JP2011161122A - Visual field examination system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a visual field examination system objectively examining a visual field in a short time, considering the current situation. <P>SOLUTION: The visual field examination system includes a visual-field-position detection device 1 for detecting the visual-line-position of an examinee P and outputting its visual-line-position detection signal, a presentation device 2 for presenting (displaying) the examinee P with a fixation point (a) and a visual index (b) apart from the fixation point (a) at a prescribed interval, a control device 3 for controlling the presentation device 2 to present the fixation point (a) and the visual index (b), and a notification means 5 for notifying that the visual line of the examinee P does not reach the visual index (b) within a prescribed time. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a visual field inspection system for inspecting a visual field of a subject.

  In recent years, aging has increased eye diseases associated with aging. In particular, glaucoma, which is a major cause of blindness, is said to have a high prevalence of about 1 in 20 people over the age of 40 in Japan with approximately 2.2 million patients. Because glaucoma has few subjective symptoms, and when it turns out that glaucoma is found, the symptoms often progress considerably. Therefore, as a step before conducting a detailed examination, the person who has abnormal vision and the person who has no vision ( There is a need for a visual field inspection device for screening that can perform screening in a short time regardless of location.

  As a visual field inspection apparatus that is widely used in the current clinical field, there are a Goldman perimeter and a Humphrey perimeter. These perimeters are useful visual field inspection devices for determining the follow-up and treatment policy of glaucoma. The Goldman perimeter fixes the brightness and size of the target, moves from the periphery toward the center, obtains an isopter (isosensitivity curve), and evaluates the patient's visual field from the obtained isopter. Further, the Humphrey perimeter measures the visual field of the patient from the obtained luminance by fixing the target position of the target and changing the luminance to obtain the luminance at each measurement point. In order to inspect the visual field using these perimeters, (1) the doctor instructs the subject to keep an eye on the fixed point fixed in the visual field inspection device, and (2) the subject looks at the fixed point. In this state, the visual field inspection device presents the target around the fixation point, and (3) the subject presses the answer button of the visual inspection device when the target presented around the fixation point is seen. Answer, (4) The visual field inspection device records the answer from the subject, and (5) The visual field inspection device outputs information indicating the range of the visual field of the subject based on the answer recorded in the visual field inspection device. It is necessary to step on. With respect to the Humphrey perimeter, it is necessary to obtain the brightness value in a range before (1) to (5) and to estimate the brightness value of each inspection point therefrom. The inspection time by these perimeters takes about 10 to 20 minutes for one eye, and it is necessary to perform the inspection in a limited environment such as a dark room. Further, the inspection method is complicated, and there is a problem that it is difficult to inspect an infant or an elderly person who cannot understand the teaching. From these problems, it is considered that the conventional visual field inspection apparatus is not suitable for screening (see Patent Document 1 and Non-Patent Documents 1 and 2).

  The visual field inspection described above requires the subject's voluntary answer when showing the reaction of whether or not the target is visible. Therefore, it is a difficult test for infants and the elderly who cannot understand the teaching. In order to solve this problem, research has been conducted on a thunder visual field inspection device that does not require teaching and does not require the subject's independent response. For example, there is a method of observing eye movement when a target in a predetermined visual field range is presented to a subject with respect to a fixed viewpoint. This method is based on the principle (stereoscopic reflection) that an organism having a visual system moves its line of sight in the direction of the object when the object appears in the field of view. As means for observing this stereotaxic reflection, a method for detecting the direction of the line of sight using a template mapping method from a face image photographed by a CCD camera and a method for obtaining the information of the line of sight using a line-of-sight position detection device have been reported. Yes. If this method is used, it is possible to determine whether or not the target is recognized from the movement of the eye movement, so that it is not necessary to make a reply by pressing a button as in the conventional examination apparatus, and the examination is less complicated for the patient.

  However, there are two problems in using stereotactic reflection as a method for determining target detection. First, even if eye movement occurs, the amount of jumping of the generated eye movement is small, so that the eye movement is caused by stereotaxic reflection indicating that the target has been detected, or accidental eye movement (for example, fixed eye movement) It is difficult to determine whether it is a visual movement. For this reason, there is a risk that an erroneous result will be output, such as it is judged that an area that should not be seen by the subject is seen, and the test result may be unreliable It is cited as a point. In addition, it has been pointed out that the stereotaxic reflection is suppressed when the number of trials increases, and the movement itself may not occur. It has been reported that stereotaxic reflexes are less likely to occur when a target is presented in the peripheral visual field or when an adult is examined. From these facts, it has been reported that there is a limit to using stereotaxic reflection as a target detection judgment method when examining a wide field of view for subjects of a wide age group (Non-Patent Documents 3 to 3). 5).

  The retinal optic ganglion cell is composed of a large number of P cells that control small objects, color vision, visual acuity, and a small number of large M cells and K cells that recognize large objects and rapidly changing targets. Recent studies have revealed that optic ganglion cell degeneration in early glaucoma can be detected by M cells, and FDT perimeters targeting M cells have been developed. The FDT perimeter uses the fact that black and white striped patterns are alternately inverted at a frequency of 25 Hz, and the illusion phenomenon that the target is doubled occurs in normal M cells but does not occur in degenerated M cells. This is the principle of detecting visual field abnormalities, and is an apparatus suitable for screening that can inspect one eye in a time of about 30 seconds. However, even in a subject diagnosed as normal by FDT, there are cases where the Humphrey perimeter becomes abnormal, and the evaluation of measurement sensitivity and specificity has not been determined (see Non-Patent Document 6).

JP 2003-542 A

Japanese Visual Society, “Visual Information Processing Handbook”, Japan, Asakura Shoten, 2001, pp. 547-549 Shigeki Hashimoto, “Development of dynamic visual field measurement program using automatic perimeter”, Kinki University Medical Journal, Japan, Kinki University, November 25, 2003, Vol. 28, no. 3, pp. 207-221 Mikio Tsuji, Keito Tabata, Kei Nagata, Kotaro Tsuji, Kunihiro Chihara, “Development of a quantitative visual field measurement screening system for infants using an immersive presentation device (bioengineering)”, IEICE Transactions D-II, Japan, The Institute of Electronics, Information and Communication Engineers, September 1, 2005, Vol. J88, no. 9, pp. 1971-1978 Country Katago, Murakami Muneji, Fukushima Shogo, Fukunaga Hideo, Maeda Fumiatsu, Kani Kazutaka, Tanabe Akio, "Objective Pupil Field Measurement Technique Using Flat Panel Display", Biomedical Engineering: Journal of the Japan MEE Association, Japan, Japan Society for Medical and Biological Engineering, March 10, 2005, Vol. 43, no. 1, pp. 179-183 Norio Ideguchi, Yasushi Nakano, Kiyohiko Nunokawa, “Examination of saccade characteristics as a visual field measurement interface”, IEICE Technical Report WIT, Japan, The Institute of Electronics, Information and Communication Engineers, October 5, 2006, Volume 106, 285, pp. 45-50 Atsushi Nakano, "FDT (FDT Screener, Humphrey MATRIX), SWAP, MP-1 (Ophthalmic examination equipment useful for daily medical care and its usage)-(Vision, color vision, visual field)", Ophthalmology, Japan, Kanehara Publishing, September 2007, vol. 49, no. 1503-1512

  As a problem of the prior art, in the Goldman visual field inspection device or Humphrey visual field inspection device, since it is necessary to inspect each point precisely, the inspection time is long.

  In addition, the Tadami visual field inspection apparatus uses stereotaxic reflection as a method for determining whether or not a target has been detected. There are two problems in using stereotaxic reflection as a target detection method. First, even if eye movement occurs, the amount of jumping of the generated eye movement is so small that the eye movement is caused by stereotaxic reflection indicating that the target has been detected, or accidental eye movement (for example, fixation) It is difficult to determine whether it is fine movement). For this reason, there is a risk that an erroneous result will be output, such as it is judged that an area that should not be seen by the subject is seen, and the test result may be unreliable It is cited as a point. In addition, it has been pointed out that the stereotaxic reflection is suppressed when the number of trials increases, and the movement itself may not occur. It has been reported that stereotaxic reflexes are less likely to occur when a target is presented in the peripheral visual field or when an adult is examined. For these reasons, it has been reported that there is a limit to using stereotaxic reflection as a target detection judgment method when examining a wide field of view for subjects of a wide age group. Furthermore, the FDT visual field inspection apparatus is effective for normal-tension glaucoma because it targets only M cells, but has a drawback that it cannot evaluate the degeneration of other optic ganglion cells.

  This invention makes it a subject to provide the visual field inspection system which can test | inspect a visual field objectively in a short time in view of this situation.

  The visual field inspection system according to the present invention detects a visual line position of a subject and outputs a visual line position detection signal, and a visual point that is fixed to the visual point and a visual target that is separated from the visual point by a predetermined interval. In the visual field inspection system comprising a presentation device that is presented in a display area and a control device that controls the presentation device to present a fixation point and a visual target, the control device receives the line of sight received from the eye gaze position detection device. Determining means for determining whether or not the subject's line of sight has reached the target from a fixed viewpoint within a first reference time set in advance based on the position detection signal, and the determining means within the first reference time When it is determined that the subject's line of sight has reached the target from the fixed viewpoint, the reaction time required for one measurement in which the subject's line of sight reaches the target from the fixed viewpoint is stored for a plurality of times. Storage means and determination means When it is determined that the target has been reached, the fixation point presented on the presentation device is extinguished, the target presented on the presentation device is set as a new fixation point, and the inspection is performed with respect to the fixation point. A target position control means for presenting a new target at an arbitrary position of the target position, and when the number of times of measurement of the reaction time stored in the storage means reaches a predetermined number And a reference time calculation means for calculating a second reference time for determining whether or not the subject's line of sight has reached the target from the fixed viewpoint.

  According to this configuration, when the line of sight of the subject gazing at the fixation point moves from the fixation point and reaches the target, the determination unit of the control device determines the line of sight based on the line-of-sight position detection signal input from the line-of-sight position detection device. It is determined that the target has been reached from the fixation point, and the fixation point that has not been watched by the subject is eliminated. At this time, the target that the subject is gazing at becomes a new fixation point. The subject continues to watch the new fixation point until a new target is presented on the presentation device. The control device causes a new target to be examined for a new fixation point to be presented in the display area of the presentation device, and this is repeated until the targets are presented in all visual fields to be examined. Since the fixation point presentation position is not fixed in this way, the subject does not have to return the line of sight to the fixation point again when the line of sight reaches the target from the fixation point, and can objectively inspect the visual field in a short time.

  In addition, when a general subject visually recognizes the target, the time required to move the line of sight from the fixed viewpoint to the target is set as the first reference time. The means determines that the subject has not recognized the target and treats the visual field corresponding to the presented target as abnormal. Therefore, whether or not the subject can visually recognize the target can be determined based on whether the line of sight moves from the fixed viewpoint to the target within the first reference time. If the subject's line of sight does not reach the target from the fixed viewpoint within the first reference time, the target position control means can move to the inspection of another visual field to be inspected, and the inspection time can be shortened. .

  In addition to the first reference time, the visual field abnormality can be evaluated by the second reference time. Since the second reference time is calculated from the reaction time when each subject recognizes the target based on the determination result of the determination means, the second reference time is not affected by individual differences in the reaction time for each subject. It's time.

  Moreover, it is preferable that the control apparatus of the visual field inspection system according to the present invention further includes notification means for notifying that when the subject's line of sight does not reach the target within the first reference time. According to such a configuration, the subject knows that the visual target has already been presented on the presentation device by the notification by the notification means. The target position control means of the control device allows the subject to search for the target in order to move to the field of view to be examined next, move the line of sight to the target, and further shorten the inspection time.

  As described above, the visual field inspection system according to the present invention has an excellent effect that the visual field can be objectively inspected in a short time.

1 shows a schematic configuration diagram of a visual field inspection system according to an embodiment of the present invention. FIG. The block diagram of the visual field inspection system which concerns on the embodiment is shown. The control flow of the control apparatus of the visual field inspection system concerning the embodiment is shown. The control flow of the control apparatus of the visual field inspection system concerning the embodiment is shown. In the visual field inspection system according to the embodiment, an inspection procedure when the visual field of the subject is normal is shown. In the visual field inspection system according to the embodiment, an inspection procedure when the visual field of the subject is abnormal is shown. FIG. 4 is a graph of a subject's gaze movement in the visual field inspection system according to the embodiment, where (a) is a graph of a gaze movement of a subject with a normal visual field, and (b) is a graph of a gaze movement of a subject with a normal visual field. , Indicate. It is a graph of the elapsed time taken for a subject's gaze to move from a fixed viewpoint to a target in the visual field inspection system according to the embodiment, (a) is a graph of gaze movement of a subject with a normal visual field, (b ) Shows a graph of eye movement of a subject with an abnormal visual field. The graph of the position of the target shown in order to calculate the 2nd standard time in the visual field inspection system concerning the embodiment is shown. (A) shows a histogram of the reaction time of the subject A, (b) shows a histogram of the reaction time of the subject B, and (c) shows a histogram of the reaction time of the subject C. (A) shows a histogram of the reaction time of the subject D, and (b) shows a histogram of the reaction time of the subject E. The graph of the position of the target shown in the Example of the visual field inspection system concerning the embodiment is shown. (A) shows the test result of the subject A, and (b) shows the test result of the subject B. (A) shows the test result of the subject C, and (b) shows the test result of the subject E. (A) shows the test result of the subject F, and (b) shows the test result of the subject G. (A) shows the test result of subject H, (b) shows the test result of subject I. The test result of the subject J is shown.

  Hereinafter, an embodiment of a visual field inspection system according to the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the visual field inspection system according to the present embodiment detects a visual line position of a subject P and outputs a visual line position detection signal, a fixed visual point a, A presentation device 2 that presents (displays) a target b separated from the fixation point a by a predetermined interval to the subject P, and a control device that controls the presentation device 2 to present the fixation point a and the target b 3 and an informing means 5 for informing that when the line of sight of the subject P does not reach the target b within the (first) reference time.

