Visual field testing method, visual field testing device, and visual field testing program

Abstract

To provide a visual field inspection device that does not impose a burden on a subject.SOLUTION: A visual field inspection method for inspecting a visual field range divided at least into a first part region and a second part region includes: a step for measuring sensitivity at a plurality of first inspection points included in the first part region; and a step for executing processing to estimate sensitivity at a plurality of second inspection points, which are inspection points other than the first inspection points, included in the first part region, using the sensitivity at the plurality of first inspection points.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The technology disclosed herein relates to a visual field testing method, a visual field testing apparatus, and a visual field testing program. [Background technology]

[0002] Japanese Patent Publication No. 5048284 discloses a visual field testing device for examining the sensitivity of a subject's eye to light stimuli. A visual field testing device that does not burden the subject is desired. [Overview of the Initiative]

[0003] A first aspect of the technology of the present disclosure is a visual field testing method for testing a visual field range divided into at least a first partial region and a second partial region, comprising the steps of: measuring the sensitivity of a plurality of first test points included in the first partial region; and estimating the sensitivity of a plurality of second test points, which are test points other than the first test points and included in the first partial region, using the sensitivity of the plurality of first test points.

[0004] A second aspect of the technology of the present disclosure is a visual field testing apparatus comprising a processor for testing a visual field range divided into at least a first partial region and a second partial region, wherein the processor performs the steps of: measuring the sensitivity of a plurality of first test points included in the first partial region; and estimating the sensitivity of a plurality of second test points, which are test points other than the first test points, included in the first partial region, using the sensitivity of the plurality of first test points.

[0005] A program of a third aspect of the technology of the present disclosure causes a computer to perform the steps of: measuring the sensitivity of a plurality of first inspection points included in the first partial region within a field of view divided into at least a first partial region and a second partial region; and estimating the sensitivity of a plurality of second inspection points, which are inspection points other than the first inspection points and included in the first partial region, using the sensitivity of the plurality of first inspection points. [Brief explanation of the drawing]

[0006] [Figure 1] This is a block diagram of the ophthalmology system 100. [Figure 2] This is a block diagram showing the configuration of the perimeter 110. [Figure 3] This is a functional block diagram of the CPU 22 of the perimeter 110. [Figure 4A] This is an explanatory diagram showing the structure of the 12 eye under examination. [Figure 4B] This is an image of the 190-cell area of ​​a normal fundus, which is the area to be examined. [Figure 4C] This is a schematic diagram showing the set of inspection points 200, which is the set of inspection points where indicator light is presented within the inspection target area 190. [Figure 4D] This is a visual field sensitivity map showing the results of a visual field examination of a normal fundus. [Figure 5A] This is an explanatory diagram showing how the initial inspection points were set from the set of inspection points 200. [Figure 5B] This is an explanatory diagram showing the results of the initial inspection points. [Figure 5C] This is an explanatory diagram showing an example of setting additional test points based on the test results. [Figure 5D] This is an explanatory diagram showing the case where additional inspection points are set. [Figure 5E] This diagram illustrates how to estimate the visual field sensitivity of untested points, indicated by white circles, within the visual field testing area, based on the test results. [Figure 6] This is a schematic diagram showing an example of a visual field sensitivity map of a diseased fundus. [Figure 7] This diagram illustrates the correlation between data interpolation in the upper region 202 and the lower region 204, assuming that the entire visual field examination area of ​​the fundus is interpolated. [Figure 8A] This is an explanatory diagram showing the case where the upper region 202 is subdivided into regions 220, 222, 224, 226, 228, and 230, and the inspection data is interpolated independently in each region. [Figure 8B]It is a schematic diagram when the visual field inspection area is divided into two parts left and right by the vertical meridian 240 passing through the fovea centralis. [Figure 8C] It is a schematic diagram when the visual field inspection area is divided into four parts up, down, left, and right by the horizontal meridian 206 passing through the fovea centralis and the vertical meridian 240 passing through the fovea centralis. [Figure 9] It is a flowchart of the visual field inspection process executed by the CPU 22 of the perimeter 110. [Figure 10] It is a flowchart of the process of estimating and interpolating the visual field sensitivity of all inspection points in step 136 of FIG. 9. [Figure 11A] It is a diagram showing the update process of the cumulative function. [Figure 11B] It is another diagram showing the update process of the cumulative function. [Figure 11C] It is another diagram showing the update process of the cumulative function. [Figure 11D] It is another diagram showing the update process of the cumulative function. [Figure 11E] It is another diagram showing the update process of the cumulative function. [Figure 11F] It is another diagram showing the update process of the cumulative function. [Figure 11G] It is another diagram showing the update process of the cumulative function. [Figure 11H] It is another diagram showing the update process of the cumulative function. [Figure 11I] It is another diagram showing the update process of the cumulative function. [Figure 12] It is an explanatory diagram showing the luminance - positive response rate curve indicating the relationship between the probability fa,b(θ) that the inspection point of the optic nerve of the subject's test eye 12 recognizes the index light of that luminance value with respect to the luminance value. [Figure 13] It is a schematic diagram showing the relationship between the inspection points (including uninspected points and inspected points) and the estimated luminance values of each inspection point. [Figure 14A] It is a schematic diagram showing an example of the inspection result of each inspection point in the case of no abnormality. [Figure 14B] It is a schematic diagram showing an example of the visual field sensitivity map in the case of no abnormality. [Figure 14C] It is a schematic diagram showing the setting of additional inspection points in the case of no abnormality. [Figure 15A] This is a schematic diagram showing examples of examination results for each examination point in the case of nasal perforation in the upper region 202. [Figure 15B] This is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 is punctured nasally. [Figure 15C] The upper region 202 is a schematic diagram showing the setting of additional examination points in the case of nasal perforation. [Figure 16A] This is a schematic diagram showing examples of examination results for each examination point when the upper region 202 has a temporal wedge-shaped defect. [Figure 16B] This is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 has a temporal wedge-shaped defect. [Figure 16C] This is a schematic diagram showing an example of setting additional examination points when the upper region 202 has a temporal wedge-shaped defect. [Figure 17A] This is a schematic diagram showing examples of the test results for each test point when the lower region 204 is a nasal staircase. [Figure 17B] This is a schematic diagram showing an example of a visual field sensitivity map when the lower region 204 is a nasal staircase. [Figure 17C] This is a schematic diagram showing an example of setting additional examination points when the lower region 204 is a nasal staircase. [Figure 18A] This graph shows the estimated brightness value for each test point in the entire set of test points. [Figure 18B] This graph adds confidence levels to the graph in Figure 18A. [Figure 19] This is a diagram showing the field of view sensitivity map for 510M. [Figure 20A] This figure shows the relationship between the number of tests performed and the difference between the correct sensitivity value and the estimated sensitivity in conventional technology. [Figure 20B] This is another figure showing the relationship between the number of tests performed and the difference between the correct sensitivity value and the estimated sensitivity in the conventional technology. [Figure 20C] This is another figure showing the relationship between the number of tests performed and the difference between the correct sensitivity value and the estimated sensitivity in the conventional technology. [Figure 21A]This figure shows the relationship between the number of tests performed and the difference between the correct sensitivity value and the estimated sensitivity in this embodiment. [Figure 21B] This is another figure showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in this embodiment. [Figure 21C] This is another figure showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in this embodiment. [Figure 22] This diagram illustrates a method for interpolating the estimated brightness values ​​of untested points. [Figure 23] This graph shows the estimated luminance value and reliability obtained in this embodiment. [Modes for carrying out the invention]

[0007] Embodiments of the technology of this disclosure will be described in detail below with reference to the drawings.

