Is not myopic before 18 years old already rare? Save the eyes of children

At the end of the long holiday, parents celebrate the return of the beast. The most common greeting is “how much has your child’s degree increased?” < / P > < p > Yes, it is almost standard for senior primary school students to wear glasses, and asking for degrees is as normal as saying “have you eaten?”. During the summer vacation, the reporter learned from Panjiayuan glasses city in Beijing that most children’s myopia has increased by at least 50-100 degrees. < p > < p > on August 27, the Ministry of education survey also showed that the myopia rate of students increased by 11.7% in the past six months compared with the end of 2019. Juvenile myopia prevention and control work is imminent. In fact, the situation last year has been “amazing”. According to a group of data released by the National Health Commission in April 2019, the overall myopia rate of adolescents and children in China is 53.6%. Among them, the myopia rate of junior high school students was 71.6%, and that of senior high school students was 81%. < p > < p > therefore, less than a year later, the number of member units established by nine departments including the Ministry of education has increased to 15. < / P > < p > What are the effects of various factors on vision and how to deal with them? Recently, the reporter interviewed Yang Zhikuan, doctoral supervisor of Aier ophthalmology College of Central South University and deputy head of optometry group of Ophthalmology branch of Chinese Medical Association. According to Yang Zhikuan, the impact on the eyesight of teenagers mainly includes the following aspects: first, continuous near vision work, that is, the use of eyes less than 33 cm and more than 20 minutes. Students usually switch between blackboard and textbook for a 40 minute class in school, which is acceptable in theory, but there is no such switch in the total online class; the second is the effective outdoor activity time, why add “effective”? That is, outdoor illumination should be greater than 700 lux. Outdoor activities at night, the exercise function is still there, but the adjustment of vision is not; the third is the environmental illumination, indoor non reading, also need more than 150 lux to avoid visual fatigue. < p > < p > illuminance is a physical term, which refers to the intensity of light and the amount of illumination on the surface area of an object, referred to as illuminance, in lux. < / P > < p > according to the latest issued by the Ministry of housing and urban rural development in 2018, taking the school as a reference, the illumination requirements for the classroom desktop in the national standard are 300lux and 500lux respectively. This is also the reporter usually reads when the eye is more comfortable illumination range. However, many bookstores and even some libraries visited by journalists often fail to meet this standard. < p > < p > on a cloudy morning, the illumination of the desk close to the window without any obstruction is 700-800lux, and that of the desk 1m away from the window is about 300lux. < / P > < p > many adults don’t tighten the string of ambient illumination and reading illumination. On weekends and holidays, whether in libraries or bookstores with unqualified illumination, the floor and corner beside bookshelves are often filled with readers of all ages. The operators and managers of public reading places are obliged to refer to the national standards and meet the lighting conditions. And we who love reading, especially parents, should understand some “common sense” and resolutely not read and write under unqualified lighting conditions. After all, “digging walls to steal light” and “a bag of fireflies reflect snow” are limited by the times, and inspirational is enough. In addition to looking forward to strengthening the inspection to urge the standardization of illumination in public reading space, the reporter has seen some parents take out rechargeable reading lamps to “fill in the light” for their children in the library with insufficient lighting, which is also an expedient measure. < / P > < p > as for the widely criticized electronic products, what are the main “hazards”? If it can not be completely eliminated in life, how to use it correctly? What’s the difference between close reading and traditional paper books? How much harm does blue light do? Yang Zhikuan also answered these questions one by one. < p > < p > excluding the quality problems of screen reading media, first of all, there are no restrictions on the reading of electronic products. Reading, we need at least one light, but now students, even if the room lights out, lying in the bed can also see the electronic screen, which itself increases the close reading time. For example, it’s not conducive to travel around the subway station and train station when people are waiting for a doctor Pulling out the phone seems to be the best way to kill time. < / P > < p > secondly, the information transmitted by electronic products can be made into animation and video, including interaction, which increases the interest and makes it overtime if you are not careful. In fact, not only students, believe that many adults, even if it is legitimate demand, can not resist the “attraction” of various push, let alone the game that can not come out. < / P > < p > the third is the familiar blue light, which has little to do with myopia, but mainly causes fundus diseases. The display light source of all our electronic products is led. Generally, the light emitted by LED is only “RGB”. Among them, R is red, indicating red; G is green, representing green; and B is blue, representing blue. Among the three color LEDs, the “blue LED” between 400nm and 500nm is the most important and basic. The wavelength is more than 400 nm, which is just focused on the macula, so it is harmful to the fundus. When looking at a mobile phone at night or when the light is poor, the dark pupil environment will be enlarged, and the blue light will enter the fundus without any obstruction. This kind of damage can not be seen in the short term, and it will be endless in the long run. < p > < p > if we say that screen life is unavoidable for all mankind, including teenagers, in addition to the control of distance and time, the more positive way is to increase outdoor activities. < p > < p > on August 29, the “Second National Visual Health Summit Forum” sponsored by people’s network pointed out that the current eye use time of children and adolescents