Image processing device, image processing method, and program

Abstract

To provide a mechanism to acquire a front image including information expanding in a plurality of depth regions in an eye to be examined and detailed information on each depth region.SOLUTION: An image processing device includes: acquisition means for acquiring three-dimensional data on an eye to be examined; region division means for executing processing to divide the three-dimensional data into a plurality of depth regions in a depth direction of the eye to be examined; region selection means for selecting at least two depth regions of the plurality of depth regions; front image generation means for generating a front image for each depth region by executing appropriate projection processing for each of the at least two depth regions; and composite front image generation means for generating a unicolor composite front image by executing processing for compositing the front image generated for each depth region.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an image processing device and an image processing method for processing an image related to an eye to be examined, and a program for causing a computer to function as the image processing device. [Background technology]

[0002] In recent years, OCT Angiography (OCTA), based on OCT (Optical Coherence Tomography) technology, has been proposed as a method of acquiring images of the examined eye in ophthalmic treatment, as an angiography method that does not use contrast agents. In this OCTA, it is common to generate and display a two-dimensional anterior image of blood vessels (hereinafter referred to as "OCTA anterior image") by projecting and displaying three-dimensional OCT motion contrast data acquired by OCT onto a two-dimensional plane perpendicular to the depth direction.

[0003] A method for acquiring an image of a subject's eye using OCTA is described in Patent Document 1. In Patent Document 1, a segmentation process is performed to segment the acquired 3D OCT motion contrast data into a plurality of depth regions, and an OCTA front image is generated and displayed from the 3D OCT motion contrast data in a specific depth region from among the segmented depth regions. In this way, Patent Document 1 allows the quality of the acquired 3D OCT motion contrast data to be confirmed from the displayed OCTA front image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-6179 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology of Patent Document 1, since an OCTA front image of one depth region selected from multiple depth regions is generated and displayed, only information of the one depth region (here, blood vessel information) in the subject's eye can be confirmed. In other words, in the technology of Patent Document 1, comprehensive information covering multiple depth regions in the subject's eye cannot be obtained.

[0006] On the other hand, in an OCTA front image generated by simply projecting all depth regions using a single projection method, detailed information about the subject's eye (here, vascular information) may not be obtained depending on the depth region.

[0007] The present invention has been made in consideration of such problems, and aims to provide a mechanism for acquiring a synthetic front image in which detailed information about each depth region can be observed in a single image in at least two depth regions of a plurality of depth regions of a test eye. In addition to the above-mentioned objectives, the achievement of actions and effects derived from each configuration shown in the embodiments of the present invention described below, which cannot be obtained by conventional techniques, can be positioned as another objective of the present application. [Means for solving the problem]

[0008] An image processing device according to an embodiment of the present invention is an image processing device characterized by having an acquisition means for acquiring three-dimensional data of a test eye, a region division means for performing processing to divide the three-dimensional data into a plurality of depth regions in the depth direction of the test eye, a region selection means for selecting at least two depth regions from the plurality of depth regions, a front image generation means for performing an appropriate projection processing on each of the at least two depth regions to generate a front image for each of the depth regions, and a composite front image generation means for performing processing to combine the front images generated for each of the depth regions to generate a single-color composite front image. In addition, an image processing method according to an embodiment of the present invention is an image processing method characterized by having an acquisition step of acquiring three-dimensional data of a test eye, a region division step of performing processing to divide the three-dimensional data into a plurality of depth regions in the depth direction of the test eye, a selection step of selecting at least two depth regions from the plurality of depth regions, a front image generation step of performing an appropriate projection processing on each of the at least two depth regions to generate a front image for each of the depth regions, and a composite front image generation step of performing processing to combine the front images generated for each of the depth regions to generate a composite front image. Effect of the Invention

[0009] According to the present invention, it is possible to acquire a front image that comprehensively includes information covering a plurality of depth regions in the subject's eye and also enables detailed information of each depth region to be observed. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of a schematic configuration of an ophthalmic examination system according to a first embodiment of the present invention. [Diagram 2] 1 is a diagram illustrating an example of a functional configuration of an ophthalmologic image processing apparatus according to a first embodiment of the present invention. [Diagram 3] 5 is a flowchart showing an example of a processing procedure of an ophthalmological image processing method performed by the ophthalmological image processing apparatus according to the first embodiment of the present invention. [Figure 4] 4 is a diagram showing an example of an OCTA front image for each depth region generated in step S308 in FIG. 3 and a synthetic OCTA front image generated in step S309 in FIG. 3. FIG. [Diagram 5] FIG. 13 illustrates the first embodiment of the present invention and shows an example in which a synthetic OCTA front image is displayed on an examination confirmation screen that accepts an instruction to reacquire three-dimensional OCT data. [Figure 6] 10 is a flowchart showing an example of a processing procedure of a report creation processing method by an ophthalmologic image processing apparatus according to a second embodiment of the present invention. [Figure 7]FIG. 7 is a diagram showing an example of an examination report screen displayed on the display means by the display control means in the report display step S705 in FIG. 6, the examination report screen including a synthetic OCT front image (synthetic OCTA front image in this example). [Figure 8] FIG. 11 shows a third modified example of the second embodiment of the present invention, and is a diagram showing an example of a follow-up screen regarding progress observation of a plurality of examinations including a synthetic OCT front image (synthetic OCTA front image), which is displayed on the display means by the display control means. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a mode (embodiment) for carrying out the present invention will be described with reference to the drawings. In the following description of the embodiment of the present invention, the same or equivalent components, members, and processes shown in each drawing will be given the same reference numerals, and duplicated descriptions will be omitted as appropriate. In addition, in each drawing, components, members, and processes that are not important for the explanation may be illustrated with some parts omitted.

[0012] (First embodiment) First, a first embodiment of the present invention will be described.

[0013] Fig. 1 is a diagram showing an example of a schematic configuration of an ophthalmic examination system 10 according to a first embodiment of the present invention. As shown in Fig. 1, the ophthalmic examination system 10 is configured to include an OCT imaging device 100, an ophthalmic image processing device 200, an operation means 300, a storage means 400, and a display means 500. In the example shown in Fig. 1, the ophthalmic examination system 10 is a system that examines an eye E to be examined (more specifically, a fundus Ef of the eye E to be examined).

[0014] First, a brief description will be given of the OCT imaging device 100. The present invention mainly relates to a method for processing and displaying three-dimensional OCT data obtained by the OCT imaging device 100. Therefore, the OCT imaging device 100 is not limited to the device of this embodiment, but may be any OCT imaging device that can obtain three-dimensional OCT data, and various types and configurations are possible. The OCT imaging device 100 acquires an OCT tomographic image having depth information of a measurement range specified for the subject's eye E (for example, the surface of the fundus Ef of the subject's eye E) and an OCT interference signal for generating three-dimensional OCT data consisting of a plurality of OCT tomographic images. The OCT imaging device 100 is, for example, a Spectral-Domain OCT (SD-OCT). As shown in FIG. 1, the OCT imaging device 100 includes a light source 101, a half mirror 102, a galvanometer mirror 103, an objective lens 104, a reference mirror 105, a diffraction grating 106, and a line sensor 107.

[0015] In the OCT imaging device 100, low-coherence light emitted from a light source 101 is split into measurement light and reference light by a half mirror 102. The measurement light is incident on the subject's eye E (for example, the fundus Ef of the subject's eye E) via a galvanometer mirror 103 and an objective lens 104. The scanning position of the subject's eye E by the measurement light can be changed by moving the galvanometer mirror 103. The measurement light incident on the subject's eye E is reflected and scattered by the subject's eye E (for example, the fundus Ef of the subject's eye E), and then returns to the half mirror 102 by following a reverse optical path. On the other hand, the reference light is reflected and scattered by a reference mirror 105, and then returns to the half mirror 102 by following a reverse optical path. In the half mirror 102, the return light of the measurement light and the return light of the reference light are superimposed to generate interference light. The diffraction grating 106 separates the interference light generated by the half mirror 102 into wavelength components. The line sensor 107 detects the interference light dispersed by the diffraction grating 106 as wavelength components λ1 to λn corresponding to the pixels, and outputs an electrical signal corresponding to each wavelength component as an OCT interference signal.