[0008] Referring to Figure 1, the configuration of the ophthalmology system 100 will be explained. As shown in Figure 1, the ophthalmology system 100 includes a static perimetry device (hereinafter referred to as "perimeter") 110, a management server device (hereinafter referred to as "server") 140, and an image display device (hereinafter referred to as "viewer") 150.

[0009] The perimeter 110 is an example of a "perimeter testing device" of the technology of this disclosure.

[0010] The visual field meter 110 is a device used to examine the visual field sensitivity (luminance value) of the subject's eye, which will be described in detail later, and is used in the diagnosis of glaucoma, retinitis pigmentosa, and other conditions.

[0011] Here, visual field sensitivity refers to the intensity (luminance value: dB) of the indicator light that reaches the target test point on the optic nerve in the retina of the eye being examined and is perceived by the subject. Note that the larger the luminance value expressed in dB, the smaller the intensity of the indicator light reaching the test point. In other words, the smaller the luminance value expressed in dB, the larger the intensity of the indicator light reaching the test point. That is, the larger the luminance value expressed in dB, the dimmer the indicator light, and the smaller the luminance value expressed in dB, the brighter the indicator light.

[0012] Server 140 stores the results of the visual field sensitivity test (estimated sensitivity, etc.) of the subject's eye, obtained by the visual field meter 110, and associates them with the patient ID. Viewer 150 displays medical information, such as the visual field sensitivity test results of the subject's eye, obtained from Server 140.

[0013] The field meter 110, server 140, and viewer 150 are interconnected via network 130.

[0014] Figure 2 shows the configuration of the perimeter 110.

[0015] When the perimeter 110 is placed on a horizontal plane, the horizontal direction is defined as the "X direction," the direction perpendicular to the horizontal plane is defined as the "Y direction," and the direction connecting the center of the pupil of the anterior segment of the eye under examination 12 to the center of the eyeball is defined as the "Z direction." Therefore, the X, Y, and Z directions are perpendicular to each other.

[0016] As shown in Figure 2, the perimeter 110 comprises a control device 10, an indicator presentation unit 30, an external storage device 40, an input / display unit 50, and a response unit 60.

[0017] The control device 10 includes a computer comprising a CPU (Central Processing Unit) 22, ROM (Read-Only memory) 24, RAM (Random Access Memory) 26, and input / output (I / O) ports 28, all interconnected by a bus 20. The ROM 24 stores the visual field examination program, which will be described later.

[0018] CPU22 is an example of a “processor” in the technology of this disclosure. The processor executes a visual field testing program.

[0019] The I / O port 28 is connected to an indicator display unit 30, an external storage device 40, a communication interface (I / F) 45, an input / display unit 50, and a response unit 60.

[0020] The input / display unit 50 has a graphic operator interface for displaying images and receiving various instructions from the operator. A touch panel display is an example of a graphic operator interface.

[0021] The response unit 60 includes a switch (not shown) and a transmitter, which are operated by the subject (patient). During a visual field test, which will be described later, the subject turns on the switch when they recognize the indicator light. When the switch is turned on, the transmitter sends a recognition signal to the control device 10 indicating that the subject has recognized the indicator light.

[0022] The communication interface (I / F) 45 is connected to the server 140 and the viewer 150 via the network 130.

[0023] The indicator presentation unit 30 comprises a dome 30D whose inner surface is a reflective surface and a projection device (not shown) that presents indicators (specifically, projects light) at multiple points on the inner surface of the dome 30D. According to the control of the control device 10, which follows a visual field examination program described later, the projection device presents indicators at multiple points (indicator presentation points) at different locations on the inner surface of the dome 30D at different times. The indicator presentation points correspond to the retina of the eye being examined. The indicator light from the indicator presentation points reaches the examination points on the retina of the eye being examined 12. As described above, the subject who recognizes the indicator light turns on the switch, and the transmission unit transmits a recognition signal to the control device 10.

[0024] In the technology disclosed herein, the configuration of the indicator presentation unit 30 is not limited to a configuration comprising a dome 30D and a projection device. In the technology disclosed herein, for example, a configuration in which points on the inner surface of the dome 30D self-illuminate, or a configuration in which indicator light is directly presented to the examination points on the retina of the eye to be examined 12, can be adopted as the configuration of the indicator presentation unit 30.

[0025] The server 140 and viewer 150 are equipped with a computer with a CPU, RAM, ROM, etc., an input device, a display, and an external storage device, etc.

[0026] Figure 3 shows a functional block diagram of the CPU 22 of the perimeter 110. The various functions realized by the CPU 22 of the perimeter 110 executing the visual field examination program will be explained below. The visual field examination program includes an examination point setting function, an image processing function, and a processing function. When the CPU 22 executes the visual field examination program having these functions, the CPU 22 functions as an examination point setting unit 72, an image processing unit 74, and a processing unit 76, as shown in Figure 3.

[0027] Figure 4A is an explanatory diagram showing the structure of the eye under examination 12. The eyeball constituting the eye under examination 12 is approximately spherical in shape and surrounded by the sclera 170. Inside the sclera 170 is the choroid 172, and inside the choroid 172 is the retina 174. The inside of the eyeball, covered by the retina 174, is filled with a gel-like vitreous humor 176.

[0028] The retina 174 has visual cells arranged in a planar manner, and these visual cells convert visual images (light information) into nerve signals (electrical signals). The nerve signals obtained by the visual cells are transmitted from the optic disc 184 to the brain via the optic nerve 182.

[0029] The macula 178 is a region in the retina 174 where visual cells are densely packed, and the fovea 180, which corresponds to the center of the macula 178, has the highest resolution in the visual field because the visual cells are most densely packed there. On the other hand, the optic disc 184 is the area where the optic nerve 182 converges, and therefore no visual cells are present. As a result, the region on the retina 174 where the optic disc 184 is located becomes the blind spot 186.

[0030] In this embodiment, the visual field sensitivity of the eye under examination 12 is measured, and the region on the retina 174 of the fundus in which visual cells are significantly located is defined as the area to be examined 190.

[0031] Figure 4B is an image of the examination area 190 in a normal fundus of the right eye. The horizontal line crossing the image is the horizontal meridian 206, which is the boundary line between the upper area 202 and the lower area 204 in the visual field examination area. In this embodiment, as will be described later, interpolation of the examination data is performed independently in the upper area 202 and the lower area 204 of the fundus.

[0032] Figure 4C is a schematic diagram showing the set of test points 200, which is a set of test points to which an indicator light is presented in the test area 190. Since there are many test points in the set of test points 200, in this embodiment, a selective test is performed to obtain the subject's response by presenting an indicator light to a few selected test points, and the brightness values ​​of the test points to which the indicator light is not presented are interpolated using a method such as Gaussian regression. As will be described later, in some cases of fundus disease, there is little continuity between the upper region 202 and the lower region 204. In addition, data interpolation such as Gaussian regression is easily influenced by the data of test points adjacent to the test point being interpolated. Therefore, even if there is no disease in the upper region 202, if a disease is found in a test point in the lower region 204 adjacent to the upper region 202, there is a risk that the data will be interpolated to show that normal test points also have a disease if data interpolation is performed on the upper region 202 and the lower region 204 together. In this embodiment, the above-mentioned erroneous interpolation is suppressed by performing data interpolation independently, for example, on the upper region 202 and the lower region 204. Here, "cases" refers to cases of visual field defects in glaucoma. Specifically, these include cases of nasal perforation, nasal staircase, temporal wedge-shaped defects, and arcuate scotoma.