  In this visual field inspection system, first, the fixation point a is presented to the presentation device 2, and the subject P gazes at the fixation point a. Next, the target b is presented to the presentation device 2, and it is inspected whether the subject P can visually recognize the target b. When the visual target b can be visually recognized, the visual line of the subject P moves from the fixed viewpoint a to the visual target b. When the subject P cannot visually recognize the target b, the timing of the subject P's line of sight not moving from the fixed viewpoint a or moving from the fixed viewpoint a to the target b is shifted. The line-of-sight position detection device 1 detects the line-of-sight position of the subject P. The control device 3 receives the eye gaze position detection signal from the eye gaze position detection device 1, and the subject P can visually recognize the eye b based on how the eye gaze of the subject P moves from the fixed viewpoint a to the eye b. It is determined whether or not. Thus, the visual field inspection system inspects the visual field of the subject P.

  Since the fixation point a and the target b are not visually displayed on the screen, they cannot be recognized by the subject P, but in order to suppress the influence of fixation disparity, 100 × 100 pixel gaze determination areas A and B (see FIG. 5 (a)).

  In the present embodiment, an example in which the visual field position detection device 1 is an eye camera will be described. The visual field position detection device 1 is connected to the control device 3. The visual field position detection device 1 outputs a line-of-sight position detection signal to the control device 3. The gaze position detection signal includes a signal related to the posture of the head of the subject P in addition to the gaze position of the subject P. When the posture of the head of the subject P is changed, the gaze position detection signal is presented to the presentation device 2 each time. The position of the fixed viewpoint a can be corrected.

  The presenting device 2 is provided with a substantially rectangular inspection display unit 21 that presents the fixation point a and the target b, and four corners of the inspection display unit 21 that clearly indicate the range of the inspection display unit 21. A marker 22 and a presentation device control device 23 that controls the examination display unit 21 are provided. The marker 22 is an illuminating device such as an LED or a light bulb that is connected to the control device 3 and lights when energized when starting visual field inspection. The markers 22 are not necessarily provided at the four corners, and may be provided at the four sides. The presentation device control device 23 is connected to the control device 3 and receives image data to be displayed on the examination display unit 21.

  The control device 3 includes a control unit 31 that controls the line-of-sight position detection device 1, the display device control device 23, and the notification unit 5, and a result display that is connected to the control unit 31 and displays a result of visual field inspection and the like. Display unit 32 and input means 33 connected to control unit 31 and capable of inputting and selecting necessary contents. The input means 33 is, for example, a keyboard or a mouse. The control device 3 may be connected to an output device for printing out visual field inspection results or the like, or to a LAN or the like so that visual field inspection result data can be transmitted to another computer.

  The control unit 31 includes a CPU 34 that executes a control program for controlling each device, a RAM 35 that stores an inspection result, and a ROM 36 that stores a control program for the visual field inspection system.

  The CPU 34 includes a processing unit that processes the control program and a number counter that counts the number of presentations and the like. The number counter is configured to add in increments of 0 to 1. This number counter is used in a first determination program, a second determination program, and the like, which will be described later.

  The RAM 35 includes a storage area for storing the target presentation sequence information that is information accompanying the examination for each target to be presented. The target presentation sequence information includes “target presentation position information P (j)”, “reaction time T (j)”, “abnormality determination count value r (j)”, “determination result” for each presentation count value j. R (j) ”can be stored in a one-dimensional array data structure.

  The presentation count value j is a value assigned to each target to be presented. The visual target presentation position information P (j) indicates the position of the visual target to be presented in polar coordinates, and is indicated by a radius and a declination around the fixed viewpoint. The reaction time T (j) is the time taken for the subject's line of sight to move from the fixed viewpoint to the target after the target is presented. The abnormality determination count value r (j) is a value indicating whether or not the subject can recognize the target position corresponding to the target presentation position information stored for each presentation count value j. In this embodiment, the reaction time is measured twice for one visual field region, and the reaction times measured twice are compared with different reference times, and the subject recognizes the target within each reference time. It is determined whether it has been completed. If it is determined that the reaction time exceeds the reference time, +1 is added. The abnormality determination count value r (j) is added up to 4. The determination result R (j) is a result of determining whether the subject can visually recognize the visual target based on the abnormality determination count value r (j). In the present embodiment, when the abnormality determination count value r (j) is two or more times for one visual field region, it is determined that the corresponding visual field region is not visually recognized. It is determined that the area is visible.

  The control program stored in the ROM 36 has the line of sight of the subject P within a first reference time (4 seconds in the present embodiment) set in advance based on the line-of-sight position detection signal received from the line-of-sight position detection device 1. The first determination main program (determination means) 37a for determining whether or not the target point a (0) has reached the target b (0) and the first determination main program 37a are within the first reference time. When the subject's line of sight is determined to have reached the target b (0) from the fixed viewpoint a (0), the visual line of the subject P is displayed from the fixed viewpoint a (0) after the target b (0) is presented. A first determination program 37 comprising a storage program (storage means) 37b for storing the reaction time required to reach the target b (0), and the eye of the subject P within the reference time from the fixation point a (0). It was determined that b (0) was not reached At this time, when the notification program 38 for controlling the notification means 5 to issue a warning sound and the first determination program 37 determine that the target b (0) has been reached, it is presented to the presentation device 2. In the display area where the fixation point a (0) is extinguished, the target b (0) presented on the presentation device 2 is set as a new fixation point a (1), and the fixation point a (1) is examined. When the reaction time stored in the target position control program (target position control means) 39 for presenting the new target b (1) at an arbitrary position of the storage program 37b reaches a predetermined number, Based on the reaction time, a reference time calculation program (reference time calculation means) 40 for calculating a second reference time for determining whether or not the gaze of the subject P has reached the target b from the fixation point a, and the reaction A second determination process for determining whether the time exceeds the second reference time. Gram 41, an abnormality determination program 42 for determining whether the visual field is normal based on the determination results of the first determination program 37 and the second determination program 41, and a determination result for displaying the determination result on the result display unit 32 A display program 43 is stored. Specific processing of these control programs will be described later.

  In the first determination program 37, the line of sight did not reach the target by the first reference time after the target was presented by the first determination main program 37a and the storage program 37b and the first determination main program 37a. In this case, a peripheral visual field addition program 37c for newly adding a visual field region to the examination target from the peripheral regions of the presented target region is provided. The first reference time used in the first determination main program 37a can be determined by a method to be described later, and is preset in the first determination main program 37a. The peripheral visual field addition program 37c, when the visual line does not reach the visual target by the first reference time after the visual target is presented by the first determination main program 37a, An additional visual target pattern including one or more peripheral visual field regions may be read, or a peripheral visual field region having a predetermined radius and declination may be added from the presented visual target position.

  The target position control program 39 includes a plurality of target presentation arrangement patterns in which target presentation arrangement information P (j) representing the position of the target presented to the presentation device is randomly arranged. The visual field presentation array pattern is a set of visual targets obtained by selecting a plurality of visual target presentation position information P (j) corresponding to the visual field region of the subject who needs to determine whether or not the visual recognition is possible. The target selected here does not necessarily need to be a set of different target presentation position information P (j), and two or more same target presentation position information P (j) may be included. . Each target presentation position information P (j) is determined twice in each target presentation presentation pattern according to the present embodiment so that all target presentation position information P (j) is determined twice. An example in which randomly arranged ones are used will be described. Each visual target presentation array pattern is a one-dimensional array arranged so that the order of the visual target presentation position information P (j) is different from other visual target presentation array patterns. The optotype presenting array pattern is used for the inspection such that a different pattern is selected for each inspection. Therefore, it becomes difficult for the subject to predict the target position to be presented next, and a more accurate examination is possible. This target presentation arrangement pattern may be displayed on the result display unit 32 so as to be selectable, and may be selected by operating the input means 33 by an operator who operates the visual field inspection system. Alternatively, the control unit 31 may automatically select a plurality of target presentation sequence patterns at random.

The second reference time used in the reference time calculation program 40 is obtained from the following calculation formula. Note that n is the number of targets (i = 0 to n−1). This calculation formula uses a normal distribution histogram to statistically calculate the frequency of the reaction time taken until the subject visually recognizes the visual target when the visual field is abnormal. It can be obtained by determining the coefficient so as to keep it low.

  The abnormality determination program 42 is totaled for each target presentation position information P (j) and the abnormality determination count value totaling program 42a for totaling the abnormality determination count value r (j) for each target presentation position information P (j). And an abnormality determination main program 42b for determining whether or not the abnormality determination count value r (j) is equal to or greater than a predetermined value.

  The abnormality determination count value totaling program 42a is used when determining twice or more for one target presentation position information P (j), and 1 for one target presentation position information P (j). If the determination is made once, it can be omitted.

  The abnormality determination main program 42b determines whether or not the subject can visually recognize the target based on whether or not the abnormality determination count value r (j) is equal to or greater than a predetermined value. In this embodiment, when the abnormality determination count value r (j) is two or more times, it is determined that the target is not visually recognized (abnormal determination), and when the abnormality determination count value r (j) is less than two times, the target is visually recognized (normal determination). ). In the present embodiment, an example in which the evaluation is performed by the abnormality determination and the normal determination is shown. However, the present invention is not limited to this, and a plurality of predetermined values may be provided and a plurality of determination results may be provided. For example, when the abnormality determination count value r (j) is less than 2, a normal determination may be made, and when it is 2 or more and less than 3, a determination of caution is required. The value added when the abnormality determination count value r (j) is greater than or equal to the first reference time and the value added when greater than or equal to the second reference time are weighted differently and added. May be. For example, +1 may be added when the time is equal to or longer than the first reference time, and +2 may be added when the time is equal to or longer than the second reference time.

  The notification unit 5 is a speaker that issues a warning sound when the subject P has not reached the target b at the first reference time. When the notification means 5 notifies the subject P, the subject P recognizes that the target b has already been presented. With this as a cue, the subject P moves his / her line of sight to the target b to force the target b to be recognized.

Next, the control flow of the visual field inspection system of the control unit will be described in detail with reference to FIGS.
(1) The CPU initializes the value i of the number counter (i = 0). The CPU presents the target presentation position information P (j), the reaction time T (j), the abnormality determination count value r (j), and the determination result R (j) for each presentation number count value j corresponding to the value i of the number counter. ) Are also initialized (S1).
(2) A target presentation arrangement pattern is selected (S2).
(3) When the target presentation arrangement pattern is selected, the CPU reads the selected target presentation arrangement pattern from the ROM. The CPU stores the target presentation position information P (j) from the read target presentation arrangement pattern in the RAM in correspondence with the number-of-presentation count value j in accordance with the arrangement order of each target presentation arrangement pattern. The CPU can read the target presentation position information for each presentation number count value j corresponding to this number count value i from the RAM by designating the number count value i.
(4) A fixed viewpoint is presented at the approximate center of the presentation device (S3).
(5) Gaze the subject's line of sight to a fixed viewpoint. That is, the subject is instructed by the operator to watch the fixation point for a predetermined time.
(6) After confirming that the subject keeps gazing at the fixation point for a predetermined time based on the sight line position detection signal from the sight line position detection device, the CPU selects a target to be examined with the fixation point as the origin. That is, the target presentation position information P () for each presentation count value j corresponding to the count count value i.
j) is read from the RAM. The CPU presents the selected target at a position based on the target presentation position information on the display area of the presentation device (S4).

(7) The elapsed time since the target is presented is measured, and the subject's line of sight has reached the target or gaze determination area by the first reference time (set to 4 seconds in the present embodiment). It is determined whether or not (S5).
(8) When step S5 is YES (when the visual line reaches the visual target or the gaze determination area within the first reference time after the visual target is presented), the CPU detects the visual line of the subject from the fixed viewpoint. The reaction time T (j) required to reach is stored in the RAM target presentation sequence information (S6).
(9) The CPU adds +1 to the value i of the number counter (S7).

(10) On the other hand, when step S5 is NO (when the line of sight does not reach the target or gaze determination area within the first reference time after the target is presented), the CPU sets the counter value i from the RAM. The abnormality determination counter value r (j) of the corresponding presentation count value j is read and added by +1 (S8).
(11) The CPU stores the reaction time T (j) required until the subject's line of sight reaches the target from the fixed viewpoint in the target presentation arrangement information in the RAM (S9).
(12) The CPU selects a new visual field area to be added to the inspection target from the peripheral areas in order to examine the peripheral area of the visual field area corresponding to the presentation number counter value j in more detail. The CPU adds the target presentation position information corresponding to the selected visual field region to the visual field presentation arrangement information by assigning a new target presentation count value j (S10). The number of visual field areas to be newly added is not limited to one, and may be two or more, and is appropriately selected.
(13) The CPU adds +1 to the value i of the number counter (S11).

(14) A warning sound is issued to cause the subject to recognize the target using the notification means (S12).
(15) It is determined whether or not the subject visually recognizes the target with the warning sound (S13).
(16) After step S7 or after YES in step S13, the fixation point is extinguished and the target is changed to a new fixation point (S14).

(17) It is determined whether or not the target based on all the target-presented sequence information is presented and determined (S15). Here, all the target presentation arrangement information is NO in step S5, and when the target presentation position information is newly added in step S11, the target presentation arrangement information after adding this target presentation position information. Means information.
(18) When step 15 is NO (when the target based on all the target presentation sequence information is not determined), the process returns to step S4 and the inspection is continued.

  (19) On the other hand, when step 15 is YES (when the target based on all the target presentation sequence information is determined), the CPU calculates the second reference time based on the target presentation sequence information stored in the RAM. (S16 in FIG. 6).

(20) The CPU initializes the value i of the number counter (i = 0) (S17).
(21) The CPU reads the reaction time T (j) of the target presentation sequence information for each presentation number count value j corresponding to the value i of the number counter. The CPU determines whether or not the reaction time T (j) exceeds the second reference time (S18).
(22) When step S18 is YES (when the reaction time T (j) exceeds the second reference time), the CPU reads the abnormality determination counter value r (j) corresponding to the number counter value i from the RAM. , +1 is added (S19).
(23) If NO in step S18 (when the reaction time T (j) is within the second reference time) or after step S19, the CPU adds +1 to the value i of the number counter (S20).
(24) It is determined whether or not it is determined whether or not the reaction time exceeds the second reference time for each presentation rotation count value j corresponding to all the target presentation sequence information (S21).
(25) When step S21 is NO (when it is not determined whether or not the reaction time exceeds the second reference time for each presentation rotation count value j corresponding to all the target presentation sequence information), step S18 Return to, and the determination is continued.

(26) On the other hand, when step S21 is YES (when it is determined whether or not the reaction time exceeds the second reference time for each presentation rotation count value j corresponding to all the target presentation sequence information), the CPU Then, the abnormality determination count value r (j) is read for each target presentation position information (S22).
(27) The CPU adds up the abnormality determination count value r (j) for each target presentation position information P (j) and stores it in the RAM (S23).

(28) The CPU reads the abnormality determination count value r (j) added up for each target presentation position information P (j) from the RAM, and whether or not the abnormality determination counter value r (j) is counted twice or more. Is determined (S24).
(29) When NO in step 24 (when the abnormality determination count value r (j) is less than twice), the CPU corresponds to visual field presentation position information corresponding to the abnormality determination count value r (j) less than twice. The visual field region to be determined is normal visual field, and the result that the visual field is normal is stored in the array result R (j) of the target presentation sequence information (S25).
(30) If YES in step 24 (when the abnormality determination count value r (j) is two or more times), the CPU corresponds to visual field presentation position information corresponding to the abnormality determination count value r (j) of two or more times. The visual field region to be determined is abnormal visual field, and the result that the visual field is abnormal is stored in the array result R (i) of the target presentation sequence information (S26).

(31) It is determined whether or not the visual field region corresponding to all the target presentation position information has been determined (S27).
(32) When step S27 is NO (when the visual field region corresponding to all the target presentation position information is not determined), the process returns to step S24 and the determination is continued.
(33) When step S27 is YES (when the visual field region corresponding to all the target presentation position information is determined), the CPU displays the determination result R (j) on the determination result display unit (S28). The inspection is complete.

  In this control flow, the control of steps S1 to S4 and S13 to S15 is processed by the visual field position control program 39, the control of steps S5 to S11 is processed by the first determination program 37, and the control of step S12 is performed by the notification program 38. The control of step S16 is processed by the reference time calculation program 40, the control of steps S17 to S21 is processed by the second determination program 41, the control of steps S22 to S27 is processed by the abnormality determination program 42, and the determination result The control of step S28 is processed by the display program 43. The first determination program 37 is controlled by steps S5, S7, S8, and S10 by the first determination main program 37a, by steps S6 and S9 by the storage program 37b, and by the peripheral vision addition program 37c. The control in step S11 is processed. As for the control of the abnormality determination program 42, the control of steps S22 and S23 is processed by the abnormality determination count value totaling program 42a, and the control of steps S24 to S27 is processed by the abnormality determination main program 42b.

  The visual field inspection used in the present invention is an eye movement measurement type visual field inspection using the gaze position detection device 1. That is, the subject's voluntary eye movement is used as a method for determining whether or not the target has been detected.

  The procedure of visual field inspection by this visual field inspection system is as follows (see FIG. 5). FIG. 5 is a diagram showing an inspection procedure of the visual field inspection system. (A), (c), (e), and (g) show the movement (position) of the visual target to be presented on the display device. (B), (d), (f), and (h) show the visual field regions inspected at the time of (a), (c), (e), and (g), respectively. .

  (1) The subject gazes at the fixation point a0 presented on the presentation device. When the subject gazes at the fixed viewpoint a0 for a certain period of time, the visual target b0 is presented within a predetermined field of view (see FIG. 5A). At this time, the visual field region of the subject corresponding to the target b0 is the position c0 shown in FIG. The visual target b0 is presented so that the positional relationship between the center O of the visual field and the visual field region c0 matches the positional relationship with the fixed viewpoint a0. (2) If the test subject can visually recognize the target b0 presented in a state in which the fixation point a0 is watched, the subject moves his line of sight to the position where the target b0 is presented. The motion trajectory t moves with the shortest distance from the fixed viewpoint a0 to the target b0 (see FIGS. 5C and 5D). (3) When the subject moves his / her line of sight to the presented target b0, the previous target b0 to which the line of sight has been transferred becomes a new fixation point a1, and the original fixation point a0 disappears (FIGS. 5E and 5F). )reference). (4) Maintain the state of gazing at the new fixation point a1, and return to the procedure (1). The test subject repeatedly moves the visual target and the line of sight in the steps (1) to (4) (see FIGS. 5G and 5H).

  When the visual target b cannot be visually recognized (see FIG. 6), it is considered that the visual target b is out of the field of view for the subject. At that time, the test subject cannot recognize the appearance of the target b, and the gaze movement trajectory t is meandering, or the gaze movement trajectory t is meandering. Is not visible, but indicates that the target b is presented. When the test subject is informed by the warning sound that the target cannot be recognized, the subject moves his / her line of sight to search for the target b, and when he finds the target b, he quickly adjusts his / her line of sight to the target b. If the target b is continuously watched for 1000 ms, the inspection is resumed by setting the target b as the new fixation point a.

  In this method, the visual field region is determined by repeating these procedures. At that time, a global inspection is performed from the peripheral visual field to the central visual field, and a point in which an abnormality is suspected is examined in detail and exploratory. It is considered that the time required for visual field inspection can be shortened by taking such an exploratory inspection method.

  Next, the line-of-sight data from the fixed viewpoint to the presentation target is shown in FIGS. FIGS. 7 (a) and 8 (a) show an example of an eye movement trajectory when the eye movement has occurred normally, and FIGS. 7 (b) and 8 (b) consider that an abnormality occurred in the eye movement trajectory. It is an example of data to be generated. The data shown in FIGS. 8A and 8B are for extracting a part of the line-of-sight data measured by the above procedure. FIG. 8A shows an example from the time when the measurement is started (elapsed time 0 msec) and the elapsed time when the target b is presented is about 2000 msec to the time when the visual line subsequently reaches the target b is about 3200 msec. Show. FIG. 8B is an example in which the line of sight has reached the target b at a time point of about 27000 msec after the time point when the target b is presented from the start of measurement.

  The eye movement trajectory t when the target b is presented at a position where the target b can be visually recognized reliably moves the line of sight to the position presented by one eye movement (see FIG. 7A). When the target b is presented at a position where it is ambiguous whether or not the target b is visible, the line of sight does not reach the position of the target b presented by one eye movement, and is presented from the fixed viewpoint a. An eye movement trajectory t was observed in which gaze occurred on x for about 200 msec until the target b, and then the line of sight moved to the position of the presented target b (see FIG. 7B).

  When the target b is presented at a position where the target b can be surely viewed with respect to the reaction time from the fixed viewpoint a toward the presentation target b, the target b is presented at about 2000 msec, and thereafter The line of sight has reached the target b at the time when about 1200 msec has elapsed (see FIG. 8A). On the other hand, when the target b is presented at a position where it is ambiguous whether the target b can be visually recognized, the target b is presented at about 24500 msec, and then the fixed point a after about 2000 msec has elapsed. The line of sight arrived at x from the point of view to the presentation target b, and the line of sight arrived at the target b when about 3500 msec passed (see FIG. 8B).

  It is considered that a quantitative evaluation can be made as to whether or not there is a visual field defect at the presented target position due to the difference in eye movement as described above.

  Although the target b0 is originally presented in an area where the target b0 cannot be recognized because it is in the abnormal area, the target is accidentally recognized during the examination process due to fixation movement or blinking. In some cases, pseudo eye movement may occur.

  Differences between such unnatural eye movements and intentional eye movements when a target can be recognized in the visual field region are considered to appear in the reaction time and movement trajectory.

  The invention of the present application uses the reaction time and movement trajectory until the line of sight is moved from the fixed viewpoint to the position of the target presented in order to separate the eye movement toward the intentional target from the eye movement that is not so, and the present invention. It can be verified that this method can detect the visual field region appropriately.

  Next, as a method of calculating the time for the subject to move his / her line of sight to the target presented in the visual field visible from the fixed viewpoint, the target is presented in eight directions with the fixed viewpoint as the origin, and from the fixed viewpoint at that time A method for measuring the reaction time until the line of sight is moved to the position of the presented target will be described. The subjects were healthy adult male college students (22-24 years old, wearing soft contacts). The visual target is a red visual target having a radius of about 2.2 mm, and the viewing angle is about 0.6 degrees.

  The measurement procedure is as follows. (1) The test subject covers the eye opposite to the test eye (right eye) with the eye patch. (2) The subject wears the head camera unit of the line-of-sight position detection device at a position of about 400 mm from the display and sits on a chair. Then, the head is fixed in a state where the center of the display area is in front of the examination eye. (3) The measurer performs calibration and validation processing in order to associate the actual gaze position with the gaze position detected by the apparatus. (4) The measurer presents a measurement screen to the subject. (5) The subject gazes at the fixation point presented on the initial screen. If the visual target presented in the horizontal / vertical direction and the oblique direction can be visually recognized with the fixed viewpoint as the origin, the line of sight is moved in that direction / position. If you can't see anything, keep an eye on the fixed point. (6) When the line of sight remains for a fixed time with respect to the fixed viewpoint, it is assumed that the subject cannot recognize the target, and the subject is informed by the warning sound that the target is not visible. (7) When the warning sound is heard, the subject moves the line of sight for the target search. (8) After all trials are completed, the measurer closes the measurement screen. Note that the measurement procedures (6) and (7) are procedures when the target is not recognized.

  The visual target presentation positions were 16 points in the horizontal direction of 10 °, 20 °, the vertical direction of 10 °, 20 °, and the diagonal direction of 10 °, 20 °, which is a place that can be surely seen by the subject. The number of target presentations was such that the target was presented five times at each position so that the total number of trials was 80 times. The time required to complete all trials was about 4 minutes.

  In order to investigate whether the reaction time varies depending on the number of trials and the variation in the reaction time, 4 times of trials 1 to 20, 21 to 40, 41 to 60, 61 to 80 times are examined. For each category, the average value and standard deviation of the reaction time were calculated for each subject.

  In addition, in order to compare eye movements that indicate target recognition with those that do not, eye movements when the target was presented at the Marriott blind spot were examined as a preliminary experiment.

  Table 1 shows the average and standard deviation of reaction times (number of trials 1 to 20, 21 to 40, 41 to 60, and 61 to 80 times) for each subject.

  From Table 1, for all subjects, there was no difference in the average value of the reaction time after the trial for four categories of trial order 1 to 20, 21 to 40, 41 to 60, 61 to 80 times. In other words, within the current measurement range, it is considered that the reaction time does not increase due to fatigue or the like as the number of trials increases. As for the standard deviation, when all the subjects were seen, there was no tendency for the standard deviation to increase or decrease as the number of trials increased. As described above, in the visual field inspection system of the present invention, the number of trials is within the examination time range of about 4 to 5 minutes in terms of time, but eye movement occurs with a constant reaction time regardless of the number of trials. I found out that

  In order to examine whether the method of the present invention is effective, it is an important factor whether or not the optional eye movement can be accurately extracted, and as a result of examining the tendency of the reaction time, regardless of the number of subjects and trials, The reaction time was within 2 seconds, and the standard deviation of the reaction time between trials was about ± 0.1 seconds for each subject. As a result of comparison with the eye movement when the target was presented to the Marriott blind spot, if the eye movement occurred when the presence of the target was detected for some reason, the reaction time required about 10 seconds. Even if the standard deviation value obtained from the above experiment is taken into account, "the condition that the target can be seen" and "the condition that the target that is supposed to be unseen can be seen due to the effect of fixation disparity" It is considered possible to separate This indicates the possibility that the method of the present invention can use the reaction time as a parameter for visual field region detection.

  Next, a method for calculating the second reference time suitable for each subject from the measured reaction time will be described. The test subject was a healthy adult male (22-24 years old). The central visual field is a red target having a radius of about 2 mm.

  The measurement procedure is as follows. (1) The test subject covers the eye opposite to the test eye (right eye) with the eye patch. (2) The subject sits on a chair wearing the head camera unit of the line-of-sight position detection device at a position of about 700 mm from the display. Then, the head is fixed in a state where the center of the display area is in front of the examination eye. (3) The measurer performs a calibration process to associate the actual line-of-sight position with the line-of-sight position detected by the apparatus. (4) The measurer presents a measurement screen to the subject. (5) The subject gazes at the fixation point presented on the initial screen. If the visual target presented with the fixed viewpoint as the origin can be visually recognized, the line of sight is moved in that direction and position. If you can't see anything, keep an eye on the fixed point. (6) When the line of sight remains for a fixed time with respect to the fixed viewpoint, it is assumed that the subject cannot recognize the target, and the subject is informed by the warning sound that the target is not visible. (7) When the warning sound is heard, the subject moves the line of sight for the target search. (8) After all trials are completed, the measurer closes the measurement screen. Note that the measurement procedures (6) and (7) are procedures when the target is not recognized.

  The target was presented twice at the positions shown in FIG. 9 (positions indicated by reference numerals 1 to 23). In addition, since the position shown by the codes | symbols 12 and 13 uses the right eye as a test | inspection eye, it is assumed that it is a place with the Marriott blind spot which is a human physiological blind spot.

Table 2 shows the average, standard deviation, and 6 × standard deviation (second reference time) of reaction times measured by this experiment for each subject.

  The values shown in Table 2 are reaction time parameters obtained when the target is presented at a position where the target can be reliably recognized by the subject. When the target was presented within the Marriott blind spot, the gaze remained at the fixed point until all the subjects made a warning sound (approximately 3000 msec), so the target was presented within the Marriott blind spot. Reaction time values are excluded from Table 2.

  10 to 11 are histograms of the reaction time of each subject. The bold line shown is the second reference time calculated by Equation 1. As can be seen from the tendency of the histogram, the tendency varies depending on the subject, and it can be seen that there is an optimal second reference time for each subject. Therefore, it is possible to determine whether the visual target is visually recognized using the second reference time for each subject.

  Next, examples of the visual field inspection system according to the present embodiment will be described. The test subject was a healthy adult male (30-60 years old). The visual stimulus is a red visual target having a visual field of about 0.2 deg in the central visual field and a red visual target having a visual field of about 2.9 deg in the peripheral visual field. The target presentation position is in the vicinity of the Vielm region, Marriott blind spot, and nose side stairs (see FIG. 12). The display resolution is 1920 × 1200 [pixel] (6 screen configuration). The luminance is background luminance 510 [asb] and target luminance 153 [asb].

  First, a reaction time measurement test is performed. The reaction time of the subject is measured, and a threshold value (second reference time) of the reaction time is determined based on the measured average value and standard deviation of the reaction time. The number of presentations of the target is 20 times, 10 points in the central visual field and 10 points in the peripheral visual field.

  Next, visual field measurement inspection (global inspection) is performed. Using the reaction time threshold determined by the reaction time measurement test, if the reaction time exceeds the threshold, the visual target of each subject is evaluated by assuming that the presented target is in an area invisible to the subject (abnormal judgment) It was. Assuming that the test is performed on a subject who actually has glaucoma as the target location of the optotype, within the Vielm region (within the dotted line X in FIG. 12) and within the Marriott blind spot (within the dotted line Y in FIG. 12). The target was presented. In the peripheral visual field, the target was presented in the nose side region (inside the dotted line Z in FIG. 12) including the nose side staircase. The number of presentations of the target is 55 times, 23 points × 2 in the central visual field and 9 peripheral visual points.

  Finally, visual field measurement inspection (precision inspection) is performed. The visual target is presented around the presentation target (up / down / left / right 3 deg) for the point that the visual field inspection system is invisible in the visual field measurement inspection (global inspection), and final confirmation is performed.

  The measurement procedure is as follows. (1) The test subject covers the eye opposite to the test eye (right eye) with the eye patch. (2) The subject sits on a chair wearing the head camera unit of the line-of-sight position detection device at a position of about 700 mm from the display. Then, the head is fixed in a state where the center of the display area is in front of the examination eye. (3) The measurer performs a calibration process to associate the actual line-of-sight position with the line-of-sight position detected by the apparatus. (4) The measurer presents a measurement screen to the subject. (5) The subject gazes at the fixation point presented on the initial screen. If the visual target presented with the fixed viewpoint as the origin can be visually recognized, the line of sight is moved in that direction and position. If you can't see anything, keep an eye on the fixed point. (6) When the line of sight remains for a fixed time with respect to the fixed viewpoint, it is assumed that the subject cannot recognize the target, and the subject is informed by the warning sound that the target is not visible. (7) When the warning sound is heard, the subject moves the line of sight for the target search. (8) After all trials are completed, the measurer closes the measurement screen. Note that the measurement procedures (6) and (7) are procedures when the target is not recognized.

Table 3 shows the average value, standard deviation, and threshold value (second reference time) of the reaction times of the subjects A to C and E to J obtained from this test. Table 4 shows the average reaction time of healthy adult males (all in their 20s). The visual fields (test results) of the subjects A to C and E to J evaluated by this test are shown in FIGS.

  From the above test results, the average reaction time of healthy adult males (30 to 60 generations) was 1046.11 msec and the standard deviation was 135.49 msec. The average reaction time of healthy adult males (20's) in Table 4 tends to be slower compared to the average reaction time of 969 msec and standard deviation of 111.12 msec, but the difference is 100 msec. There was no significant difference.

  The first reference time is the previous test result (in healthy adult male college students (22-24 years old)) (see Table 2) and the above test result (in healthy adult males (30-60 years old)) It can be seen from (see Table 3) that it is preferably set to 3 seconds or more, more preferably 4 seconds.

  Regarding the relationship between the age difference and the test result, the line-of-sight data obtained from the test is almost the same in the 20s and 50s, and no specific point is seen in the line-of-sight data of the 50s. Therefore, even if the ages are different, the visual field can be evaluated by the visual field inspection system.

  As for the visual field detection results, the position where the Marriott blind spot is located is defined as “invisible area”, and the other area is defined as “visible area” (see FIG. 12). In the 20s, the visual field inspection system evaluates the subject to be a “visible region” with a probability of 99.4% for the “visible region”, and the probability of 0% for the “invisible region”. It was evaluated as “invisible area” for the subjects. In healthy adult men (30-60s), the visual field inspection system evaluates the “visible region” for the “visible region” with a probability of 98.4% of the visibility rate, and misidentifies the “invisible region”. A probability of 44.4% was evaluated as an “invisible area” for the subjects.

  However, in this examination, the visual field was evaluated by the visual field inspection system with the eyeglasses removed for the subjects whose eyesight was corrected with glasses or the like. In such a case, the subject cannot accurately recognize the center of the fixation point, for example, subject C (see FIG. 14A), F (see FIG. 15A), J (see FIG. 17). As you can see, there is a place where you can see the position of the blind spot of Marriott. In such a case, the visual field inspection system described above is provided with glasses capable of detecting the visual line position of the subject with the visual line position detection device so that the inspection can be performed with the subject's visual acuity corrected. It is preferable to do.

  In addition, as the age increases, the number of people who have eyelid drooping tends to increase, and thus the upper visual field may be narrowed. For example, it is the case of subjects E (see FIG. 14B), G (see FIG. 15B), H (see FIG. 16A), and I (see FIG. 16B). In such a case, it is preferable to raise the eyelid with a tape or the like when performing the visual field inspection system described above.

  Visual field evaluation was also possible for subjects in their 30s to 60s, who are considered to have a difference in reaction time, and thus the visual field inspection system is considered to be effective for a wide age group.

  In this way, when the gaze of the subject gazing at the fixation point moves from the fixation point and reaches the target, the determination unit of the control device determines whether the line of sight is based on the gaze position detection signal input from the gaze position detection device. It is determined that the target has been reached, and the fixation point that has not been watched by the subject is extinguished. At this time, the target that the subject is gazing at becomes a new fixation point. The subject continues to watch the new fixation point until a new target is presented on the presentation device. The control device causes a new target to be examined for a new fixation point to be presented in the display area of the presentation device, and this is repeated until the targets are presented in all visual fields to be examined. Since the fixation point presentation position is not fixed in this way, the subject does not have to return the line of sight to the fixation point again when the line of sight reaches the target from the fixation point, and can objectively inspect the visual field in a short time.

  The time required to move the line of sight from the fixed viewpoint to the target when a general subject visually recognizes the target (for example, 2 seconds in the case of an adult male) is set as the first reference time, If the time is equal to or longer than the first reference time, the determination unit determines that the subject has not recognized the target and treats the visual field corresponding to the presented target as abnormal. Therefore, whether or not the subject can visually recognize the target can be determined based on whether the line of sight moves from the fixed viewpoint to the target within the first reference time. If the subject's line of sight does not reach the target from the fixed viewpoint within the first reference time, the target position control means can move to the inspection of another visual field to be inspected, and the inspection time can be shortened. .

  In addition to the first reference time, the visual field abnormality can also be evaluated by the second reference time. Since the second reference time is calculated from the reaction time when each subject recognizes the target based on the determination result of the determination means, the second reference time is not affected by individual differences in the reaction time for each subject. It's time.

  The subject knows that the visual target has already been presented on the presentation device by notification by the notification means. The target position control means of the control device can cause the subject to search for the target and move the line of sight to the target in order to move to the visual field to be examined next.

  In contrast to the conventional visual field inspection, a precise inspection is performed for each point in the visual field. In the present invention, first, a global inspection is performed to determine whether there is an abnormality in the visual field of the subject. Then, a means for inspecting a place where an abnormality is found to determine the area in more detail is used. In this way, the inspection time can be shortened by using an inspection method that is more time efficient than the conventional visual field inspection method.

