JP7753713B2 - Ophthalmic image processing program and ophthalmic image processing device - Google Patents

Description

This disclosure relates to an ophthalmic image processing program and an ophthalmic image processing device.

By performing various processes on OCT data obtained by optical coherent tomography (OCT), various information can be obtained depending on the processing content. For example, images showing the morphology (structure) of the subject's eye and analysis results related to the morphology (structure) can be obtained. The examiner uses the various information obtained from the OCT data to understand the condition of the subject's eye.

For example, the fundus has a layered structure based on the composition of nerve cells, etc. The layered structure of the fundus can be visualized using OCT data.

For example, several vascular networks exist at different depths in the fundus. Furthermore, for example, a vascular network caused by neovascularization may occur near a lesion. The vascular structure in the vascular network is visualized using motion contrast data. Motion contrast data is generated based on multiple OCT data taken at different times at the same measurement position. Motion contrast is information that captures, for example, blood flow in the subject's eye and changes in retinal tissue.

Patent Document 1 discloses a technology that generates a vascular analysis map based on motion contrast data and a morphological analysis map based on OCT data for a common layer region and displays them side by side, making it easy to compare the two.

Japanese Patent Application Laid-Open No. 2017-077414

In the fundus, the depth position of each layer and the depth position of each vascular network do not necessarily coincide anatomically. Furthermore, when observing a lesion, OCT data is used to determine the size of the lesion, while motion contrast data may be used to identify the abnormal vascular network associated with the lesion. In this case, the lesion and the abnormal vascular network that the examiner wants to confirm may be located at different depth positions.

For this reason, it may be desirable to compare information based on OCT data with information based on motion contrast data, such as vascular images or vascular analysis maps, between different layer regions.

The inventor therefore investigated a method for more appropriately setting the areas to be compared for both information based on OCT data and information based on motion contrast data.

In consideration of at least one of the problems of the prior art, the technical objective of the present disclosure is to provide an ophthalmic image processing program and an ophthalmic image processing device that can effectively compare information based on OCT data and information based on OCT motion contrast data.

An ophthalmologic image processing program according to a first aspect of the present disclosure is executed by a processor of a computer, and includes: an acquisition step of acquiring three-dimensional OCT data and three-dimensional motion contrast data of a subject's eye; a setting step of setting a first slab for the three-dimensional OCT data and a second slab for the three-dimensional motion contrast data , wherein depth positions of the first slab and the second slab are set independently; and a setting step of acquiring a front OCT image or a morphological analysis map based on the first slab of the three-dimensional OCT data as first information, and setting a front motion contrast image or a morphological analysis map based on the second slab of the three-dimensional motion contrast data as first information . An ophthalmologic image processing program that causes a computer to execute a calculation processing step of acquiring an image or a vascular analysis map as second information, and a display control step of simultaneously displaying the first information and the second information, wherein the setting step includes a first setting step of setting the first slab or the second slab for either the three-dimensional OCT data or the three-dimensional motion contrast data, and a second setting step of setting the first slab or the second slab for the other of the three-dimensional OCT data and the three-dimensional motion contrast data according to features included in the section of the slab set in the first setting step.
An ophthalmologic image processing program according to a second aspect of the present disclosure is executed by a processor of a computer to include: an acquisition step of acquiring three-dimensional OCT data and three-dimensional motion contrast data of a subject's eye; a setting step of setting a first slab for the three-dimensional OCT data and a second slab for the three-dimensional motion contrast data, wherein depth positions of the first slab and the second slab are set independently; and a setting step of acquiring a front OCT image or a morphological analysis map based on the first slab of the three-dimensional OCT data as first information, and acquiring a front motion contrast image or a vascular analysis map based on the second slab of the three-dimensional motion contrast data. An ophthalmologic image processing program that causes a computer to execute a calculation step of acquiring a map as second information, and a display control step of simultaneously displaying the first information and the second information, wherein when the first slab and the second slab are set to different depth positions in the setting step, the program further executes a modification step of changing the depthwise positions of the first slab and the second slab in accordance with a common operation input while maintaining the relative positional relationship between the first slab and the second slab, and in the display control step, simultaneously displays the first information based on the first slab and the second information based on the second slab after being changed by the modification step.

An ophthalmological image processing device according to a third aspect of the present disclosure executes the ophthalmological image processing program according to the first or second aspect .

According to the present disclosure, it is possible to more appropriately set the areas to be compared for information based on OCT data and information based on motion contrast data.

1 is a block diagram showing an outline of the present embodiment; FIG. 2 is a diagram illustrating an example of an optical system of an OCT device. FIG. 10 is a diagram illustrating acquisition of motion contrast. FIG. 10 is a diagram showing a comparison screen according to the first embodiment. FIG. 10 is a diagram for explaining an example of slab settings suitable for each disease. FIG. 10 is a diagram showing a comparison screen according to the second embodiment. FIG. 11 is a diagram showing a comparison screen according to the third embodiment. FIG. 13 is a diagram showing a comparison screen according to the fourth embodiment. FIG. 13 is a diagram showing a comparison screen according to the fifth embodiment. FIG. 10 is a diagram showing a display mode of a tomographic image for checking the setting state of a slab.

"overview"
The ophthalmic image processing device (computer) exemplified in the present disclosure executes an ophthalmic image processing program using a processor, thereby executing at least an acquisition step, a setting step, a calculation processing step, and a display control step.