[0033] Figure 4D is a visual field sensitivity map showing the results of a visual field examination of a normal fundus of the right eye. In the visual field sensitivity map, areas with low luminance values ​​indicating visual field sensitivity are shown as dark areas. A dark area 188 is also present in Figure 4D, and this dark area 188 corresponds to the optic nerve head 184, which is the blind spot 186.

[0034] Figures 5A to 5E are explanatory diagrams illustrating the overview of the visual field test. In this embodiment, when the visual field test is started, initial test points, shown in gray, are set from the set of test points 200, as shown in Figure 5A. The set of test points 200 is a set of test points that are the subject of visual field sensitivity testing, each of which is positioned over the range in which the indicator light reaches through the pupil of the eye 12, for example, the optic nerve of the retina of the eye 12. In this embodiment, several initial test points are set from the set of test points 200, and a selective test is performed in which the visual field sensitivity is measured for test points with higher priority, rather than all test points included in the set of test points 200.

[0035] In principle, the initial test points are set regardless of whether or not the subject has previous diagnostic data; however, the initial test points may be set according to the subject's previous diagnostic data. For example, if the previous diagnostic data indicates the presence of areas with low visual field sensitivity, the initial test points may be set with emphasis on the area including those areas. Also, the initial test points do not need to be set symmetrically vertically as shown in Figure 5A; they may be set asymmetrically.

[0036] Figure 5B is an explanatory diagram showing the results of the initial inspection points. In Figure 5B, the inspection points indicated by black triangles are points with poor visual field sensitivity where the visual field sensitivity is below a predetermined threshold, while the inspection points indicated by other squares are points with appropriate visual field sensitivity where the visual field sensitivity exceeds a predetermined threshold.

[0037] Figure 5C is an explanatory diagram showing an example of setting additional test points based on the test results. In Figure 5C, the fundus of the eye 12 being examined is divided into an upper region 202 and a lower region 204 by a horizontal meridian 206 passing through the fovea, which corresponds to the center of the macula. As shown in Figure 5C, many points of poor visual field sensitivity are located in the upper region, so the additional test points indicated by the pentagons are preferentially set in the upper region 202 rather than the lower region 204.

[0038] Figure 5D is an explanatory diagram showing the case where additional inspection points are set. If additional inspection points are set, and the previously set additional inspection points were prioritized in areas with many visual field sensitivity defects, then the same number of additional inspection points, indicated by hexagons, should be set in the upper area 202 and the lower area 204, as shown in Figure 5D. Alternatively, new additional inspection points may be prioritized in areas with many visual field sensitivity defects.

[0039] Figure 5E is an explanatory diagram illustrating how to estimate the visual field sensitivity of untested points indicated by white circles in the visual field testing area based on the test results. As shown in Figure 5E, in this embodiment, the visual field testing area is divided into an upper area 202 and a lower area 204, and the test data is interpolated independently in each area.

[0040] Figure 6 is a schematic diagram showing an example of a visual field sensitivity map of a diseased fundus. The upper region 202 of the visual field sensitivity map contains region 208A, which indicates an upper visual field defect, and the lower region 204 contains region 208B, which indicates a lower visual field defect. In Figure 6, no significant continuity is observed between region 208A, which indicates an upper visual field defect, and region 208B, which indicates a lower visual field defect. In this situation, if data interpolation is performed on the entire set of test points 200, region 208A, which indicates an upper visual field defect, may be enlarged beyond the state shown in Figure 6.

[0041] Figure 7 is an explanatory diagram showing the correlation of data interpolation between the upper region 202 and the lower region 204, assuming that the entire visual field examination area of ​​the fundus is interpolated. In cases of visual field defects, significant differences may occur in the upper region 202 or the lower region 204. In such cases, if data interpolation is performed on examination points located in the upper region 202 and the lower region 204, the result of the interpolation will have a correlation between the upper region 202 and the lower region 204. In particular, in the correlation region 210 spanning the upper region 202 and the lower region 204, as shown in Figure 7, there is a risk that examination points that are actually appropriate for visual field sensitivity may be interpolated as points with poor visual field sensitivity.

[0042] In this embodiment, interpolation of the inspection data is performed independently in the upper region 202 and the lower region 204, thereby suppressing inappropriate interpolation due to correlation between the respective regions.

[0043] The visual field examination area is not only divided vertically by a horizontal meridian 206 passing through the fovea, as shown in Figure 5A, but as shown in Figure 8A, for example, the upper region 202 may be subdivided into regions 220, 222, 224, 226, 228, and 230, and the examination data may be interpolated independently in each region.

[0044] Furthermore, as shown in Figure 8B, it may be divided into two sections horizontally and horizontally by a vertical meridian 240 passing through the fovea. Alternatively, as shown in Figure 8C, it may be divided into four sections vertically and horizontally and horizontally by a horizontal meridian 206 passing through the fovea and a vertical meridian 240 passing through the fovea.

[0045] Figure 9 shows a flowchart of the visual field testing process executed by the CPU 22 of the visual field analyzer 110. The visual field testing process shown in the flowchart of Figure 9 is realized when the CPU 22 executes the visual field testing program. This visual field testing process starts when the operator presses a start button (not shown) displayed on the input / display unit 50.

[0046] In step 100, the image processing unit 74 displays a patient ID input screen on the input / display unit 50. The operator enters the patient ID into the input / display unit 50. In step 102, the processing unit 76 obtains the patient ID.

[0047] In step 104, the examination point setting unit 72 queries the server 140 to determine whether the visual field sensitivity test results corresponding to the acquired patient ID are stored. That is, it queries whether the visual field sensitivity test results corresponding to the acquired patient ID are stored. The examination point setting unit 72 obtains the query result from the server 140 and, based on the query result, determines whether or not there is past data for the visual field sensitivity test results corresponding to the patient ID. The past data is data for each subject and data corresponding to each subject's examination point. The past data may include, for example, the patient's visual field sensitivity, the estimated sensitivity of each examination point described later, the number of examinations, and the cumulative function. The past data may be data obtained from all examinations performed in the past, or it may be data updated after the most recent examination.

[0048] In step 104, if it is determined that there is past data of visual field sensitivity test results corresponding to the patient ID, in step 106, the processing unit 76 reads the latest estimated sensitivity (visual field sensitivity) and number of tests for each test point in the set of test points 200 from the past data corresponding to the entered patient ID. On the other hand, in step 104, if it is determined that there is no past data of visual field sensitivity test results corresponding to the patient ID, in step 108, the processing unit 76 reads a predetermined brightness value for each test point in the set of test points 200. The predetermined brightness value is, for example, a reference value for each test point in the set of test points 200 in a normal eye.

[0049] In step 110, the inspection point setting unit 72 sets an initial set of inspection points as shown in Figure 5A. Then, in step 112, the inspection point setting unit 72 selects the brightness value of the indicator light to be presented at the initial inspection points set in step 110. In step 112, the brightness value may be selected randomly, selected by the operator, or automatically selected based on past data.

