Eye evaluation method and orbicularis oculi muscle strength measurement method

Abstract

To provide a method for evaluating the degree of an eye aging phenomenon.SOLUTION: An eye evaluation method comprising: evaluating a degree of an aging phenomenon of an eye of a subject on the basis of a value indicating a muscle force of an orbicularis oculi muscle of the subject.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for evaluating the degree of aging of the eye, particularly the eye, and a method for measuring the strength of the orbicularis oculi muscle. [Background technology]

[0002] As we age, facial aging phenomena such as wrinkles and sagging skin may occur, which not only cause functional eye problems such as dry eyes and eye strain, but also aesthetic problems such as making the face appear older due to wrinkles and sagging skin. To combat these aging phenomena, various methods have been developed to improve wrinkles and sagging skin. For example, Patent Document 1 describes a light-irradiating cosmetic mask that includes left and right eye electrodes that come into contact with the periphery of the user's eye sockets. Patent Document 2 also describes a beauty method characterized by the following steps: a first step is to attach a face mask consisting of two parts, separated vertically around the mouth and eyes, to the face; and a second step is to press the base end of the muscles running across the face with one hand over the attached face mask while tracing along the direction of the muscles with the other hand in a manner that squeezes out the air, thereby stretching the face mask and skin in the direction of the muscles' running and making them adhere tightly to the skin, thereby promoting the penetration of the active ingredients contained in the face mask into the skin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-027898 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-000341 Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned above, various methods have been developed to combat the aging phenomenon around the eyes from both functional and aesthetic standpoints. However, the conventional techniques do not take into account the degree of aging of the eyes and surrounding areas (whether it is appropriate for the patient's age, more advanced than the patient's age, or less advanced than the patient's age), and it has not been possible to select a method that corresponds to the degree of aging of the patient's eyes. In view of the above circumstances, a first object of the present invention is to provide a method for evaluating the degree of aging phenomena in the eye.

[0005] By the way, there is a muscle around the eye called the orbicularis oculi, which controls the movement of the area around the eye, especially the eyelids. Conventional methods for measuring the strength of the orbicularis oculi muscle are invasive and place a heavy burden on the subject (e.g., STRENGTH OF THE ORBICULARIS OCULI, H. BASIL JACOBS, Brit. J. Ophthal. (1954) 38,560). However, a simple method for measuring the strength of the orbicularis oculi muscle has not been investigated until now. Therefore, a second object of the present invention is to provide a method for measuring the strength of the orbicularis oculi muscle that is non-invasive and reduces the burden on the subject. [Means for solving the problem]

[0006] The present invention, which solves the first problem, is a method for evaluating the eye of a subject, which evaluates the degree of aging in the eye of the subject based on a value indicating the muscle strength of the orbicularis oculi muscle of the subject. According to the present invention, the degree of aging phenomenon in the eye can be evaluated.

[0007] In a preferred embodiment of the present invention, the value indicating the muscle strength of the orbicularis oculi muscle is a surface myoelectric potential measured on the skin at a portion corresponding to the orbicularis oculi muscle when the subject has their eyes closed. According to the present invention, the degree of aging of the eyes of a subject can be easily evaluated.

[0008] In a preferred embodiment of the present invention, the skin corresponding to the orbicularis oculi muscle is the upper eyelid of the subject. According to the present invention, the degree of aging of the eyes of a subject can be evaluated with high accuracy.

[0009] In a preferred embodiment of the present invention, the eye closure time is 1 second or more. In a preferred embodiment of the present invention, the surface myoelectric potential is measured when the subject closes his or her eyes with maximum force. According to the present invention, the degree of aging of the eyes of a subject can be evaluated simply and accurately.

[0010] The present invention, which solves the second problem, is a method for measuring muscle strength of the orbicularis oculi muscle, which includes measuring a surface myoelectric potential at a part of the skin corresponding to the orbicularis oculi muscle while the subject has their eyes closed. According to the present invention, it is possible to measure the muscle strength of the orbicularis oculi muscle of a subject using a non-invasive method that reduces the burden on the subject.

[0011] In a preferred embodiment of the present invention, the skin corresponding to the orbicularis oculi muscle is the upper eyelid of the subject. According to the present invention, it is possible to measure the muscle strength of the orbicularis oculi muscle of a subject using a non-invasive method that reduces the burden on the subject.

[0012] In a preferred embodiment of the present invention, the surface myoelectric potential is measured when the subject is instructed to close his or her eyes with maximum force. In a preferred embodiment of the present invention, the eye closure time is 1 second or more. According to the present invention, the muscle strength of the orbicularis oculi muscle of a subject can be measured with high accuracy.

