 400 of this embodiment, as shown in FIG. 14, the processing unit 22 performs the optical control of the display control unit 228 after the processing in steps S <b> 1 and S <b> 2 (see FIG. 6) described in the first embodiment. The optical structure information on the scan plane 920 constituting the optical three-dimensional structure image generated by the information detection unit 220 is displayed on the monitor device 500, and the reference layer extraction unit 231 uses, for example, measurement in the optical structure information on the scan plane 920. If the target S is the mucosa of the large intestine, the mucosal muscle plate 950 is extracted as the reference layer (step S21).

  FIG. 15 is a diagram for explaining the processing of the reference layer extraction unit of FIG. Specifically, the reference layer extraction unit 231 extracts the mucosal muscle plate by analyzing the optical structure information (image signal intensity). That is, in the reference layer extraction unit 231, as shown in FIG. 15, the portion 951 a having the strong first optical structure information (image signal intensity) is the mucosal surface 951 on the scan plane 920 constituting the optical three-dimensional structure image. It is determined that the portion 950a having the strong image signal intensity corresponds to the mucosal muscle 950, and the entire scanning surface 920 is scanned to extract the layer position of the mucosal muscle 950.

  Then, in the processing unit 22, the flattening processing unit 232 sets the extracted mucosal muscle 950 to a certain reference position O in order to flatten the layer position of the mucosal muscle 950 extracted by the reference layer extraction unit 231. The optical structure information in the depth direction is shifted so as to make the mucosal muscle plate 950 flat as shown in FIG. 16 (step S22).

  Subsequently, in the processing unit 22, the optical three-dimensional structure image conversion unit 233 reconstructs the optical three-dimensional structure image so that the mucosal muscle 950 flattened by the flattening processing unit 232 becomes the reference plane of the optical three-dimensional structure image. (Step S23).

  Next, the processing unit 22 determines the presence or absence of a so-called lesioned part in which a tissue is missing on the flattened mucosal muscle plate in the optical three-dimensional structure image converting unit 233 in the lesion judging unit 235, and there is a lesioned part. If so, the lesion area is extracted (step S24). Details of this processing will be described later.

  Then, the processing unit 22 executes the processing of steps S3 to S6 (see FIG. 6) described in the first embodiment, and then the operation control unit 32 via the I / F unit 229 in the image composition unit 236. When a plurality of extraction regions are set by the extraction region setting unit 223 according to the setting signal, a plurality of parallel sectional images generated by the parallel tomographic image generation unit 225 corresponding to the plurality of extraction regions are combined, or a lesion determination unit The lesion area extracted by 235 is superimposed on the parallel slice image (step S25).

  In this embodiment, in step S3, as shown in FIG. 17, the extraction region setting unit 223 is on the scan plane 920 on the mucosal muscle 950 where one extraction region 970 is flattened as in the first embodiment, for example. However, as shown in FIG. 18, for example, two extraction regions 970a and 970b can be set at different depths.

  When these two extraction areas 970a and 970b are set, in this embodiment, as shown in FIG. 19, a color obtained by editing the color tone of the parallel sectional images of the respective extraction areas 970a and 970b by the processing in steps S4 to S6. Parallel cross-sectional images 990a and 990b are generated. The color parallel slice image 990a is an image of the upper layer extraction region 970a, and the color parallel slice image 990b is an image of the upper layer extraction region 970b. The color parallel cross-sectional images 990a and 990b are examples in which the color tone is edited by the crystal violet color tone and the region 981 other than the linear cavity region 980 is set to a purple color tone. In this case, the line cavity region 980 of the color parallel cross-sectional image 990a has a larger shape than the line cavity region 980 of the color parallel cross-sectional image 990b, but the pit patterns are both substantially circular regular arrays, It can be easily determined that the gland duct has a normal type I structure in the extraction regions 970a and 970b.

  In this embodiment, in step S3, the extraction region setting unit 223 has two extraction regions 970a at different positions (left and right in the drawing) at different depths on the scan plane 920, for example, as shown in FIG. 970b can also be set.