[0050] Step 114 initializes the cumulative function. The cumulative function is a function that shows the relationship between the brightness value of the indicator light and the number of inspections. More specifically, it is a function that associates the cumulative number of inspections used with the brightness value of each indicator light. Initializing the cumulative function is the process of setting the number of inspections corresponding to each brightness value to zero, as shown in Figure 11A. The cumulative function will be described later using Figures 11A to 11I.

[0051] In step 116, one inspection point is selected from the set of initial inspection points set in step 110. This inspection point may be selected randomly from the set of initial inspection points, selected by the operator, or automatically selected based on past data.

[0052] In step 118, the cumulative number of inspections for the inspection points selected in step 116 is obtained. The cumulative number of inspections can be extracted using the cumulative function described later, but it may also be stored as data independent of the cumulative function.

[0053] Step 120 determines whether the cumulative number of tests is 1 or greater. If the cumulative number of tests is 1 or greater in Step 120, the procedure proceeds to Step 122; otherwise, the procedure proceeds to Step 124.

[0054] In step 122, an indicator light is presented to the inspection point selected in step 116 with a luminance value based on a cumulative function. The inspection point setting unit 72 sets the luminance value of the indicator light to be presented from a range of luminance values ​​extracted from the cumulative function. In the technology of this disclosure, the luminance value of the indicator light to be presented may be set by randomly selecting from the extracted range of luminance values, or by selecting an arbitrarily determined value. For example, the inspection point setting unit 72 may select the median value or 3 / 4 of the range as the luminance value of the indicator light to be presented from that range. Next, the inspection point setting unit 72 controls the projection device so that the indicator light is incident on the inspection point selected in step 116 with the extracted luminance value.

[0055] In step 124, the subject is presented with an indicator light representing the initial brightness value set in step 112.

[0056] In step 126, the test point setting unit 72 acquires the subject's response. If the subject recognizes the indicator light presented in step 122 or step 124, the subject turns on the switch of the response unit 60. This sends a recognition signal to the control device 10. If the subject does not recognize the indicator light even when it is presented, the subject does not turn on the switch of the response unit 60. The test point setting unit 72 determines whether the subject recognized the indicator light based on whether a recognition signal was transmitted before a predetermined time has elapsed since the indicator light was presented. For example, if a recognition signal is transmitted before a predetermined time has elapsed since the indicator light was presented, the test point setting unit 72 acquires the subject's response indicating that the subject recognized the indicator light. If a recognition signal is not transmitted even after the predetermined time has elapsed, the test point setting unit 72 acquires the subject's response indicating that the subject did not recognize the indicator light. The test point setting unit 72 stores the subject's response acquired in step 126 in the external storage device 40.

[0057] In step 128, the test point setting unit 72 updates the cumulative function. In this embodiment, the processes from step 116 to step 128 are repeated, and the cumulative function update process in step 128 is also repeated. The cumulative number of tests is also updated. By repeating the processes from step 116 to step 128, indicator lights with different brightness values ​​are presented multiple times to each test point belonging to the set of initial test points set in step 110, and the subject's response to each indicator light is obtained. Based on the subject's response to each presentation, the cumulative function corresponding to each test point is updated. A detailed explanation follows below.

[0058] In the absence of past data, the cumulative number of tests before the test is 0 for each luminance value, as shown in Figure 11A, and there is no cumulative function. In step 124, for example, an indicator light with an initial luminance value of 28 dB is presented to the subject. If the subject does not recognize the indicator light, the test point setting unit 72 increases the number of tests for each luminance value in the range defined by 28 dB as the boundary, i.e., the range of 28 dB or higher, by a predetermined amount, as shown in Figure 11B. For example, the predetermined amount to increase is 1. Therefore, as shown in Figure 11B, the number of tests for each luminance value in the range of 28 dB or higher is 1.

[0059] In Figure 11B, even though only a luminance value of 28 dB is presented, the number of tests for each luminance value in the range above 28 dB is set to 1 for the following reason: If the subject does not perceive the 28 dB indicator light, it is presumed that the subject will not perceive indicator light with a luminance value greater than 28 dB, i.e., light dimmer than the presented indicator light. Therefore, for this test point where a 28 dB indicator light was presented, it is presumed that the subject's response will indicate that they did not perceive indicator light with a luminance value greater than 28 dB. Thus, for luminance values ​​greater than 28 dB, the subject's response can be expected without actually conducting the test, so the test count is increased by 1, treating it as if the test had been performed. The predetermined amount of increase may vary depending on each luminance value. For example, if the subject does not perceive the 28dB indicator light, the number of tests may be increased by 1 for each brightness value in the range of 28dB to less than 32dB, by 2 for each brightness value in the range of 32dB to less than 36dB, and by 3 for each brightness value in the range of 36dB or more. This is equivalent to assuming that the subject will not perceive any of the simulated 32dB and 36dB indicator lights presented in addition to the 28dB indicator light, and increasing the number of tests for each brightness value by 1 for the three tests including the simulated tests.

[0060] In step 128, if the test count is 1, the cumulative function is updated as shown in Figure 11B.

[0061] In step 130, it is determined whether the visual field sensitivity can be estimated with sufficient accuracy for the set of test points selected in step 116. In this embodiment, as will be described later, it is determined whether the cumulative function draws a downward-convex linear shape as shown in Figure 11I, and whether the brightness of the indicator light that the subject was able to recognize can be estimated with sufficient accuracy. If the number of tests is 1, the cumulative function does not draw a downward-convex linear shape as shown in Figure 11B, and therefore the visual field sensitivity cannot be estimated with sufficient accuracy.

[0062] To estimate visual field sensitivity in step 130, for the test points selected in step 116 Then, indicator lights with different luminance values ​​are presented, and the subjects' responses are obtained. The cumulative function is updated according to the luminance values ​​of the presented indicator lights and the subjects' responses.

[0063] For example, if the results shown in Figure 11B are obtained, as shown in Figure 11C, it is unclear whether the range of luminance values ​​smaller than 28 dB can be recognized for the inspection point selected in step 116. Therefore, it is necessary to explore (inspect) whether the range of luminance values ​​smaller than 28 dB can be recognized.

[0064] Therefore, through the above repetition, in step 122, from the cumulative function (see Figure 11B), 16dB is extracted from the range of luminance values ​​where the number of tests is less than 1, as shown in Figure 11D, and an indicator light for a luminance value of 16dB is presented. Then, suppose the subject does not recognize the indicator light for a luminance value of 16dB. In this case, for the above reason, the test point setting unit 72 increases the number of tests for each luminance value in the range defined by 16dB (the range of 16dB or more) by a predetermined amount (for example, 1). Thus, as shown in Figure 11D, the cumulative function is updated so that the number of tests for luminance values ​​from 16dB to less than 28dB becomes 1, and the number of tests for luminance values ​​in the range of 28dB or more becomes 2. In this case, as shown in Figure 11E, it is necessary to search (test) whether or not the range of luminance values ​​smaller than 16dB can be recognized.

[0065] By repeating the process from step 120 to step 128 in this way, and updating the cumulative function as shown in Figures 11F, 11G, 11H, and 11I, the range of luminance values ​​that need to be searched (checked) is narrowed. As a result, upper and lower limits of the range of luminance values ​​that need to be searched (checked) are determined, and a downward-convex linear cumulative function can be created.

[0066] If the cumulative function of the test point selected in step 116 reaches the state shown in Figure 11I, then an indicator light with a brightness value of 12 dB is presented to the test point selected in step 116 to obtain the subject's response. However, if the cumulative function of the test point selected in step 116 is as shown in Figure 11I, the subject's visual field sensitivity at this test point is expected to be around 12 dB. In this way, it is determined whether the visual field sensitivity of the test point selected in step 116 can be estimated.