[0013] In a preferred embodiment of the present invention, the surface myoelectric potential is measured multiple times. According to the present invention, the muscle strength of the orbicularis oculi muscle of a subject can be measured with high accuracy. [Effects of the Invention]

[0014] According to the present invention, the degree of aging phenomenon in the eye can be evaluated. Furthermore, according to the present invention, it is possible to measure the muscle strength of the orbicularis oculi muscle of a subject using a non-invasive method that reduces the burden on the subject. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a plot of the relationship between muscle strength of the orbicularis oculi muscle and age in an example. DETAILED DESCRIPTION OF THE INVENTION

[0016] In the present invention, the term "eye" refers to the eyeball as an organ and the tissues surrounding it. The tissues surrounding the eyeball include the orbicularis oculi muscle and the skin (upper eyelid, lower eyelid, etc.) that corresponds to the orbicularis oculi muscle.

[0017] 1. Eye evaluation method The eye evaluation method of the present invention evaluates the degree of aging in the eyes of a subject based on a value indicating the muscle strength of the orbicularis oculi muscle of the subject. According to the present invention, a novel method for evaluating the degree of aging phenomena in the eye can be provided.

[0018] In the present invention, the term "eye aging phenomenon" refers to an eye phenomenon that occurs with aging, and is, for example, one or more phenomena selected from the group consisting of heavy eyelids, looking sleepy, the onset and / or progression of dry eye, a change in the size of the eye opening (i.e., the eyes becoming smaller), the occurrence of sagging around the eyes, a decrease in firmness around the eyes, and an increase in wrinkles on the forehead. As the orbicularis oculi muscle weakens with age, the area around the eyes becomes saggy and / or loses firmness. In addition, due to weakening of the orbicularis oculi muscle, the upper eyelids appear to droop, which makes the eyelids feel heavy subjectively and makes the person appear sleepy to others. Furthermore, when the orbicularis oculi muscle weakens, the eyelids feel subjectively heavy, and people develop the habit of using the forehead muscles to open their eyes, which increases forehead wrinkles. Furthermore, weakening of the orbicularis oculi muscle leads to incomplete blinking, which can cause or progress dry eye. In the present invention, the aging phenomenon of the eyes may also include the apparent age of the subject's eyes based on a value indicating the muscle strength of the orbicularis oculi muscle of the subject.

[0019] In the present invention, the method for measuring the strength of the orbicularis oculi muscle is not particularly limited, but preferably includes measuring the surface myoelectric potential of the skin in the area corresponding to the orbicularis oculi muscle when the subject has their eyes closed. By measuring the surface myoelectric potential at the skin in the area corresponding to the orbicularis oculi muscle, the myoelectric potential of the orbicularis oculi muscle can be measured in a non-invasive, simple manner that reduces the burden on the subject. In the present invention, "closing the eyes" refers to the subject intentionally closing his or her eyes, and is distinguished from unconscious blinking. The surface myoelectric potential can be measured by appropriately selecting known electrodes and myoelectric sensors, and the measurement method can be determined in accordance with the manual for the device used for measurement.

[0020] The skin in the area corresponding to the orbicularis oculi muscle is not particularly limited as long as it can be the upper eyelid, lower eyelid, outer or inner corner of the eye, etc., as long as the myoelectric potential of the orbicularis oculi muscle can be measured, but it is preferable to measure it on the upper eyelid. By measuring the surface myoelectric potential at the upper eyelid, the surface myoelectric potential of the orbicularis oculi muscle can be measured more accurately.

[0021] The eye closure time is 1 second or more, preferably 1.5 seconds or more, and more preferably 2 seconds or more. There is no particular upper limit to the eye-closing time, but it can be set to, for example, 5 seconds or less.

[0022] Although it is possible to measure the strength of the orbicularis oculi muscle by closing the eyes only once, it is preferable to have the subject close their eyes multiple times. When the subject is asked to close their eyes multiple times, the number of times they close their eyes can be, for example, 3 or more, preferably 5 or more, and more preferably 10 or more. The interval between closing their eyes can be 1 to 1.5 seconds. When the subject's eyes are closed multiple times, the surface myoelectric potential of the orbicularis oculi muscle of the subject is calculated as the arithmetic mean of the measured values. The arithmetic mean may be calculated using the data measured while the subject's eyes are closed, but it is preferable to perform necessary noise removal. It should be noted that noise removal can be achieved by known noise removal processing such as processing using a low-pass filter. The method of analysis when the subject is asked to close their eyes multiple times will be described in detail in the Examples. According to the present invention, the strength of the orbicularis oculi muscle of a subject can be measured more accurately, and therefore the eyes of the subject can be evaluated more accurately.