  For example, in the case of the two extraction regions 970a and 970b in FIG. 20, as shown in FIG. 21, when the gland duct of the extraction region 970a has a normal type I structure, a parallel sectional image of the extraction region 970a. The pit pattern of the linear cavity region 980 indicated by the color parallel cross-sectional image 990a obtained by editing the color tone is a regular array having a substantially circular shape. On the other hand, for example, when the gland duct of the extraction region 970b has an IV-type deformed structure, the pit pattern of the linear cavity region 980 indicated by the color parallel sectional image 990a obtained by editing the color tone of the parallel sectional image of the extraction region 970a is irregular. Shape and arrangement. The color parallel cross-sectional images 990a and 990b are examples in which the color tone is edited by the crystal violet color tone and the region 981 other than the linear cavity region 980 is set to a purple color tone.

  Subsequent to the processing in step S25, the processing unit 22 determines whether or not to set an enlarged region on the parallel sectional image by a control signal from the operation control unit 32 via the I / F unit 229 (step S26).

  When determining that the enlarged region is set on the parallel sectional image, the processing unit 22 sets the enlarged region to be enlarged and displayed on the parallel sectional image by the enlarged region setting unit 237 (step S27). Specifically, as shown in FIG. 22, the enlargement area setting unit 237 adds an enlargement area 995 that is a two-dimensional area to the color parallel sectional image 990 in accordance with a setting signal from the operation control unit 32 via the I / F unit 229. Set.

  Then, the processing unit 22 generates, in the enlarged image generation unit 238, a color enlarged image 996 having the same tone as the color parallel cross-sectional image 990 obtained by enlarging the enlarged region 995 (step S28), as shown in FIG. The process ends.

  Here, the process of the lesion determination unit 235 in step S24 will be described.

  In lesions such as large intestine LST-NG, tumor / non-tumor, m cancer / sm cancer can be estimated with high accuracy using the pit pattern on the mucosal surface. It is difficult to identify.

  In step S24, the lesion determination unit 235, on the optical three-dimensional structure image, as shown in FIG. 23, the mucosal muscle plate 950 below the gland duct is cut off or cut off (missing). When the presence or absence of a lesioned part (region) is determined and it is determined that there is a lesioned part, the infiltration position of the sm cancer that is a lesioned part is specified and extracted as a lesioned region 997. Further, the lesion determination unit 235 generates a two-dimensional image 998 as shown in FIG. 24 in which the lesion region 997 in which the mucosal muscle plate 950 is interrupted is highlighted, and outputs it to the image composition unit 236.

  The image synthesizing unit 236 superimposes the two-dimensional image 998 on the color parallel cross-sectional image 990 of the pit pattern to synthesize the pit pattern abnormal state and the sm cancer infiltration position as shown in FIG. A composite image 999 that can be appropriately observed is generated.

  Note that the lesion area 997 in the two-dimensional image 998 is emphasized by, for example, displaying in another color different from the color tone of the color parallel cross-sectional image 990, changing the color density or saturation, or displaying a pattern such as diagonal lines. Is displayed. The image composition unit 236 can generate a composite image (not shown) in which the color parallel cross-sectional image 990 of the pit pattern and the extracted two-dimensional image 998 of the mucosal muscle plate are arranged.

  As described above, in the present embodiment, in addition to the effects of the first embodiment, by generating and observing a color parallel cross-sectional image to which a color map is applied from a horizontal slice image based on the flattened mucosal muscle plate 950, It is possible to observe in detail the gland duct structure in the vicinity of the mucosal muscularis in the lesioned part and the normal part where the mucous membrane is often thickened. Furthermore, this embodiment can identify the infiltration position of sm cancer in the mucosal muscle 950.

  Each embodiment described above can be applied to any organ in which the glandular structure appears on the mucosal surface, and can be applied to, for example, the stomach, duodenum, jejunum, ileum, colon, rectum, and the like.

  The optical structure observation apparatus and endoscope system of the present invention have been described in detail above, but the present invention is not limited to the above examples, and various improvements and modifications can be made without departing from the gist of the present invention. Of course you can go.