[0016] The ophthalmic image processing device 200 is an image processing device, such as a personal computer, that processes images of the subject's eye E. In this ophthalmic image processing device 200, a built-in CPU (not shown) reads a program stored in a storage means 400 such as a hard disk into a built-in storage unit (not shown) and processes images of the subject's eye E. Note that, although an example in which the CPU built into the ophthalmic image processing device 200 performs processing has been described here, in the embodiment according to the present invention, a device that executes processing is not limited to a CPU, and may be, for example, a GPU or the like.

[0017] In this embodiment, the ophthalmologic image processing device 200 may be a personal computer, and may be configured to include, for example, an operation means 300 for inputting information, which is configured with a keyboard and a mouse, a storage means 400 such as a hard disk, and a display means 500 such as an LCD display for displaying various information and various image data. The display means 500 functions as a user interface for receiving instructions from an operator together with the operation means 300, and the storage means 400 stores various information (including programs) and various image data, and also stores various information and various image data obtained by processing the ophthalmologic image processing device 200. Based on information input from the operation means 300, the display means 500 realizes functions such as processing image data taken from the storage means 400 and generating a display screen of the display means 500, and also controls the operation of the OCT imaging device 100.

[0018] The above-described ophthalmic image processing device 200 and OCT imaging device 100 work together to function as an ophthalmic examination system 10 for examining the subject's eye E. The ophthalmic image processing device 200 is communicatively connected to the OCT imaging device 100 by wired or wireless communication means, but does not need to be communicatively connected to the OCT imaging device 100 at all times, as long as it is communicatively connectable. Of course, the ophthalmic image processing device 200 and the OCT imaging device 100 do not need to be separate devices as shown in FIG. 1, and for example, the OCT imaging device 100 may have the functions of the ophthalmic image processing device 200.

[0019] 1, the display means 500 and the operation means 300 are configured separately, but they may be configured as an integrated unit such as a touch panel. The ophthalmologic image-processing device 200 may be a smartphone or a tablet terminal in which the operation means 300, the storage means 400, and the display means 500 are integrated.

[0020] Fig. 2 is a diagram showing an example of a functional configuration of an ophthalmologic image processing apparatus 200 according to the first embodiment of the present invention. In Fig. 2, the same components as those shown in Fig. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0021] The ophthalmologic image processing device 200 has an OCT imaging device control means 211, an OCT data acquisition means 212, an image processing means 213, and a display control means 214, all of which are shown in Fig. 2, by executing a program stored in a built-in storage means 400 by a CPU (not shown) built into the ophthalmologic image processing device main body 210. Here, the image processing means 213 also has functions of area division, OCT data area selection, projection processing allocation, OCT front image generation, and composite OCT front image generation, as will be described later.

[0022] The OCT imaging device control means 211 performs OCT imaging by controlling the OCT imaging device 100 based on operations of the operating means 300 by the examiner, the operator, and imaging conditions such as the scanning pattern and imaging range of the test eye E set using the operating means 300.

[0023] The photographing procedure and the image processing procedure according to the first embodiment will be described with reference to the flowchart of Fig. 3. Fig. 3 is a flowchart showing an example of the processing procedure of an ophthalmic image processing method by the ophthalmic image processing device 200 according to the first embodiment of the present invention. As described above, the procedure in Fig. 3 is performed by a CPU (not shown) built into the ophthalmic image processing device 200 executing a program stored in a storage unit (not shown) built into the ophthalmic image processing device 200.

[0024] First, in the first step S301, the ophthalmologic image-processing device 200 starts an imaging program based on, for example, an input from the operation means 300. For example, the display control means 214 causes the display means 500 to display a start-up screen, and the OCT imaging device control means 211 starts controlling the OCT imaging device 100 to prepare for startup. Then, when the startup preparation of the OCT imaging device 100 is completed, the process proceeds to the next step S302.

[0025] When the process proceeds to the patient selection step S302, the display control means 214 switches the display of the display means 500 from the start-up screen to a patient / examination selection screen. Here, the examiner uses the operation means 300 to select a patient, or, if it is a first visit, inputs patient information to specify the patient. For example, when the examiner inputs part of a patient's name in a patient input box, the display control means 214 searches for patients matching the input and displays them in a patient list on the display means 500. Then, when the examiner selects a patient from the displayed patient list, the ophthalmologic image-processing device 200 sets the selected patient as the examinee.

[0026] Next, in an imaging mode selection step S303, the examiner operates the operating means 300 to select an imaging mode for the next examination. The imaging modes include, for example, a Macula Disease imaging mode in which the macular region of the subject's eye E is imaged by a horizontal B-scan, a Glaucoma, Anterior imaging mode in which the macular region and the optic disc are imaged by a vertical B-scan, and an OCTA imaging mode. In this embodiment, the description will proceed assuming that the OCTA imaging mode is selected, but the OCT imaging device 100 of this embodiment stores an SLO image observed and imaged by a prepared SLO optical system (not shown) provided in the device as an observation optical system as a front image of the fundus together with three-dimensional OCT data of the fundus Ef of the subject's eye E.

[0027] Next, in a three-dimensional OCT data acquisition step S304, the OCT imaging device control means 211 starts preparation for imaging of the OCT imaging device 100 according to the imaging conditions previously determined as the imaging mode selected in step S303. Specifically, first, a fixation target projection unit (not shown) provided in the OCT imaging device 100 is controlled to project a fixation target at a predetermined position on the fundus Ef of the subject's eye. Next, an anterior segment observation camera (not shown) captures an image of the subject's eye E, and based on this, a drive unit (not shown) is controlled to start an auto-alignment operation of the OCT imaging device 100 with respect to the subject's eye E. When the alignment of the OCT imaging device 100 is completed, the OCT imaging device control means 211 controls the galvanometer mirror 103 to two-dimensionally scan the desired imaging range on the fundus Ef of the subject eye in the xy direction with the measurement light while sampling the output from the line sensor 107 in pixel units to obtain an OCT interference signal having reflection distribution information in the z direction at the scanning position within the imaging range. By obtaining this from each position in the imaging range and sequentially storing it in the storage means 400, it is possible to obtain an OCT interference signal that is the basis of three-dimensional OCT data. In this case, the OCT interference signal to be stored may be composed of multiple OCT interference signals, for example, at different times at the same position on the fundus Ef of the test eye E, obtained by repeatedly scanning the measurement range multiple times to calculate three-dimensional OCT motion contrast data. Although the method of generating the tomographic images can be realized by a known method and detailed description will be omitted, the image processing means 213 of the ophthalmologic image processing device 200 performs processes such as dispersion compensation processing, wavelength-to-wavenumber conversion, Fourier transformation, and fixed pattern noise removal processing on the acquired OCT interference signal to generate 3D OCT data that is a collection of tomographic images. The generated tomographic images may be stored in the storage means 400, or may be stored in another device by data communication via a network. Furthermore, when OCT motion contrast data is obtained as three-dimensional OCT data, a plurality of tomographic images, which are three-dimensional OCT data generated from at least two or more OCT interference signals that are different in time, are subjected to arithmetic processing such as alignment and decorrelation value calculation processing to obtain three-dimensional OCT motion contrast data. In addition, there are various methods for the arithmetic processing to obtain OCT motion contrast data, such as a method of calculating a phase difference of complex OCT data and a method of calculating a vector difference of complex OCT data, and any of these methods can be used. At this time, in order to segment the depth direction into a plurality of depth regions in the subsequent process, three-dimensional data may be generated by averaging a plurality of tomographic images at the same position generated to obtain OCT motion contrast data. As described above, in this embodiment, three-dimensional OCT data is acquired by processing, using the image processing means 213, the OCT interference signal received from the subject's eye using the OCT imaging device 100 in accordance with the procedure up to step S304, but acquisition of three-dimensional OCT data in the present invention also includes reading out and calculating a three-dimensional OCT interference signal already stored in the storage means 400, and simply reading in the three-dimensional OCT data stored in the storage means 400. Note that in the following steps, an explanation will be given taking as an example a case in which OCT motion contrast data is acquired as the three-dimensional OCT data.