[0023] Furthermore, the surface myoelectric potential is preferably a measurement value when the subject closes his / her eyes with maximum force. This configuration allows for more appropriate eye evaluation.

[0024] Furthermore, the measurement method described above makes it possible to measure the strength of the orbicularis oculi muscle of a subject non-invasively and with reduced burden on the subject.

[0025] The degree of aging in the eyes of a subject can be evaluated, for example, by the following method. That is, in one embodiment, the relationship between the strength of the orbicularis oculi muscle and actual age is defined in advance, and the measured value of the strength of the subject's orbicularis oculi muscle is compared with the relationship between the strength of the orbicularis oculi muscle and actual age, thereby making it possible to calculate the estimated age of the subject's eyes. In another embodiment, the relationship between the strength of the orbicularis oculi muscle and the evaluation value of the degree of eye aging can be defined in advance, and the degree of eye aging in the subject can be estimated by comparing the measured value of the subject's orbicularis oculi muscle strength with the relationship between the strength of the orbicularis oculi muscle and the evaluation value of the eye aging.

[0026] The eye evaluation method of the present invention may also include other steps. Furthermore, the eye evaluation method of the present invention may be combined with evaluations obtained by other known methods to perform a multifaceted evaluation of the subject's eyes. [Example]

[0027] The present invention will be described in more detail below with reference to examples, but the technical scope of the present invention is not limited to the following examples.

[0028] Example 1: Verification of the correlation between orbicularis oculi muscle strength and chronological age In this example, the correlation between measured values ​​of muscle strength of the orbicularis oculi muscle and actual age was examined.

[0029] The subjects were 60 healthy women in their 20s to 60s (10 from each age group, 20 in their 30s only), and the strength of the orbicularis oculi muscle was measured for each subject using the following measuring equipment and method. <Measuring equipment> Skin pretreatment agent Skin Pure YZ-0019 (Nihon Kohden), DSP Wireless EMG Sensor (Wet) SS-EMGW-HM (Sports Sensing) Electrode: Small disposable electrode BlueSensor N SS-SUN00S (Ambu) <Measurement method> (1) The tester applied a small amount of the skin pretreatment agent to a cotton pad and gently wiped the upper eyelid of the test subject who had washed his face. (2) A disposable electrode was attached to the upper eyelid, and an electromyography sensor was attached to it. The subject was then asked to close their eyes firmly, and the strength of the orbicularis oculi muscle was measured during the forceful closing of their eyes. Each closing was for 1.5 seconds, and the subject was asked to close their eyes a total of 20 times at 1.5-second intervals. <Analysis method> First, noise was removed from the data obtained by the above measurement method using the moving average method (average value was obtained from data for several seconds from any point in time). Next, the amount of change in the signal value of the surface myoelectric potential obtained when the subject closed their eyes was calculated, and the signal value at the point where the condition of less than 1 / 8 of the amount of change and more than 1 / 2 of the maximum signal value was obtained. Note that in this test example, the above signal value was obtained by computer calculation, but for this processing, it is sufficient to obtain the signal value for a 1.5-second interval when the eyes were strongly closed, and it is also possible to use manual interval extraction, for example. Finally, the signal values ​​obtained when the same subject closed their eyes strongly were arithmetically averaged, and this was used as the muscle strength data for that subject. A regression line was created from the plot of the orbicularis oculi muscle strength obtained from the measurements and age, and the correlation coefficient was calculated.

[0030] Figure 1 shows a plot of the relationship between measured orbicularis oculi muscle strength and age. The equation for the approximate line shown in Figure 1 is y = -0.0438x + 6.7378, where y is the strength of the orbicularis oculi muscle (mV) and x is age (years). The Pearson product-moment correlation coefficient r was -0.299, indicating a weak negative correlation, and the p-value of the Pearson product-moment correlation analysis was significant at 0.020.

[0031] As shown in Figure 1, it became clear that the measured strength of the orbicularis oculi muscle tends to decrease with age.

[0032] This test example also suggested that by obtaining the relationship between the measured values ​​of the orbicularis oculi muscle strength and age in advance and then applying the measured values ​​of the subject's orbicularis oculi muscle strength to this, it is possible to evaluate the degree of aging of the subject's eyes (in particular, the apparent age of the subject's eyes). For example, when the measured muscle strength of a subject's orbicularis oculi muscle indicates a certain value, by substituting that value into the approximate straight line obtained in advance as described above, it is possible to evaluate the degree of aging of the subject's eyes in relation to their age.

