JP2000287927A - Vision function measuring apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vision function measuring method and apparatus which allows objective and reproducible classification into detailed grading for a low vision. SOLUTION: In this measuring apparatus, an examinee wears goggles 140 on his eyes and is let to look at light of red, green, blue or the like inside the goggles separately on the right and on the left. A headphone 150 is used to let the examinee hear a beep sound (click sound) to arouse caution and a push button switch 160 to detect the reaction from he examinee. For example, inside the goggles 140, four LEDs each are mounted in front of right and left eye balls separately to generate colors of red, green, blue and white. The LEDs are controlled by a CPU to emit colors at a determined intensity and at a fixed timing. The headphone 150 and the push button switch 160 are all connected to a CPU substrate 110 and controlled by a microprocessor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to a measurement for performing a grade classification at a low visual acuity and evaluating a visual function.

[0002]

2. Description of the Related Art For example, the disease of retinitis pigmentosa progresses,
If the visual acuity cannot be represented by a number (a visual acuity of 0.1 cannot be read at a distance of 1 m), an index valve (showing the examiner's finger in front of the eye, ), A manual valve (if you do not know the number of fingers, move your hand in front of you and show its movement), a light valve (if you do not know the movement of the hand, put light into the pupil in a dark room, The visual acuity is evaluated in three stages of determining the contrast. However, when trying to treat a patient with such a disease or to evaluate the progress of the disease state in detail, these three steps are too crude and hard to show a change. Stimulating the eye with strong light for the measurement may also damage the photoreceptors.

[0003] There is also a measuring method using an inspection apparatus using stimulating light from a white LED (for example, Kunikata Hoshi, Tsunoda Masahiro, Tamai Shin "Grade classification of extremely low visual acuity and development of measuring equipment therefor"). Journal of the Japanese Ophthalmological Society, Vol. 102, extra edition p. 152 1998). However, in this method, since white light is used, it is not always possible to make a distinction to such an extent that a fine classification can be made so as to clarify the progress of a disease or a therapeutic effect in low vision.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a visual function measuring method and a measuring apparatus capable of finely classifying objectively reproducible, especially in low visual acuity which could not be clearly evaluated in the past. It is to be.

[0005]

In order to achieve the above object, a visual function measuring apparatus according to the present invention comprises a light generating means for individually generating at least red, green and blue light for each of right and left eyes. A light emission control unit that controls the light generation unit to control the light stimulating stage; and a unit that detects whether or not the subject has responded to the light in each of the stimulating stages. And The results obtained by this measurement device are defined by spatial resolution and differ in character from the conventional "sight" which is the ability to discriminate between two points. However, in this measurement, it is possible to objectively reproducible, fine grade classification in low vision that could not be clearly evaluated in the past, and comprehensive visual function evaluation including cone and rod functions is possible It is. Also, even when eyesight is obtained, since red, green and blue color lights are used,
It is possible to independently measure the functions of the cones that produce three types of color vision, that is, the macular function.

In this visual function measuring apparatus, the light generating means may include means for generating white light.
Further, it is desirable that the light emission control means randomly controls the selection of the stimulus stage. The light emission control means controls light intensity and / or light emission time as the stimulation step. It is desirable that the light generating means is constituted by an LED.

[0007] Further, there is provided a means for generating a sound, and the light emission control means performs a control for emitting light after generating a sound, thereby giving a stimulus after alerting the subject's attention. it can. At this time, by performing control that does not generate light after generating sound, data on the reliability of measurement can also be obtained. A visual function measuring method using the above-described measuring device is also the present invention.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention uses at least three primary colors of light, red, green, and blue, and examines a response to a stimulus to each light. The result obtained by this measurement is that, for example, nine levels of stimulus light intensity are set by a combination of stimulus luminance and stimulus time, and are defined by spatial resolution.
It differs in character from the conventional "sight" which is the ability to distinguish between two points. However, this measurement enables comprehensive visual function evaluation including cone and rod functions. Embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an example of the configuration of an embodiment of the measuring apparatus of the present invention, which is configured using a microprocessor. In FIG. 1, a CPU board 110 centering on a microprocessor (CPU) for controlling the present invention and a display board 120 on which a panel for displaying settings and states of the measuring apparatus are mounted in a housing 100 of the measuring apparatus. Is in. The CPU board 110 connects to the printers 130 and 1 for printing out the measurement results.
34 are connected. The power source is a dry cell 1
78 or the AC adapter 170.