Three-dimensional OCT data of the subject's eye and three-dimensional motion contrast data of the subject's eye are acquired in the acquisition step. For ease of explanation, the motion contrast data will be referred to as "MC data" hereinafter. A first slab in the depth direction is set for the three-dimensional OCT data in the setting step. Similarly, a second slab in the depth direction is set for the three-dimensional MC data. A front image or analysis map based on the first slab of three-dimensional OCT data is acquired as first information in the calculation processing step. A front image or analysis map based on the three-dimensional MC data of the second slab is acquired as second information. The first information and second information are simultaneously displayed in the display control step.

Note that a front image based on 3D OCT data is also referred to as a front OCT image, and an analysis map based on 3D OCT data is also referred to as a morphological analysis map. A front image based on 3D MC data is also referred to as a front MC image, and an analysis map based on 3D MC data is also referred to as a vascular analysis map. Furthermore, front OCT images and front MC images are also referred to as en-face images.

In this embodiment, a slab is, for example, a layer region at a certain depth in each of the OCT data and the MC data. The layer region that becomes a slab may be set to include a region sandwiched between two layer boundaries, or may be set as a region near one of the layer boundaries. Furthermore, a slab may be set automatically based on, for example, a segmentation process for either the OCT data or the MC data. Alternatively, a slab may be set manually based on operational input.

In this embodiment, in the setting step, the depth positions of the first slab for the 3D OCT data and the second slab for the 3D MC data are set independently. In this case, the depth positions of the upper end (hereinafter also referred to as the starting layer) and lower end (hereinafter also referred to as the ending layer) of each slab may be set independently.

For example, even if the region where abnormalities in the layer structure appear due to disease and the region where abnormalities in the vascular network appear are different, the first and second slabs can be set appropriately for each. As a result, the regions to be compared can be set more appropriately, and the first information (a frontal OCT image or morphological analysis map based on the first slab of 3D OCT data) and the second information (a frontal MC image or vascular analysis map based on the second slab of 3D MC data) can be displayed simultaneously.

Furthermore, each analysis map may be, for example, a two-dimensional graph showing the two-dimensional distribution of measurement results for the subject's eye. More specifically, each analysis map may be a color map color-coded according to the measurement value. A morphological analysis map based on 3D OCT data may be, for example, a map of layer thickness, a map of the degree of structural abnormality, or a map of other measurement results. Note that the degree of structural abnormality may be obtained based on a probability distribution obtained by inputting 3D OCT data into a trained model that obtains a probability distribution for identifying tissue in an image (for more details, see Japanese Patent Application Laid-Open No. 2020-18794 by the present applicant). Furthermore, a vascular analysis map based on 3D MC data may be, for example, a map of vascular density. Furthermore, each analysis map may be a map showing the measurement value itself, a comparison map or deviation map showing the results of comparison with a normal eye, or a follow-up analysis map showing the difference from measurements obtained on other examination dates. For more specific methods for generating morphological analysis maps and vascular analysis maps, please refer to, for example, the above-mentioned Patent Document 1.

<Changing (resetting) the first and second slabs>
The ophthalmologic image processing program of this embodiment may further cause the ophthalmologic image processing device to execute a modification step. The modification step modifies the depthwise positions of the first slab and the second slab while maintaining the relative positional relationship between the first slab and the second slab. In this case, the positional relationship between the centers of the slabs may be maintained before and after the modification, or the positional relationship between the boundary positions of the slabs may be maintained. The first information based on the first slab and the second information based on the second slab after each modification by the modification step are simultaneously displayed by a display control step.

Furthermore, the change step may alternatively execute a first change process or a second change process. This changes the first slab and the second slab using a method appropriate to the process. In the first change process, as described above, the positions of the first slab and the second slab in the depth direction are changed while maintaining the relative positional relationship between the first slab and the second slab. On the other hand, in the second change process, the positions of the first slab and the second slab in the depth direction are changed independently.

<Slab settings using setting information>
Furthermore, for example, a plurality of pieces of setting information defining combinations of depth positions of the first slab and the second slab may be prepared in advance, and in the setting step, one of the plurality of pieces of setting information may be selected for each subject's eye. Each piece of setting information may differ from other pieces of setting information in either or both of the boundary position in the first slab and the boundary position in the second slab. The first slab and the second slab may be set based on the selected setting information.

One of the pre-prepared combinations of depth positions of the first slab and second slab is selected according to the eye to be examined, making it easier to set the first slab and second slab according to the eye to be examined, for example.

In this case, the ophthalmologic image processing program may further cause the ophthalmologic image processing device to execute an operation reception step. In the operation reception step, a selection operation for setting information is received. As a result, the first slab and the second slab are set based on the selected setting information.

<Setting information is prepared for each disease type>
For example, the setting information may be prepared for each type of disease. That is, each setting information may specify a combination of the depth position of the first slab and the depth position of the second slab according to the type of disease. In the setting step, information indicating the type of disease in the subject's eye (hereinafter referred to as disease information) is acquired, and the first slab and the second slab are set to appropriate depth positions according to the type of disease. Therefore, the first information and the second information are displayed appropriately according to the type of disease, and the two can be compared visually.

A disease information acquisition step may further be performed to acquire information identifying disease information in the subject's eye.

Disease information may be acquired, for example, based on operational input by the examiner. Alternatively, disease information may be associated in advance with the subject's ID, etc., as information indicating the subject's past diagnostic and test results, and disease information may be acquired based on the subject's ID, etc.

