How does adolescent myopia form?

Abstract: teenagers have strong eye regulation. They can still see objects when the distance between books and eyes is up to 7-10CM. However, if they often read at this distance, writing will make eye regulation extremely nervous, This can lead to refractive (accommodative) myopia, the so-called pseudomyopia.

at present, the problem of ametropia among Chinese teenagers is becoming increasingly prominent, and the rate of poor vision remains high, which has seriously affected the healthy development of Chinese teenagers.

the near vision situation in China is worrying, especially among teenagers,

According to the results of the national survey on students’ physical health, the poor visual acuity rates of primary school students aged 7 to 12, junior middle school students aged 13 to 15, senior high school students aged 16 to 18 and college students aged 19 to 22 are 45.71%, 74.36%, 83.28% and 86.36% respectively, and gradually develop to a younger age.

and

popularize scientific eye knowledge, prevent ametropia and improve eye health awareness have once again become a major focus of health education in China. According to statistics, there are two major factors causing juvenile myopia, the internal cause is affected by genetic factors, and the external cause is the change of eye habits.

external factors of juvenile myopia

1. Too close eye distance. Juvenile myopia is mostly caused by long-term use of eyes too close. Teenagers have a strong ability to adjust their eyes. They can still see objects when the distance between books and eyes is up to 7-10CM. However, if they often read at this distance, writing will make eye adjustment extremely nervous, Thus, flexion can be formed (accommodative) myopia, the so-called pseudomyopia. If the long-term adjustment is excessive, the ciliary muscle cannot stretch flexibly. Due to the excessive adjustment, the convergence effect is strengthened, so that the extraocular muscles exert pressure on the eyeball, the intraocular pressure increases, and the intraocular tissue is congested. In addition, the juvenile eyeball tissue is delicate, the eyeball wall is compressed and gradually extended, and the anterior and posterior axis of the eyeball becomes longer than the normal value Axial myopia, the so-called true myopia. The normal reading distance should be 30-35 cm.

2. Use eyes for too long. Some teenagers don’t rest for 3-4 hours, such as reading, writing, homework and watching TV, and even go to bed late at night. This not only affects their health, but also overburdens their eyes. Their inner and outer muscles are tense for a long time and can’t rest. Over time, when they look far away, their eye muscles can’t relax and become spasmodic, In this way, you will feel blurred in the distance and form myopia. This is why some students’ eyesight drops significantly after a summer vacation. It is generally advocated that you should take a break or look into the distance for 40-50 minutes of continuous reading, writing or watching TV.

3. The lighting light is too strong or too weak. If the light is too strong, such as sunlight, it will cause strong reflection, stimulate the eyes, make the eyes uncomfortable, and it is difficult to see the font. On the contrary, if the light is too weak, the written lighting is insufficient, and the eyes can’t clearly see the font, the head will move forward and get close to the book. Both of the above conditions can lead to eye fatigue, excessive adjustment or spasm of the eyes and form myopia.

4. Read while in the car or walking. Some teenagers make full use of their time, reading while walking or reading in a walking car, which is very bad for their eyes. Because the carriage is shaking and the body is shaking, the distance between eyes and books cannot be fixed, and the poor lighting conditions aggravate the burden on eyes. Often this may cause myopia.