In this measuring apparatus, the subject wears goggles 140 on his / her eyes, and shows red, green or blue light from inside the goggles separately from left and right. In addition, headphones 150 for sounding a buzzer sound (click sound) for alerting the subject and a push button switch 160 for detecting a reaction of the subject are also used. In the goggles 140, for example, four LEDs are mounted in front of the left and right eyes, respectively, in order to generate light of each color of red, green, blue, and white. Each of these LEDs emits light with a predetermined intensity and a light emission time under the control of the CPU.
Also, the headphone 150 and the push button switch 160
Are all connected to the CPU board 110 and are controlled by a microprocessor.

In the case of the measuring device of the embodiment, the goggles 14
Each LED in 0 is red (wavelength 644 nm), green (52
5 nm), blue (470 nm), and white light. Further, the light generated from each LED is high (H),
The intensity can be changed in three steps of medium (M) and low (L), but the stimulating light intensity is 0.1, 1, 10 cd / m
² (or 1, 10, 100 cd / m ² ). Also, the light emission time is 0.1, 0.3, 1.0 second,
It can be set to three steps of 0.01, 0.03 seconds, and 0.1 seconds. Note that the stages of the light emission intensity and the light emission time of these lights are not limited to the three stages exemplified in the embodiment. The number of stimulus stages and specific numerical values of those stages can be set in various ways.

A description will be given of how an inspection is performed using such an apparatus. For the subject, focus the attention on the buzzer sound from the headphones 150,
For example, after 0.7 seconds, the LEDs in front of the left or right eye in the goggles are caused to emit light with random intensity and light emission time. When the subject can recognize the light emission, the push button switch 160 is pressed. This reaction is detected by a microprocessor (CPU).

[0013] The state of light emission of the LED is
Since light intensity and light emission time are each in three stages,
There are 9 stages and one color LED is on the left and right, so that 9 × 2 = 18 for each one color LED
There is street light emission. Even if a buzzer sound is added to this LED
There are 20 cases including 10% when no light is emitted. In this way, the case where the LED does not emit light is included.
This is to check the reliability of this measurement. In the measuring device of the embodiment, in the initial setting, the number of light emission stimuli in a series of measurements for each color LED is, for example, 60 times (each L
3 times for each stage of ED), 100 times (5 times), 200
(10 times).

FIG. 2 shows a front panel 20 of the apparatus according to the embodiment.
0 is shown. With this panel 200, it is possible to set the state and operation of the measuring device. When the series of measurements is completed, the printer 130 prints out the series of measurement results. This will be described in detail later.

In the panel 200, when the power switch 210 is turned on, power is supplied to the measuring device from the dry battery 178 or the like, and the power indicator 250 is turned on. When the measuring device can be started, the inspection indicator 260 lights up and goes off during the inspection. When the start switch 220 is pressed after the inspection indicator light 260 is turned on, a series of inspections (for example, 60 light emission stimuli) starts. Note that if the start switch 220 is pressed during the inspection (the inspection lamp is turned off), the inspection can be stopped. The volume switch 230 can switch the volume of the buzzer sound from the headphones 150 in three stages. LE
LED used for inspection using D changeover switch 235
Select A series of tests are performed using the selected LEDs. When inspecting all of the red (R), green (G), blue (B), and white (W) light, it is necessary to sequentially switch and perform a series of inspections four times. Lighting time switch 240
Are the aforementioned light emission times of 0.1, 0.3, and 1.0 seconds (× 1)
Or 0.01, 0.03 seconds, and 0.1 seconds (× 0.1). The buzzer indicator light 270 lights when a buzzer sound is being emitted. The LED stimulus display lamp 280 displays the LED stimulus status to the subject, and lights up while the LED stimulus is being performed. The LED stimulation indicator 280 is connected to the right eye (RIG
HT), corresponding to L (low brightness) 281, M (medium brightness) 2
82, H (high brightness) 283, and left eye (LEFT)
L (low brightness) 285, M (medium brightness) 286, H
(High brightness) 287 are provided for each three.
When the subject responds to the LED lighting by pressing the push button switch 160, the subject response indicator light 290
Lights up. At this time, YES 292 is lit
This is a case in which the subject responds after the LED emits light. L
If there is a response before the ED is turned on or the LED is not turned on, the ERROR 294 is turned on.

The relationship between the buzzer sound from the headphone 150, the lighting of the LED in the goggle 140, and the response of the subject by the push button switch 160 will be described with reference to the time charts of FIGS. The operation timing according to the following time chart is an example, and is not limited to this.

FIG. 3 shows a time chart when the subject does not respond. After the buzzer sounds for 0.3 seconds,
After 0.7 seconds, the LED is, for example, 0.1 seconds (or 0.
(3, 1.0 second). The light emission intensity and light emission time of the LED are randomly determined by the measuring device. Since there is no response from the subject (no pressing of the push button switch), a buzzer sounds again after 2.5 seconds from the LED emission, and the next light emission stimulus is started.

