Abstract: most of the causes of myopia are the long anterior and posterior axis of the eye (called axial myopia), followed by the strong refractive power of the eye (called refractive myopia). Myopia mostly occurs in adolescence, and genetic factors have a certain impact, but its occurrence and development are closely related to insufficient lighting, improper reading posture, long-distance work, etc.
myopia is a symptom that the eye can’t see far things, but can see near things. On the premise of static refraction, distant objects cannot converge in the retina, but form a focus in front of the retina, resulting in visual deformation and blurring of distant objects. Myopia is divided into refraction and axial myopia. Refractive myopia is the most serious. Refractive myopia can reach more than 600 degrees, that is, high myopia.
method / step
myopia refers to a refractive state in which the focus falls in front of the retina after the parallel light passes through the refractive system of the eye without adjustment. Therefore, myopia can not see the distant target. If the target is gradually moved closer to the eye and the light emitted is scattered to a certain extent, the focus will move backward. When the target moves closer to a certain point in front of the eye. The closer this point is to the eye, the deeper the degree of myopia. The causes of
myopia are mostly the long anterior and posterior axis of the eye (called axial myopia), followed by the strong refractive power of the eye (called refractive myopia). Myopia mostly occurs in adolescence, and genetic factors have a certain impact, but its occurrence and development are closely related to insufficient lighting, improper reading posture, long-distance work, etc. Most myopia occurs in adolescents. The degree of myopia deepens year by year in the stage of development and growth, and does not develop or develops slowly after maturity. The degree of myopia rarely exceeds 6D, there is no degenerative change in the fundus, and the vision can be corrected with glasses, which is called simple myopia. Another kind of myopia occurs earlier (between 5 and 10 years old) and progresses rapidly. It continues to develop after the age of 25. The degree of myopia can reach more than 15d. It is often accompanied by fundus changes and vision is not easy to correct. It is called degenerative myopia. In addition, it is customary to call myopia below 3D as mild myopia, those with 3 ~ 6D as moderate myopia, and those with more than 6D as high myopia.
China has become the largest country in the world, but few people take preventive measures, mainly because there is no accurate and portable instrument. In China, 20% of myopia is formed without timely discovery, 60% of myopia is slowly evolved from pseudomyopia to true myopia, and 20% is determined by heredity. Children before the age of 12 will cause pseudomyopia due to improper eye habits. However, pseudomyopia can be prevented from evolving into true myopia through external intervention. Household optometry can be used to restore pseudomyopia and alleviate visual fatigue.