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

Abstract

Provided 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, the visual field testing method comprising: a step for measuring the sensitivity of a plurality of first test points included in the first partial region; and a step for estimating the sensitivity of a plurality of second test points included in the first partial region using the sensitivity of the plurality of first test points, the second test points being test points other than the first test points.

Description

[Technical field]

[0001] The technology of the present disclosure relates to a visual field testing method, a visual field testing device, and a visual field testing program. [Background technology]

[0002] Japanese Patent No. 5048284 discloses a visual field testing device that tests the sensitivity of the examinee's eye to light stimuli. A visual field testing device that does not impose a burden on the examinee is desired. Summary of the Invention

[0003] A visual field examination method according to a first aspect of the technology disclosed herein is a visual field examination method for examining a visual field range divided into at least a first partial region and a second partial region, and includes a step of measuring the sensitivity of a plurality of first examination points included in the first partial region, and a step of performing a process of estimating the sensitivity of a plurality of second examination points, which are examination points other than the first examination points and are included in the first partial region, using the sensitivities of the plurality of first examination points.

[0004] A second aspect of the technology disclosed herein is a visual field examination device that includes a processor and inspects 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 examination points included in the first partial region, and performing a process of estimating the sensitivity of a plurality of second examination points, which are examination points other than the first examination points and are included in the first partial region, using the sensitivities of the plurality of first examination points.

[0005] A program of a third aspect of the technology disclosed herein causes a computer to execute the steps of measuring the sensitivity of a plurality of first inspection points included in a first partial region in a field of view range divided into at least a first partial region and a second partial region, and performing a process of estimating the sensitivity of a plurality of second inspection points, which are inspection points other than the first inspection points and are included in the first partial region, using the sensitivities of the plurality of first inspection points. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a block diagram of an ophthalmology system 100. [Diagram 2] FIG. 2 is a block diagram showing the configuration of a perimeter 110. [Diagram 3] FIG. 2 is a functional block diagram of a CPU 22 of the perimeter 110. [Figure 4A] FIG. 2 is an explanatory diagram showing the structure of an eye 12 to be examined. [Figure 4B] 1 is an image of an area of ​​interest 190 in a normal fundus. [Figure 4C] 1 is a schematic diagram showing an inspection point set 200, which is a set of inspection points at which index light is presented in an inspection target area 190. FIG. [Figure 4D] 1 is a visual field sensitivity map showing the results of a visual field test on a normal fundus. [Figure 5A] FIG. 13 is an explanatory diagram showing setting of an initial inspection point from an inspection point set 200. [Figure 5B] FIG. 13 is an explanatory diagram showing the results of inspecting the initial inspection point. [Figure 5C] FIG. 13 is an explanatory diagram showing an example of a case where additional inspection points are set based on inspection results. [Figure 5D] FIG. 13 is an explanatory diagram showing a case where additional inspection points are set. [Figure 5E] 13 is an explanatory diagram for estimating visual field sensitivity at untested points indicated by white circles in a visual field test area based on test results. FIG. [Figure 6] FIG. 1 is a schematic diagram showing an example of a visual field sensitivity map of a diseased fundus. [Figure 7] 2 is an explanatory diagram showing the correlation of data interpolation in an upper region 202 and a lower region 204 when it is assumed that test data is interpolated over the entire visual field test region of the fundus. FIG. [Figure 8A] This is an explanatory diagram showing a case where the upper region 202 is divided into regions 220, 222, 224, 226, 228, and 230, and inspection data is interpolated independently for each region. [Figure 8B]This is a schematic diagram showing a visual field examination area divided into two halves, left and right, by a vertical meridian 240 passing through the fovea. [Figure 8C] This is a schematic diagram in which the visual field examination area is divided into four parts, top, bottom, left, and right, by a horizontal meridian 206 passing through the fovea and a vertical meridian 240 passing through the fovea. [Figure 9] 13 is a flowchart of a visual field examination process executed by a CPU 22 of the perimeter 110. [Figure 10] 10 is a flowchart of a process for estimating and interpolating visual field sensitivity across inspection points in step 136 of FIG. 9. [Figure 11A] FIG. 13 is a diagram illustrating an update process of a cumulative function. [Figure 11B] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11C] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11D] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11E] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11F] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11G] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11H] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 11I] FIG. 13 is another diagram showing the update process of the cumulative function. [Figure 12] 1 is an explanatory diagram showing a luminance value-correct answer rate curve showing the relationship between a luminance value and the probability fa,b(θ) that an inspection point on the optic nerve of the subject's eye 12 recognizes an index light of that luminance value. [Figure 13] 1 is a schematic diagram showing the relationship between inspection points (including uninspected points and inspected points) and the estimated luminance value of each inspection point; [Figure 14A] FIG. 11 is a schematic diagram showing an example of the inspection results of each inspection point when no abnormality is found. [Figure 14B] FIG. 2 is a schematic diagram showing an example of a visual field sensitivity map in the absence of abnormalities. [Figure 14C] FIG. 13 is a schematic diagram showing the setting of additional inspection points when no abnormality is found. [Figure 15A] FIG. 13 is a schematic diagram showing an example of the test results at each test point when the upper region 202 is pierced on the nose side. [Figure 15B] FIG. 2 is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 is nasal perforated. [Figure 15C] FIG. 13 is a schematic diagram showing the setting of additional inspection points when the upper region 202 is perforated on the nose side. [Figure 16A] FIG. 2 is a schematic diagram showing an example of the test results at each test point when the upper region 202 is a temporal wedge defect. [Figure 16B] FIG. 2 is a schematic diagram showing an example of a visual field sensitivity map in the case where the upper region 202 is a temporal wedge defect. [Figure 16C] FIG. 2 is a schematic diagram showing an example of setting additional test points when the upper region 202 is a temporal wedge defect. [Figure 17A] FIG. 2 is a schematic diagram showing an example of the inspection results at each inspection point when the lower region 204 is a nasal step. [Figure 17B] FIG. 2 is a schematic diagram showing an example of a visual field sensitivity map when the lower region 204 is a nasal step. [Figure 17C] FIG. 2 is a schematic diagram showing an example of setting additional inspection points when the lower region 204 is a nasal staircase. [Figure 18A] 11 is a graph showing estimated luminance values ​​for each inspection point in the entire set of inspection points. [Figure 18B] This is a graph in which confidence levels have been added to the graph of FIG. 18A. [Figure 19] FIG. 13 shows visual field sensitivity map 510M. [Figure 20A] FIG. 1 is a diagram showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in the conventional technology. [Figure 20B] FIG. 11 is another diagram showing the relationship between the number of tests and the difference between the correct value of sensitivity and the estimated sensitivity in the prior art. [Figure 20C] FIG. 11 is another diagram showing the relationship between the number of tests and the difference between the correct value of sensitivity and the estimated sensitivity in the prior art. [Figure 21A]FIG. 13 is a diagram showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in the present embodiment. [Figure 21B] FIG. 11 is another diagram showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in the present embodiment. [Figure 21C] FIG. 11 is another diagram showing the relationship between the number of tests and the difference between the correct sensitivity value and the estimated sensitivity in the present embodiment. [Figure 22] 11A and 11B are diagrams illustrating a method for interpolating estimated luminance values ​​of uninspected points. [Diagram 23] 10 is a graph showing estimated luminance values ​​and reliability values ​​obtained in the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the technology of the present disclosure will be described in detail with reference to the drawings.