is more than twice the standard, and the effective outdoor exposure time is seriously insufficient. According to the data, from January to July 2020, the distance of all day eye use of adolescents is 32.3 ± 9.4cm, of which 75.3% of them spend more than 2 hours of close eye use every day. < / P > < p > prevention and control of juvenile myopia needs “Photosynthesis”, and outdoor activities are indispensable. The most important means of myopia prevention and control is to receive sunlight, receive stronger illumination, and accept the spectrum and rhythm under the sunshine in outdoor activities. At the forum, Zeng Junwen, chief physician of Zhongshan ophthalmology center of Sun Yat sen University, explained: “why do you always talk about outdoor activities? In fact, outdoor activities are not just about reducing the sight. The role of outdoor activities in receiving light is particularly magical. Many people think that ultraviolet radiation is not good. In fact, some bands of ultraviolet light have a certain positive effect on the development of the eyeball, which has not been studied in depth. My subject is doing the research of red light. Red light was used to treat amblyopia. In fact, after amblyopia treatment, the hardness of children’s eyeballs has also increased, and the eye axis is not very long. ” Liao Wenke, former inspector of the Department of sports, health and arts of the Ministry of education, mentioned that it is an important item to check eyesight in the college entrance examination. Many children who are very gifted in certain aspects can not choose their favorite major due to their eyesight, which seriously affects the cultivation of professional talents in our country. Not only that, “every year after the conscription, the army has to report to us that due to poor eyesight, there are few qualified recruits. The standard of physical examination for conscription has been lowered again and again. According to the original standard, too many qualified recruits can not be found, and it is difficult to complete the recruitment task without lowering the standard.” < / P > < p > the reporter also learned on the forum that after scientific demonstration, one-time exercise for 14 hours on weekends can not play a role in myopia prevention and control. Just like eating meals according to meal, outdoor activities must be spread to at least 2 hours a day. The reality is that, even during the suspension period when the epidemic situation is not too serious, there are few children playing downstairs in primary schools or above. Not to mention the students who are more tight than adults on weekdays. < / P > < p > with glasses, OK glasses, atropine Can these really be mended? For adults who seem to have settled down in dust, can myopia turn a blind eye to the toothache that is not considered a disease many years ago? < / P > < p > it would be too optimistic to think that high myopia is just a little thicker glasses or a narrower major. Once entering the high myopia, the pathological changes are irreversible damage. The risk of cataract, retinal detachment and macular degeneration will increase 5 times, 13 times and 800 times, respectively. The International Association for the prevention of blindness has replaced cataract with high myopia as the leading cause of blindness in the world. The reason that causes high myopia, one is very obvious gene influence. There is also myopia before the age of 12, also known as early onset myopia, this kind of children degree development is very fast, also belongs to the high probability population. Although the third type is found after the age of 12, but with some hidden susceptibility genes, it may also become pathological myopia. Xu Liang, former director of Beijing Tongren ophthalmology Research Institute, stressed that people who were nearsighted before the age of 18 were more likely to have high myopia earlier. Can be “pessimistic” look, 18 years old before myopia is rare. < / P > < p > why is pathological myopia an important cause of blindness, even more “dangerous” than cataract? Because as the degree of myopia becomes higher and higher, the axial length of the eye is also longer and longer. The biological structure of the eyeball has changed. The back of the eye becomes like an olive, and the retina is pulled forward. The retina becomes like a broken cotton wadding, which is fragile. < / P > < p > then how to effectively prevent? It’s not difficult to say that. Our study habits and living habits are an important grasp, such as learning posture, reading distance, reading time, reading intensity and reading lighting, etc. According to Yang Zhikuan, prevention and control of myopia is not only a problem of wearing glasses, but also a problem of losing the ability to work in the future. It’s not just shouting slogans, it can be solved by holding a few meetings. In addition to the warning of “harm”, science popularization is of great importance, especially for parents and school teachers. According to LAN Weizhong, a member of the World Health Organization’s ametropia prevention and control program expert group, in the past few decades, myopia rates around the world have increased to varying degrees. In Asia, especially in East Asia, China, Japan and South Korea ranked first in the global incidence of myopia, reaching 51.6%, followed by the United States and Europe, with the lowest myopia rates in Africa and Oceania Less than 10%.

, an American Journal of Ophthalmology, predicts that the incidence rate of myopia in the world will be as high as 49.5% if there is no effective myopia prevention and control measures. The total population of high myopia is nearly 1 billion. A large number of studies suggest that the main reason for the rapid increase in the prevalence of myopia in the world over the past few decades is that lifestyle changes have taken place. Among the numerous “new” lifestyles, two factors are clearly identified as causing myopia, namely, the increase of learning load and the decrease of outdoor activities. However, the prevalence of myopia in western countries represented by Europe and Australia is still far lower than that in East Asia. From the social level, the evaluation of students in western society, in addition to academic performance, will also consider the comprehensive quality, such as learning ability, specialty, hobbies, development potential, etc., while the traditional culture in East Asia tends to focus on academic studies, especially the “near” learning in the study. Because of the evaluation system