[0067] The examples described above using Figures 11A to 11I represent cases where there is no past data, as mentioned above. On the other hand, if it is determined in step 104 of Figure 9 that past data exists, then a cumulative function and an estimated visual field sensitivity exist for each examination point in the set of examination points 200 corresponding to the patient ID. In this case, when the process in step 104 of Figure 9 is executed, step 104 becomes a positive determination, and in step 122, either or both of the cumulative function and the estimated visual field sensitivity for each examination point in the set of examination points 200 from the past data are used. The method for selecting the brightness value of the index light to present is, for example, if the brightness value with the smallest cumulative function value is 32 dB and the estimated visual field sensitivity is 28 dB, then the average value of these, 30 dB, is presented.

[0068] Step 132 determines whether the criteria are met. The criteria in Step 132 is whether all of the initial inspection points set in Step 110 have been inspected. If all of the initial inspection points have been inspected in Step 132, the procedure proceeds to Step 134. If not all of the initial inspection points have been inspected, the procedure proceeds to Step 116, and the procedure from Step 116 to Step 130 is performed.

[0069] In step 134, the inspection data obtained in the steps up to step 132 is read. Then, in step 136, the inspection point setting unit 72 performs data interpolation to estimate the overall visual field sensitivity, that is, the visual field sensitivity (estimated brightness value) for each inspection point in the inspection point set 200, based on the cumulative function obtained for each inspection point in the inspection point set 200. As mentioned above, in this embodiment, data interpolation is performed independently in the upper region 202 and the lower region 204. Furthermore, if the visual field inspection area is divided into four sections as shown in Figure 8C, data interpolation is performed independently in each of the four divided sections based on the inspection results in each of the four divided sections.

[0070] In this embodiment, the inspection point setting unit 72 estimates the field of view sensitivity (estimated luminance value) for each inspection point in the set of inspection points 200, including the initial inspection point. The inspection point setting unit 72 uses a stochastic process to estimate the estimated luminance values ​​of uninspected points from the estimated luminance values ​​of each inspected point, and also estimates a confidence level representing the certainty of the estimated luminance values ​​of the uninspected points.

[0071] In this embodiment, the inspection point setting unit 72 numerically determines the estimated brightness value of the uninspected points. The stochastic process in this case is referred to as a "probability field." In this embodiment, the inspection point setting unit 72 uses the stochastic process or probability field to estimate the estimated brightness value of the uninspected points from the estimated brightness value of each inspected point, and uses the stochastic process or probability field to estimate the reliability of the estimated brightness value of the uninspected points.

[0072] In this embodiment, Gaussian process regression (GPR) is used as the stochastic process. However, the technology of this disclosure is not limited to Gaussian process regression as the stochastic process. Other examples of stochastic processes include t-process regression. As described above, in this embodiment, data interpolation using the stochastic process is performed independently, for example, in the upper region 202 and the lower region 204.

[0073] As described above, the confidence level is numerical data that represents the certainty of the estimated brightness value of the estimated untested point. Specifically, the confidence level is numerical data that shows the range of possible field sensitivity values ​​for the untested point, centered around the estimated brightness value of the estimated untested point.

[0074] Figure 10 shows a flowchart of the process for estimating and interpolating the overall visual field sensitivity of the test points in step 136 of Figure 9. As shown in Figure 10, in step 301, the test point setting unit 72 calculates the estimated luminance value for each tested point. Specifically, first, in order to calculate the estimated luminance value (visual field sensitivity) for each tested point, the test point setting unit 72 calculates the probability f of the test point of the optic nerve of the subject's eye 12 recognizing the indicator light for that luminance value, as shown in Figure 12. a,b A luminance value-correct answer rate curve showing the relationship (θ) is used. The luminance value-correct answer rate curve is defined by the following equation. In the following equation, θ is the luminance value used in each test at the test point.

[0075]

number

[0076] As shown below, a is a constant greater than 0, and b is a value contained in R (where R is the set of all real numbers).

[0077]

number

[0078] The test point setting unit 72 uses the equation shown in the curve above to determine the likelihood L(a,b) of each tested point from the following equation. More specifically, for example, if at a certain tested point the brightness value is 20 dB in the first test and the subject's response is recognized (Yes), the test point setting unit 72 calculates the probability f a,b(20) is used. In the second test, if the brightness value is 24 dB and the subject does not recognize the response (No), the test point setting unit 72 is set to (1-f a,b (24)) is used. In the third test, if the brightness value is 16 dB and the subject's response is recognized (Yes), the test point setting unit 72 sets probability f a,b (16) is used. For each inspected point, the inspection point setting unit 72 uses the product of the values ​​corresponding to all the inspection results as described above to find the value of b that maximizes the likelihood L(a,b).

[0079]

number

[0080] The value b obtained for each inspected point is used as the estimated luminance value for each inspected point. For example, at inspected point (x2), an estimated luminance value of 21 dB is calculated; at inspected point (x3), an estimated luminance value of 19.6 dB is calculated; and at inspected point (x5), an estimated luminance value of 31.5 dB is calculated.

[0081] In step 303, the inspection point setting unit 72 calculates the estimated brightness value for each uninspected point using Gaussian process regression. Specifically, for each uninspected point, the inspection point setting unit 72 calculates the estimated brightness value E[X(x*)|D] from the following formula using the estimated brightness value of each inspected point.

[0082]

number

[0083]

number

[0084]

number

[0085]

Number

[0086] k* of number 4 D and K of number 5 D K(x,x’) of is the following Gaussian RBF kernel (Radial basis function kernel). In the following formula, θ1 and θ2 are real numbers.

[0087]

Number

[0088] x of K(x, x') represents each x1, x2,...X N and each of x1, x2,...X N is the XY coordinate of the position of the inspected point.

[0089] x’ of K(x, x') is the XY coordinate of each uninspected point x*.

[0090] Y D y1, y2,...Y of N are the estimated luminance values of each inspected point.

[0091] u The estimated luminance value E[X(x*)|D] of each uninspected point obtained as above is the average value of the luminance values estimated from the estimated luminance values of each inspected point for each uninspected point.

[0092] In step 305, the inspection point setting unit 72 calculates the variance V[X(x*)|D] from the following formula as the reliability of the estimated luminance value of each uninspected point that has not been inspected, using Gaussian process regression.

[0093]

number

[0094] k ** The details are as follows:

[0095]

number

[0096] Once step 305 is completed, step 136 in Figure 9 is completed.

[0097] Figure 13 shows the relationship between the inspection points (including uninspected and inspected points) and the estimated luminance value of each inspection point. After the processing in step 136 of Figure 9 is completed, for example, as shown in Figure 13, the estimated luminance values ​​of each inspected point (x2, x3, x5, ...) are obtained, and the estimated luminance values ​​and their reliability for the uninspected points (x1, x4, x6, x7, x8, ...) are obtained. In Figure 13, the colored region around the curve indicates the range of error; a smaller width of the colored region indicates higher reliability of the estimated luminance value, while a larger width of the colored region indicates lower reliability of the estimated luminance value.

[0098] As shown in Figure 13, for example, the uninspected point (x4) is adjacent to the inspected points (x3, x5) and relatively close to them. However, the uninspected point (x8) is relatively far from the inspected point (x5). Therefore, the error range of the estimated brightness value for the uninspected point (x4) is relatively small and the confidence value is high, while the error range of the estimated brightness value for the uninspected point (x8) is relatively large and the confidence value is low.