[0028] Next, in the segmentation processing step S305, the image processing means 213 executes a segmentation process to segment the three-dimensional OCT motion contrast data acquired in S304 into a plurality of depth regions having a width in the depth direction of the subject's eye E. The target image of the segmentation process may be either a three-dimensional OCT tomographic image, which is three-dimensional OCT data generated from an OCT interference signal, or three-dimensional OCT motion contrast data. For example, a retinal layer boundary may be detected from each of the tomographic images constituting the three-dimensional data obtained by averaging a plurality of tomographic images at the same position generated to acquire the OCT motion contrast data, and the three-dimensional OCT motion contrast data may be segmented into a plurality of depth regions based on the detected retinal layer boundary. Alternatively, the segmentation may be based on the layer boundary of the OCT tomographic image detected using a trained model obtained by training a large number of data showing at least one retinal layer of the subject's eye E. Alternatively, instead of segmentation based on morphological information depicted as a tomographic image, a method of segmenting into a plurality of depth regions based on the distribution of blood vessels detected from three-dimensional OCT motion contrast data may be adopted. For example, in the case of segmenting into a plurality of depth regions based on the distribution of blood vessels, a method of first graphing a representative value (integrated value or average value of pixel values) of a pixel row in a direction intersecting the depth direction of the three-dimensional OCT motion contrast data of the subject's eye E, then obtaining a plurality of peaks in the graph of the representative value of the pixel row, and segmenting into a plurality of depth regions based on the plurality of peaks may be adopted. In this case, the plurality of depth regions may be segmented into three depth regions, for example, a region corresponding to the vitreous layer of the subject's eye E, a region corresponding to the retina layer, and a region corresponding to the choroid layer. In addition, the plurality of depth regions may be segmented into four depth regions by further segmenting the above-mentioned region corresponding to the retina layer into a region corresponding to the superficial layer and a region corresponding to the deep layer. Furthermore, it is possible to segment finer depth regions, for example, the region corresponding to the retinal layers described above, into a region corresponding to the optic nerve fiber layer, a region corresponding to the ganglion cell layer, a region corresponding to the inner plexiform and granular layers, and a region corresponding to the inner granular and outer plexiform layers. On the other hand, in the segmentation processing step S305, the retinal layer boundary and the vascular layer, which are the physical structures of the test site, may not be detected as described above, and the image may be segmented more simply by the coordinates in the depth direction. For example, the image processing means 213 may perform segmentation based on the frequency distribution of pixels having a predetermined pixel value or more. More specifically, the image may be segmented into a depth region higher than a predetermined threshold and a depth region lower than a predetermined threshold based on the frequency distribution of pixels having a predetermined pixel value or more. Also, for example, the image may be segmented into a plurality of depth regions based on the average pixel value in the depth direction of the test eye E in each depth region of the 3D OCT motion contrast data.

[0029] Next, in a data region selection step S306, the image processing means 213 selects at least two depth regions from among the multiple depth regions in the 3D OCT motion contrast data segmented in step S305. The at least two depth regions selected here are preferably depth regions with different characteristics. In this case, the depth regions with different characteristics are, for example, depth regions with different luminance values ​​(for example, average luminance values ​​for each depth region). When the motion contrast data is the subject, it should be noted that the average luminance corresponds to the average density of blood vessels and represents the difference in blood vessel structure. For example, there are no blood vessels in the vitreous layer of the subject's eye E, and there are radial peripapillary capillaries, a superficial capillary network, a middle capillary network, and a deep capillary network in the retinal layer of the subject's eye E. And there is a choroidal vascular layer (small and medium-sized blood vessels, large blood vessels) in the choroidal layer of the subject's eye E. A depth region to be observed can be selected from these depth regions with different vascular structures. Furthermore, it is preferable that the at least two depth regions are continuous (adjacent) regions. For example, although blood vessels do not exist in the vitreous layer of the subject's eye E, neovascularization may occur in diabetic retinopathy and the like. Therefore, when observing neovascularization in the vitreous layer, the image processing means 213 may select a plurality of continuous depth regions including the region corresponding to the vitreous layer. In this embodiment, for example, any of the region corresponding to the vitreous layer, the region corresponding to the retina layer, and the region corresponding to the choroid layer of the subject's eye E may be selected. Of course, this selection may be made by selecting a predetermined region, or may be automatically selected based on the characteristics of each region, or may be made so that the user can select and modify it as needed, or may be selected to include all regions in advance.

[0030] Next, in a projection processing allocation step S307, the image processing means 213 allocates an appropriate projection processing to the OCT motion contrast data of each of the at least two depth regions selected in the data region selection step S306. In this embodiment, the allocation of an appropriate projection processing is to determine an appropriate projection processing for generating an OCTA front image for each depth region selected in step S306. Here, in this embodiment, as long as an appropriate projection processing is allocated to each of the OCT motion contrast data of the at least two depth regions selected in the data region selection step S306, different projection processing may be allocated to each of the depth regions, or the same projection processing may be allocated. Specific examples of the projection processing to be allocated include average value projection method (AIP method), maximum value projection method (MIP method), minimum value projection method (MinIP method), median, variance, standard deviation, sum, etc. For example, if the average brightness value in the depth region selected in the data region selection step S306 is equal to or greater than a predetermined threshold, the projection processing by the AIP method may be allocated, and if it is less than the predetermined threshold, the projection processing by the MIP method may be allocated. Furthermore, for example, when the depth region selected by the image processing means 213 includes a region corresponding to the vitreous layer of the subject's eye E, a region corresponding to the retinal layer of the subject's eye E, and a region corresponding to the choroid layer of the subject's eye E, for example, projection processing by the MIP method may be assigned to the region corresponding to the vitreous layer and the region corresponding to the retinal layer of the subject's eye E, and projection processing by the AIP method may be assigned to the region corresponding to the choroid layer of the subject's eye E. The assignment of projection processing for each depth region may be set in advance, or may be set and changed on the spot by the examiner using an image display such as a tomographic image.

[0031] Next, the image processing means 213 executes the OCT front image generating step S308. The image processing means 213 performs the projection processing assigned in step S307 on each of at least two depth regions selected in the data region selecting step S306 to generate an OCT front image of the same single color for each depth region. Specifically, in this embodiment, the projection processing assigned in the projection processing assignment step S307 is performed on each of the OCT motion contrast data regions of at least two depth regions selected in the data region selecting step S306 to generate an OCT front image as a front image for each depth region. In this embodiment, an OCTA front image is generated as an OCT front image, which is a two-dimensional image obtained by projecting three-dimensional OCT motion contrast data onto a plane based on two reference planes in the depth direction (Z direction) of the subject's eye E.

[0032] Next, in a composite OCT front image generating step S309, the image processing means 213 performs a process of synthesizing the multiple OCTA front images generated for each depth region in step S308 to generate a composite OCT front image. In this embodiment, the image processing means 213 performs a process of synthesizing the OCTA motion contrast front images generated for each depth region in step S308 to generate a composite OCTA motion contrast front image. FIG. 4 is a diagram showing an example of the OCTA front image for each depth region generated in step S308 of FIG. 3 and the composite OCTA front image generated in step S309 of FIG.