DESCRIPTION OF SYMBOLS 10 ... Image diagnostic apparatus, 22 ... Processing part, 100 ... Endoscope, 200 ... Endoscope processor, 220 ... Optical structure information detection part, 221 ... Glandular cavity extraction part, 222 ... Threshold storage part, 223 ... Extraction area setting 224... Area information calculation unit 225... Parallel tomographic image generation unit 226... Color map storage unit 227... Color tone editing unit 228. OCT processor, 500 ... monitor device

Claims (23)

The light of the measurement object obtained by scanning a scan plane composed of a first direction which is a depth direction of a measurement target having a mucosal layer and a second direction orthogonal to the first direction using low interference light. An optical structure that acquires a plurality of structure information while shifting the position along a third direction that is a direction substantially orthogonal to the scan plane, and constructs an optical three-dimensional structure image based on the acquired plurality of the optical structure information In the observation device,
A glandular cavity extracting means for extracting a glandular cavity of the mucosal layer by comparing an information value of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold;
An extraction region setting means for setting an extraction region having a parallel section as a plane in the mucosal layer;
Area information calculation means for performing a predetermined calculation on the optical structure information in the extraction area set by the extraction area setting means;
Parallel cross-section image generation means for generating a parallel cross-section image based on the calculation result of the area information calculation means;
Based on the glandular cavity extracted by the glandular cavity extracting means, a color tone editing means for editing the color tone of the parallel sectional image;
An optical structure observation apparatus comprising:   The optical structure observation apparatus according to claim 1, wherein the color tone editing unit edits the color tone of the parallel sectional image based on a preset color map.   The optical structure observation apparatus according to claim 2, wherein the color map specifies a color tone of at least one pigment of indigo carmine, crystal violet, and methylene blue.   The optical structure observation apparatus according to claim 2, further comprising a color tone switching unit that switches a color tone designated by the color map based on the predetermined threshold value.   5. The optical structure according to claim 4, wherein the color tone switching unit switches the color tone specified by the color map based on a plurality of sets of the predetermined threshold values according to a depth position of the plane in the mucous membrane layer. Observation device. The predetermined calculation executed by the region information calculation means is any of integration processing, maximum value projection processing, and minimum value projection processing in which the optical structure information in the extraction region is executed along a direction orthogonal to the plane. The optical structure observation apparatus according to claim 1, wherein the calculation is performed by one process. The extraction area setting means sets a plurality of extraction areas composed of different areas each having a plurality of parallel planes positioned at a plurality of desired heights parallel to the plane, each having a parallel cross section.
The area information calculation means performs the predetermined calculation for each of the plurality of extraction areas,
The optical structure observation device according to any one of claims 1 to 6, wherein the parallel section image generation unit generates a plurality of the parallel section images based on a calculation result for each of the plurality of extraction regions. . The optical structure observation apparatus according to claim 7, further comprising an image synthesis unit that generates a synthesized image obtained by synthesizing the plurality of parallel cross-sectional images. Two-dimensional area designating means for designating an arbitrary two-dimensional area on the parallel sectional image;
Image enlarging means for generating an enlarged image obtained by enlarging the image of the two-dimensional region;
The optical structure observation apparatus according to claim 1, further comprising: A reference layer extracting means for extracting at least a mucosal muscle plate of the mucosal layer as a reference layer from the optical structure information constituting the optical three-dimensional structure image;
A reference layer flattening means for flattening the reference layer;
A structure image converting means for reconstructing the light three-dimensional structure image as the flattened reference layer and generating a three-dimensional converted light structure image;
Further comprising
The extraction region setting means sets an extraction region having a plane located at a desired depth in the mucosal layer parallel to the reference layer as the parallel section on the three-dimensional converted light structure image. The optical structure observation apparatus according to any one of claims 1 to 9. A mucosal muscularis lesion determining means for determining the presence or absence of a lesioned part of the mucosal muscle and extracting a lesion area when the lesion is present;
A lesion region superimposing unit that generates a region image of the lesion region and superimposes the region image on the parallel slice image;
The optical structure observation apparatus according to claim 10, further comprising: The light of the measurement object obtained by scanning a scan plane composed of a first direction which is a depth direction of a measurement target having a mucosal layer and a second direction orthogonal to the first direction using low interference light. An optical structure that acquires a plurality of structure information while shifting the position along a third direction that is a direction substantially orthogonal to the scan plane, and constructs an optical three-dimensional structure image based on the acquired plurality of the optical structure information In the structure information processing method of the observation device,
A glandular cavity extraction step of extracting the glandular cavity of the mucosal layer by comparing the information value of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold;
An extraction region setting step for setting an extraction region having a parallel section as a plane in the mucosa layer;
A region information calculation step for performing a predetermined calculation on the optical structure information in the extraction region set in the extraction region setting step;
