In recent years, the prevalence of myopia among adolescents in China has jumped from the fourth place to the second place in the world. According to the statistics of the latest sample survey conducted by the relevant national departments: 28% of primary school students, 58% of secondary school students on average, and 80% of university students, the prevalence of myopia among urban students is higher than that in rural areas, and the prevalence of myopia among females is higher than that among males. This urban-rural and gender difference may be related to the fact that urban students have a heavier burden of schoolwork and study pressure than rural students, and that female students study harder and use their eyes more, with fewer extracurricular activities and physical exercise. How is myopia formed? At present, most scholars believe that prolonged close-distance eye use, such as watching TV, playing games, reading and writing for too long, leading to over-adjustment or adjusting spasm has a close relationship with the development of myopia in adolescents, followed by the high incidence of myopia in preterm infants and low-birthweight infants, and the incidence of high myopia reported in foreign studies is up to 24%. The incidence of high myopia was reported to be as high as 24% in foreign studies. It is thought that it may be related to retinopathy of prematurity. It is also believed that the extra-uterine environment affects the metabolism of the eye and the development of the eye structure in preterm infants, hindering the process of orthokeratology, and therefore, eugenics is advocated. Is myopia genetically related? In recent years, most people believe that both genetic and environmental factors play a role in the development of myopia. Myopia can be inherited in various ways, including autosomal dominant, autosomal recessive, and sex-linked. Some studies have shown that when both parents are highly myopic, their offspring are highly myopic; when one parent is highly myopic and the other is orthoptic, 57.5% of the offspring suffer from high myopia; when neither parent is highly myopic, 22.2% of the offspring suffer from high myopia. Another study shows that the occurrence of simple myopia is influenced by about 60% of genetic factors and 40% by environmental or acquired factors. What is pseudomyopia? As a result of long-term overlooking at the near and thus causing ciliary muscle spasm, there is still part of the adjustment fails to relax when switching to looking at the distance, so that the orthopic eye or mildly farsighted eye manifests the phenomenon of myopia, which is medically called “pseudomyopia”. Characteristics of pseudomyopia: It is not myopia in nature, but a state of regulation spasm of the ciliary muscle, but it can be a stage in the development of myopia. It can also be a state of accommodation spasm that is not myopia due to overuse of accommodation in the hyperopic eye. It can occur in orthokeratology. In hyperopic or even myopic eyes, myopia is reduced or eliminated with rest or the use of ciliary muscle paralyzing agents. The naked eye visual acuity is not too low (usually greater than 0.5), but the visual acuity fluctuates significantly and is affected by environmental factors, accompanied by fatigue symptoms, such as eye soreness. Headache, etc., and is more common in farsighted eyes. It occurs mostly in adolescents. If children and adolescents are not actively prevented and treated, myopia may develop into true myopia. How to recognize true myopia? Methods: ciliary muscle paralyzing agent dilated pupil optometry: 1% atropine eye drops or eye ointment. Classification criteria of true myopia and pseudomyopia: Pseudomyopia: myopia disappears after medication, presenting as orthopia or mild hyperopia. True myopia: myopia not reduced or reduced <0.5 D after medication. Mixed myopia: refractive error significantly reduced (≥0.5 D ) after medication, but still did not restore orthopia. The key to preventing pseudomyopia is to do the "Three Ones" plus the "Six Noes": the "Three Ones" are the eyes one foot away from the book, the hand one inch away from the pen tip, and the chest one fist away from the table; Six "no's": 1, do not lie in bed to read; 2, do not tilt your head or lean over the table to read; 3, do not walk or ride in the car to read; 4, do not read in too weak or too strong light; 5, do not read continuously for a long time; 6, do not read the font is too small, the handwriting is not clear books. Do eye exercises; eat more vitamin A-rich foods such as vegetables such as carrots and animal liver, egg yolks and so on. Watching TV should pay attention to the following matters: 1, the height of the TV set should be level with the line of sight 2, the distance between the eye and the fluorescent screen should not be less than 5 times the diagonal length of the fluorescent screen 3, watch TV indoor open a small light lamp 4, watch TV for 1 hour to take a short break or look into the distance 5, to choose a higher definition of the TV, the screen flickers on the eyesight is harmful. How to treat pseudomyopia? 1, reduce the visual burden, change the bad study habits, study for about 1 hour to rest the eyes for 10 minutes, strengthen the outdoor sports, enhance physical fitness. 2, dilate the pupil antispasmodic medication: 1% atropine or postmatropium eye drops, once a day for three consecutive days. Compound tropicamide eye drops, once a day. 3, fog vision therapy: convex lens to relax the eye regulation 4, other therapies: physical therapy. Acupuncture. Chinese medicine, etc. What should I do if I have myopia? Teenagers under 15 years of age should go to the hospital for dilated optometry in time. Only those who are over 18 years old and have stable myopia for more than 2 years can consider laser treatment.