[0099] In step 138, the inspection point setting unit 72 determines whether additional inspection is necessary. The determination of whether additional inspection is necessary is based on the error range of the estimated luminance value. In step 138, if there are inspection points among the inspection points for which the estimated luminance value has been calculated where the error range exceeds a predetermined range, it is determined that additional inspection is necessary. The predetermined range in step 138 is specifically determined through the estimated luminance value calculation test.

[0100] If step 138 determines that no further testing is required, the process ends; if additional testing is required, the procedure proceeds to step 140.

[0101] In step 140, the examination point setting unit 72 sets a set of additional examination points. In this embodiment, the subject's case is estimated based on the examination results of the initial examination points, and additional examination points are set according to the estimated case. The estimation of the case and the setting of additional examination points may be performed using a control device 10 that has been trained using, for example, an RNN (regressive neural network). In machine learning using an RNN, the examination results for each case are used as training data to train the control device 10.

[0102] Figure 14A is a schematic diagram showing an example of the test results for each test point when there are no abnormalities. If all of the initial test points indicated by rectangles in Figure 14A are normal, it is presumed that only a dark area 188 exists, corresponding to the optic nerve head 184, which is the blind spot 186 in the visual field sensitivity map shown in Figure 14B. Then, as shown in Figure 14C, an equal number of additional test points, indicated by pentagons, are set in the area with sparse initial test points in the upper region 202 and the area with sparse initial test points in the lower region 204.

[0103] Figure 15A is a schematic diagram showing examples of examination results for each examination point when the upper region 202 is perforated nasally. As shown in Figure 15A, if there are many points of poor visual field sensitivity indicated by triangles in the nasal region 202N of the upper region 202, there is a possibility of nasal perforation of the upper region 202.

[0104] Figure 15B is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 has a nasal perforation. If there is a possibility of a nasal perforation of the upper region 202 in step 140, it is estimated that the points of poor visual field sensitivity are distributed as shown in Figure 15B. Then, as shown in Figure 15C, the same number of additional examination points, indicated by pentagons, are set in the areas of the upper region 202 where the initial examination points are sparse and in the areas of the lower region 204 where the initial examination points are sparse.

[0105] Figure 16A is a schematic diagram showing examples of examination results for each examination point when the upper region 202 has a temporal wedge-shaped defect. As shown in Figure 16A, if there are prominent areas of poor visual field sensitivity indicated by triangles in the temporal region 202E of the upper region 202, there is a possibility of a temporal wedge-shaped defect in the upper region 202.

[0106] Figure 16B is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 has a temporal wedge defect. If there is a possibility of a temporal wedge defect in the upper region 202 in step 140, it is estimated that the points of poor visual field sensitivity are distributed as shown in Figure 16B. Then, as shown in Figure 16C, additional test points are set in the areas of the upper region 202 where the initial test points are sparse and in the areas of the lower region 204 where the initial test points are sparse, respectively. The test point setting unit 72 preferentially sets the additional test points, indicated by a pentagon, in the temporal region 202E of the upper region 202 where the disease is suspected.

[0107] Figure 17A is a schematic diagram showing examples of the test results for each test point in the case of a nasal staircase. As shown in Figure 17A, if there are prominent points of poor visual field sensitivity indicated by triangles in the nasal region 204N of the lower region 204, there is a possibility of a nasal staircase in the lower region 204.

[0108] Figure 17B is a schematic diagram showing an example of a visual field sensitivity map when the lower region 204 is a nasal step. If there is a possibility of a nasal step in the lower region 204 in step 140, it is estimated that the points of poor visual field sensitivity are distributed as shown in Figure 17B. Then, as shown in Figure 17C, additional test points, indicated by pentagons, are set in the areas of the upper region 202 and the lower region 204 where the initial test points are sparse. In addition to the nasal perforation, temporal wedge defect, and nasal step described above, other conditions such as arcuate scotoma, paracentral scotoma, horizontal hemianopsia-like visual field, and central residual visual field may also be judged, and additional test points may be set according to the judged condition.

[0109] In step 142, the inspection point setting unit 72 selects the brightness value of the indicator light to be presented at the additional inspection point set in step 140. In step 142, the brightness value may be selected randomly, selected by the operator, or automatically selected based on past data.

[0110] In step 144, one inspection point is selected from the set of additional inspection points set in step 140. The selected inspection point may be randomly chosen from the set of additional inspection points, selected by the operator, or automatically selected based on past data.

[0111] In step 146, the cumulative number of inspections for the inspection points selected in step 144 is obtained. The cumulative number of inspections can be extracted from the cumulative function described above, but it may also be stored as data independent of the cumulative function.

[0112] Step 148 determines whether the cumulative number of tests is 1 or greater. If the cumulative number of tests is 1 or greater in Step 148, the procedure proceeds to Step 150; otherwise, the procedure proceeds to Step 152.

[0113] In step 150, an indicator light is presented to the inspection point selected in step 144 with a luminance value based on a cumulative function. The inspection point setting unit 72 sets the luminance value of the indicator light to be presented from a range of luminance values ​​extracted from the cumulative function. In the technology of this disclosure, the luminance value of the indicator light to be presented may be set by randomly selecting from the extracted range of luminance values, or by selecting an arbitrarily determined value. For example, the inspection point setting unit 72 may select the median value or 3 / 4 of the range as the luminance value of the indicator light to be presented from that range. Next, the inspection point setting unit 72 controls the projection device so that the indicator light is incident on the inspection point selected in step 144 with the extracted luminance value.

[0114] In step 152, the subject is presented with an indicator light representing the initial brightness value set in step 142.

[0115] In step 154, the test point setting unit 72 acquires the subject's response. If the subject recognizes the indicator light presented in step 150 or step 152, the subject turns on the switch of the response unit 60. This sends a recognition signal to the control device 10. If the subject does not recognize the indicator light even when it is presented, the subject does not turn on the switch of the response unit 60. The test point setting unit 72 determines whether the subject recognized the indicator light based on whether a recognition signal was transmitted before a predetermined time has elapsed since the indicator light was presented. For example, if a recognition signal is transmitted before a predetermined time has elapsed since the indicator light was presented, the test point setting unit 72 acquires the subject's response indicating that the subject recognized the indicator light. If a recognition signal is not transmitted even after the predetermined time has elapsed, the test point setting unit 72 acquires the subject's response indicating that the subject did not recognize the indicator light. The test point setting unit 72 stores the subject's response acquired in step 154 ​​in the external storage device 40.

[0116] In step 156, the test point setting unit 72 updates the cumulative function. In this embodiment, the processes from step 144 to step 156 are repeated, and the cumulative function update process in step 156 is also repeated. The cumulative number of tests is also updated. By repeating the processes from step 144 to step 156, indicator lights with different brightness values ​​are presented multiple times to each test point belonging to the set of additional test points set in step 140, and the subject's response to each indicator light is obtained. Based on the subject's response to each presentation, the cumulative function corresponding to each test point is updated in the same manner as in step 128 described above.

[0117] In step 158, the inspection point setting unit 72 determines whether the field of view sensitivity of the inspection point selected in step 144 can be estimated with sufficient accuracy. In this embodiment, similar to step 130, the cumulative function draws a downward-convex linear shape as shown in Figure 11I, and it is determined whether the brightness of the indicator light that the subject was able to recognize can be estimated.

[0118] Step 160 determines whether the criteria are met. The criteria in Step 160 is whether all of the additional inspection points set in Step 140 have been inspected. If all of the additional inspection points have been inspected in Step 160, the procedure proceeds to Step 162, and the additional inspection points are... If not all tests have been performed, proceed to step 144 and follow the steps from step 144 to step 158.

[0119] In step 162, the inspection data obtained in the steps up to step 160 is read. Then, in step 164, the inspection point setting unit 72 performs data interpolation to estimate the overall field of view sensitivity, that is, the field of view sensitivity (estimated brightness value) for each inspection point in the inspection point set 200, based on the cumulative function obtained for each inspection point in the inspection point set 200, in the same manner as in step 136 above.

[0120] In step 166, the image processing unit 74 creates screen data to visualize the cumulative function of each inspected point and each additional inspected point if performed, the estimated brightness value of each inspected point in the entire set of inspected points, and the confidence level of the estimated brightness value of the uninspected points.

[0121] Specifically, the screen data includes, firstly, a graph showing the estimated brightness value of each inspection point in the entire set of inspection points, as shown in Figure 18A.

[0122] Secondly, as shown in Figure 18B, this graph shows the estimated luminance value for each test point in the entire set of test points, with the confidence level of the estimated luminance value at the untested points added, centered on the field of view sensitivity.

[0123] Thirdly, as shown in Figure 19, there is a visual field sensitivity map. The visual field sensitivity map is an example of a method for displaying the visual field sensitivity distribution. The visual field sensitivity map displays the distribution of visual field sensitivity data for multiple test points included in the set of test points. The visual field sensitivity map may be generated for the entire set of test points, or for a part of the set of test points. The visual field sensitivity map also includes confidence data. Specifically, as shown in Figure 19, the visual field sensitivity map 510M is screen data of a map where test points with visual field sensitivity less than a predetermined value (dB) are marked with an asterisk (*) on an image simulating the fundus of the eye under examination 12. The visual field sensitivity map 510M is also screen data that can display the range 510N of test points with a confidence level of or higher than a predetermined value using a dotted line. Alternatively, for example, among the test points in the entire set of test points, untested points may be displayed in a different color from the colors of tested points and additional test points, and the screen data may be able to display the confidence level of the estimated brightness value of the untested point when the cursor is located on an untested point.

[0124] As described above, in this embodiment, by updating the cumulative function for each inspection point in the set of inspection points 200, the range of luminance values ​​that need to be searched (inspected) is gradually narrowed, making it possible to complete the visual field test in a shorter time than when the luminance values ​​of the indicator light are set randomly. The effectiveness of this embodiment using the cumulative function will be explained below with reference to Figures 20A to 21C. In each of Figures 20A to 21C, the horizontal axis represents the number of inspections, and the vertical axis represents the difference between the correct sensitivity value and the estimated sensitivity. A value of 0 on the vertical axis means that there is no difference between the correct value and the estimated value, and that the accuracy of the estimated value is good.

[0125] Figures 20A to 20C show the number of tests required to ensure sufficient accuracy in the visual field test results when randomly selecting light intensity at three different points on the optic nerve of the fundus of the eye being examined. Figures 21A to 21C show the number of tests required to ensure sufficient accuracy when applying the method of this embodiment at three different points on the optic nerve of the fundus of the eye being examined.

[0126] When brightness values ​​are selected randomly (Figures 20A to 20C), 70 to 80 inspections are required, whereas when brightness values ​​are selected using the method of this embodiment (Figures 21A to 21C), 3 to 15 inspections are sufficient. Therefore, it can be seen that the method of this embodiment contributes to reducing the number of inspections.

[0127] In the case of a method that linearly interpolates the estimated brightness values ​​of untested points, as shown in Figure 22, the reliability of the interpolated values ​​is not considered. For example, in the case of a method that interpolates the estimated brightness values ​​of two untested points by connecting them with a straight line, or by using the spline method (interpolation using a polynomial), the reliability of the interpolated values ​​is not considered.

[0128] In contrast, in this embodiment, along with the estimated luminance value of the uninspected points, the reliability of the estimated luminance value is also estimated. Specifically, in Figure 23, the horizontal axis shows each inspection point, and the vertical axis shows the corresponding estimated luminance value for each inspection point. The dotted line represents the correct value, the solid line represents the estimated luminance value, and the reliability is shown as a width centered on the estimated luminance value. As shown in Figure 23, since the reliability is shown, this embodiment allows the operator to recognize the accuracy of the estimated luminance value.

[0129] In the embodiments described above, Gaussian regression is used as the stochastic process, and a Gaussian RBF kernel is used. In the technology of this disclosure, the stochastic process is not limited to Gaussian regression, and for example, the following polynomial kernel may be used. In the following equation, c is a real number and p is a positive integer.

[0130]

number

[0131] Alternatively, the following Matern kernel may be used. In the following equation, Kv is a modified Bessel function of the second kind, v is a real number, and Γ(v) is the gamma function.

[0132]

number

[0133] In step 136 of Figure 9 of this embodiment, the inspection point setting unit 72 estimates the estimated luminance value of the uninspected points and estimates the reliability of the estimated luminance value of the uninspected points. The technology of this disclosure is not limited thereto. The inspection point setting unit 72 may calculate the range of possible values ​​for the estimated luminance value of each uninspected point from the estimated luminance value of each inspected point, and calculate the value within the calculated range (for example, the middle value) as the estimated luminance value of each uninspected point.

[0134] Each of the above stochastic processes is the same for each test point in the entire set of test points, but the techniques of this disclosure are not limited thereto. For example, different stochastic processes may be used for a central region including the center of the fundus and for a peripheral region surrounding the central region.

[0135] Furthermore, while the untested points for which estimated luminance values ​​are interpolated are located within the range to which the indicator light reaches through the pupil of the eye 12 being examined, estimated luminance values ​​may also be estimated for points in areas adjacent to this range, i.e., points where the indicator light does not reach, i.e., where visual field testing is not possible.

[0136] The examples described above illustrate cases where visual field testing is implemented using computer-based software configurations, but the technology of this disclosure is not limited to these. For example, instead of a computer-based software configuration, image processing may be performed solely by hardware configurations such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application Specific Integrated Circuits). Alternatively, some of the image processing may be performed by a software configuration, and the remaining processing by a hardware configuration.

[0137] Thus, the technology disclosed herein includes cases in which visual field testing is performed using computer-based software and cases in which it is not, and therefore includes the following technologies.

[0138] (First technology) A processing unit that measures the sensitivity of a plurality of first inspection points included in the first subregion within a field of view divided into at least a first subregion and a second subregion, An inspection point setting unit performs a process of estimating the sensitivity of a plurality of second inspection points, which are inspection points other than the first inspection point and included in the first partial region, using the sensitivity of the plurality of first inspection points. A visual field testing device equipped with the following features.

[0139] (Second technology) The processing unit performs a processing step of measuring the sensitivity of a plurality of first inspection points included in the first sub-region within a field of view divided into at least a first sub-region and a second sub-region, The inspection point setting unit performs an estimation step of estimating the sensitivity of a plurality of second inspection points, which are inspection points other than the first inspection point and included in the first partial region, using the sensitivity of the plurality of first inspection points. A visual field testing method comprising the following features.