[0033] 410 shown in Fig. 4(a) is an OCTA front image, which is an OCT front image of a depth region corresponding to the vitreous layer of the subject's eye E, generated by the MIP method in the OCT front image generating step S308, 420 shown in Fig. 4(b) is an OCTA front image, which is an OCT front image of a depth region corresponding to the retinal layer, generated by the MIP method, and 430 shown in Fig. 4(c) is an OCTA front image, which is an OCT front image of a region corresponding to the choroid layer, generated by the AIP method, and each is generated as a monochrome image (e.g., black and white image) of the same single color B / W. And 440 shown in Fig. 4(d) is a composite OCTA front image generated as a composite OCT front image by combining (additively combining here) the three OCTA front images corresponding to the above-mentioned depth regions, Fig. 4(a), (b), and (c).

[0034] Here, an additive synthesis process has been described as an example of a method for generating a synthetic OCTA front image (a method for generating a synthetic front image), i.e., a method for synthesizing a plurality of OCTA front images corresponding to each depth region, but the method is not limited to this, and weighted addition process, average value process, etc. may also be performed. In addition, image adjustments may be performed after synthesis, such as appropriate range adjustments and histogram adjustments as tone adjustments to adjust the tone of the image. Since the range that the display means can display is normally 8-bit color, it goes without saying that it is desirable to perform tone adjustments such as range adjustments and histogram adjustments when the display control means 214 prepares image data for display in the next image display step S310.

[0035] A specific example of the display method will be described below. In this embodiment, the 3D OCT motion contrast data is 32 bits or 16 bits, and the generated composite OCTA front image is also 32 bits or 16 bits. When the composite OCTA front image is displayed on an examination confirmation screen or the like, it is converted to 8 bits and displayed. In this case, it is desirable to generate a 32-bit or 16-bit OCTA front image for each depth region, synthesize these (additive synthesis here), and then convert the synthesized OCTA front image to 8 bits by adjusting the histogram. In this case, it is possible that the 8-bit range will be exceeded by additive synthesis, but processing is performed to keep pixels exceeding 8 bits within the 8-bit range. Alternatively, an OCTA front image for each depth region after conversion to 8 bits may be generated, and a 32-bit or 16-bit synthesized OCTA front image may be generated. Here, the synthesis process has been described as being applied to additive synthesis, but in this embodiment, it is not limited to this additive synthesis process, and weighted addition processing, average value processing, etc. may also be used.

[0036] Next, in step S310, the display control means 214 displays the synthetic OCTA front image generated in step S309 on the display means 500 as part of an inspection confirmation screen for confirming whether the 3D OCT data is good or bad (which may be a screen displaying a button to instruct the user to reacquire the 3D OCT data), or as part of an analysis screen for analyzing the 3D OCT data.

[0037] FIG. 5 illustrates the first embodiment of the present invention, and shows an example in which a synthetic OCTA front image is displayed on an examination confirmation screen 501 that accepts an instruction to reacquire three-dimensional OCT data.

[0038] In the display area 510, an SLO image captured during examination is displayed as a front image of the subject's eye E. Of course, the front image of the subject's eye E displayed here is not limited to an SLO image. For example, it may be a front image composed of an OCT tomographic image, or a fundus image or fluorescent fundus image captured by a fundus camera.

[0039] In the display region 520, the synthetic OCTA en face image shown in FIG. 4(d) is displayed as the synthetic OCT en face image.

[0040] Display area 511 within display area 510 is provided so that the composite OCTA front image displayed in display area 520 is superimposed on the SLO image.

[0041] In the display region 530, OCT sectional images at positions indicated by indexes 523 and 513 superimposed on the display region 520 and the display region 511, respectively, are displayed. In the display region 540, OCT sectional images at positions indicated by indexes 522 and 512 are displayed. In the display region 550, OCT sectional images at positions indicated by indexes 524 and 514 are displayed.

[0042] In the display area 520 displaying the composite OCTA front image, the index 523 can be moved by the examiner operating the operating means 300, and a tomographic image at any position indicated by the index 523 is displayed in the display area 530. Here, the configuration is such that a tomographic image at any position indicated by the index 523 that can be moved by the examiner's operation is displayed, but a function may be added such that when the examination confirmation screen 501 is opened, the index 523 automatically transitions from the position of the index 522 to the position of the index 524 at regular intervals, and the OCT tomographic image displayed in the display area 530 is updated accordingly. On the examination confirmation screen 501 configured as described above, the examiner can instantly check whether the acquired 3D OCT data of the subject's eye E has been acquired correctly over the entire selected depth region, that is, whether the examination was successful, by looking at the displayed composite OCTA front image. Furthermore, if an area that requires confirmation, such as a finding, is found on the composite OCTA front image, it is possible to check the details of that area using the tomographic image displayed in the display area 530.

[0043] Here, the examiner decides whether to store the examination results or to re-photograph the subject's eye E based on the quality of the composite OCTA front image. The examination confirmation screen 501 is provided with an operation button 560 for accepting the decision, and the examiner operates one of the OK button 561 and the NG button 562 in the operation button 560. Based on the operation of this button, the success or failure (OK / NG) of the photographing result is stored in the storage means 400 together with the examination result including the composite OCTA front image, which is the composite OCT front image. At this time, if the examiner decides that the photographing result is inappropriate and operates the NG button 562, the state automatically transitions to a state where the same subject's eye E is photographed in the same photographing mode (re-photographing state). In this case, the composite OCTA front image and the examination results do not need to be stored in the storage means 400. When the above-described process of image display step S310 is completed, the process of the flowchart shown in FIG. 3 ends.

[0044] As described above, the ophthalmologic image processing apparatus 200 according to the first embodiment performs appropriate projection processing on each of the three-dimensional data of at least two depth regions among the acquired three-dimensional OCT data of the subject's eye E, and generates a front image in which detailed information (blood vessel information) of the at least two depth regions described above is appropriately depicted. This allows the blood vessel information of each depth region to be depicted more clearly by synthesizing the front images in which the blood vessel information of each depth region is depicted to generate a synthetic front image. At this time, since these front images are generated in a single, uniform color, the OCT motion contrast in each selected depth region is displayed in a naturally synthesized form, so that the examiner can naturally grasp the overall image of the OCT motion contrast over the entire selected depth region at once from one front image. This is particularly useful as an image that can significantly shorten the diagnosis time, since it allows the blood vessel structure and characteristics, as well as lesions in each region to be naturally grasped at once in a short time, in the case where continuous depth regions, for example, the entire retinal layer excluding the choroid, are continuously selected. By displaying such an image on the examination confirmation screen 501 to confirm the result of the examination, the examiner can instantly, efficiently, and stress-free confirm the result of the examination. Therefore, the ophthalmologic image processing device 200 according to the first embodiment can improve the diagnostic efficiency of a series of medical procedures by appropriately and usably displaying one composite OCTA front image generated in this way.

[0045] <Modification of the first embodiment> Next, a modified example of the first embodiment of the present invention will be described. In the following description, matters common to the first embodiment will be omitted, and only matters different from the first embodiment will be described.

[0046] In the first embodiment described above, in the segmentation processing step S305, the image processing means 213 divided (segmented) the three-dimensional OCT motion contrast data into multiple depth regions based on layer boundary information of the layers constituting the fundus Ef of the subject's eye E, but the present invention is not limited to this form, and this modified example adopts a mode in which the depth direction of the subject's eye E in the three-dimensional OCT motion contrast data is divided into multiple depth regions at a predetermined depth, for example, several tens of μm to several hundreds of μm.

[0047] In this case, a configuration may be adopted in which a predetermined depth to be segmented is set in advance, or a configuration may be adopted in which the examiner can arbitrarily set a depth to be a division for segmentation based on an OCT tomographic image or the like. When the examiner arbitrarily sets the depth, for example, a configuration in which the examiner sets the predetermined depth using a setting screen (not shown) may be adopted. In this case, the examiner can simultaneously check a composite OCTA front image obtained by combining OCTA front images of a plurality of depth regions desired by the examiner, and can directly check the vascular information represented in the composite OCTA front image, thereby making it possible to more clearly determine whether the segmentation in the depth direction specified by the examiner is appropriate.