Alternatively, disease information may be obtained as a processing result of at least one of 3D OCT data, 3D MC data, and other test results (collectively referred to as test data). For example, the test data may be subjected to a process to detect features in the test data. The features referred to here may be features indicative of abnormalities associated with disease. The features to be detected may be, for example, image features that appear when the 3D OCT data and 3D MC data are visualized, or quantitative features that appear when the test data is analyzed. The quantitative features may be features in a morphological analysis map or a vascular analysis map. In this case, features may be detected based on image processing or analysis processing of the 3D OCT data or 3D MC data. The feature detection process may detect a specific type of feature, or may detect multiple types of features while also distinguishing the type of feature. The presence or absence of a feature (and its type) may be entered manually.

<Automatically set one slab when the other is set manually>
Furthermore, for example, in the operation receiving step, an operation for specifying the depth position of the first slab or the second slab for either the three-dimensional OCT data or the three-dimensional MC data may be received as a selection operation.

When the depth position of the first or second slab is specified for either the 3D OCT data or the 3D MC data through a selection operation, the first or second slab for the other (remaining) of the 3D OCT data or the 3D MC data is automatically set according to the specified depth position. In this case, a combination corresponding to the depth position of the first or second slab specified through the selection operation may be selected from multiple combinations of first and second slabs prepared in advance as setting information. Note that in this case, the selection operation may be an operation to specify the upper and lower ends of the first or second slab, an operation to specify a reference position (e.g., the depth position of the center), or an operation to select the tissue for which the first or second slab is to be set.

<Setting one slab according to the characteristics present in the other slab section>
When a first slab or a second slab is set for either the three-dimensional OCT data or the three-dimensional MC data (initial slab setting), the first slab or the second slab may be set for the other (the remaining one) of the three-dimensional OCT data and the three-dimensional MC data according to features included in the slab section of the first slab. In this way, the layer region to be compared between the three-dimensional OCT data and the three-dimensional MC data is appropriately set according to features included in the slab section set in the initial slab setting.

Here, the initial slab setting for one of the 3D OCT data and the 3D MC data may be performed based on a setting operation, for example. Alternatively, the initial slab setting may be set automatically without requiring a setting operation. For example, the first slab or the second slab may be automatically set to a depth region that is predetermined as a default value in one of the 3D OCT data and the 3D MC data.

In either the 3D OCT data or the 3D MC data, features included in a slab section based on the initial slab setting may be features indicative of abnormalities associated with a disease. The process of detecting features from a slab section in either the 3D OCT data or the 3D MC data can use the method described in the section <Setting information is prepared for each disease type>. The presence or absence of a feature (and its type) may also be entered manually. In this case, when the initial slab setting is performed, the first information or second information corresponding to the slab section based on the initial slab setting may be displayed, and an input operation for the presence or absence of a feature (and its type) may be accepted.

First Example
Examples of embodiments of the present disclosure will be described with reference to the drawings. Unless otherwise specified, the device configurations of the examples are the same.

The ophthalmological image processing device 1 shown in Figure 1 processes OCT data and MC data acquired via the OCT device 10.

The ophthalmologic image processing device 1 includes, for example, a control unit 70. The control unit 70 is realized, for example, by a general CPU (Central Processing Unit) 71, flash ROM 72, RAM 73, etc. The flash ROM 72 stores, for example, an ophthalmologic image processing program for processing OCT data and MC data, a program for controlling the operation of the OCT device 10 to obtain OCT data and MC data, initial values, etc. The RAM 73 temporarily stores, for example, various information.

As shown in FIG. 1, the control unit 70 is electrically connected to, for example, a memory unit (e.g., non-volatile memory) 74, an operation unit 76, and a display unit 75. The memory unit 74 is, for example, a non-transitory storage medium that can retain its contents even if the power supply is cut off. For example, a hard disk drive, flash ROM, a removable USB memory, etc. can be used as the memory unit 74.

The examiner inputs various operational instructions to the operation unit 76. The operation unit 76 outputs signals corresponding to the input operational instructions to the CPU 71. The operation unit 76 may be at least one user interface, such as a mouse, joystick, keyboard, or touch panel.

The display unit 75 may be a display built into the main body of the apparatus 1, or a display connected to the main body. For example, a display of a personal computer (hereinafter referred to as "PC") may be used. The display unit 75 displays, for example, OCT data and MC data acquired by the OCT device 10.

The ophthalmological image processing apparatus 1 of the first embodiment is connected to, for example, an OCT device 10. The ophthalmological image processing apparatus 1 may be, for example, an integrated configuration housed in the same housing as the OCT device 10, or may be a separate configuration. The control unit 70 may acquire MC data from the connected OCT device 10. The control unit 70 may acquire the OCT data and MC data acquired by the OCT device 10 via a storage medium.

<OCT device>
An outline of the OCT device 10 will be described below with reference to Fig. 2. For example, the OCT device 10 irradiates the subject's eye E with measurement light and acquires an OCT signal obtained from the reflected light and the measurement light. The OCT device 10 mainly includes, for example, an OCT optical system 100.

<OCT optical system>
The OCT optical system 100 irradiates the subject's eye E with measurement light and detects an interference signal between the reflected light and reference light. The OCT optical system 100 mainly includes, for example, a measurement light source 102, a coupler (light splitter) 104, a measurement optical system 106, a reference optical system 110, and a detector 120. For a detailed configuration of the OCT optical system, please refer to, for example, Japanese Patent Application Laid-Open No. 2015-131107.

The OCT optical system 100 is an optical system for optical coherence tomography (OCT). The OCT optical system 100 splits light emitted from a measurement light source 102 into measurement light (sample light) and reference light using a coupler 104. The split measurement light is guided to a measurement optical system 106, and the reference light is guided to a reference optical system 110. The measurement light is guided to the fundus Ef of the subject's eye E via the measurement optical system 106. The detector 120 then receives interference light resulting from the combination of the measurement light reflected by the subject's eye E and the reference light.

The measurement optical system 106 includes, for example, a scanning unit (e.g., an optical scanner) 108. The scanning unit 108 may be provided to scan the measurement light in the X and Y directions (transverse directions) on the fundus, for example. For example, the CPU 71 controls the operation of the scanning unit 108 based on set scanning position information, and acquires an OCT signal based on the received light signal detected by the detector 120. The reference optical system 110 generates reference light to be combined with reflected light acquired by reflection of the measurement light at the fundus Ef. The reference optical system 110 may be a Michelson type or a Mach-Zehnder type.

Detector 120 detects the interference state between the measurement light and the reference light. In the case of Fourier-domain OCT, the detector 120 detects the spectral intensity of the interference light, and a depth profile (A-scan signal) within a specified range is obtained by Fourier transforming the spectral intensity data.

In addition, the OCT device 10 may be, for example, a spectral-domain OCT (SD-OCT), a swept-source OCT (SS-OCT), or a time-domain OCT (TD-OCT).

<Frontal shooting optical system>
The front imaging optical system 200, for example, images the fundus Ef of the subject's eye E from a front direction (for example, the optical axis direction of the measurement light) to obtain a front image of the fundus Ef. The front imaging optical system 200 may be, for example, a scanning laser ophthalmoscope (SLO) device configuration (for example, see Japanese Patent Application Laid-Open No. 2015-66242), or may be a so-called fundus camera type configuration (for example, see Japanese Patent Application Laid-Open No. 2011-10944). Note that the OCT optical system 100 may also be used as the front imaging optical system 200, and the front image may be obtained based on a detection signal from the detector 120.

<Fixation target projection unit>
The fixation target projection unit 300 has an optical system for guiding the gaze direction of the eye E. The projection unit 300 has a fixation target to be presented to the eye E, and can guide the eye E. For example, the fixation target projection unit 300 has a visible light source that emits visible light, and changes the presentation position of the fixation target two-dimensionally. This changes the gaze direction, and as a result, changes the location from which OCT data is acquired.

<OCT data acquisition>
The ophthalmologic image processing apparatus 1 of the first embodiment may acquire three-dimensional OCT data of the subject's eye via, for example, the OCT device 10. The OCT optical system 100 scans the subject's eye two-dimensionally with measurement light, thereby acquiring three-dimensional OCT data of the fundus Ef. For example, the CPU 71 controls the driving of the scanning unit 108 to scan the area A1 on the fundus Ef with the measurement light. Note that in FIG. 3( a), the direction of the z-axis is the direction of the optical axis of the measurement light. The direction of the x-axis is perpendicular to the z-axis and corresponds to the left-right direction of the subject. The direction of the y-axis is perpendicular to the z-axis and corresponds to the up-down direction of the subject.

For example, the CPU 71 scans the measurement light in the x direction along scan lines SL1, SL2, ..., SLn in area A1. Scanning the measurement light in a direction intersecting the optical axis direction of the measurement light (e.g., the x direction) is called a "B scan." 3D OCT data is acquired by arranging multiple 2D OCT data acquired by B scans on different scan lines.

<Acquisition of MC data>
Furthermore, the ophthalmologic image processing apparatus 1 of the first embodiment may acquire MC (motion contrast) data by processing OCT data detected by the OCT device 10, for example. The motion contrast may be information capturing, for example, blood flow in the subject's eye or changes in retinal tissue. When acquiring MC data, the CPU 71 acquires at least two pieces of OCT data at different times for the same position on the subject's eye. For example, for each scanning line, the CPU 71 performs multiple B-scans at different times to acquire multiple pieces of OCT data at different times.

For example, Figure 3(b) shows OCT signals acquired when multiple B-scans are performed at different times on scan lines SL1, SL2, ..., SLn. For example, Figure 3(b) shows a case where scan line SL1 is scanned at times T11, T12, ..., T1N, scan line SL2 is scanned at times T21, T22, ..., T2N, and scan line SLn is scanned at times Tn1, Tn2, ..., TnN. For example, the CPU 71 acquires multiple OCT data sets at different times on each scan line and stores the OCT data in the memory unit 74.

Once the CPU 71 acquires multiple pieces of OCT data for the same position at different times as described above, it processes the OCT data to acquire MC data (see Figure 3(c)). Methods for calculating OCT data to acquire motion contrast include, for example, calculating the intensity difference of complex OCT data, calculating the phase difference of complex OCT data, calculating the vector difference of complex OCT data, multiplying the phase difference and vector difference of complex OCT signals, and using signal correlation (correlation mapping). For an example of a calculation method, see JP 2015-131107 A.

The CPU 71 also acquires three-dimensional MC data of the subject's eye E by arranging MC data (two-dimensional MC data) from different scanning lines. The aforementioned three-dimensional OCT data may be formed from the OCT data that forms the basis of the MC data.

<Segmentation processing>
In this embodiment, segmentation processing is performed on each of the 3D OCT data and the 3D MC data. That is, the CPU 71 separates each of the 2D OCT data constituting the 3D OCT data and each of the 2D MC data constituting the 3D MC data into a plurality of depth regions through segmentation processing.

In the first embodiment, the CPU 71 may separate depth regions based on the boundaries of retinal layers detected by image processing of the intensity image. Here, the intensity image is, for example, an image in which brightness values are determined according to the intensity of the OCT signal. For MC data, the CPU 71 may separate depth regions based on the boundaries of retinal layers detected by segmentation processing of the OCT data that forms the basis of the MC data.

<Display Control in First Embodiment>
4, in the first embodiment, a front OCT image 501 based on the three-dimensional OCT data and a front MC image 502 based on the three-dimensional MC data are simultaneously displayed. For convenience, the screens shown in FIG. 4 (or FIGS. 6 to 9) are referred to as comparison screens.

The front OCT image 501 and the front MC image 502 may be obtained, for example, by extracting 3D OCT data and 3D MC data, respectively, for at least a portion of the depth direction (see, for example, Japanese Patent Application No. 2015-121574). For example, the front OCT image 501 and the front MC image 502 may be generated using the integrated value or maximum value in the depth direction of the 3D OCT data and the 3D MC data. However, the method of projecting each 3D data onto the front image is not necessarily limited to this.

In the following description, the depth region corresponding to the front OCT image 501 is referred to as the first slab, and the depth region corresponding to the front MC image 502 is referred to as the second slab.

As shown in Figure 4, a 2D OCT image 511 and a 2D MC image 512 acquired on one of the scan lines are displayed simultaneously with a front OCT image 501 and a front MC image 502. Lines indicating layer boundaries detected by segmentation processing are superimposed on each of the 2D OCT image 511 and the 2D MC image 512.

Furthermore, the boundary position of the first slab corresponding to the front OCT image 501, which is its position on the two-dimensional OCT image 511, is indicated by markers 521a and 521b. Similarly, the boundary position of the second slab corresponding to the front MC image 502, which is its position on the two-dimensional MC image 512, is indicated by markers 522a and 522b. Note that markers 521a and 522a represent the position of the starting layer, and markers 521b and 522b represent the position of the terminal layer, respectively, as the boundary positions of the slabs.

<Setting operations for each slab>
In the first embodiment, when simultaneously displaying a front OCT image 501 and a front MC image 502, the slabs can be different from each other. In the first embodiment, operational inputs regarding the positions of the slabs are accepted via several GUIs. As shown in FIG. 4 , in the first embodiment, the positions of the first slab and the second slab are set via a slab selection unit 530 and a detailed setting unit (offset setting unit) 540. As a result, even if the depth positions of a region where an abnormality in the layer structure appears and a region where an abnormality in the vascular network appears due to a disease are different, the first slab and the second slab can be appropriately set for each depth position. As a result, the examiner can simultaneously confirm the region where the abnormality in the layer structure appears and the region where the abnormality in the vascular network appears as front images corresponding to the respective regions, which is clinically useful.

<Slab selection section>
The slab selector 530 selects one of the multiple depth regions (i.e., slabs) separated by the segmentation process. As described above, in the first embodiment, each slab is set based on the segmentation process of the intensity image (or the OCT data underlying the MC data). In the first embodiment, multiple icons 531 to 538 labeled with slab names are displayed along with thumbnails of the frontal MC image. Note that in FIG. 4, for convenience, the slab names are abstractly written as "Slab 1" to "Slab 8." However, more specific names, such as names commonly used in clinical practice, may also be used. It is desirable that all of the multiple depth regions separated by the segmentation process be included in the combined region of the multiple slabs selectable by the slab selector 530. The multiple slabs selectable by the slab selector 530 may include combinations in which the layer regions partially overlap.

Each icon 531-538 is pre-assigned with its own slab name and two layer boundaries corresponding to it. When one of icons 531-538 is selected, the two layer boundaries corresponding to that icon are set as the reference positions for the first slab and the second slab, respectively. Of the multiple layer boundaries detected by the segmentation process, the layer boundary corresponding to the slab name is used as the reference position.

For example, when icon 531 is selected in FIG. 4, the reference positions of the starting layers of the first and second slabs are set to IPL/INL. Furthermore, the reference positions of the ending layers of the first and second slabs are set to OPL/ONL. In the first embodiment, the set reference positions are displayed as text in the detailed setting section 540. Lines indicating layer boundaries superimposed on the two-dimensional OCT image 511 and the two-dimensional MC image 512 that correspond to the reference positions may be highlighted.

<Detailed settings section>
The detailed setting section 540 allows the start and end positions of the first and second slabs to be input and set as displacements (offset values) relative to a reference position. The detailed setting section 540 allows the start and end positions to be input independently for the first and second slabs. In this embodiment, input of displacements relative to a reference position (input of offset values) is accepted in micrometers.

In the first embodiment, when an operation to change the slab settings (depth position settings) of the first and second slabs is input using the slab selection section 530 and the detailed setting section (offset setting section) 540, the front OCT image 501 and front MC image 502 shown in FIG. 4 are immediately displayed based on the changed slab settings.

For example, the examiner sequentially selects icons 531-538 in the slab selection section 530, and roughly checks for abnormalities in the layer structure or vascular network via the front OCT image 501 and front MC image 502, which change with each selection. Once an abnormality in the layer structure or vascular network has been confirmed, the examiner fine-tunes the boundary position between the first and second slabs via the detailed settings section 540. In this way, while checking the front OCT image 501 and the front MC image 502, the examiner sets each slab so that the abnormality in the layer structure is included in the first slab, and the abnormality in the vascular network is included in the second slab. Furthermore, the examiner can easily compare the front OCT image 501 and the front MC image 502, with each slab set at the desired depth position.

In addition, in the first embodiment, check boxes 551 and 552 are displayed in the GUI as synchronization settings. Depending on the selection operation for each check box 551 or 552, the check mark switches between entered/unentered. If neither check box is entered, as described above, the boundary positions (start and end positions) of each slab can be set to any value for each slab and for each boundary position.

For example, by checking checkbox 551, the offset between images is synchronized. That is, when either the start or end position of the first or second slab is changed in the detailed settings section 540, the same change is applied to the other. In other words, the boundary position of one of the first and second slabs is changed while maintaining the relative positional relationship between them.

Also, for example, by checking checkbox 552, offset changes are synchronized between the start and end positions. For example, when one of the start and end positions of the first slab is changed in the detailed settings section 540, the same change is applied to the other of the first slab (the remaining start and end positions). In other words, the depth position of the slab is changed in response to the operation without changing the width of the slab.

If both checkboxes 551 and 552 are checked, simply changing either the start or end position of the first slab will change the depth position of both the first and second slabs without changing the slab width. In other words, the depth position of each slab is changed while maintaining the relative positional relationship between the first and second slabs.

Second Example
Next, a second embodiment will be described with reference to FIGS.

In the first embodiment, setting the first slab and the second slab to different depth positions required an operation to manually change the depth position of either the first slab or the second slab. In contrast, in the second embodiment, by using predetermined setting information, the first slab and the second slab can be set to different depth positions based on simpler operations.

In the second embodiment, the setting information defines a combination of depth positions of the first slab and the second slab. For example, one setting information defines one boundary position of the first slab (position of the starting layer and position of the ending layer) and one boundary position of the second slab (position of the starting layer and position of the ending layer). In this embodiment, multiple setting information are pre-stored in the storage unit 74. Each of the multiple setting information differs from the other setting information in either or both of the boundary position in the first slab and the boundary position in the second slab. At least one of the multiple setting information includes a combination in which the depth position of the first slab and the depth position of the second slab differ from each other.

In the second embodiment, multiple pieces of setting information may be prepared for each disease type. For example, the boundary positions of the first slab and the second slab may be determined for each disease type so that the first slab contains an abnormal portion of the layer structure corresponding to the disease type, and the second slab contains an abnormal portion of the vascular network corresponding to the disease type. The boundary positions may be determined by a combination of a layer boundary that serves as the reference for the boundary position and an offset from the layer boundary. The layer boundary and offset are determined separately for each of the starting layer and the ending layer. The actual boundary position is a position that is separated by the offset from the layer boundary detected by the segmentation process. The multiple pieces of setting information may be stored in the storage unit 74 as a lookup table that associates the boundary positions of the first slab with the boundary positions of the second slab for each disease type.

Here, specific examples of setting information are shown with reference to Figures 5(a) and (b).

For example, in age-related macular degeneration (AMD), as shown in Figure 5(a), the retinal pigment epithelium (RPE) bulges in a dome shape, and neovascularization occurs around it. Therefore, in the setting information for age-related macular degeneration, the depth position of the first slab may be defined as a range on the superficial side of the RPE. This allows the size of the bulging portion to be properly confirmed. Furthermore, in the setting information for age-related macular degeneration, the depth position of the second slab may be defined as a peripheral region of the RPE, including the RPE. This allows the course of neovascularization to be properly confirmed.

For example, in polypoidal choroidal vasculopathy (PCV), as shown in FIG. 5(b), polypoidal lesions occur superficial to the retinal pigment epithelium (RPE), in a form very similar to the protuberances of age-related macular degeneration. Therefore, in the setting information for polypoidal choroidal vasculopathy, the depth position of the first slab may be determined in the same manner as in the case of age-related macular degeneration. The size of the polypoidal lesions can be appropriately determined via an en face OCT image based on such a slab. Furthermore, in the setting information for polypoidal choroidal vasculopathy, the depth position of the second slab may be determined as the position of the choriocapillaris (CC). The abnormal vascular network in the choriocapillaris can be appropriately confirmed via an en face MC image based on such a slab.

As shown in Figure 6, in the second embodiment, similar to the first embodiment, a front OCT image 501, a front MC image 502, a two-dimensional OCT image, a two-dimensional MC image 512, markers 521a, 521b, 522a, 522b, etc. are displayed.

Furthermore, in the second embodiment, a disease type selection section 560 is displayed as a GUI for selecting one of multiple setting information items. In the disease type selection section 560, icons 561-568 labeled with disease names are displayed. Each icon 561-568 is associated with setting information corresponding to the disease name (i.e., disease type). One of the multiple setting information items is selected based on a selection operation for an icon 561-568. Based on the depth positions of the first slab and second slab specified by the selected setting information, a front OCT image 501 and a front MC image 502 are generated and displayed on the comparison screen.

According to the second embodiment, the examiner selects a disease type via the disease type selection unit 560, and a front OCT image 501 is displayed based on a first slab containing an abnormality in the layer structure corresponding to the disease type. Furthermore, a front MC image 502 is displayed based on a second slab containing an abnormality in the vascular network corresponding to the disease type. Therefore, for example, a front OCT image 501 and a front MC image 502 in which slabs are appropriately set for the desired disease type can be quickly displayed.

In the second embodiment, the same detailed settings section 540 as in the first embodiment is placed on the comparison screen. For example, after a disease type is selected via the disease type selection section 560, the detailed settings section 540 is operated. This allows the boundary positions of the first slab and the second slab to be adjusted independently, based on the boundary position corresponding to the disease type.

Note that Figure 6 illustrates a case where the reference layer boundary is common between the first slab and the second slab in one piece of setting information. However, this is not necessarily limited to this, and the reference layer boundary may be different between the first slab and the second slab in one piece of setting information.