[0008] The configuration of an ophthalmologic system 100 will be described with reference to Fig. 1. As shown in Fig. 1, the ophthalmologic system 100 includes a static visual field testing device (hereinafter referred to as a "perimeter") 110, a management server device (hereinafter referred to as a "server") 140, and an image display device (hereinafter referred to as a "viewer") 150.

[0009] The perimeter 110 is an example of the "visual field testing device" of the technology of the present disclosure.

[0010] The perimeter 110 is an instrument for testing the visual field sensitivity (brightness value) of the subject's eye, which will be described in detail later, and is used for diagnosing glaucoma, retinitis pigmentosa, and the like.

[0011] Here, visual field sensitivity refers to the intensity (luminance value: luminance (dB)) of the index light that reaches the test point to be tested on the optic nerve present in the retina of the test eye and is recognized by the test subject. Note that the greater the luminance value expressed in dB, the smaller the intensity of the index light that reaches the test point. In other words, the smaller the luminance value expressed in dB, the greater the intensity of the index light that reaches the test point. In other words, the greater the luminance value expressed in dB, the darker the index light is, and the smaller the luminance value expressed in dB, the brighter the index light is.

[0012] The server 140 stores the test results (estimated sensitivity, etc.) of the visual field sensitivity of the subject's eye by the perimeter 110 in association with the patient ID. The viewer 150 displays medical information such as the test results of the visual field sensitivity of the subject's eye acquired from the server 140.

[0013] The perimeter 110 , the server 140 , and the viewer 150 are connected to each other via a network 130 .

[0014] FIG. 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 vertical direction to the horizontal plane is defined as the "Y direction," and the direction connecting the center of the pupil of the anterior part of the subject's eye 12 and the center of the eyeball is defined as the "Z direction." Therefore, the X direction, Y direction, and Z direction are perpendicular to each other.

[0016] As shown in FIG. 2, the perimeter 110 includes a control device 10 , an index presenting unit 30 , an external storage device 40 , an input / display unit 50 , and a response unit 60 .

[0017] The control device 10 is equipped with a computer having a CPU (Central Processing Unit) 22, a ROM (Read-Only Memory) 24, a RAM (Random Access Memory) 26, and an input / output (I / O) port 28, which are interconnected by a bus 20. The ROM 24 stores a visual field examination program, which will be described later.

[0018] The CPU 22 is an example of a "processor" of the technology of the present disclosure. The processor executes a visual field testing program.

[0019] To the I / O port 28, an index presentation unit 30, an external storage device 40, a communication interface (I / F) 45, an input / display unit 50, and a response unit 60 are connected.

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

[0021] The response unit 60 includes a switch (not shown) operated by the subject (patient) and a transmission unit. When the subject recognizes the index light during a visual field test described below, the subject turns on the switch. When the switch is turned on, the transmission unit transmits a recognition signal to the control device 10 indicating that the subject has recognized the index light.

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

[0023] The indicator presentation unit 30 includes a dome 30D, the inner surface of which is a hemisphere and a reflecting surface, and a plurality of positions on the inner surface of the dome 30D. point The dome 30D is provided with a projection device (not shown) that presents an index (specifically, projects light) to the subject's eye 30D. Under the control of the control device 10 according to a visual field testing program for visual field testing described below, the projection device presents indices at different points (index presentation points) on the inner surface of the dome 30D with a time lag. The index presentation points correspond to the retina of the subject's eye. The index light from the index presentation points reaches an examination point on the retina of the subject's eye 12. As described above, the subject who recognizes the index light turns on a switch, and the transmission unit transmits a recognition signal to the control device 10.

[0024] In the technology of the present disclosure, the configuration of the index presenting unit 30 is not limited to a configuration including the dome 30D and a projection device. In the technology of the present disclosure, for example, a configuration in which a point on the inner surface of the dome 30D emits light by itself or a configuration in which index light is directly presented to an inspection point on the retina of the subject's eye 12 can be adopted as the configuration of the index presenting unit 30.

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

[0026] Fig. 3 shows a functional block diagram of the CPU 22 of the perimeter 110. Various functions realized by the CPU 22 of the perimeter 110 executing the visual field examination program will be described. The visual field examination program has an examination point setting function, an image processing function, and a processing function. By the CPU 22 executing 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 Fig. 3.

[0027] 4A is an explanatory diagram showing the structure of the subject's eye 12. The eyeball constituting the subject's eye 12 is roughly spherical and surrounded by the sclera 170. Inside the sclera 170 is the choroid 172, and inside the choroid 172 is the retina 174, and the inside of the eyeball covered by the retina 174 is filled with a gelatinous vitreous body 176.

[0028] The retina 174 has visual cells arranged in a planar shape, and the 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 through the optic nerve 182 to the brain.

[0029] The area of ​​the retina 174 where visual cells are densely arranged is the macula 178, 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 arranged there. In addition, the optic disc 184 is the area where the optic nerve 182 converges, so there are no visual cells there. As a result, the area on the retina 174 where the optic disc 184 is present becomes the blind spot 186.

[0030] In this embodiment, the visual field sensitivity of the subject's eye 12 is measured, and an area on the retina 174 of the fundus where visual cells are significantly arranged is set as an examination target area 190.

[0031] 4B is an image of a test area 190 in a normal fundus of a right eye. The horizontal line across the image is the horizontal meridian 206, which is the boundary between the upper area 202 and the lower area 204 in the visual field test area. In this embodiment, as described below, the test data is interpolated independently for each of the upper area 202 and the lower area 204 of the fundus.

[0032] FIG. 4C is a schematic diagram showing an inspection point set 200, which is a set of inspection points to which index light is presented in the inspection target area 190. Since there are many inspection points included in the inspection point set 200, in this embodiment, a thinning inspection is performed in which index light is presented to some selected inspection points to obtain the reaction of the subject, and the luminance value of the inspection point to which the index light is not presented is interpolated by a method such as Gaussian process regression. As will be described later, there are cases of fundus diseases in which the continuity is weak between the upper region 202 and the lower region 204. In addition, data interpolation such as Gaussian process regression is easily influenced by the data of the inspection point adjacent to the inspection point to be interpolated. Therefore, even if there is no disease in the upper region 202, if a disease is found in an inspection point in the lower region 204 adjacent to the upper region 202, if data interpolation is performed on the upper region 202 and the lower region 204 together, there is a risk that data of a normal inspection point will be interpolated as if it has a disease. In this embodiment, data interpolation is performed independently in the upper region 202 and the lower region 204, for example, to suppress the above-mentioned erroneous interpolation. Here, the term "cases" refers to cases of visual field defects due to glaucoma. Specifically, there are cases such as nasal perforation, nasal step, temporal wedge defect, and arcuate scotoma.

[0033] FIG. 4D is a visual field sensitivity map showing the results of a visual field test on a normal fundus of a right eye. In the visual field sensitivity map, areas with low luminance values, which indicate visual field sensitivity, are shown as dark areas. A dark area 188 is also present in FIG. 4D, but this dark area 188 corresponds to the optic disc 184, which is the blind spot 186.

[0034] 5A to 5E are explanatory diagrams showing an outline of visual field testing. In this embodiment, when visual field testing is started, initial test points shown in gray are set from a test point set 200 as shown in FIG. 5A. The test point set 200 is a set of test points that are each arranged over a range where index light reaches the optic nerve of the retina of the test eye 12 through the pupil of the test eye 12, for example, and are used to test visual field sensitivity. In this embodiment, some initial test points are set from the test point set 200, and a thinning test is performed to measure visual field sensitivity of test points with high priority, rather than all test points included in the test point set 200.

[0035] Basically, the initial test points are set regardless of whether or not there is past diagnostic data for the subject, but the initial test points may be set according to the subject's past diagnostic data. For example, if the past diagnostic data indicates the presence of an area with low visual field sensitivity, the initial test points may be set with a focus on the area including the area. In addition, the initial test points do not need to be set symmetrically above and below as in FIG. 5A, but may be set asymmetrically.

[0036] Fig. 5B is an explanatory diagram showing the results of testing the initial test points. In Fig. 5B, the test points shown with black triangles are points with poor visual field sensitivity where the visual field sensitivity is below a predetermined threshold, and the other test points shown with squares are points with good visual field sensitivity where the visual field sensitivity exceeds the predetermined threshold.

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

[0038] Fig. 5D is an explanatory diagram showing a case where additional test points are set. When additional test points are set, if the previously set additional test points were set preferentially in an area where many visual field sensitivity defects exist, the same number of additional test points shown as hexagons are set in the upper area 202 and the lower area 204 as shown in Fig. 5D. Alternatively, new additional test points may be set preferentially in an area where many visual field sensitivity defects exist.

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

[0040] 6 is a schematic diagram showing an example of a visual field sensitivity map of a diseased fundus. In the upper region 202 of the visual field sensitivity map, there is an area 208A indicating an upper visual field defect, and in the lower region 204, there is an area 208B indicating an inferior visual field defect. In FIG. 6, there is no significant continuity between the area 208A indicating the upper visual field defect and the area 208B indicating the inferior visual field defect. In such a situation, if data is interpolated over the entire test point set 200, there is a risk that the area 208A indicating the upper visual field defect will be enlarged more than in the state shown in FIG. 6.

[0041] 7 is an explanatory diagram showing the correlation of data interpolation in the upper region 202 and the lower region 204 when it is assumed that the test data is interpolated over the entire visual field test region of the fundus. In cases of visual field defect, a significant difference may occur in the upper region 202 or the lower region 204. In such cases, when data interpolation is performed on test points existing in the upper region 202 and the lower region 204, the result of the interpolation has a correlation with the upper region 202 and the lower region 204, and there is a risk that a test point that is originally a good visual field sensitivity point may be interpolated as a bad visual field sensitivity point in a correlation region 210 that straddles the upper region 202 and the lower region 204 as shown in FIG. 7 in particular.

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

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

[0044] Furthermore, as shown in Fig. 8B, it may be divided into two parts, left and right, by a vertical meridian 240 passing through the fovea, or as shown in Fig. 8C, it may be divided into four parts, up and down, left and right, by a horizontal meridian 206 passing through the fovea and a vertical meridian 240 passing through the fovea.

[0045] Fig. 9 shows a flowchart of visual field testing processing executed by the CPU 22 of the perimeter 110. The visual field testing processing shown in the flowchart of Fig. 9 is realized by the CPU 22 executing a visual field testing program. The visual field testing processing starts when an operator operates a start button (not shown) displayed on the input / display unit 50.

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

[0047] In step 104, the test point setting unit 72 inquires of the server 140 whether the test results of visual field sensitivity are stored corresponding to the acquired patient ID. That is, it inquires whether the test results of visual field sensitivity are stored corresponding to the acquired patient ID. The test point setting unit 72 acquires the inquiry result from the server 140, and determines whether there is past data of the test results of visual field sensitivity corresponding to the patient ID based on the acquired inquiry result. The past data is data for each subject and corresponding to the test points of each subject. The past data is, for example, the visual field sensitivity of the patient, the estimated sensitivity of each test point described later, the number of tests, and a cumulative function. The past data may be acquired data of all tests performed in the past, or may be data updated after the latest test.

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

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

[0050] In step 114, the accumulation function is initialized. The accumulation function is a function that indicates the relationship between the luminance value of the index light and the number of inspections, and more specifically, is a function that associates the accumulation number used in the inspection with each luminance value of the index light. The initialization of the accumulation function is a process that sets the number of inspections corresponding to each luminance value to zero, as shown in FIG. 11A. The accumulation function will be described later with reference to FIGS. 11A to 11I.

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

[0052] In step 118, the cumulative inspection count for the inspection point selected in step 116 is obtained. The cumulative inspection count can be extracted from a cumulative function, which will be described later, but may also be held as data independent of the cumulative function.

[0053] In step 120, it is determined whether the cumulative inspection number is equal to or greater than 1. In step 120, if the cumulative inspection number is equal to or greater than 1, the procedure proceeds to step 122, and if the cumulative inspection number is not equal to or greater than 1, the procedure proceeds to step .

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

[0055] In step 124, an index light having the initial luminance value set in step 112 is presented to the subject.

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

[0057] In step 128, the inspection point setting unit 72 updates the cumulative function. In this embodiment, the processes from step 116 to step 128 are repeated, and the update process of the cumulative function in step 128 is also repeated. times By repeating the processes from step 116 to step 128, index lights with different luminance values ​​are presented multiple times to each of the test points belonging to the set of initial test points set in step 110, and the subject's response to each index light is obtained, so that the cumulative function corresponding to each test point is updated based on the subject's response to each presentation. A specific description will be given below.

[0058] In the case where there is no past data, the cumulative number of tests before the test is 0 for each luminance value as shown in FIG. 11A, and no cumulative function exists. In the process of step 124, for example, an index light with an initial luminance value of 28 dB is presented to the subject. If the subject does not recognize the index light, the test point setting unit 72 increases the number of tests for each luminance value in the range determined with 28 dB as the boundary, that is, the range of 28 dB or more, by a predetermined amount as shown in FIG. 11B. The predetermined amount to be increased is, for example, 1. Therefore, as shown in FIG. 11B, the number of tests for each luminance value in the range of 28 dB or more becomes 1.

[0059] Here, in FIG. 11B, even though only a luminance value of 28 dB was presented, the number of tests for each luminance value in the range of 28 dB or more was set to 1 for the following reason. If the subject does not recognize the index light of 28 dB, it is presumed that the subject cannot recognize an index light with a luminance value greater than 28 dB, i.e., a light darker than the presented index light. Therefore, for this test point where an index light of 28 dB was presented, the index light with a luminance value greater than 28 dB was not recognized. light It is estimated that the subject's response is that he / she could not recognize even the luminance value of 28 dB. Therefore, for luminance values ​​greater than 28 dB, the subject's response is expected without the need for an actual test, and the number of tests is increased by one, assuming that the test has been performed. The predetermined amount of increase may be different depending on each luminance value. For example, if the subject does not recognize the 28 dB index light, the number of tests may be increased by one for each luminance value in the range of 28 dB or more and less than 32 dB, the number of tests may be increased by two for each luminance value in the range of 32 dB or more and less than 36 dB, and the number of tests may be increased by three for each luminance value in the range of 36 dB or more. This corresponds to an operation of increasing the number of tests by one for each of the above luminance values ​​for three tests including the pseudo test, assuming that the subject cannot recognize any of the luminance values ​​when a 32 dB index light and a 36 dB index light are presented in addition to the 28 dB index light.

[0060] In step 128, if the test number is 1, the accumulation function is updated as shown in FIG. 11B.

[0061] In step 130, in step 116 choice It is determined whether the visual field sensitivity can be estimated with sufficient accuracy for a set of test points that have been determined. In this embodiment, as described later, it is determined whether the cumulative function is a downward convex linear function as shown in FIG. 11I and the luminance of the index light that the subject recognized can be estimated with sufficient accuracy. When the number of tests is 1, the cumulative function is not a downward convex linear function as shown in FIG. 11B, so the visual field sensitivity cannot be estimated with sufficient accuracy.

[0062] Step 130: Visual Sensitivity Estimation To do this, index lights of different luminance values ​​are presented to the test points selected in step 116 to obtain the test subject's response, and the cumulative function is updated according to the luminance values ​​of the presented index lights and the test subject's response.

[0063] For example, when the result shown in FIG. 11B is obtained, as shown in FIG. 11C, since it is unclear whether the range of luminance values ​​smaller than 28 dB can be recognized for the inspection point selected in step 116, it is necessary to search (inspect) whether the range of luminance values ​​smaller than 28 dB can be recognized.

[0064] Therefore, in step 122, as shown in FIG. 11D, for example, 16 dB is extracted from the range of luminance values ​​in which the number of tests is less than 1 from the cumulative function (see FIG. 11B), and an index light with a luminance value of 16 dB is presented. Then, assume that the subject does not recognize the index light with a luminance value of 16 dB. 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 (range of 16 dB or more) determined with 16 dB as the boundary by a predetermined amount (for example, 1). Therefore, as shown in FIG. 11D, the cumulative function is updated so that the number of tests for luminance values ​​from 16 dB to less than 28 dB becomes 1, and the number of tests for luminance values ​​in the range of 28 dB or more becomes 2. In this case, as shown in FIG. 11E, it is necessary to search (test) whether or not the range of luminance values ​​smaller than 16 dB can be recognized.

[0065] In this way, by repeating the processes from step 120 to step 128 and updating the cumulative function as shown in Figures 11F, 11G, 11H, and 11I, the range of brightness values ​​that need to be searched (inspected) becomes narrower. As a result, the upper and lower limits of the range of brightness values ​​that need to be searched (inspected) are determined, and a cumulative function that is convex downward and linear can be created.

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

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

[0068] In step 132, it is determined whether or not the judgment condition is satisfied. The judgment condition in step 132 is whether or not 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, and if all of the initial inspection points have not been inspected, the procedure proceeds to step 116, and the procedures from step 116 to step 130 are performed.

[0069] In step 134, the inspection data obtained in the procedure 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, i.e., the visual field sensitivity (estimated luminance 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 described above, in this embodiment, data interpolation is performed independently for the upper region 202 and the lower region 204. Furthermore, when the visual field inspection region is divided into four as shown in FIG. 8C, data interpolation is performed independently for each of the four divided regions, based on the inspection result for each of the four divided regions.

[0070] In this embodiment, the inspection point setting unit 72 estimates the visual field sensitivity (estimated luminance value) for each inspection point in the inspection point set 200 including the initial inspection point. The inspection point setting unit 72 estimates the estimated luminance value of an uninspected point from the estimated luminance value of each inspected point using a stochastic process, and estimates a reliability indicating the likelihood of the estimated luminance value of the uninspected point.

[0071] In this embodiment, the inspection point setting unit 72 numerically determines the estimated luminance values ​​of uninspected points. The stochastic process in this case is called a "random field." In this embodiment, the inspection point setting unit 72 estimates the estimated luminance values ​​of uninspected points from the estimated luminance values ​​of each inspected point using the stochastic process or the random field, and estimates the reliability of the estimated luminance values ​​of uninspected points using the stochastic process or the random field.

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

[0073] As described above, the reliability is numerical data that indicates the likelihood of the estimated luminance value of the estimated uninspected point. Specifically, the reliability is numerical data that indicates the possible range of the visual field sensitivity of the uninspected point, centered on the estimated luminance value of the estimated uninspected point.

[0074] Fig. 10 shows a flowchart of the process of estimating and interpolating visual field sensitivity of all the inspection points in step 136 in Fig. 9. As shown in Fig. 10, in step 301, the inspection point setting unit 72 calculates an estimated luminance value of each inspected point. Specifically, in order to calculate the estimated luminance value (visual field sensitivity) of each inspected point, the inspection point setting unit 72 first calculates the probability f a,b A luminance value-correct answer rate curve showing the relationship between (θ) is used. The luminance value-correct answer rate curve is defined by the following formula. In the formula, 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 (R is the set of all real numbers).

[0077]

number

[0078] The inspection point setting unit 72 uses the equation representing the above curve to obtain the likelihood L(a,b) of each inspection point from the following equation. More specifically, for example, in the first inspection at a certain inspection point, if the luminance value is 20 dB and the subject's reaction is recognized (Yes), the inspection point setting unit 72 calculates the likelihood L(a,b) of each inspection point with a probability f a,b In the second test, if the luminance value is 24 dB and the subject's reaction is not recognized (No), the test point setting unit 72 uses (1-f a,bIn the third test, if the luminance value is 16 dB and the subject's reaction is recognized (Yes), the test point setting unit 72 uses the probability f a,b (16) is used. The inspection point setting unit 72 uses the product of the values ​​according to the results of all the inspections for each inspected point, and calculates the likelihood L Find b such that (a,b) is maximized.

[0079]

number

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

[0081] In step 303, the inspection point setting unit 72 calculates an estimated luminance value of each uninspected point that has not been inspected, using Gaussian process regression. Specifically, the inspection point setting unit 72 calculates an estimated luminance value E[X(x*)|D] for each uninspected point, using the estimated luminance values ​​of each inspected point, from the following formula:

[0082]

number

[0083]

number

[0084]

number

[0085]

number

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

[0087]

number

[0088] The x in K(x, x') is x1, x2, ...X N Denotes x1, x2, ... X N Each of these is the XY coordinate of the location of the inspected point.

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

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

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

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

[0093]

number

[0094] k ** is as follows:

[0095]

number

[0096] When the process of step 305 ends, the process of step 136 in FIG. 9 ends.

[0097] Fig. 13 is a diagram showing the relationship between inspection points (including uninspected points and inspected points) and the estimated luminance value of each inspection point. When the process of step 136 in Fig. 9 is completed, for example, as shown in Fig. 13, the estimated luminance value of each inspected point (x2, x3, x5, ...) is obtained, and the estimated luminance value and its reliability of uninspected points (x1, x4, x6, x7, x8, ...) are obtained. In Fig. 13, the colored area existing around the curve indicates the range of error, and the reliability of the estimated luminance value is high when the width of the colored area is small, and the reliability of the estimated luminance value is low when the width of the colored area is large.

[0098] 13, for example, an uninspected point (x4) is adjacent to inspected points (x3, x5) and is relatively close to the inspected points (x3, x5). However, an uninspected point (x8) is relatively far from the inspected point (x5). Therefore, the error range of the estimated luminance value of the uninspected point (x4) is relatively small and the reliability value is high, while the error range of the estimated luminance value of the uninspected point (x8) is relatively large and the reliability value is low.

[0099] In step 138, the inspection point setting unit 72 determines whether or not an additional inspection is necessary. The determination of whether or not an additional inspection is necessary is made based on the error range of the estimated brightness value. In step 138, if there is an inspection point whose error range exceeds a predetermined range among the inspection points for which an estimated brightness value has been calculated, it is determined that an additional inspection is necessary. The predetermined range in step 138 is specifically determined through testing of the estimated brightness value calculation.

[0100] If it is determined in step 138 that no additional testing is required, the process ends; if additional testing is required, the process 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 case of the subject is estimated based on the examination results of the initial examination points, and the additional examination points are set according to the estimated case. The estimation of the case and the setting of the additional examination points may be performed using the control device 10 that has undergone machine learning using, for example, an RNN (regression neural network) or the like. In machine learning using an RNN or the like, the examination results related to each case are used as training data to train the control device 10.

[0102] Fig. 14A is a schematic diagram showing an example of the test results of each test point when no abnormality is found. If all of the initial test points shown as squares in Fig. 14A are normal, it is estimated that only a dark area 188 corresponding to the optic disc 184, which is a blind spot 186, exists in the visual field sensitivity map shown in Fig. 14B. Then, as shown in Fig. 14C, the same number of additional test points shown as pentagons are set in the region where the initial test points are sparse in the upper region 202 and the region where the initial test points are sparse in the lower region 204.

[0103] Fig. 15A is a schematic diagram showing an example of the test results of each test point when the upper region 202 is perforated on the nasal side. As shown in Fig. 15A, when the visual field sensitivity defect point shown by the triangle in the nasal side region 202N of the upper region 202 is significant, there is a possibility of perforation on the nasal side of the upper region 202.

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

[0105] Fig. 16A is a schematic diagram showing an example of the test results of each test point when the upper region 202 has an ear-side wedge-shaped defect. As shown in Fig. 16A, when the visual field sensitivity defect point shown by the triangle in the ear-side region 202E of the upper region 202 is significant, there is a possibility of an ear-side wedge-shaped defect in the upper region 202.

[0106] 16B is a schematic diagram showing an example of a visual field sensitivity map when the upper region 202 has an temporal wedge-shaped defect. If there is a possibility of an temporal wedge-shaped defect in the upper region 202 in step 140, it is estimated that the visual field sensitivity defect points are distributed as shown in FIG. 16B. Then, as shown in FIG. 16C, additional test points are set in the region of the upper region 202 where the initial test points are sparse and in the region of the lower region 204 where the initial test points are sparse. However, the test point setting unit 72 does not set additional test points in the temporal region 20 of the upper region 202 where a disease is suspected. 2 An additional inspection point, indicated by a pentagon, is set preferentially at E.

[0107] 17A is a schematic diagram showing an example of the test results of each test point in the case of a nasal step. As shown in FIG. 17A, when the visual field sensitivity defect point shown by the triangle in the nasal region 204N of the lower region 204 is significant, there is a possibility of a nasal step in the lower region 204.

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

[0109] In step 142, the inspection point setting unit 72 selects a luminance value of the index light to be presented at the additional inspection point set in step 140. In step 142, the luminance value may be selected, for example, randomly, by the operator, or automatically 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 selected from the set of additional inspection points, may be selected by an operator, or may be automatically selected based on past data.

[0111] In step 146, the cumulative inspection count is obtained for the inspection point selected in step 144. The cumulative inspection count can be extracted from the above-mentioned accumulation function, but it may also be held as data independent of the accumulation function as the cumulative inspection count.

[0112] In step 148, it is determined whether the cumulative inspection number is equal to or greater than 1. In step 148, if the cumulative inspection number is equal to or greater than 1, the procedure proceeds to step 150, and if the cumulative inspection number is not equal to or greater than 1, the procedure proceeds to step 152.

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

[0114] In step 152, an index light having the initial luminance value set in step 142 is presented to the subject.

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

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

[0117] In step 158, the test point setting unit 72 determines whether the visual field sensitivity of the test point selected in step 144 can be estimated with sufficient accuracy. 11 Draw a downward convex line as shown in I, and judge whether the luminance of the index light recognized by the subject can be estimated.

[0118] In step 160, it is determined whether or not the judgment condition is satisfied. The judgment condition in step 160 is whether or not all the additional inspection points set in step 140 have been inspected. 160If all the additional inspection points have been inspected, the procedure proceeds to step 162, and if all the additional inspection points have not been inspected, the procedure proceeds to step 144, and the procedures from step 144 to step 158 are performed.

[0119] In step 162, the inspection data obtained in the procedure up to step 160 is read. Then, in step 164, the inspection point setting unit 72 performs data interpolation to estimate the overall visual field sensitivity, i.e., the visual field sensitivity (estimated luminance 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 described above.

[0120] In step 166, the image processing unit 74 creates screen data for visualizing the cumulative functions of each inspected point and each additional inspection point if performed, the estimated brightness value of each inspection point in the entire set of inspection points, and the reliability of the estimated brightness values ​​of uninspected points.

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

[0122] Secondly, as shown in FIG. 18B, a graph showing the estimated luminance value of each inspection point in the set of all inspection points is added with the reliability of the estimated luminance value at uninspected points, centered on the visual field sensitivity.

[0123] Third, as shown in FIG. 19, there is a visual field sensitivity map. The visual field sensitivity map is an example of a method of displaying visual field sensitivity distribution. The visual field sensitivity map displays the distribution of visual field sensitivity data of a plurality of inspection points included in a set of inspection points. The visual field sensitivity map may be generated for the entire set of inspection points, or may be generated for a portion of the set of inspection points. The visual field sensitivity map also includes reliability data. Specifically, as shown in FIG. 19, the visual field sensitivity map 510M is data of a map screen in which an image simulating the fundus of the subject's eye 12 is displayed with an asterisk (*) at inspection points whose visual field sensitivity is less than a predetermined value (dB). The visual field sensitivity map 510M also displays a range 510 of inspection points whose reliability is equal to or greater than a predetermined value. NIn addition, for example, among the inspection points in the set of all inspection points, uninspected points may be displayed in a color different from the colors of inspected points and additional inspection points, and, for example, when the cursor is positioned on an uninspected point, the reliability of the estimated brightness value of the uninspected point may be displayed.

[0124] As described above, in this embodiment, by updating the cumulative function for each inspection point in the inspection point set 200, the range of luminance values ​​that need to be searched (inspected) is gradually narrowed down, making it possible to complete the visual field inspection in a shorter time than in the case where the luminance value of the index light is set randomly. Hereinafter, the effectiveness of this embodiment using the cumulative function will be described with reference to Figs. 20A to 21C. In each of Figs. 20A to 21C, the horizontal axis indicates the number of inspections, and the vertical axis indicates the difference between the correct sensitivity value and the estimated sensitivity. 0 on the vertical axis means that there is no difference between the correct value and the estimated value, and 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 results of visual field testing when light intensities are randomly selected at three different points on the optic nerve of the fundus of the subject eye. Figures 21A to 21C show the number of tests required to ensure sufficient accuracy when the method of this embodiment is applied to three different points on the optic nerve of the fundus of the subject eye.

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

[0127] The reliability of the interpolated value is not taken into consideration in the case of a method of linearly interpolating estimated luminance values ​​of uninspected points as shown in Fig. 22. For example, in the case of a method of interpolating estimated luminance values ​​of two uninspected points by connecting them with a straight line or a spline method (interpolating using a polynomial), the reliability of the interpolated value is not taken into consideration.

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

[0129] In the above-described embodiment, Gaussian process regression is used as the stochastic process, and a Gaussian RBF kernel is used. In the technology disclosed herein, the stochastic process is not limited to Gaussian process 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 a gamma function.

[0132]

number

[0133] In step 136 of Fig. 9 in this embodiment, the inspection point setting unit 72 estimates an estimated luminance value of an uninspected point, and estimates the reliability of the estimated luminance value of the uninspected point. The technology of the present disclosure is not limited to this. The inspection point setting unit 72 may calculate a range of possible values ​​of the estimated luminance value of each uninspected point from the estimated luminance value of each inspected point, and calculate a value within the calculated range (e.g., a median value) as the estimated luminance value of each uninspected point.

[0134] Although the above-mentioned stochastic processes are the same for each of the examination points in the entire examination point set, the technique of the present disclosure is not limited to this. For example, different stochastic processes may be used for a central region of a predetermined range including the center of the fundus and a peripheral region around the central region.

[0135] In addition, the untested points for which estimated brightness values ​​are interpolated are located in the range where the index light reaches through the pupil of the test eye 12, but estimated brightness values ​​may also be estimated for points in the range adjacent to the range where the index light does not reach, i.e., points at positions where the visual field cannot be tested.

[0136] In each of the above-described examples, the visual field examination process is realized by a software configuration using a computer, but the technology of the present disclosure is not limited to this. For example, instead of a software configuration using a computer, image processing may be performed only by a hardware configuration such as a field-programmable gate array (FPGA) or an application specific integrated circuit (ASIC). A part of the image processing may be performed by a software configuration, and the remaining processing may be performed by a hardware configuration.

[0137] As such, the technology disclosed herein includes cases in which visual field testing processing is realized by a software configuration using a computer and cases in which it is not realized, and therefore includes the following technologies.

[0138] (First Technology) A processing unit that measures sensitivity of a plurality of first inspection points included in a first partial region in a field of view range divided into at least a first partial region and a second partial region; an inspection point setting unit that performs a process of estimating sensitivities of a plurality of second inspection points, which are inspection points other than the first inspection point and are included in the first partial region, using the sensitivities of the plurality of first inspection points; A visual field examination device comprising:

[0139] (Second Technology) A processing step in which the processing unit measures sensitivity of a plurality of first inspection points included in the first partial region in a field of view range divided into at least a first partial region and a second partial region; an estimation step in which an inspection point setting unit performs a process of estimating sensitivities of a plurality of second inspection points, which are inspection points other than the first inspection point and are included in the first partial region, using the sensitivities of the plurality of first inspection points; A visual field examination method comprising:

[0140] Based on the above disclosure, the following techniques are proposed. (Third Technology) 1. A computer program product for visual field testing, comprising: The computer program product comprises a computer-readable storage medium that is not itself a transitory signal; The computer-readable storage medium stores a program, The program is On the computer, Measuring the sensitivity of a plurality of first inspection points included in the first partial region in a field of view range divided into at least a first partial region and a second partial region; performing a process of estimating sensitivities of a plurality of second inspection points, which are inspection points other than the first inspection point and are included in the first partial region, using the sensitivities of the plurality of first inspection points; A computer program product that causes the

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

[0142] The visual field test process described above is merely an example. Therefore, it goes without saying that unnecessary steps may be deleted, new steps may be added, or the order of processing may be changed without departing from the scope of the present invention. In addition, the technology disclosed in this specification includes a method for testing an eye to be examined, which includes a step of presenting light with a plurality of light intensities to an examination point set on the retina of the eye to be examined, detecting the sensitivity of the examination point on the retina, estimating the sensitivity of a site other than the examination point based on the detected sensitivity of the examination point, and evaluating the reliability of the estimated sensitivity.

[0143] All publications, patent applications, and standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or standard was specifically and individually indicated to be incorporated by reference.

[0144] 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 document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A visual field testing method for testing visual field sensitivity in a visual field range of a subject's eye, comprising: presenting index lights of a plurality of different luminance values ​​at each of a plurality of first inspection points within the field of view; obtaining a measured luminance value at each of the first test points by acquiring a recognition signal from the subject in response to the index light; calculating a luminance value estimated to be recognized by the subject's eye at a second inspection point other than the first inspection point from the measured luminance value of each of the plurality of first inspection points to obtain a calculated luminance value; calculating an estimated luminance value, which is a luminance value that is estimated to be recognized by the subject's eye at the second inspection point, by calculating an average value of the calculated luminance values ​​calculated from each of the plurality of first inspection points; A visual field testing method comprising:

2. The step of determining the estimated luminance value includes calculating an error range of the estimated luminance value. The visual field examination method according to claim 1.

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

4. When the error range is greater than a predetermined value, the second inspection point is set as an additional inspection point. The visual field examination method according to claim 2.

5. The step of determining the measured luminance value includes determining upper and lower limits of a luminance range of the index light to be presented to the first inspection point in the step of determining the measured luminance value based on a luminance value of the index light previously presented at the first inspection point, and presenting an index light having a luminance value within the luminance range to the first inspection point in the step of determining the measured luminance value. The visual field examination method according to claim 1.

6. Determining the upper and lower limits of the luminance range includes determining the upper and lower limits of the luminance range using a cumulative function that indicates a relationship between the luminance values ​​of the index light previously presented at the first inspection point and the number of inspections. The visual field examination method according to claim 5.

7. The calculated luminance value is calculated using a stochastic process. The visual field examination method according to claim 1.

8. The stochastic process is a Gaussian process. The visual field examination method according to claim 7.

9. A step of determining the measured luminance value in the field of view range is performed, the field of view range is divided into a plurality of partial regions, and a step of determining the calculated luminance value and a step of determining the estimated luminance value are performed in each of the plurality of partial regions. The visual field examination method according to claim 1. generating a visual field sensitivity map for the visual field range based on each of the measured luminance values ​​and the estimated luminance values; The visual field examination method according to claim 1.

11. Dividing the field of view into a plurality of partial regions includes dividing the field of view into four parts by a horizontal meridian and a vertical meridian, a first sub-region is an area above the horizontal meridian and to the left of the vertical meridian; a second sub-region below the horizontal meridian and to the right of the vertical meridian; a third sub-region is an area below the horizontal meridian and to the left of the vertical meridian; a fourth sub-region is an area below the horizontal meridian and to the right of the vertical meridian; performing a step of determining the calculated luminance value and a step of determining the estimated luminance value in each of the first partial region, the second partial region, the third partial region, and the fourth partial region, and generating a visual field sensitivity map of the visual field range based on each of the measured luminance values ​​and the estimated luminance values. The visual field examination method according to claim 9.

12. The method includes estimating a case from the measured luminance value and the estimated luminance value.

2. The visual field examination method according to claim 1.

13. The method includes setting additional test points based on the estimated case. The visual field examination method according to claim 12.

14. The case is any one of nasal perforation, nasal step, temporal wedge defect, arcuate scotoma, paracentral scotoma, horizontal hemianopsia-like field, and central residual field. The visual field examination method according to claim 12.

15. A visual field testing device that includes a processor and tests visual field sensitivity in a visual field range of a subject's eye, the subject's eye, The processor, presenting index lights of a plurality of different luminance values ​​at each of a plurality of first inspection points within the field of view; obtaining a measured luminance value at each of the first test points by acquiring a recognition signal from the subject in response to the index light; Steps and calculating a luminance value estimated to be recognized by the subject's eye at a second inspection point other than the first inspection point from the measured luminance value of each of the plurality of first inspection points to obtain a calculated luminance value; calculating an estimated luminance value, which is a luminance value that is estimated to be recognized by the subject's eye at the second inspection point, by calculating an average value of the calculated luminance values ​​calculated from each of the plurality of first inspection points; A visual field testing device.

16. On the computer, A step of presenting index lights having a plurality of different luminance values ​​at each of a plurality of first test points within a visual field range of a subject's eye, which is the subject's eye; obtaining a measurement luminance value at each of the first test points by acquiring a recognition signal from the subject in response to the index light; calculating a luminance value estimated to be recognized by the subject's eye at a second inspection point other than the first inspection point from the measured luminance value of each of the plurality of first inspection points to obtain a calculated luminance value; calculating an estimated luminance value, which is a luminance value that is estimated to be recognized by the subject's eye at the second inspection point, by calculating an average value of the calculated luminance values ​​calculated from each of the plurality of first inspection points; A visual field testing program that performs the following:

17. The step of determining the estimated luminance value includes calculating an error range of the estimated luminance value. The visual field examination program according to claim 16.

18. The error range is calculated based on a distance between the first inspection point and the second inspection point. The visual field examination program according to claim 17.

19. When the error range is greater than a predetermined value, the second inspection point is set as an additional inspection point. The visual field examination program according to claim 17.

20. The step of determining the measured luminance value includes determining upper and lower limits of a luminance range of the index light to be presented to the first inspection point in the step of determining the measured luminance value based on a luminance value of the index light previously presented at the first inspection point, and presenting an index light having a luminance value within the luminance range to the first inspection point in the step of determining the measured luminance value. The visual field examination program according to claim 16.

21. The calculated luminance value is calculated using a stochastic process. The visual field examination program according to claim 16.

22. The stochastic process is a Gaussian process. The visual field examination program according to claim 21.

23. A step of determining the measured luminance value in the field of view range is performed, the field of view range is divided into a plurality of partial regions, and a step of determining a calculated luminance value and a step of determining the estimated luminance value are performed in each of the plurality of partial regions. The visual field examination program according to claim 16.

24. Dividing the field of view into a plurality of partial regions includes dividing the field of view into four parts by horizontal and vertical meridians, a first sub-region is an area above the horizontal meridian and to the left of the vertical meridian; a second sub-region below the horizontal meridian and to the right of the vertical meridian; a third sub-region is an area below the horizontal meridian and to the left of the vertical meridian; a fourth sub-region is an area below the horizontal meridian and to the right of the vertical meridian; The visual field examination program of claim 23, characterized in that a step of calculating the calculated brightness value and a step of calculating the estimated brightness value are performed in each of the first partial region, the second partial region, the third partial region, and the fourth partial region, and a visual field sensitivity map of the visual field range is generated based on the sensitivity of each of the measured brightness values ​​and the estimated brightness values.

Images