[0140] Based on the information disclosed above, the following technologies are proposed. (Third technology) A computer program product for visual field testing, The aforementioned computer program product includes a computer-readable storage medium that is not itself a temporary signal, The aforementioned computer-readable storage medium stores a program. The aforementioned program, On the computer, A step of measuring the sensitivity of a plurality of first inspection points included in the first subregion within a field of view divided into at least a first subregion and a second subregion, The process involves estimating the sensitivity of a plurality of second inspection points, which are inspection points other than the first inspection point and included in the first subregion, using the sensitivity of the plurality of first inspection points. A computer program product that executes a command.

[0141] The control device 10 is an example of a "computer program product" of the technology disclosed herein.

[0142] The visual field testing process described above is merely an example. Therefore, it goes without saying that unnecessary steps may be deleted, new steps added, or the order of processing changed, as long as it does not deviate from the main point. Furthermore, the technology disclosed herein includes a method for examining an eye, comprising the steps of: presenting light at multiple light intensities to test points set on the retina of the eye to detect the sensitivity of the retina at the test points; estimating the sensitivity of areas other than the test points based on the detected sensitivity at the test points; and evaluating the reliability of the estimated sensitivity.

[0143] All documents, patent applications, and technical standards described herein are incorporated by reference in the same manner as when each individual document, patent application, and technical standard is specifically and individually incorporated by reference.

[0144] Furthermore, the disclosure of Japanese Patent Application No. 2021-100268 is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

Claims

1. A visual field test method for examining the visual field sensitivity within the visual field range of the eye of the subject, The steps include presenting indicator lights with multiple different luminance values ​​at each of the multiple first inspection points within the field of view, The steps include obtaining a recognition signal from the subject in response to the indicator light to determine a plurality of measured brightness values ​​at each of the first inspection points, A step of determining a first estimated brightness value that is estimated to be perceived by the eye under examination at each of the first examination points based on the plurality of measured brightness values, The steps include determining the error range between the second estimated luminance value, which is the luminance value that the eye under examination is estimated to perceive at a plurality of second examination points different from the first examination points, based on the first estimated luminance value at the plurality of first examination points, and the second estimated luminance value, A visual field testing method that includes this.

2. The error range is calculated based on the distance between the first inspection point and the second inspection point. The visual field testing method according to claim 1.

3. If the error range is greater than a predetermined value, the second inspection point is designated as an additional inspection point. The visual field testing method according to claim 1.

4. The step of determining the measured luminance value involves determining the upper and lower limits of the luminance range of the indicator light to be presented at the first inspection point in the step of determining the measured luminance value, based on the luminance value of the indicator light previously presented at the first inspection point, and presenting an indicator light with a luminance value within the luminance range at the first inspection point in the step of determining the measured luminance value. The visual field testing method according to claim 1.

5. The upper and lower limits of the luminance range are determined by using a cumulative function that shows the relationship between the luminance value of the indicator light presented at the first inspection point in the past and the number of inspections. The visual field testing method according to claim 4.

6. The second estimated luminance value is calculated using a stochastic process. The visual field testing method according to claim 1.

7. The aforementioned stochastic process is a Gaussian process. The visual field testing method according to claim 6.

8. The steps are performed to determine the measured luminance value within the field of view, to divide the field of view into a plurality of sub-regions, and to determine the first estimated luminance value and the second estimated luminance value in each of the plurality of sub-regions. The visual field testing method according to claim 1.

9. Based on the luminance values ​​of the first estimated luminance value and the second estimated luminance value, a field of view sensitivity map of the field of view range is generated. The visual field testing method according to claim 1.

10. Dividing the field of view into the aforementioned multiple sub-regions includes dividing the field of view into four sections using horizontal and vertical meridians. The first sub-region is the region above the horizontal meridian and to the left of the vertical meridian. The second sub-region is the region below the horizontal meridian and to the right of the vertical meridian. The third sub-region is the region below the horizontal meridian and to the left of the vertical meridian. The fourth sub-region is the region below the horizontal meridian and to the right of the vertical meridian. In each of the first, second, third, and fourth subregions, the steps of determining the first estimated luminance value and the second estimated luminance value are performed, and a field of view sensitivity map of the field of view range is generated based on the respective luminance values ​​of the first and second estimated luminance values. The visual field testing method according to claim 8.

11. A visual field testing device equipped with a processor, which tests the visual field sensitivity within the visual field range of the eye of a subject, The aforementioned processor, The steps include presenting indicator lights with multiple different luminance values ​​at each of the multiple first inspection points within the field of view, The steps include obtaining a recognition signal from the subject in response to the indicator light to determine a plurality of measured brightness values ​​at each of the first inspection points, Based on the plurality of measured brightness values, the subject at each of the inspection points of the first inspection point The steps include: determining the first estimated brightness value that the eye is estimated to recognize, The steps include determining the error range between the second estimated luminance value, which is the luminance value that the eye under examination is estimated to perceive at a plurality of second examination points different from the first examination points, based on the first estimated luminance value at the plurality of first examination points, and the second estimated luminance value, A visual field testing device.

12. On the computer, The steps include presenting indicator lights with multiple different luminance values ​​at each of the multiple first test points within the visual field range of the eye of the subject, which is the eye of the subject, The steps include obtaining a recognition signal from the subject in response to the indicator light to determine a plurality of measured brightness values ​​at each of the first inspection points, A step of determining a first estimated brightness value that is estimated to be perceived by the eye under examination at each of the first examination points based on the plurality of measured brightness values, The steps include determining the error range between the second estimated luminance value, which is the luminance value that the eye under examination is estimated to perceive at a plurality of second examination points different from the first examination points, based on the first estimated luminance value at the plurality of first examination points, and the second estimated luminance value, A visual field testing program that performs this test.

13. The error range is calculated based on the distance between the first inspection point and the second inspection point. The visual field testing program according to claim 12.

14. If the error range is greater than a predetermined value, the second inspection point is designated as an additional inspection point. The visual field testing program according to claim 12.

15. The step of determining the measured luminance value involves determining the upper and lower limits of the luminance range of the indicator light to be presented at the first inspection point in the step of determining the measured luminance value, based on the luminance value of the indicator light previously presented at the first inspection point, and presenting an indicator light with a luminance value within the luminance range at the first inspection point in the step of determining the measured luminance value. The visual field testing program according to claim 12.

16. The second estimated luminance value is calculated using a stochastic process. The visual field testing program according to claim 12.

17. The aforementioned stochastic process is a Gaussian process. The visual field testing program according to claim 16.

18. The steps are performed to determine the measured luminance value in the field of view, to divide the field of view into a plurality of sub-regions, and to determine the first estimated luminance value and the second estimated luminance value in each of the plurality of sub-regions. The visual field testing program according to claim 12.

19. Dividing the field of view into the aforementioned multiple sub-regions includes dividing the field of view into four sections using horizontal and vertical meridians. The first sub-region is the region above the horizontal meridian and to the left of the vertical meridian. The second sub-region is the region below the horizontal meridian and to the right of the vertical meridian. The third sub-region is the region below the horizontal meridian and to the left of the vertical meridian. The fourth sub-region is the region below the horizontal meridian and to the right of the vertical meridian. The visual field inspection program according to claim 18, characterized in that, in each of the first, second, third, and fourth partial regions, the steps of determining the first estimated luminance value and the second estimated luminance value are performed, and a visual field sensitivity map of the visual field range is generated based on the sensitivity of the first estimated luminance value and the second estimated luminance value, respectively.

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