A parallel slice image generating step for generating a parallel slice image based on the calculation result of the region information calculation step;
Based on the glandular cavity extracted in the glandular cavity extraction step, a color tone editing step for editing the color tone of the parallel sectional image;
A structure information processing method for an optical structure observation apparatus.   13. The structure information processing method for an optical structure observation apparatus according to claim 12, wherein the color tone editing step edits a color tone of the parallel sectional image based on a preset color map.   The structure information processing method of the optical structure observation apparatus according to claim 13, wherein the color map specifies a color tone of at least one pigment of indigo carmine, crystal violet, and methylene blue.   15. The structure information processing method for an optical structure observation apparatus according to claim 13, further comprising a color tone switching step of switching a color tone designated by the color map based on the predetermined threshold value.   16. The optical structure according to claim 15, wherein the color tone switching step switches the color tone specified by the color map based on a plurality of sets of the predetermined threshold values corresponding to depth positions of the plane in the mucosa layer. Structure information processing method of observation device. The predetermined calculation executed by the region information calculation step is any of integration processing, maximum value projection processing, and minimum value projection processing in which the optical structure information in the extraction region is executed along a direction orthogonal to the plane. The structure information processing method of the optical structure observation apparatus according to any one of claims 12 to 16, wherein the calculation is performed by one process. The extraction region setting step sets a plurality of extraction regions composed of different regions each having a plurality of parallel surfaces located at a plurality of desired heights parallel to the plane, each having a parallel cross section.
The region information calculation step performs the predetermined calculation for each of the plurality of extraction regions,
The optical structure observation device according to any one of claims 12 to 17, wherein the parallel slice image generation step generates a plurality of the parallel slice images based on a calculation result for each of the plurality of extraction regions. Structure information processing method. The structure information processing method of the optical structure observation apparatus according to claim 18, further comprising an image composition step of generating a composite image obtained by combining the plurality of parallel cross-sectional images. A two-dimensional region designating step for designating an arbitrary two-dimensional region on the parallel sectional image;
An image enlargement step for generating an enlarged image obtained by enlarging the image of the two-dimensional region;
The structural information processing method for an optical structure observation apparatus according to claim 12, further comprising: A reference layer extraction step for extracting at least a mucosal muscle plate of the mucosa layer as a reference layer from the optical structure information constituting the optical three-dimensional structure image;
A reference layer planarization step for planarizing the reference layer;
A structural image conversion step for reconstructing the optical three-dimensional structure image as the flattened reference layer and generating a three-dimensional converted optical structure image;
Further comprising
The extraction region setting step sets an extraction region having a plane located at a desired depth in the mucosal layer parallel to the reference layer as the parallel section on the three-dimensional converted light structure image. The structure information processing method of the optical structure observation apparatus according to any one of claims 12 to 20. Determining the presence or absence of a lesioned portion of the mucosal muscle plate, and extracting the lesion area when the lesioned portion is present;
A lesion region superimposing step of generating a region image of the lesion region and superimposing the region image on the parallel slice image;
The structure information processing method for an optical structure observation apparatus according to claim 21, further comprising: A scan comprising a first light source that emits low interference light, a first direction that is a depth direction of a measurement target having a mucosal layer using the low interference light, and a second direction orthogonal to the first direction. An optical probe that acquires a plurality of optical structure information of the measurement object obtained by scanning a surface while shifting a position along a third direction that is a direction substantially orthogonal to the scan surface; and the plurality of acquired lights An optical structure observation apparatus having an optical structure information processing apparatus for constructing an optical three-dimensional structure image based on the structure information;
An endoscope having a second light source that emits illumination light, and a treatment instrument channel that has an imaging unit that images the measurement object using the illumination light at the distal end of the insertion portion, and the optical probe is inserted into the insertion portion. An endoscope device comprising an endoscope processor that generates an endoscope image by performing signal processing on an imaging signal from the imaging means;
In an endoscope system comprising:
The optical structure observation apparatus is
A glandular cavity extracting means for extracting a glandular cavity of the mucosal layer by comparing an information value of the optical structure information constituting the optical three-dimensional structure image with a predetermined threshold;
An extraction region setting means for setting an extraction region having a parallel section as a plane in the mucosal layer;
Area information calculation means for performing a predetermined calculation on the optical structure information in the extraction area set by the extraction area setting means;
Parallel cross-section image generation means for generating a parallel cross-section image based on the calculation result of the area information calculation means;
Based on the glandular cavity extracted by the glandular cavity extracting means, a color tone editing means for editing the color tone of the parallel sectional image;
An endoscope system comprising: