JP7005382B2 - Information processing equipment, information processing methods and programs - Google Patents

Description

The disclosure of this specification relates to an information processing apparatus, an information processing method and a program.

As an angiography method that does not use a contrast medium, an angiography method (OCT Angiography: OCTA) using Optical Coherence Tomography (OCT) has been proposed. Patent Document 1 discloses that a blood vessel image (hereinafter referred to as an OCTA image) is generated by projecting three-dimensional motion contrast data acquired by OCT onto a two-dimensional plane.

Further, Non-Patent Document 1 discloses a technique for measuring the blood vessel density in the fundus using an OCTA image.

Japanese Unexamined Patent Publication No. 2016-2009198

Kim et al. "Quantiftying Microvasual Density and Morphology in Diabetic Retinopathy Using Spectral-Domain Optical Coherence TomographyAnt.

However, in the conventional technique, it is not possible to easily compare the information on the blood vessel obtained from the motion contrast data and the information on the tomographic structure obtained from the tomographic image.

One of the purposes of the disclosure of the present specification is to easily compare the information on blood vessels obtained from motion contrast data with the information on tomographic structures obtained from tomographic images.

Not limited to the above-mentioned purpose, it is also an action and effect derived by each configuration shown in the embodiment for carrying out the invention described later, and it is also another purpose of the present invention to exert an action and effect which cannot be obtained by the conventional technique. It can be positioned as one.

The information processing device disclosed in this specification is
The blood vessel density obtained from each of the plurality of motion contrast images obtained by photographing the subject eye at different times and the predetermined layer obtained from each of the plurality of tomographic images obtained by photographing the subject eye at the different times . The acquisition method to obtain the layer thickness and
The map and the information are displayed on the display unit by superimposing the information of the other on the map showing one of the blood vessel density and the layer thickness, and the blood vessel density and the layer thickness at the different time are displayed on the graph. A display control means for displaying on the display unit in correspondence with the display control means is provided .
The display control means is changed in the map and the information when the depth range in which at least one of the blood vessel density and the layer thickness is obtained is changed in response to an instruction from the operator. At least one corresponding to the depth range is updated, and at least one of the vessel density and the layer thickness at the different time on the graph is updated corresponding to the changed depth range. , Control the display of the display unit.

According to the disclosure of the present specification, it is possible to easily compare the information on the blood vessel obtained from the motion contrast data and the information on the tomographic structure obtained from the tomographic image.

It is a block diagram which shows an example of the structure of the image processing system which concerns on Example. It is a figure for demonstrating an example of the structure of an eye part, a tomographic image, and a fundus image. It is a flowchart which shows an example of the processing flow of the image processing system which concerns on Example. It is a figure which shows the example which superposed and displayed the blood vessel density map, the retinal layer thickness, and the blood vessel density sector map which concerns on Example 1. FIG. It is a figure which shows the example which superposed and displayed the retinal layer thickness map, the blood vessel density, and the retinal layer thickness sector map which concerns on Example 1. FIG. It is a figure for demonstrating an example of motion contrast data generation which concerns on Example. It is a figure which shows the example which displays the measurement result which concerns on Example 2 with time.

Hereinafter, exemplary examples for carrying out the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative positions of the components, etc. described in the following examples are arbitrary and can be changed according to the configuration of the device to which the present invention is applied or various conditions. Also, in the drawings, the same reference numerals are used between the drawings to indicate elements that are the same or functionally similar.

(Example 1)
In the following examples, an image processing system to which the present invention is applied will be described.

FIG. 1 is a diagram showing a configuration of an image processing system 100 including an image processing device (information processing device) 300 according to the present embodiment. As shown in FIG. 1, in the image processing system 100, the image processing device 300 has a tomographic image capturing device (also referred to as OCT) 200, a fundus image capturing device 400, an external storage unit 500, a display unit 600, and an input via an interface. It is configured by being connected to the unit 700.

The tomographic image capturing device 200 is a device that captures a tomographic image of the eye portion. The device used for the tomographic imaging device is, for example, SD-OCT or SS-OCT. Since the tomographic image capturing apparatus 200 is a known apparatus, detailed description thereof will be omitted, and here, the imaging of the tomographic image performed according to the instruction from the image processing apparatus 300 will be described.

In FIG. 1, the galvano mirror 201 is for scanning the fundus of the measurement light, and defines the imaging range of the fundus by OCT. Further, the drive control unit 202 controls the drive range and speed of the galvano mirror 201 to define the shooting range in the plane direction and the number of scanning lines (scanning speed in the plane direction) in the fundus. Here, the galvano mirror is shown as one unit for the sake of simplicity, but it is actually composed of a mirror for X scan and two mirrors for Y scan, and a desired range can be scanned with measurement light on the fundus. ..

The focus 203 is for focusing on the retinal layer of the fundus through the anterior segment of the eye, which is the subject. The measurement light is focused on the retinal layer of the fundus through the anterior segment of the eye, which is the subject, by a focus lens (not shown). The measured light that illuminates the fundus is reflected and scattered by each retinal layer and returned.

The internal fixation lamp 204 includes a display unit 241 and a lens 242. A display unit 241 in which a plurality of light emitting diodes (LDs) are arranged in a matrix is used. The lighting position of the light emitting diode is changed according to the part to be photographed by the control of the drive control unit 202. The light from the display unit 241 is guided to the eye to be inspected through the lens 242. The light emitted from the display unit 241 is, for example, 520 nm, and the drive control unit 202 displays a desired pattern.

The coherence gate stage 205 is controlled by the drive control unit 202 in order to cope with the difference in the axial length of the eye to be inspected. The coherence gate represents a position where the optical distances of the measurement light and the reference light in OCT are equal. Further, by controlling the position of the coherence gate as an imaging method, it is possible to control the imaging on the retinal layer side or the deeper side than the retinal layer. Here, the structure of the eye and the image acquired by the image processing system will be described with reference to FIG.

FIG. 2A shows a schematic diagram of the eyeball. In FIG. 2A, C is the cornea, CL is the crystalline lens, V is the vitreous body, M is the macula (the central part of the macula represents the fovea centralis), and D represents the optic nerve head. The tomographic imaging apparatus 200 according to the present embodiment mainly describes a case of photographing the posterior pole of the retina including the vitreous body, the macula, and the optic disc. Although not described in the present invention, the tomographic imaging apparatus 200 can also image the anterior segment of the cornea and the crystalline lens.

FIG. 2B shows an example of a tomographic image when the retina acquired by the tomographic image capturing apparatus 200 is photographed. In FIG. 2B, AS represents a unit of image acquisition in an OCT tomographic image called A scan. A plurality of A scans are performed in the direction of x in the figure to form one B scan. And this B scan is called a tomographic image (or tomographic image). In FIG. 2B, Ve represents a blood vessel, V represents a vitreous body, M represents the macula, and D represents the optic nerve head. L1 is the boundary between the internal limiting membrane (ILM) and the nerve fiber layer (NFL), L2 is the boundary between the nerve fiber layer and the ganglion cell layer (GCL), and L3 is the inner segment outer segment junction of photoreceptor cells (ISOS). ), L4 represents the retinal pigment epithelial layer (RPE), L5 represents the Bruch membrane (BM), and L6 represents the choroid. In the tomographic image, the horizontal axis (main scanning direction of OCT) is the x-axis, and the vertical axis (depth direction) is the z-axis.

FIG. 2C shows an example of a fundus image acquired by the fundus imaging apparatus 400. The fundus image capturing device 400 is a device that captures a fundus image of the eye portion, and examples of the device include a fundus camera, an SLO (Scanning Laser Ophothalmoscope), and the like. In FIG. 2 (c), M represents the macula, D represents the optic disc, and the thick curve represents the blood vessels of the retina. In the fundus image, the horizontal axis (OCT main scanning direction) is the x-axis, and the vertical axis (OCT sub-scanning direction) is the y-axis. The device configuration of the tomographic image capturing device 200 and the fundus imaging device 400 may be an integrated type or a separate type.

The image processing device 300 includes an image acquisition unit 301, a storage unit 302, an image processing unit 303, an instruction unit 304, and a display control unit 305. The image acquisition unit 301 includes a tomographic image generation unit 311 and a motion contrast data generation unit 312. The image acquisition unit 301 acquires the signal data of the tomographic image taken by the tomographic image capturing apparatus 200 and performs signal processing to generate the tomographic image and the motion contrast data. In addition, the fundus image data captured by the fundus image capturing device 200 is acquired. Then, the generated tomographic image and fundus image are stored in the storage unit 302. The image processing unit 303 includes a preprocessing unit 331, an image generation unit 332, and a detection unit 333.

The pre-processing unit 331 performs a process of removing an artifact from the motion contrast data. The image generation unit 332 generates a two-dimensional motion contrast front image (also referred to as an OCTA image) from the three-dimensional motion contrast data. The detection unit 333 detects the boundary line of each layer from the retina.

The external storage unit 500 holds information about the eye to be inspected (patient's name, age, gender, etc.) in association with captured image data, imaging parameters, image analysis parameters, and parameters set by the operator.

The input unit 700 is, for example, a mouse, a keyboard, a touch operation screen, or the like, and the operator gives instructions to the image processing device 300, the tomographic image capturing device 200, and the fundus image capturing device 400 via the input unit 700.

Next, the processing procedure of the image processing apparatus 300 of the present embodiment is shown with reference to FIG.

<Step S301>
In step S301, the eye to be inspected is scanned and an image is taken. When the operator selects the start of a scan (not shown) for scanning the eye to be inspected, the tomographic image capturing apparatus 200 controls the drive control unit 202 and operates the galvano mirror 201 to scan the tomographic image. The galvano mirror 201 is composed of an X scanner for the horizontal direction and a Y scanner for the vertical direction. Therefore, by changing the orientation of each of these scanners, it is possible to scan in each of the horizontal direction (X) and the vertical direction (Y) in the device coordinate system. Then, by changing the orientations of these scanners at the same time, it is possible to scan in the combined direction of the horizontal direction and the vertical direction, so that it is possible to scan in any direction on the fundus plane.

Adjust various shooting parameters when shooting. Specifically, at least the position of the internal fixation lamp, the scan range, the scan pattern, the coherence gate position, and the focus are set. The drive control unit 202 controls the light emitting diode of the display unit 241 to control the position of the internal fixation lamp 204 so as to take an image at the center of the macula or the optic disc. For the scan pattern, a scan pattern such as raster scan, radial scan, or cross scan that captures a three-dimensional volume is set. After the adjustment of these shooting parameters is completed, the operator selects the start of shooting (not shown) to perform shooting.

<Step S302>
In step S302, a tomographic image is generated. The tomographic image generation unit 311 generates a tomographic image by performing a general reconstruction process on each interference signal.

First, the tomographic image generation unit 311 removes fixed pattern noise from the interference signal. Fixed pattern noise removal is performed by extracting fixed pattern noise by averaging a plurality of detected A scan signals and subtracting this from the input interference signal. Next, the tomographic image generation unit 311 performs a desired window function processing in order to optimize the depth resolution and the dynamic range, which are in a trade-off relationship when the Fourier transform is performed in a finite interval. Next, a tomographic signal is generated by performing FFT processing.

<Step S303>
In step S303, the motion contrast data generation unit 312 generates motion contrast data. This data generation will be described with reference to FIG. MC shows three-dimensional motion contrast data, and LMC shows two-dimensional motion contrast data constituting the three-dimensional motion contrast data. Here, a method for generating this LMC will be described.

The motion contrast data generation unit 312 first corrects the positional deviation between a plurality of tomographic images taken in the same range of the eye to be inspected. The method for correcting the misalignment may be any method. For example, the motion contrast data generation unit 312 photographs the same range M times, and aligns the tomographic image data corresponding to the same location by using features such as the shape of the fundus. Specifically, one of the M tomographic image data is selected as a template, the similarity with other tomographic image data is obtained while changing the position and angle of the template, and the amount of misalignment with the template is obtained. .. After that, the motion contrast data generation unit 312 corrects each tomographic image data based on the obtained positional deviation amount.

Next, the motion contrast data generation unit 312 obtains a decorrelation value M (x, z) by Equation 1 between two tomographic image data in which the imaging times for each tomographic image data are continuous with each other.

Here, A (x, z) indicates the luminance at the position (x, z) of the tomographic image data A, and B (x, z) indicates the luminance at the same position (x, z) of the tomographic image data B.

The decorrelation value M (x, z) is a value of 0 to 1, and the larger the difference between the two luminances, the larger the value of M (x, z). When the number of Ms repeatedly acquired at the same position is 3 or more, the motion contrast data generation unit 312 can obtain a plurality of decorrelation values M (x, z) at the same position (x, z). The motion contrast data generation unit 312 can generate final motion contrast data by performing statistical processing such as maximum value calculation and average calculation of a plurality of obtained decorrelation values M (x, z). can. When the number of repetitions M is 2, statistical processing such as maximum value calculation and average calculation is not performed, and the decorrelation value M (x, z) of two adjacent tomographic images A and B is the position (x, z). , Z) is the motion contrast value.

The motion contrast calculation formula shown in Equation 1 tends to be susceptible to noise. For example, if there is noise in the non-signal portion of a plurality of tomographic image data and the values are different from each other, the decorrelation value becomes high and the noise is superimposed on the motion contrast image. In order to avoid this, the motion contrast data generation unit 312 can treat the portion of the tomographic data having a luminance value below a predetermined threshold value as noise and replace the motion contrast value in the portion with zero as preprocessing. .. As a result, the image generation unit 332 can generate a motion contrast image with the influence of noise reduced based on the generated motion contrast data.

<Step S304>
In step S304, the detection unit 333 detects the boundary line of the retinal layer from the tomographic image taken by the tomographic image capturing apparatus 200. The boundary line may be detected from a single tomographic image, or may be detected from an averaging image obtained by averaging a plurality of tomographic images acquired when generating a motion contrast image. good. The detection unit 333 detects each boundary of L1 to L6 in the tomographic image of FIG. 2B, or any of the GCL / IPL, IPL / INL, INL / OPL, and OPL / ONL boundaries (not shown). The detection unit 333 creates an image by applying a median filter and a Sobel filter to the tomographic image to be processed (hereinafter, referred to as a median image and a Sobel image). Next, the detection unit 333 creates a profile for each A scan from the created median image and Sobel image. The median image has a luminance value profile, and the Sobel image has a gradient profile. Then, the detection unit 333 detects the peak in the profile created from the Sobel image. By referring to the profile of the median image corresponding to before, after, and between the detected peaks, the detection unit 333 detects the boundary of each region of the retinal layer. The detection unit 333 can measure the desired layer thickness of the retinal layer from the distance between the detected boundaries of the retinal layer, and stores the measured thickness of the retinal layer in the storage unit 302.

For the tomographic image that detects the boundary of the retinal layer, the boundary positions of the retinal layer obtained from each tomographic image are averaged using a plurality of tomographic images of the same region that are different in time and used for motion contrast data generation in step S303. It is also possible to measure the thickness of the retinal layer.

<Step S305>
In step S305, the image generation unit 332 measures the blood vessel density using the motion contrast data. First, the image generation unit 332 projects the motion contrast data in a depth range for measuring the blood vessel density, and generates an OCTA image (OATA EnFace image). For the depth range in which the blood vessel density is measured, a UI (User Interface) for selecting the retinal layer is provided so that the user can select from a plurality of retinal layers corresponding to the boundary line of the retinal layer detected in step S304. It is possible to configure. Further, the depth range may be a depth range defined by default. As the projection method for generating the OCTA image, either maximum value projection (MIP; Maximum Industry Projection) or average value projection (AIP; Average Industry Projection) can be arbitrarily selected. In order to make the projection method selectable, it is possible to provide a UI for selecting the projection method and configure it so that the user can select it. Subsequently, the image generation unit 332 carries out a process for specifying the blood vessel region. To specify the blood vessel region, for example, the OCTA image is binarized, and the region having a luminance value larger than 0 is defined as the blood vessel region. The image generation unit 332 can measure the blood vessel density VAD in the OCTA image by calculating the area of the specified blood vessel region. VAD is an abbreviation for Vessel Area Density, and is a blood vessel density (unit:%) defined by the ratio of the blood vessel region included in the measurement target. That is, VAD is the blood vessel area density. The method for measuring the blood vessel density VAD is not limited to the above example, and can be realized by using various known methods.

Further, the image generation unit 332 performs a thinning process on the binary image obtained by performing the binarization process on the OCTA image, so that the line width of one pixel corresponding to the center line of the blood vessel is obtained. A binary image can be generated. Then, the blood vessel density VLD can be measured from the total length of the blood vessels obtained by measuring the pixels (pixels corresponding to the blood vessels) whose luminance value is larger than 0 in the binary image. VLD is an abbreviation for Vessel Length Density, and is a blood vessel density defined by the total length of blood vessels contained per unit area (unit: mm ^-1 ). That is, VLD is the blood vessel length density. The method for measuring the blood vessel density VLD is not limited to the above example, and can be realized by using various known methods.

After the measurement, the image generation unit 332 stores the measurement result (VAD, VLD) in the storage unit 302.

<Step S306>
In step S306, the display control unit 305 causes the display unit 600 to display the analysis map based on the thickness measurement result of the retinal layer stored in the storage unit 302 and the blood vessel density measurement result. For example, the display control unit 305 acquires the measurement results of the layer thickness of the retinal layer and the blood vessel density in the depth range in which the blood vessel density is measured from the storage unit 302 and displays them on the display unit 600. That is, the display control unit 305 functions as an example of the acquisition means for acquiring the blood vessel density obtained from the motion contrast image of the test eye and the layer thickness of the predetermined layer obtained from the tomographic image of the test eye.

The analysis map displayed in this embodiment will be described with reference to FIGS. 4 and 5. 4 (a), 4 (b), 5 (a), and 5 (b) are screen examples for displaying the analysis result. In the figure, 1001 shows a map of the retinal layer thickness or the blood vessel density selected by the selection list 1002 described later. In the figure, 1002 shows a selection list for selecting the analysis map to be displayed. In this embodiment, the retinal layer thickness, the blood vessel density (VAD), and the blood vessel density (VLD) are selected by selecting the map to be displayed from the list. ) Is configured so that each map can be switched and displayed. The analysis map is, for example, a color map showing the layer thickness or the blood vessel density in colors according to the values.

In the figure, 1003 shows a selection list for selecting the type of sector map to be superimposed and displayed on the selected analysis map. In this embodiment, the retinal layer thickness value and the blood vessel density value VAD are individually set. Alternatively, both are configured to be superimposed and displayed on the analysis map. In the figure, 1005 shows the sector map selected by the selection list 1003. The sector map includes, for example, a figure showing the average value of the retinal layer thickness or the blood vessel density for each sector and the shape of a plurality of sectors. The value (value of layer thickness or blood vessel density) displayed in each sector is not limited to the average value, but may be a median value, a minimum value, or a maximum value.

FIG. 4A is a display example when Vessel Area Density is selected as the analysis map and the retinal layer thickness value is selected as the sector map to be superimposed and displayed on the map. FIG. 4B is a display example in which Vessel Area Density is selected as the analysis map, and the retinal layer thickness value and the blood vessel density value are selected together as the sector map to be superimposed and displayed on the map. In FIG. 4B, 1006 shows the average value of the retinal layer thickness for each sector, and 1007 shows the average value of the blood vessel density for each sector. As shown in FIG. 4B, there may be a plurality of types of information superimposed on the analysis map. When a plurality of types of information are superimposed on the analysis map, they may be displayed in different display formats as shown in FIG. 4 (b). By associating the display form of the information superimposed on the analysis map with the display form of the items in the selection list 1003, it may be possible to identify which information is which type of information. For example, when the retinal layer thickness is shown in white, the retinal layer thickness value of the item in the selection list 1003 may be shown in white.

The depth range in which the retinal layer thickness value is calculated is the same as the depth range in which the blood vessel density (VAD, VLD) is calculated. By doing so, the user can easily compare the layer thickness and the blood vessel density in the depth range (or a predetermined layer) of interest. It is also possible to set the depth range in which the retinal layer thickness value is calculated and the depth range in which the blood vessel density (VAD, VLD) is calculated to be different ranges. In this case, the map 1001 on which the sector map 1005 is superimposed and the tomographic image are displayed side by side, and a line indicating the depth range regarding the map 1001 and the sector map 1005 (for example, two lines indicating the upper and lower ends) is displayed on the tomographic image. The line) may be displayed in an identifiable manner. With such a configuration, it is possible to determine that the depth range of the retinal layer shown by the analysis map and the depth range of the retinal layer shown by the sector map are different.

For example, the line indicating the depth range of the map 1001 and the line indicating the depth range of the sector map 1005 may be superimposed on the tomographic image with different colors or patterns. In this case, the correspondence may be shown by making the color or pattern of the figure of the sector map 1005 the same as the color or pattern of the line indicating the depth range of the sector map 1005 superimposed on the tomographic image.

Even if the depth range in which the retinal layer thickness value is calculated and the depth range in which the blood vessel density (VAD, VLD) is calculated are the same, the depth range is set in order to clearly indicate the depth range. A tomographic image on which the indicated lines (for example, two lines indicating the upper and lower ends) are superimposed may be displayed. In this case, the display control unit 305 accepts the change of the depth range, acquires the layer thickness and the blood vessel density of the changed depth range from the storage unit 302 according to the accepted change, and displays the change as an analysis map or a sector map. Display at 600. In this way, the display control unit 305 functions as an example of the receiving means for accepting changes in the depth range in which the layer thickness and the blood vessel density can be obtained. In addition, when the depth range is changed, the layer thickness and the blood vessel density may be calculated again.

In this embodiment, the blood vessel density sector map is configured not to be displayed in the list of 1003 so that only the same sector map as the map selected in 1002 can be selected. That is, in the example of FIG. 4, the blood vessel density value (VLD) is not displayed in the selection list 1003. It is also possible to display the blood vessel density value (VLD) in the selection list 1003 but not to select it. However, a map other than the sector map of the same type as the map selected in the selection list 1002 may be selectively displayed in the selection list 1003. In FIG. 4, for example, the sector map of the VLD may be selectively displayed in the selection list 1003.

As described above, the display control unit 305 functions as an example of the display control means for superimposing the information of the other on the map showing one of the blood vessel density and the layer thickness and displaying the map and the information on the display unit.

FIG. 5A is a display example when the retinal layer thickness is selected as the analysis map and VAD is selected as the sector map to be superimposed and displayed on the analysis map. FIG. 5B is a display example in which the retinal layer thickness is selected as the analysis map and the retinal layer thickness value and the VAD are selected together as the sector map to be superimposed and displayed on the map. It should be noted that VAD and VLD may be superimposed on the analysis map of the retinal layer thickness, and the combination of display is not limited to the example of FIG.

When displaying a plurality of sector maps superimposed on the analysis map, it is possible to change the character color of the numerical value for each sector map. It is desirable that the character color in the sector map corresponds to the display color of the retinal layer thickness value, the blood vessel density value (VAD), and the blood vessel density value (VLD) in the selection list 1003. By changing the font color, it is possible to facilitate the correspondence between the displayed value and the sector map.

Further, the combination of the analysis map and the sector map to be displayed can be changed by changing the selection of the selection list 1002 and the selection list 1003, but the combination to be displayed at the time of system startup or the change of the eye to be inspected is changed in advance. It is also possible to set to.

<Step S307>
In step S307, it is determined by the operator whether the type of the map to be displayed has been updated. The map to be displayed is updated in the selection list 1002 for selecting the map to be displayed and the selection list 1003 for selecting the type of sector map to be superimposed and displayed on the selected map, as shown in FIGS. 4 and 5. This is done by the operator changing the selection item. If there is no change in the map to be displayed by the judgment of step S307, the process proceeds to step S309. If the map to be displayed is changed by the judgment of step S307, the process returns to step S306, and the analysis map and the sector map are redisplayed based on the selections of the selection lists 1002 and 1003.

<Step S309>
In step S309, the instruction acquisition unit (not shown) acquires an instruction from the outside whether or not to end the acquisition of the tomographic image by the image processing system 100. This instruction is input by the operator using the input unit 700. When the instruction to end the process is acquired, the image processing system 100 ends the process. On the other hand, if shooting is to be continued without ending the processing, the processing is returned to step S301 to continue shooting. As described above, the processing of the image processing system 100 is performed.

According to the configuration and processing described above, by superimposing and displaying a sector map including another type on the analysis map and confirming a plurality of information on the same screen, the correlation of each information can be easily established. You can check.

(Example 2)
In Example 1 described above, an example in which an analysis map and a sector map are superimposed and displayed has been described, but as other information, it is also possible to display the measurement results in chronological order for follow-up observation.

FIG. 7 shows an example of displaying a plurality of measurement results acquired in the follow-up observation together with the measurement time (for example, date).

In this embodiment, the retinal layer thickness value and the blood vessel density value measured in Example 1 are stored in the external storage unit 500 in FIG. 1, for example, in association with the measurement date and the information of the eye to be inspected. Further, when the operator instructs the follow-up display via the input unit 700, the display control unit 305 acquires the past layer thickness value and the blood vessel density measurement result from the external storage device unit 500, and displays the display unit 600. Display. The display control unit 305 functions as an example of acquisition means for acquiring the blood vessel density obtained from the motion contrast image of the test eye and the layer thickness of a predetermined layer obtained from the tomographic image of the test eye at a plurality of time points.

FIG. 7A shows an example in which the average value of the retinal layer thickness value and the blood vessel density value in the entire measurement region is displayed. The layer thickness and vessel density displayed are, for example, in the same depth range (RNFL: Retinal Nerve Fiber Layer). The depth range is not limited to RNFL. As shown in FIG. 7A, the display control unit 305 causes the display unit 600 to display the layer thickness and the blood vessel density in a state where the layer thickness and the blood vessel density correspond to each date. That is, the display control unit 305 causes the display unit to display the blood vessel density and the layer thickness at a plurality of time points in correspondence with each other.

In FIG. 7B, the selection button 1007 for selecting the display sector is displayed, and the operator selects the button via the input unit 700 to display the measured values of the selected sector area in chronological order. An example is shown. The display control unit 305 accepts a change in the position of the plane orthogonal to the depth direction of the eye to be inspected via the selection button 1007. That is, the display control unit 305 functions as an example of the second reception means. The layer thickness and blood vessel density may be recalculated when the change in the position of the plane orthogonal to the depth direction of the eye to be inspected is accepted, or the pre-calculated layer thickness and blood vessel density may be calculated in the external storage unit. It may be obtained from 500.

In FIG. 7, the depth range in which the blood vessel density (VAD, VLD) is calculated is, for example, the RNFL layer. That is, FIG. 7 shows changes in layer thickness and blood vessel density over time in the same depth range. As the change in blood vessel density with time, at least one of VAD and VLD may be displayed, and it is not essential to display both.

It should be noted that a UI for selecting the depth range may be provided in FIG. 7. The display control unit 305 accepts the change of the depth range via the UI for selecting the depth range. That is, the display control unit 305 functions as an example of the first receiving means that accepts changes in the depth range in which the layer thickness and the blood vessel density can be obtained. When the depth range is changed, the layer thickness and the blood vessel density may be calculated again, or the layer thickness and the blood vessel density calculated in advance may be acquired from the external storage unit 500. good. The UI for selecting the depth range may be, for example, a UI that allows the depth range to be selected by moving the layer boundary superimposed on the tomographic image. Specifically, the layer boundary defining the upper end and the layer boundary defining the lower end of the depth range are superimposed and displayed on the tomographic image, and at least one step of the line defining the upper end or the line defining the lower end is moved. You can select the depth range with. The depth range may be selected by providing a pull-down list in which the name of the layer boundary can be selected. In response to such a change in the depth range by the UI, the retinal layer thickness and the blood vessel density displayed as shown in FIG. 7 may be changed. By using such a UI, in FIG. 7B, it is possible to select a sector area and a depth range. In addition, the blood vessel density and the layer thickness of different layers may be displayed as shown in FIGS. 7 (a) and 7 (b). In this case, the display control unit 305 may display the display unit 600 to indicate which layer the blood vessel density is. Further, the display control unit 305 may display a warning indicating that the layer thickness and the blood vessel density are different from each other on the display unit 600.

With the above configuration, it is possible to superimpose and display a plurality of information at the time of follow-up observation, and the correlation of the measurement results can be easily confirmed.

(Modification 1)
Although FIG. 7 shows the time-dependent changes in the layer thickness, VAD and VLD in one layer, the time-dependent changes in the layer thickness, VAD and VLD in a plurality of layers may be shown simultaneously or switchably.

(Example 2)
In Example 1 described above, an example in which an analysis map and a sector map are superimposed and displayed has been described, but as another form, with respect to a difference map between the value of the normal eye database of the retinal layer thickness or the blood vessel density and the measured value. It is also possible to superimpose the sector map. For example, the sector map of the blood vessel density may be superimposed on the color map showing the difference between the normal eye database of the retinal layer thickness and the measured retinal layer thickness value in the color corresponding to the difference value. It is also possible to superimpose a sector map of the retinal layer thickness on a color map showing the difference between the normal eye database of blood vessel density and the measured blood vessel density value in a color corresponding to the difference value.

(Example 3)
In the first embodiment described above, the case where the sector map is superimposed on the analysis map has been described, but the present invention is not limited to this. For example, the motion contrast image (EnFace image) may display at least two sector maps of the retinal layer thickness value, VAD and VLD.

(Other embodiments)
Each of the above embodiments realizes the present invention as an image processing apparatus. However, the embodiment of the present invention is not limited to the image processing apparatus. It is also possible to realize the present invention as software that operates on a computer. The CPU of the image processing device controls the entire computer using computer programs and data stored in RAM and ROM. In addition, the execution of software corresponding to each part of the image processing device is controlled to realize the function of each part. Further, the user interface such as buttons and the layout of the display are not limited to those shown above.

100 Image processing system 200 Tomographic image capturing device 300 Image processing device 301 Image acquisition unit 302 Storage unit 303 Image processing unit 305 Display control unit 311 Tomographic image generation unit 312 Motion contrast data generation unit 331 Preprocessing unit 332 Image generation unit 333 Detection unit 400 Fundus imaging device 500 External storage unit 600 Display unit 700 Input unit

Claims (13)

The blood vessel density obtained from each of the plurality of motion contrast images obtained by photographing the subject eye at different times and the predetermined layer obtained from each of the plurality of tomographic images obtained by photographing the subject eye at the different times . The acquisition method to obtain the layer thickness and
The map and the information are displayed on the display unit by superimposing the information of the other on the map showing one of the blood vessel density and the layer thickness, and the blood vessel density and the layer thickness at the different time are displayed on the graph. A display control means for displaying on the display unit in correspondence with the display control means is provided .
The display control means is changed in the map and the information when the depth range in which at least one of the blood vessel density and the layer thickness is obtained is changed in response to an instruction from the operator. At least one corresponding to the depth range is updated, and at least one of the vessel density and the layer thickness at the different time on the graph is updated corresponding to the changed depth range. , An information processing device that controls the display of the display unit. The blood vessel density includes blood vessel area density and blood vessel length density.
The display control means according to claim 1 , wherein a map showing the layer thickness is displayed on the display unit as the map, and the blood vessel area density and the blood vessel length density are displayed on the display unit as the information. Information processing device. The blood vessel density includes blood vessel area density and blood vessel length density.
The display control means causes the display unit to display a map showing one of the blood vessel area density and the blood vessel length density as the map, displays the layer thickness as the information on the display unit, and displays the blood vessel area density and the blood vessel area density. The information processing apparatus according to claim 1 , wherein the other information of the blood vessel length density is superimposed on the map and displayed on the display unit. The information processing according to claim 2 or 3, wherein the display control means superimposes information of both the blood vessel area density and the blood vessel length density on the motion contrast image of the eye to be inspected so as to be discriminatively superimposed and displayed on the display unit. Device. A first receiving means that accepts a change in the depth range at which at least one of the blood vessel density and the layer thickness can be obtained.
A second receiving means for accepting a change in the position of a plane orthogonal to the depth direction of the eye to be inspected, in which at least one of the blood vessel density and the layer thickness is obtained .
The information processing apparatus according to any one of claims 1 to 4. The display control means superimposes a sector map composed of a plurality of sectors indicating the positions of the planes on the map and displays them on the display unit, and the plurality of values indicating the other information in each of the plurality of sectors. Corresponding to each of the sectors of, superimposed on the map and displayed on the display unit,
The information processing device according to claim 5, wherein the second receiving means accepts a change in the position of the plane by selecting one of the plurality of sectors in response to an instruction from the operator. The display control means superimposes at least two types of information selected in response to an instruction from the operator, including the other information, on the map so as to be identifiable, among the plurality of types. The information processing apparatus according to any one of claims 1 to 6. The display control means according to claims 1 to 7 superimpose information indicating a depth range in which at least one of the blood vessel density and the layer thickness is obtained on the tomographic image of the eye to be inspected and display it on the display unit. The information processing apparatus according to any one of the following items. The layer thickness and the vessel density are values obtained from different depth ranges.
The display control means superimposes the information indicating the depth range in which the blood vessel density is obtained and the information indicating the depth range in which the layer thickness can be obtained on the tomographic image of the eye to be inspected on the display unit. The information processing apparatus according to any one of claims 1 to 8 to be displayed. The information processing apparatus according to any one of claims 1 to 8 , wherein the layer thickness and the blood vessel density are values obtained from the same depth range. The information processing apparatus according to any one of claims 1 to 10.
The information processing includes a scanning means for scanning the measurement light and a drive control means capable of controlling the scanning means so that the measurement light is scanned in the same range of the eye to be inspected in order to obtain the motion contrast image. An imaging device connected to the device so that it can communicate with the device,
A system equipped with. The blood vessel density obtained from each of the plurality of motion contrast images obtained by photographing the subject eye at different times and the predetermined layer obtained from each of the plurality of tomographic images obtained by photographing the subject eye at the different times . The acquisition process to acquire the layer thickness and
The map and the information are displayed on the display unit by superimposing the information of the other on the map showing one of the blood vessel density and the layer thickness, and the blood vessel density and the layer thickness at the different time are displayed on the graph. Including a display control step of correspondingly displaying on the display unit .
In the display control step, when the depth range in which at least one of the blood vessel density and the layer thickness is obtained is changed in response to an instruction from the operator, the map and the information are changed. At least one corresponding to the depth range is updated, and at least one of the vessel density and the layer thickness at the different time on the graph is updated corresponding to the changed depth range. , An information processing method for controlling the display of the display unit . A program characterized by causing a computer to execute the information processing method according to claim 12 .

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