  Conventional visual field inspection uses a light target as a target. Regarding the Goldman perimeter, the brightness and size of the target are fixed, moved from the periphery toward the center, the isopter is obtained, and the visual field of the patient is evaluated from the obtained isopter. In order to obtain a correct isopter, the contrast between the screen and the target must always be kept constant. Further, with respect to the Humphrey perimeter, a certain range of luminance values is obtained, the luminance value of each examination point is estimated therefrom, and the state of the patient's visual field is evaluated from the obtained luminance value. When the visual field is evaluated from the luminance, it is necessary to always maintain the contrast between the screen on which the target is projected and the target. From the above, in the conventional visual field inspection, an inspection in a dark room was indispensable as an inspection environment. With respect to this problem, in the present invention, instead of evaluating the visual field from luminance, it is considered to evaluate from the reaction time and movement trajectory of the eye movement representing the target recognition. For this reason, in the present invention, it is not necessary to consider the contrast between the screen and the target, and it is considered that there are few restrictions due to the inspection environment. Then, by using the display of the line-of-sight position detection device and the information processing device as the inspection device, the inspection can be performed without being restricted by the environment as long as the system and the device used for the inspection are available.

  As a method to determine whether or not a target was detected, in visual field inspection using stereotaxic reflection, even if eye movement occurred, the amount of eye movement jumped was small, so that the eye movement could detect the target. It has been difficult to distinguish between eye movements due to stereotaxic reflections that indicate this and accidental eye movements (for example, microscopic eye movements). For this reason, there is a risk that an erroneous result will be output, such as it is judged that an area that should not be seen by the subject is seen, and the test result may be unreliable It is mentioned as a point. With respect to this problem, the present invention focuses on the reaction time of eye movement. If the subject can visually recognize the target, the eye movement is considered to occur in a certain reaction time. If the target cannot be visually recognized, the reaction time of the eye movement is longer than the situation in which the target can be visually recognized. It is thought that the eye movement itself does not occur late. By judging whether the subject is “visible” or “invisible” from the reaction time of eye movement, the problem that is said when using stereotaxic reflection can be solved. In addition, when stereotaxic reflection is used, there is a problem in that stereotaxic reflection is suppressed depending on the number of trials, age, amplitude, etc., and movement itself does not occur. In the present invention, the eyeball intended by the subject is cited. By using motion as a method for determining whether or not a target has been detected, it is not necessary to consider motion suppression due to the effects of the number of trials, age, amplitude, and the like.

  The present invention has a high utility value as a screening device that does not require special equipment such as a dark room in general medical examinations from examinations at medical institutions, and the present invention has a great influence on society through prevention of blindness.

  Note that the visual field inspection system according to the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

  In the visual field inspection system according to the above embodiment, the example in which the presentation device is a liquid crystal display has been described, but the present invention is not limited to this. For example, the presentation device may be a plasma display, or a light source device in which light sources such as LEDs and light bulbs are arranged in a range where a fixation point and a target are presented.

  Although the visual field inspection system according to the above embodiment has been described with reference to an example in which one display is used as a presentation device, the present invention is not limited to this. For example, the presentation device may be a plurality of displays (such as 2 vertical units × 3 horizontal units) or a projector. Since the projector has a low resolution, it is preferable to use a display for the presentation device.

  Although the visual field inspection system according to the above embodiment has been described with the example including the notification unit, it is not limited thereto. When it is determined that the subject cannot recognize the target after the predetermined time has elapsed, the target is extinguished and the fixation point is moved to the position of the line of sight detected by the line-of-sight position detection device. Also good.

  Although the visual field inspection system according to the above embodiment has been described with respect to an example in which inspection is always performed using a point stimulus having a constant luminance, the present invention is not limited to this. It is also possible to perform an inspection by using an optical illusion phenomenon (25 Hz black-and-white inverted flicker stimulation), which has been reported to be able to capture abnormalities of M cells, taking advantage of software, as a visual stimulus.

  Although the visual field inspection system according to the above-described embodiment has been described with the example in which the notification unit 5 issues a warning sound to audibly notify the user, the present invention is not limited thereto. The notifying means may visually notify the user by changing the shape, brightness, coloring, and the like of the target and the fixed viewpoint presented on the presentation device.

  Although the visual field inspection system according to the above embodiment has been described as an example in which it is determined by the reaction time whether or not the subject visually recognizes the target and moves the line of sight, the present invention is not limited thereto. Whether or not the subject visually recognizes the target and moves the line of sight may be determined based on an eye movement trajectory in which the line of sight moves from the fixed viewpoint to the target. More specifically, the determination may be made based on whether or not the shortest distance has passed from the fixed viewpoint to the target, and whether or not the line of sight has reached the target from the fixed viewpoint. The control device can detect such information from the line-of-sight position detection device.

  DESCRIPTION OF SYMBOLS 1 ... Visual field position detection apparatus, 2 ... Presentation apparatus, 21 ... Test | inspection display part, 22 ... Marker, 23 ... Control apparatus for presentation apparatus, 3 ... Control apparatus, 31 ... Control part, 32 ... Display part for result display, 33 ... Input means, 34 ... CPU, 35 ... RAM, 36 ... ROM, 37 ... first determination program (determination means), 37a ... first determination main program, 37b ... storage program (storage means), 37c ... peripheral visual field addition program 38 ... notification program, 39 ... target position control program (target position control means), 40 ... reference time calculation program (reference time calculation means), 41 ... second determination program, 42 ... abnormality determination program, 42a ... abnormality Determination count value totaling program, 42b ... abnormality determination main program, 43 ... determination result display program, 5 ... notification means, a, a0, a1 ... fixed viewpoint, , B0, b1 ... target, A, B ... attention judgment area, t ... motion trajectory, P ... subject

Claims (2)

A visual field position detection device for detecting the visual line position of the subject and outputting the visual line position detection signal;
A presentation device for presenting a fixation point and a visual target separated from the fixation point by a predetermined interval to a subject in a display area;
In a visual field inspection system comprising a control device for controlling the presentation device to present a fixation point and a visual target,
The control device
Determining means for determining whether or not the subject's line of sight has reached the target from a fixed viewpoint within a first reference time set in advance based on the line-of-sight position detection signal received from the line-of-sight position detection device;
When the determination means determines that the subject's line of sight has reached the target from the fixed viewpoint within the first reference time, the subject's line of sight reaches the target from the fixed viewpoint after presenting the target. Storage means for storing the reaction time required for the measurement a plurality of times;
When the determination means determines that the target has been reached, the fixation point presented on the presentation device is extinguished, and the visual target presented on the presentation device is made a new fixation point, and the fixation point is inspected. A target position control means for presenting a new target at an arbitrary position within the display area;
When the number of times of measurement of the reaction time stored in the storage means reaches a predetermined number, the subject's line of sight has reached the target from the fixed viewpoint by performing a predetermined calculation based on the reaction time for the predetermined number of times. And a reference time calculation means for calculating a second reference time for determining whether or not the visual field inspection system.   2. The visual field inspection system according to claim 1, wherein the control device further includes notification means for informing when the visual line of the subject does not reach the target within the first reference time.

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