[0048] Second embodiment Next, a second embodiment of the present invention will be described. In the following description of the second embodiment, matters common to the first embodiment will be omitted, and only matters different from the first embodiment will be described.

[0049] The schematic configurations of the ophthalmic examination system and ophthalmic image processing device according to the second embodiment are similar to the functional configurations of the ophthalmic examination system 10 according to the first embodiment shown in Figure 1 and the ophthalmic image processing device 200 according to the first embodiment shown in Figure 2, respectively.

[0050] FIG. 6 is a flowchart showing an example of a processing procedure of a report creation processing method by the ophthalmologic image-processing apparatus 200 according to the second embodiment of the present invention.

[0051] As in the patient selection step S302 in the first embodiment, after starting the imaging program in step S701 (which may include the selection of an imaging mode), in step S702, the display control means 214 controls the display means 500 to display a patient / examination selection screen. Then, when the examiner uses the operation means 300 to select a patient based on the patient / examination selection screen displayed on the display means 500, the ophthalmologic image-processing device 200 displays a list of past examinations of the selected patient, that is, examinations confirmed and saved on the examination confirmation screen 501 shown in FIG. 5 in the first embodiment. Here, the examiner may select a patient from the patient list displayed on the patient / examination selection screen, or may narrow down the search based on newly entered patient information on the patient / examination selection screen.

[0052] Next, in a previous examination selection step S703, the examiner uses the operation means 300 to select, for example, an examination for which 3D OCT motion contrast data was previously acquired from the examination list displayed on the display means 500. The examination may be selected by selecting a representative examination image to be analyzed, or a mode in which a plurality of examination images taken in the selected examination are analyzed collectively, rather than a single examination image to be analyzed, is also envisioned.

[0053] Next, in a report creation step S704, the image processing means 213 analyzes a specific image included in the selected examination to obtain the analysis results, and the display control means 214 forms a report screen for the examination based on the analysis results, the patient data, and the examination data.

[0054] Next, in step S705, the display control means 214 displays the report screen created in S704 on the screen of the display means 500, which is a report screen that displays the examination results of the three-dimensional OCT data.

[0055] FIG. 7 is a diagram showing an example of an examination report screen displayed on the display means 500 by the display control means 214 in the report display step S705 of FIG. 6, the examination report screen including a composite OCT front image (in this example, a composite OCTA front image).

[0056] 7(a), the display area 810 displays an SLO image, which is a front image of the subject's eye E, but the displayed front image of the subject's eye E is not limited to an SLO image. As the front image, for example, a front image composed of a tomographic image of the subject's eye E, a fundus image captured by a fundus camera, or a fluorescent fundus image can be used.

[0057] In the display area 820, a synthetic OCT front image expressed in a single color, grayscale, generated by using the processing from the 3D OCT data acquisition step S304 to the synthetic OCT front image generation step S309 in FIG. 3 in the first embodiment described above is displayed. At the same time, this synthetic OCT front image may be superimposed on the SLO image as shown as a synthetic OCT front image 811. Of course, the image displayed in the display area 820 is not limited to a synthetic OCTA front image. For example, two types of layer boundaries may be specified and an OCTA front image between the layer boundaries may be displayed in the display area 820, or the results of measuring them may be displayed as a map, or an analysis chart of a predetermined format may be superimposed and the average value of the measurement results in each sector prepared in the analysis chart may be displayed in a switchable manner. Furthermore, in this embodiment, when a synthetic OCTA front image is displayed in the display area 820, a control group 840 for selecting the configuration of the synthetic OCTA front image is provided below the display area 820. In the first column 841, layer names of depth regions prepared in advance in this embodiment and segmented are listed. The second column 842 provides check boxes that are switches for whether or not to synthesize each layer listed in the first column 841 into a synthetic OCTA en face image, and by turning the check boxes ON / OFF, it is possible to select whether or not to synthesize the layer. The third column 843 provides a pull-down menu for selecting a projection method for the layer, and the examiner can assign an appropriate projection method to each layer while checking the synthetic OCTA en face image displayed in the display area 820. The radio buttons in the fourth column 844 are controls used by the examiner to select a target layer when changing the layer boundary. More specifically, for example, when one of the two layer boundaries of the internal limiting membrane (ILM) and the ganglion cell (GCL) is specified as the layer boundary of Layer L2, only the Display check box of Layer L2 is turned ON, and MIP is selected in the Projection pull-down menu, the OCTA en face image displayed in the display area 820 is a single-layer (i.e., unsynthesized) en face image in which the OCT motion contrast between the ILM layer and the GCL layer is projected by the MIP method.Here, for example, if the display check boxes for layers L2, L3, and L4 are ON as shown in Fig. 7(a), the OCTA front image displayed in the display area 820 is a composite of layers L2, L3, and L4. Also, for example, if the Border radio button 844 for layer L2 is ON as shown in Fig. 7(a), the layer boundaries of the internal limiting membrane (ILM) and ganglion cell layer (GCL) are superimposed on the representative tomographic image shown in the display area 830, and can be finely adjusted in the vertical direction by dragging them. Furthermore, the shape of the layer boundaries may be changed by individually adjusting the controls displayed on the layer boundaries. In this way, the examiner can generate synthetic OCTA front images in various formats by operating the control group 840 that selects the composition of the synthetic OCTA front image. Although the control group 840 has been described as being constantly displayed on the screen, it may of course be possible to set this on a separate setting screen, and furthermore, it may be possible to configure a configuration in which an OCTA front image of one depth region and an OCT luminance front image or map display of various measurement results can be switched between, and to configure a separate setting screen for switching together. This allows the examiner to check the examination results from various angles, enabling a better diagnosis.

[0058] As described above, the display area 811 within the display area 810 displays the synthetic OCT front image displayed in the display area 820 so as to be superimposed on the SLO image, but may also be changed in conjunction with the synthetic OCT front image being changed in the above-mentioned procedure.

[0059] As described above, the examiner confirms the examination results while switching the display form of the report screen, and then closes the report screen, thereby completing the processing of the flowchart shown in Fig. 6. In this way, the second embodiment of the present invention makes it possible to timely switch the selection for each depth region, and to generate and display a composite OCTA front image that allows a clearer understanding of vascular information by switching and selecting an appropriate projection process. This makes it possible to improve the diagnostic efficiency of the subject's eye E.

[0060] <Modification 1 of the second embodiment> Next, a first modified example of the second embodiment of the present invention will be described. In this first modified example, in the OCT front image generating step S308 in FIG. 3, not only is it possible to generate an OCTA front image of the same single color for each depth region as in the first embodiment, but it is also possible to assign (allocate) different color information (RGB) to each of the depth regions. Then, in the composite OCT front image generating step S309 in the first embodiment, it is possible to generate two types of composite OCT front images by selecting either a first synthesis process for synthesizing OCT front images of the same single color or a second synthesis process for synthesizing OCT front images having different color information for each depth region. The processing steps for generating a composite OCT front image are substantially similar to those in the first embodiment described above, so an example of the method will be described below with reference to FIG. 3.

[0061] 3, the image processing means 213 synthesizes each layer of the vitreous body, retina, and choroid segmented in the segmentation processing step S305 as at least two continuous depth regions, and selects an area L1 corresponding to the vitreous layer, an area L2 corresponding to the retinal layer, and an area L3 corresponding to the choroid layer of the subject's eye E. In addition, in the projection processing allocation step S307, as an initial setting, the projection processing by the MIP method is allocated to the area L1 corresponding to the vitreous layer and the area L2 corresponding to the retinal layer of the subject's eye E, and the projection processing by the AIP method is allocated to the area L3 corresponding to the choroid layer.