In addition, in the second embodiment, at least one of the 3D OCT data that forms the basis of the front OCT image 501 and the 3D MC data that forms the basis of the front MC image 502 may be processed, and setting information may be automatically selected according to the processing results. As an example, in the third embodiment, the processing results are output as a disease type determination result. The determination results and setting information are associated in advance, and setting information according to the analysis processing results is automatically selected based on this correspondence. The disease type that corresponds to the selected setting information is displayed via the disease type selection unit 560. For example, of the icons 561 to 568, the one that corresponds to the selected disease type is highlighted. Such automatic selection may be performed simultaneously with the screen display, or may be triggered by a specified operational input.

Note that the method for automatically selecting setting information is not limited to the method based on the processing results of 3D OCT data and 3D MC data as described above. For example, if information identifying the subject's disease type as a result of a previous examination is pre-stored in the device, setting information may be selected based on that information.

<Third Example>
7, in the third embodiment, the same images and GUI as those in the first embodiment are displayed. That is, a front OCT image 501, a front MC image 502, a two-dimensional OCT image 511, a two-dimensional MC image 512, markers 521a, 521b, 522a, and 522b, a slab selection section 530, and a detailed setting section 540 are displayed.

In addition, in the third embodiment, a second selection section 570 is further placed on the comparison screen. The second selection section 570 is a GUI in which the disease type selection section 560 in the second embodiment is implemented in the form of a pull-down menu. By expanding the pull-down menu, multiple disease names (disease types) are displayed, and one can be selected. This causes the first slab and the second slab to be set to different depth regions based on the setting information previously associated with the disease type. Note that the disease type may be automatically selected based on the processing results of processing at least one of the 3D MC data that forms the basis of the frontal MC image 502.

Therefore, in the third embodiment, for example, the slab selection unit 530 can be operated to roughly detect abnormal areas, and then appropriate boundary positions for disease differentiation can be set for the first and second slabs. Furthermore, if the disease is already known, appropriate first and second slabs can be quickly set for the desired disease type via the disease type selection unit 560.

<Fourth Example>
In the fourth embodiment, one of the plurality of slabs separated for each vascular network is selected as the second slab, and the first slab is set according to the type of feature of the vascular network included in the second slab of the three-dimensional MC data.

As shown in FIG. 8, for example, in the fourth embodiment, a second slab is selected via the slab selection unit 530. More specifically, any one of the multiple slabs separated for each vascular network can be selected via the slab selection unit 530. In the fourth embodiment, the boundary position of the second slab is set by adding an offset to the layer boundary detected based on the segmentation process of the 3D OCT data. The offset for each layer boundary may be determined in advance.

In a fourth embodiment, features of a vascular network may be detected from a second slab of three-dimensional MC data. Examples of features of a vascular network include ischemia, vascular aneurysms, and neovascularization. Any of a variety of well-known techniques may be applied as appropriate to the detection process for detecting features of a vascular network. Furthermore, features of a vascular network may be detected from three-dimensional MC data within the section of the second slab, or may be detected from a frontal MC image corresponding to the second slab.

In the fourth embodiment, the boundary positions (positions of the start and end layers) of the first slab are set according to the type of feature included in the 3D MC data of the second slab. The position of at least one of the start and end layers of the first slab is set according to the type of vascular network in which the second slab is set and the type of feature in that vascular network.

The detailed setting section 540 in the fourth embodiment is used to adjust the boundary position of the second slab. That is, the start and end positions of the second slab are input and set as displacements (offset values) relative to the reference position. This allows the second slab to be set so that the characteristics of the vascular network are appropriately included. As a result, the first slab can also be set more appropriately according to the type of vascular network characteristics.

In this way, in the fourth embodiment, if characteristic tissue is present in the section corresponding to the front MC image, the front OCT image of the slab to be compared with the front MC image is automatically displayed. This prevents diseases from being overlooked.

Fifth Example
In the fifth embodiment, a plurality of types of comparison screens are prepared in advance, and the initial settings of the slabs are different for each comparison screen.

As shown in Figure 9, in the fifth embodiment, a report screen is displayed as a comparison screen. The report screen displays a report in a format predetermined for each diagnostic purpose, for example. The report is created by extracting a portion of the test result data acquired by the ophthalmologic image processing device 1 according to a report template and arranging it in a predetermined report format that is easy for the user to view. Each template defines the type of data to be extracted and the layout of the extracted data on the report.

In the fifth embodiment, three types of reports are alternatively displayed: a macular disease report, a glaucoma report, and an angio report. The report screen switches depending on the selection of the "Macula" tab 581, the "Glaucoma" tab 582, or the "Angio" tab 583. Here, the macular disease report is used to diagnose macular disease. The glaucoma report is used to diagnose glaucoma. The angio report displays the state of each vascular network at a glance. Of the three types of reports, at least the macular disease report and the glaucoma report are initialized with slabs according to the disease type, and in the initial state, an en face OCT image and an en face MC image for the initialized slab are displayed. In this case, as in the second and third embodiments, the slabs initially set in the macular disease report and the slabs initially set in the glaucoma report are set based on setting information previously associated with each report and the corresponding disease type. For example, in the example shown in Figure 9, for macular disease, at least the ORCC (outer retina to choriocapillaris: a slab including the outer edge of the retinal pigment epithelium to the choriocapillaris (CC)) is set as the initial value of the second slab. Furthermore, for glaucoma, at least the DCP (deep capillary plexus) is set as the initial value of the second slab. However, the initial settings for each disease and slab shown here are merely examples and can be changed as appropriate.