FIG. 4 to FIG. 6 are time charts when the subject responds. FIG. 4A shows a case where the subject responds after the LED stimulation. In FIG. 4A, after the buzzer sound is turned on for 0.3 seconds, L is turned on after 0.7 seconds.
ED is 0.1 seconds (or 0.3, 1.0 seconds)
Lights at a certain intensity. After 0 to 2.5 seconds, the subject responds. Then, 1.0 second after the response, the buzzer sounds again and the next light emission stimulus is started. FIG. 4 (b)
Shows the case where the subject responded during LED stimulation.
In FIG. 4B, the LED is illuminated at a certain intensity, for example, for 0.1 second (or 0.3 or 1.0 second) after 0.7 second from the buzzer sound of 0.3 second. The LED
The response of the subject is detected during the lighting. When there is a response, the LED is turned off and the buzzer sounds again after 1.0 second.
The next luminescence stimulus is started.

FIG. 5 shows a case where, unlike FIG. 4B, the LED is not turned off even if the subject responds during the LED stimulation. In FIG. 5, the LED is illuminated at a certain intensity for, for example, 0.1 second (or 0.3 or 1.0 second) after 0.7 second from the buzzer sound of 0.3 second. That L
The response of the subject is detected during the lighting of the ED. Even if there is a response, the LED is not turned off. After the response, the buzzer sounds again 1.0 seconds later, and the next luminous stimulus is started.

FIG. 6 is different from FIG. 5 in that the time interval of the stimulus changes depending on the response time (ie, when the next stimulus is started after a certain period of the subject's response). This shows a case where the time interval is constant. FIG.
At 0.7 seconds after the buzzer sounds for 0.3 seconds, the LED is set to, for example, 0.1 seconds (or 0.3 or 1.0).
Lights at a certain intensity for a second). The response of the subject is detected while the LED is lit. Even if there is a response, the LED is not turned off. 2.5 seconds after the LED is turned on, the buzzer sounds again, and the next light emission stimulus is started. Thus, measurement can be performed at various timings. This timing can be set arbitrarily.

FIG. 7 shows an example in which the measurement result is printed out by the printer 130 at the time when a series of measurements is completed as described above. In FIG. 7, items to be printed out include a date (DATE) and a name (NAM).
E), display of columns for writing age (AGE), gender (SEX), etc., and measured LED colors (GREEN
Etc.), display of the light emission time switch (T = × 0.1), measurement result of right eye (RIGHT), left eye (LEF)
The measurement result of T), the number of times the subject has responded (ERROR) despite the absence of LED stimulation, and the like are displayed.

The measurement results are shown for the right eye and the left eye separately for each stimulation time and luminance level (L, M, H), where the numerator is the number of responses of the subject and the denominator is the number of stimulations. . In addition, the result as ERROR is obtained when the subject responds before the LED is stimulated, and when the luminance is 0 (LE even when a buzzer sound is heard).
The total number of times of response to the stimulus (when D does not emit light) is used as the numerator, and the denominator indicates the total number of stimuli. The reliability of the measurement data can be evaluated by the number of ERRORs.

FIGS. 8 to 11 show the results of measurements actually performed on subjects having various symptoms using the measuring apparatus of the embodiment. In each figure, (a) is red (re
d) and (b) are green, and (c) is blue (blue)
e) and (d) show the measurement results in a table in which the stimulating light of each color of white (white) is vertically set to the emission time (unit is seconds) and the horizontal is the light intensity (unit is candela / m ² ). Is shown.

FIG. 8 shows the results of five measurements for each color of a 59-year-old female with age-related macular degeneration. The woman's vision is 0.6 on the right and 0.03 on the left. In the measurement of white, no clear decrease in the response to the decrease in the stimulating light is observed, but red (red), green (gre)
en) and a clear decrease in response to a decrease in the stimulation light of each color of blue.

FIG. 9 shows the results of three measurements for each color of a 46-year-old woman whose left eye has age-related macular degeneration. As the visual acuity of this woman, the right is 0.8 and the left is a light valve (discriminating light and dark). From the measurement result, in the left eye, red (re
A clear decrease in response to the decrease in the stimulus light in d) is observed.

FIG. 10 shows the results of five measurements for each color of a 61-year-old woman with retinitis pigmentosa in both eyes. The eyesight of this woman is 0.06 on the right and 0.02 on the left.
It is. From the measurement results, a clear decrease in response to a decrease in red (red) stimulating light is seen. Green (green)
n) and white (white) also show response degradation.