[0062] Then, in the subsequent OCT front image generating step S308, a blue (B) component is assigned to the region L1 corresponding to the vitreous layer selected as the region in the depth direction, a green (G) component is assigned to the depth region L2 corresponding to the retina layer, and a red (R) component is assigned to the region corresponding to the choroid layer as the initial setting of the color information. Of course, since the first object of the present invention is to generate a synthetic OCT front image of a single color, it is recommended not to assign colors as the initial value setting, but in order to simplify the explanation, an example in which colors are assigned as the initial setting is taken up. Of course, it goes without saying that it is desirable to prepare this initial setting so that it can be changed on an initial setting screen prepared separately. As an actual OCT front image generation, the image processing means 213 generates an OCTA front image by performing a projection process by the MIP method on the OCT motion contrast data for the region L2 corresponding to the retinal layer, and sets this to the green (G) component of a 24-bit color image. At this time, if the luminance value of the OCTA front image exceeds 8 bits, processing is performed so that it falls within the 8-bit range. In addition, the red (R) component and the blue (B) component are set to be empty. By the above process, the OCTA front image of the region L2 corresponding to the retinal layer is generated as a front image expressed in gradation of only the green (G) component. Note that, when the luminance value is set to the green component, the luminance value may be inverted to set the color component. This makes it possible to invert the gradation. Note that, without being limited to a configuration in which one color component is assigned, a configuration in which two color components are assigned may be used, or more generally, color components may be combined to fix a specific hue. For example, the retinal layer may be expressed in gradation of yellow by setting the same value to the red component and the green component. In this way, the image processing means 213 generates an OCTA front image having different color information for each depth region. Note that color information obtained by inverting the luminance value of the OCTA motion contrast front image of a specific depth region may be added. For example, when the choroid layer of the subject's eye E is displayed in grayscale in the OCTA motion contrast front image, blood vessel information may be displayed in black (low signal = small pixel value). For this reason, by inverting the luminance value of the OCTA motion contrast front image to create a color image, it is possible to obtain the same visibility as blood vessel information in other depth regions.

[0063] Then, in the composite OCT front image generating step S309, the image processing means 213 generates a composite OCTA front image by combining the OCTA front images to which different color information is assigned for each depth region. In this embodiment, additive combining processing is used as the combining processing. By following the above processing procedure, the image processing means 213 can generate a composite OCTA front image in which the characteristics of each depth region are expressed by each color information. In addition, for example, the image processing means 213 may adjust brightness, contrast, and histogram as tone adjustment for the generated composite OCTA front image. Note that similar adjustments may also be performed on each OCTA front image before the combining processing is performed. FIG. 7(b) is an example of an examination report screen generated by the above-mentioned procedure. In FIG. 7(b), a color allocation pull-down menu 851 capable of changing the allocated color is added to the control group 840 for selecting the composition of the composite OCTA front image on the examination report screen of FIG. 7(a). At the start of displaying the examination report screen, parameters for generating a composite OCTA front image are set for both controls according to their initial values. That is, in the B / W and Color allocation display switching radio button 850 shown in FIG. 7(b), Color is selected, and the MIP method is assigned as the projection method and the blue (B) component is assigned as the color information to the region L1 corresponding to the vitreous layer, which is the selected depth region, the MIP method and the green (G) component are assigned to the region L2 corresponding to the retina layer, and the AIP method and the red (R) component are assigned to the region L3 corresponding to the choroid layer.

[0064] As described above, the examination report screen is first displayed according to the initial settings, so that the information of each selected depth region of the composite OCTA front image is displayed with appropriate projection processing and different color tones in the display area 820. By observing this composite OCTA front image plane, the examiner can clearly recognize the information of each depth region, i.e., blood vessel information, in a manner that makes it possible to distinguish them based on the different color tones. On the other hand, in this synthetic OCTA front image plane, blood vessels near the boundaries of depth regions are discontinuously displayed in different colors, making it difficult to correctly grasp blood vessel information of multiple continuous regions in a unified manner. Therefore, in this modification 1, the method of generating a synthetic OCTA front image is prepared so that it can be switched depending on the diagnostic purpose. In other words, when the examiner switches the B / W and Color allocation display switching radio button 850 from Color to B / W, the projection method of each area remains the same, but the color allocation switches to B / W, which is a single, unambiguous color, and the composite OCTA front image displayed in the display area 820 switches to a B / W surface image composited in a single, uniform color, as shown in the second embodiment. Furthermore, for another diagnostic purpose, the examiner can operate the pull-down menu 851 for the region L3 corresponding to the choroid layer to select B and reassign the color assignment to the blue component. In response to this operation, the radio button 850 for switching between B / W and Color assignment display is changed back to Color, and a composite OCTA front image is displayed in which only the blood vessel information in the region L3 corresponding to the choroid layer is displayed in blue and the other regions remain in B / W. In this manner, in this first modified example, it is possible to display various composite OCTA front images generated with different parameters.

[0065] In the above, an example has been described in which a 24-bit color image format is adopted for the composite OCTA front image obtained by combining three regions of the vitreous layer, retina layer, and choroid layer of the subject's eye E as each depth region, and the image is displayed by switching between the same monochrome color B / W and a composite image of three colors RGB. However, it goes without saying that the method of selecting the depth region, the number of regions, and the image format are not limited to this. For example, the image may be converted to a 32-bit color image. A 32-bit color image is a color image in which the transparency component (α component) can be set in 256 steps in addition to the red component, green component, and blue component in a 24-bit color image. By converting to a 32-bit color image, it becomes possible to set the transparency for each pixel. This makes it possible to add transparency to color information, and in a composite OCTA front image generated by combining OCTA front images, it is possible to lower the transparency of the part to be emphasized (for example, blood vessel information) and increase the transparency of the opposite part. This makes it easier for the examiner to visually recognize the blood vessel information. Of course, the number of bits is not limited to these, and the image may be converted to a color image of any number of bits. For example, it may be configured to convert to a 48-bit color image. In the case of a 48-bit color image, the red, green, and blue components can each be expressed in 16 bits, and by converting the luminance value of the OCTA front image in each depth region to 16 bits, it becomes unnecessary to perform processing to fit it into 8 bits.

[0066] In addition, in the present modified example 1, the color information is assigned to the OCTA front image generated by performing the projection process appropriately for each depth region, and then the synthesis process is performed to generate the synthetic OCTA front image, but this is not limited to the above. For example, the OCT front image may be generated by directly assigning color information to the 3D OCT motion contrast data acquired in the 3D OCT data acquisition step S304 according to the region information selected in the data region selection step S306. Note that, in the above embodiment and modified examples, an example is described in which the synthetic front image is generated from the 3D OCT motion contrast data, but it goes without saying that it may be generated from the 3D OCT luminance data.

[0067] <Modification 2 of the second embodiment> In the above-described second embodiment, an example of displaying a report of an examination including a composite OCTA front image, which is a composite OCT front image, is shown, but the present invention is not limited to this. For example, a configuration may be used in which a plurality of OCTA front images are displayed. More specifically, a configuration may be used in which a composite OCTA front image and an OCTA front image before synthesis are simultaneously displayed in one report from three-dimensional OCT data of the subject's eye E included in the result of one examination.

[0068] <Modification 3 of the second embodiment> In the above-described second embodiment, an example is shown in which a report screen related to one examination including a composite OCTA front image, which is a generated composite OCT front image, is displayed, but the present invention is not limited to this. For example, a configuration may be used in which a composite OCTA front image related to each of a plurality of examinations is displayed on a follow-up screen related to progress observation of the examination results of the subject's eye.

[0069] FIG. 8 shows a third modified example of the second embodiment of the present invention, and is a diagram showing an example of a follow-up screen 901 regarding progress observation of multiple examinations including a synthetic OCT front image (synthetic OCTA front image) displayed on the display means 500 by the display control means 214.