"Variations"
<Display of analysis map reflecting slab settings>
In each embodiment, the comparison screen has been described as simultaneously displaying a front OCT image based on the first slab and a front MC image based on the second slab. However, this is not necessarily limited to this, and a morphological analysis map based on the first slab may be displayed instead of or together with the front OCT image. Similarly, a vascular analysis map based on the second slab may be displayed instead of or together with the front MC image. Each analysis map may be displayed alongside or superimposed on the corresponding front image.

The CPU 71 may analyze the 3D OCT data or 3D MC data for each slab section each time a slab is set, and generate an analysis map as a result of the analysis process and display it on the screen.

<Presetting setting information>
Information defined by the examiner may be preset as the setting information. The preset-registered setting information may be selectable, for example, in the disease type selection unit 560. When the preset is registered, the selection of a layer boundary that serves as a reference for the boundary position and the input of an offset for the layer boundary are accepted for each of the first slab and the second slab. Also, a name may be registered for the setting information defined by the examiner. The registered name is displayed in the disease type selection unit 560 instead of the disease name. Note that the selection of the layer boundary and the input of the offset may be input separately for each of the starting layer and the ending layer.

<Follow-up tests use setting information from previous tests>
In each embodiment, setting information indicating the final setting state of the first and second slabs may be stored in the storage unit 94 as past examination information in association with the subject's identification information. When a new examination is performed on the subject, such as during follow-up observation, and a comparison screen is displayed, the past examination information may be acquired based on the subject's identification information, and slab setting for the 3D OCT data and 3D MC data obtained in the new examination may be performed based on the past examination information. When a new examination is performed, the past examination information may be used as the initial value of the slab setting, or may be used in response to a selection operation by the examiner.
<Display example of tomographic images (2D OCT image, 2D MC image) on the comparison screen>
In each of the first to fourth embodiments, one tomographic image each is displayed to show the setting status of the first and second slabs, along with the front OCT image 501 and the front MC image 502. Specifically, a two-dimensional OCT image 511, a two-dimensional MC image 212, and markers 521a, 521b, 522a, and 522b are displayed.

However, this is not necessarily limited to this, and the setting state of the first and second slabs may also be shown in a layout such as that shown in Figure 10.

As shown in FIG. 10, the setting status of the first and second slabs may be shown using a single tomographic image 600. Markers 611a and 611b indicating the first slab are shown on one side of the tomographic image 600, and markers 612a and 612b indicating the second slab are shown on the opposite side. Furthermore, as shown in FIG. 10, lines indicating layer boundaries identified by segmentation processing of the 2D OCT image may be superimposed on the entire image. Through such a tomographic image 600, the examiner can more intuitively understand the setting status of each slab.

The tomographic image 600 may be a 2D OCT image, a 2D MC image, or a collage image of both. The collage image may be, for example, a tomographic image relating to one scan line, in which a 2D OCT image and a 2D MC image are arranged opposite each other in the transverse direction.

Furthermore, for example, in the above embodiment, when segmentation processing is performed on MC data, segmentation processing is performed on the OCT data that forms the basis of the MC data, and as a result, the boundary positions of each slab in the MC data are set. However, this is not necessarily limited to this. For example, segmentation processing may be performed on the MC data by image processing a two-dimensional MC image based on the MC data.

1 Ophthalmological image processing device 501 Front OCT image 502 Front MC image

Claims (3)

By being executed by a computer processor,
an acquisition step of acquiring three-dimensional OCT data and three-dimensional motion contrast data of the subject's eye;
a setting step of setting a first slab for the three-dimensional OCT data and a second slab for the three-dimensional motion contrast data , wherein depth positions of the first slab and the second slab are set independently;
a calculation step of acquiring, as first information, an en face OCT image or a morphological analysis map based on the first slab of the three-dimensional OCT data, and acquiring, as second information, an en face motion contrast image or a vascular analysis map based on the second slab of the three-dimensional motion contrast data;
a display control step of simultaneously displaying the first information and the second information,
The setting step includes:
a first setting step of setting the first slab or the second slab for either the three-dimensional OCT data or the three-dimensional motion contrast data;
a second setting step of setting the first slab or the second slab for the other of the three-dimensional OCT data and the three-dimensional motion contrast data according to a feature included in the section of the slab set in the first setting step;
Ophthalmic imaging programs, including : By being executed by a computer processor,
an acquisition step of acquiring three-dimensional OCT data and three-dimensional motion contrast data of the subject's eye;
a setting step of setting a first slab for the three-dimensional OCT data and a second slab for the three-dimensional motion contrast data, wherein depth positions of the first slab and the second slab are set independently;
a calculation step of acquiring, as first information, an en face OCT image or a morphological analysis map based on the first slab of the three-dimensional OCT data, and acquiring, as second information, an en face motion contrast image or a vascular analysis map based on the second slab of the three-dimensional motion contrast data;
a display control step of simultaneously displaying the first information and the second information,
When the first slab and the second slab are set at different depth positions in the setting step, a change step is further executed in which the positions of the first slab and the second slab in the depth direction are changed in accordance with a common operation input while maintaining the relative positional relationship between the first slab and the second slab;
An ophthalmologic image processing program, wherein the display control step simultaneously displays the first information based on the first slab and the second information based on the second slab after each has been modified by the modification step. 3. An ophthalmologic image processing apparatus that executes the ophthalmologic image processing program according to claim 1.