FIG. 11 shows the results of three measurements for each color of a 62-year-old man with binocular retinitis pigmentosa. The visual acuity of this man is an index valve for both eyes (the number of fingers in front of the eyes can be recognized). From the measurement results, a clear decrease in response is seen although the tendency slightly changes with respect to the decrease in the stimulating light of each color.

From the measurement results, it was possible to classify the manual valve and the exponential valve, which were difficult to distinguish by white light stimulation, for example, reflecting the macular cone function. Also 0.01
In some of the patients with the above-mentioned visual acuity, a decrease in the response is observed, and it is possible to determine a decrease in the function of each color (three types of cones). In the comparison of the three colors, the response to the red light stimulus is often low, and a difference depending on the color component is recognized even if the stimulus light has the same luminance.

As described above, the use of this measuring apparatus makes it possible to evaluate the degree of the difference in cases where only the index valve, the manual valve, and the light valve were evaluated by the conventional inspection method. In addition, in the case of a visual acuity of 0.01 or more, a decrease in response is seen in this test, and the degree of the disorder can be evaluated at the level of each of the three types of cones.

For example, various treatments such as irradiation, laser photocoagulation, and pigment epithelium transplantation have been attempted for the increase of age-related macular degeneration accompanying the aging of the population. Judgment of the effect is difficult with conventional inspection methods. This test method can easily evaluate the visual function of patients with low visual acuity, and can examine differences in color components particularly in macular disorders, and can be applied to a wide range of clinical applications. The above-described measurement is particularly effective in the case of focusing on retinitis pigmentosa, diabetic retinopathy, glaucoma, central retinal artery occlusion, age-related macular degeneration, and the like, in which the visual acuity falls below the manual valve. .

[0031]

As described above, the measurement of the present invention
Using each light in the three primary colors, for example, a stimulus light intensity of 9 levels is set by a combination of the stimulus luminance and the stimulus time,
The resulting grade classification is defined by spatial resolution and differs in character from conventional "sight", which is the ability to discriminate between two points. However, this measurement enables comprehensive visual function evaluation including cone and rod functions. For this reason, not only the grade classification in low visual acuity became possible, even when the visual acuity was obtained,
Since red, green, and blue color lights are used, it is possible to independently measure the functions of cones that generate three types of color vision, that is, the macula function.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of a measurement device according to an embodiment.

FIG. 2 is a diagram showing an example of a front panel in the measuring device of the embodiment.

FIG. 3 is a time chart in a case where there is no response from a subject.

FIG. 4 is a time chart when there is a response from a subject;

FIG. 5 is a time chart when there is a response from a subject.

FIG. 6 is a time chart when there is a response from a subject.

FIG. 7 is a diagram illustrating an example of a printout of a measurement result.

FIG. 8 is a diagram showing actual measurement results.

FIG. 9 is a diagram showing actual measurement results.

FIG. 10 is a diagram showing actual measurement results.

FIG. 11 is a diagram showing actual measurement results.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 housing 110 CPU board 114 connector 120 display board 130 printer 140 goggles 150 headphones 160 push button switch 170 AC adapter 178 dry cell 200 front panel 210 power switch 220 start switch 230 volume change switch 240 light emission time switch 250 power indicator 260 Examination indicator 270 Buzzer indicator 280 Stimulation indicator 290 Subject response indicator 350 Changeover switch

Claims (8)

[Claims] 1. A light generating means for individually generating at least red, green and blue light for each of right and left eyes, and a light emission control for controlling the light generating means to control a step of stimulating the light. Means for detecting presence or absence of a response of the subject to light in each of the stimulating stages. 2. The visual function measuring apparatus according to claim 1, wherein said light generating means includes a means for generating white light. 3. The visual function measuring device according to claim 1, wherein the light emission control means randomly controls selection of the stimulus stage. 4. The visual function measuring device according to claim 1, wherein said light emission control means controls light intensity and / or light emission time as said stimulating step. apparatus. 5. The visual function measuring device according to claim 1, wherein said light generating means is constituted by an LED. 6. The visual function measuring device according to claim 1, further comprising: means for generating a sound, wherein said light emission control means controls to emit light after generating a sound. A visual function measuring device characterized by the above-mentioned. 7. The visual function measuring device according to claim 6, wherein the light emission control means performs control not to generate light after generating sound. 8. A subject in each stage of generating at least red, green, and blue light individually for each of the left and right eyes, and changing the intensity and / or emission time of the light. A visual function measurement method comprising: detecting presence / absence of a reaction of the subject; and determining a visual function by using a reaction result of the subject to each stage.