[0070] A follow-up screen 901 shown in Fig. 8 is, for example, a screen for analyzing three-dimensional OCT data of the subject's eye E. Specifically, the follow-up screen 901 shown in Fig. 8 is a follow-up screen for comparing three-dimensional OCT data of the subject's eye E acquired at a certain date and time with three-dimensional OCT data of the subject's eye E acquired at a date and time different from the date and time at which the three-dimensional OCT data was acquired.

[0071] In the follow-up screen 901 shown in FIG. 8, a display area 910 displays, for example, a composite OCTA en face image of the examination selected in step S703 in FIG. 6 (hereinafter, referred to as the "base examination").

[0072] In the follow-up screen 901 shown in FIG. 8, a maximum of three examinations (examination 921, examination 922, and examination 923) of the same subject eye E performed before the base examination are displayed in the display area 920. Also, the examinations 921, 922, and 923 shown in FIG. 8 each include a composite OCTA front image. The examinations displayed in the display area 920 may be the three examinations immediately preceding the base examination, or may be three examinations selected from past examinations so that the examination dates are equally spaced. Also, if there is no examination or the number of examinations is less than three, only the past examinations that can be displayed may be displayed. Note that the number of examinations displayed on the follow-up screen 901 shown in FIG. 8 is not limited to four examinations including the base examination, and may be, for example, five or more examinations or three examinations.

[0073] The images displayed in the display area 910 and the display area 920 may be a composite OCTA front image or an OCTA front image. The composite OCTA front image and the OCTA front image may be different for each examination. Each examination may be switched between the composite OCTA front image and the OCTA front image. The composite OCTA front image or the OCTA image to be displayed may be linked. For example, when the image displayed in the display area 910 is switched from the composite OCTA front image to the OCTA front image, the composite OCTA front image of each examination displayed in the display area 920 is also switched to the OCTA front image and updated. The linked display is not limited to the display of the composite OCTA front image and the OCTA front image. For example, the magnification ratio of the composite OCTA front image or the OCTA front image, and various analysis results superimposed on the composite OCTA front image or the OCTA front image may also be linked. Also, they do not have to be updated linked. This allows the examiner to change the display method of a specific image that he or she particularly wants to focus on after comparing the results of each examination. In addition, whether the display contents of the OCTA front image (switching between composite OCTA front image / OCTA front image, magnification ratio, analysis result) are linked may be switched by arranging a check box not shown. Alternatively, a configuration may be used in which the composite OCTA front image is displayed on a right / left eye report screen that allows comparison of the test results of both eyes. For example, the test displayed on the right / left eye report screen displays a base test and a test result (comparison test) of an eye on the side different from the base test performed on the same day as the base test, and the comparison test includes an OCTA image. The OCTA front image displayed on the right / left eye report screen may be a composite OCTA front image or an OCTA front image, as in the follow-up screen. In addition, the display contents of the composite OCTA front image or the OCTA front image may be linked in the same way, or a check box may be arranged to switch the link. In addition, when the composite OCT motion contrast front image or the OCTA front image on the right / left eye report screen are linked, the display contents are linked in consideration of left / right symmetry.

[0074] With the above configuration, a composite OCTA front image of multiple tests is displayed on the follow-up screen 901 of the display means 500, allowing the examiner to check multiple tests at once, thereby improving the diagnostic efficiency of the test eye E.

[0075] <Modification 4 of the second embodiment> In the above-mentioned first and second embodiments, an example is shown in which an OCTA image, which is an OCT front image, is synthesized to generate and display a synthetic OCTA front image, which is a synthetic OCT front image, but the present invention is not limited to this. For example, three-dimensional OCT intensity data (three-dimensional OCT luminance data) indicating the intensity of the OCT signal of the subject's eye E is acquired as three-dimensional data, and a luminance En-Face image for each layer is generated as an OCT intensity front image (OCT luminance front image) from the three-dimensional OCT data, and the luminance En-Face image for each layer may also be synthesized in the same manner to generate a full-layer synthetic luminance En-Face image as a synthetic OCT front image.

[0076] The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions. This program and a computer-readable storage medium storing the program are included in the present invention.

[0077] It should be noted that the above-mentioned embodiments of the present invention are merely illustrative examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted as being limited by these. In other words, the present invention can be implemented in various forms without departing from its technical concept or main features.

[0078] The disclosure of the embodiments of the present invention includes the following configurations, methods, and programs. [Configuration 1] An acquisition means for acquiring three-dimensional data of a subject's eye; an area dividing means for dividing the three-dimensional data into a plurality of depth areas in a depth direction of the subject's eye; A region selection means for selecting at least two depth regions from the plurality of depth regions; a front image generating means for performing an appropriate projection process on each of the at least two depth regions to generate a front image for each of the depth regions; a composite front image generating means for performing a process of synthesizing the front images generated for each depth region to generate a single-color composite front image; 13. An image processing device comprising: [Configuration 2] further comprising an allocation means for allocating the appropriate projection processing to each of the at least two depth regions; 2. The image processing device according to claim 1, wherein the front image generating means performs a projection process assigned by the assigning means for each of the depth regions to generate the front image for each of the depth regions. [Configuration 3] 3. The image processing device according to claim 2, wherein the allocating means allocates different projection processes to two depth regions of the at least two depth regions. [Configuration 4] 3. The image processing device according to configuration 2, wherein the allocating means allocates the same projection processing to two depth regions of the at least two depth regions. [Configuration 5] 5. The image processing device according to any one of configurations 1 to 4, wherein the single-color composite front image is a black and white image. [Configuration 6] The image processing device according to any one of configurations 1 to 5, wherein the synthetic front image generating means generates the synthetic front image by performing weighted addition processing on the front images generated for each depth region. [Configuration 7] 7. The image processing device according to any one of configurations 1 to 6, further comprising an image adjustment means for performing gradation adjustment on each of the front images generated for each of the depth regions. [Configuration 8] 8. The image processing device according to claim 7, further characterized in that the image adjustment means adjusts the luminance of the composite front image. [Configuration 9] 9. The image processing device according to any one of configurations 1 to 8, wherein the at least two depth regions selected by the region selection means are adjacent regions in a depth direction of the subject's eye. [Configuration 10] the region selection means selects one depth region from the plurality of depth regions; The image processing device according to any one of configurations 1 to 9, further comprising a display control means for switching between a front image of one depth region generated by the front image generation means by performing a projection process on the selected one depth region and the synthetic front image. [Configuration 11] 11. The image processing device according to any one of configurations 1 to 10, wherein the at least two depth regions are all of the plurality of depth regions. [Configuration 12] The image processing device according to any one of configurations 1 to 11, characterized in that the synthetic front image generation means is capable of generating a synthetic front image by combining the front images generated for each depth region by adding different color information to each of the front images. [Configuration 13] The at least two depth regions include a region corresponding to a vitreous layer of the test eye, a region corresponding to a retinal layer of the test eye, and a region corresponding to a choroid layer of the test eye, The image processing device according to configuration 2, wherein the allocating means allocates projection processing using the MIP method to the region corresponding to the vitreous layer and the region corresponding to the retinal layer, and allocates projection processing using the AIP method to the region corresponding to the choroid layer. [Configuration 14] the three-dimensional data is three-dimensional OCT motion contrast data obtained by processing a plurality of OCT signals at different times at the same position of the subject's eye; 14. The image processing device according to any one of configurations 1 to 13, wherein the front image is an OCT motion contrast front image based on the three-dimensional OCT motion contrast data. [Configuration 15] the three-dimensional data is three-dimensional OCT intensity data indicating an intensity of an OCT signal; 14. The image processing device according to any one of configurations 1 to 13, wherein the front image is an OCT intensity front image based on the three-dimensional OCT intensity data. [Configuration 16] The image processing device according to any one of configurations 1 to 15, characterized in that the region division means divides the depth direction of the fundus in the three-dimensional data into the multiple depth regions based on layer boundary information of layers constituting the fundus of the test eye. [Configuration 17] 16. The image processing device according to any one of configurations 1 to 15, wherein the region dividing means divides the three-dimensional data into the plurality of depth regions at a predetermined depth in a depth direction of the subject's eye. [Configuration 18] The image processing device according to any one of configurations 1 to 17, characterized in that the region selection means selects the at least two depth regions based on a frequency distribution of pixels having a predetermined pixel value or more in the three-dimensional data. [Configuration 19] The image processing device according to any one of configurations 1 to 17, characterized in that the region selection means selects the at least two depth regions based on an average pixel value in a direction intersecting a depth direction of the subject's eye in the three-dimensional data. [Configuration 20] 18. The image processing device according to any one of configurations 1 to 17, wherein the region selection means selects the at least two depth regions based on an average pixel value for each of the plurality of depth regions. [Configuration 21] The image processing device according to any one of configurations 1 to 20, further comprising a display control means for controlling the display of the composite front image on a screen for accepting an instruction to reacquire the three-dimensional data or on a screen for analyzing the three-dimensional data. [Configuration 22] The image processing device described in configuration 21, characterized in that the screen for analyzing the three-dimensional data is a screen for comparing the three-dimensional data with three-dimensional data of the test eye acquired at a date and time different from the date and time at which the three-dimensional data was acquired. [Configuration 23] A report generating means for generating a report of the inspection including the composite front image, 23. The image processing apparatus according to claim 21, wherein the display control means controls display of the report created by the report creation means on the screen. [Method 1] An acquisition step of acquiring three-dimensional data of a subject's eye; a region dividing step of dividing the three-dimensional data into a plurality of depth regions in a depth direction of the subject's eye; A selection step of selecting at least two depth regions from the plurality of depth regions; a front image generating step of performing an appropriate projection process on each of the at least two depth regions to generate a front image for each of the depth regions; a composite front image generating step of performing a process of synthesizing the front images generated for each depth region to generate a composite front image; 13. An image processing method comprising: [Program 1] A program for causing a computer to function as each of the means of the image processing device according to any one of configurations 1 to 23. [Explanation of symbols]