[0033] It was also suggested that the results of the evaluation of the degree of aging of the subject's eyes obtained as described above can be used to suggest cosmetics and beauty methods suitable for the subject. For example, if the degree of eye aging of the subject obtained as described above corresponds to an age older than the subject's actual age, cosmetics and beauty treatments for older people can be suggested to the subject, and if the degree of eye aging corresponds to the subject's actual age, cosmetics and beauty treatments appropriate for the subject's age can be suggested to the subject. In other words, cosmetics and beauty treatments suitable for each individual subject can be suggested based on the degree of eye aging of the subject.

[0034] Furthermore, the above method is a simpler, non-invasive method for measuring the strength of the orbicularis oculi muscle, and reduces the burden on the subject, compared to conventional methods for measuring the strength of the orbicularis oculi muscle.

[0035] <Test Example 2> Verification of the relationship between measured values ​​of orbicularis oculi muscle strength and aging phenomena In this test example, the relationship between the measured muscle strength of the orbicularis oculi muscle and the aging phenomenon was examined.

[0036] A questionnaire about the aging phenomenon of the eyes was administered to the same subjects whose orbicularis oculi muscle strength was measured in the above-mentioned Test Example 1. The questions about the aging phenomenon and the options to choose from are shown below. <Question items> Q1. Sometimes my eyelids feel heavy. Q2. Sometimes my eyes look sleepy even though I'm not, or people tell me I look sleepy. Q3. I suffer from dry eyes. Q4. I feel like my eyes are smaller than before. Q5. I'm concerned about the sagging and lack of firmness around my eyes. Q6. When I try to open my eyes wide, wrinkles appear on my forehead. <Choices> (1) Always / Very applicable (2) Often / Somewhat (3) Sometimes / Not very applicable (4) Not at all / Not at all applicable

[0037] Option (1) was assigned 1 point, option (2) 2 points, option (3) 3 points, and option (4) 4 points. The average scores of the answers to each of the above questions for the top 7 people with the highest orbicularis oculi muscle strength values ​​in Test Example 1, and the average scores of the answers to each of the above questions for the bottom 7 people with the lowest orbicularis oculi muscle strength values ​​in Test Example 1 were calculated. The calculation results are shown in Table 1.

[0038] [Table 1]

[0039] As shown in Table 1, the average scores of the answers to the above questions of the bottom seven people with the lowest measured orbicularis oculi muscle strength were higher than the average scores of the answers to the above questions of the top seven people with the highest measured orbicularis oculi muscle strength. In other words, it became clear that the phenomena mentioned in the above questions were caused in part by a weakening of the orbicularis oculi muscle, as described in the "Interpretation" column of Table 1.

[0040] Furthermore, the results of Test Examples 1 and 2 revealed that by measuring the strength of the subjects' orbicularis oculi muscles, it is possible to evaluate the severity of one or more of the following eye aging phenomena: heavy eyelids, looking sleepy even when not sleepy, dry eyes, eyes that appear small, sagging or loss of firmness around the eyes, and wrinkles on the forehead when the eyes are opened. Specifically, it was revealed that by defining a relationship between the measured value of the orbicularis oculi muscle strength and a score indicating the degree of eye aging in advance and comparing the measured value of the orbicularis oculi muscle strength of a subject with this relationship, it is possible to estimate the degree of eye aging in the subject. Furthermore, it is possible to suggest cosmetics and beauty methods that are suited to the subject individually based on the degree of eye aging obtained in this way. [Industrial Applicability]

[0041] According to the present invention, the degree of aging phenomenon in the eye can be evaluated. Furthermore, according to the present invention, it is possible to measure the muscle strength of the orbicularis oculi muscle of a subject using a non-invasive method that reduces the burden on the subject.

Claims

1. A method for measuring muscle strength of the orbicularis oculi muscle, comprising measuring a surface myoelectric potential at a portion of the skin corresponding to the orbicularis oculi muscle when the subject has their eyes closed.

2. The method for measuring the strength of the orbicularis oculi muscle according to claim 1 , wherein the skin in the area corresponding to the orbicularis oculi muscle is the upper eyelid of the subject.

3. 3. The method for measuring muscle strength of the orbicularis oculi muscle according to claim 1, wherein the surface myoelectric potential is a value measured when the subject is made to close his / her eyes with maximum force.

4. The method for measuring muscle strength of the orbicularis oculi muscle according to claim 3, wherein the eye closure time is 1 second or more.

5. The method for measuring muscle strength of the orbicularis oculi muscle according to claim 2 , wherein the measurement of the surface myoelectric potential is performed multiple times.

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