[0079] 10: ophthalmic examination system, 100: OCT imaging device, 101: light source, 102: half mirror, 103: galvanometer mirror, 104: objective lens, 105: reference mirror, 106: diffraction grating, 107: line sensor, 200: ophthalmic image processing device, 201: OCT imaging device control means, 210: ophthalmic image processing device main body, 211: OCT imaging device control means, 212: OCT data acquisition means, 213: image processing means, 214: display control means, 300: operation means, 400: storage means, 500: display means, E: subject's eye, Ef: fundus

Claims

1. An acquisition means for acquiring three-dimensional data of an eye to be examined; An area division means for performing a process of dividing the three-dimensional data into a plurality of depth areas in the depth direction of the eye to be examined; An area selection means for selecting at least two depth areas out of the plurality of depth areas; A front image generation means for performing a projection process on each of the at least two depth areas to generate a front image for each depth area; A composite front image generation means for performing a process of synthesizing the front images generated for each depth area to generate a composite front image; An image processing apparatus, characterized by comprising the above.

2. Further comprising an assignment means for assigning the projection process to each of the at least two depth areas, The front image generation means generates the front image for each depth area by performing the projection process assigned by the assignment means on each of the depth areas. The image processing apparatus according to Claim 1, characterized by this.

3. The assignment means assigns different projection processes to two depth areas out of the at least two depth areas. The image processing apparatus according to Claim 2, characterized by this.

4. The assignment means assigns the same projection process to two depth areas out of the at least two depth areas. The image processing apparatus according to Claim 2, characterized by this.

5. The composite front image is a black-and-white image. The image processing apparatus according to Claim 1, characterized by this.

6. The composite front image generation means generates the composite front image by an addition process of weighting the front images generated for each depth area. The image processing apparatus according to Claim 1, characterized by this.

7. Further comprising an image adjustment means for performing tone adjustment on each of the front images generated for each depth area. The image processing apparatus according to Claim 1, characterized by this.

8. Furthermore, the image adjustment means performs brightness adjustment on the composite front image. The image processing apparatus according to Claim 7, characterized by this.

9. The at least two depth areas selected by the area selection means are areas adjacent in the depth direction of the eye to be examined. The image processing apparatus according to Claim 1, characterized by this.

10. The area selection means selects one depth area out of the plurality of depth areas, The image processing apparatus according to claim 1, further comprising display control means for alternately displaying a frontal image of one depth region generated by performing projection processing on the selected one depth region by the frontal image generation means and the composite frontal image.

11. The image processing apparatus according to claim 1, wherein the at least two depth regions are all regions of the plurality of depth regions.

12. The image processing apparatus according to claim 1, wherein the composite frontal image generation means is capable of generating a composite frontal image obtained by synthesizing frontal images generated for each depth region by assigning different color information to each other.

13. The at least two depth regions include a region corresponding to the vitreous layer of the eye to be examined, a region corresponding to the retinal layer of the eye to be examined, and a region corresponding to the choroid layer of the eye to be examined. The image processing apparatus according to claim 2, wherein the allocation means allocates projection processing by the MIP method to the region corresponding to the vitreous layer and the region corresponding to the retinal layer, and allocates projection processing by the AIP method to the region corresponding to the choroid layer.

14. The three-dimensional data is three-dimensional OCT motion contrast data obtained by processing a plurality of OCT signals at different times at the same position of the eye to be examined. The image processing apparatus according to claim 1, wherein the frontal image is an OCT motion contrast frontal image based on the three-dimensional OCT motion contrast data.

15. The three-dimensional data is three-dimensional OCT intensity data indicating the intensity of the OCT signal. The image processing apparatus according to claim 1, wherein the frontal image is an OCT intensity frontal image based on the three-dimensional OCT intensity data.

16. The image processing apparatus according to claim 1, wherein the region dividing means divides the depth direction of the fundus of the eye to be examined in the three-dimensional data into the plurality of depth regions based on layer boundary information of the layers constituting the fundus of the eye to be examined.

17. The image processing apparatus according to claim 1, wherein the region dividing means divides the three-dimensional data into the plurality of depth regions at a predetermined depth in the depth direction of the eye to be examined.

18. The image processing apparatus according to claim 1, wherein the region selecting means selects the at least two depth regions based on the frequency distribution of the presence of pixels having a predetermined pixel value or more in the three-dimensional data.

19. The image processing apparatus according to claim 1, wherein the region selection means selects the at least two depth regions based on an average pixel value in a direction intersecting the depth direction of the eye to be examined in the three-dimensional data.

20. The image processing apparatus according to claim 1, wherein the region selection means selects the at least two depth regions based on an average pixel value for each of the plurality of depth regions.

21. The image processing apparatus according to claim 1, further comprising display control means for performing control to display the synthesized front image on a screen for receiving an instruction to re-acquire the three-dimensional data or on a screen for analyzing the three-dimensional data.

22. The screen for analyzing the three-dimensional data is a screen for comparing the three-dimensional data with three-dimensional data of the eye to be examined acquired at a date and time different from the date and time when the three-dimensional data was acquired, according to claim 21.

23. The image processing apparatus according to claim 21, further comprising report creation means for creating a report including the synthesized front image, wherein the display control means performs control to display the report created by the report creation means on the screen.

24. An image processing method, comprising: an acquisition step of acquiring three-dimensional data of an eye to be examined; a region division step of performing a process of dividing the three-dimensional data into a plurality of depth regions in the depth direction of the eye to be examined; a selection step of selecting at least two depth regions from the plurality of depth regions; a front image generation step of performing projection processing on each of the at least two depth regions to generate a front image for each depth region; a synthesized front image generation step of performing a process of synthesizing the front images generated for each depth region to generate a synthesized front image. characterized by having the above steps.

25. A program for causing a computer to function as each means of the image processing apparatus according to any one of claims 1 to 23.

Images