According to a joint survey by the Ministry of Health and the Ministry of Education, the prevalence of myopia among students in China is close to 60%, ranking second in the world and topping the world in terms of number of people. The myopia rate among elementary school students has reached 34.5%, and myopia among secondary school students has reached more than 70%, with more than 60 million patients. The number of people blinded by myopia reaches 300,000. The danger of myopia can no longer be ignored, and we should have a deeper understanding of the harm myopia brings to young people.
I. Causes of myopia
(1) Congenital factors.
a. Heredity: A father or mother with a high degree of myopia is very likely to pass it on to a child.
b. Variation: The child has myopia even though the parents are not severely nearsighted.
(2) Looking close.
Such as reading books, homework, watching computers, television, etc., the human eye will become more convex when looking at the lens, the eye within the transformation of long, can cause, aggravate myopia.
(3) Astigmatism.
Astigmatism is always clear in one direction and hazy in the other when looking at objects, and always requires partial adjustment, or squinting or head-shifting to make it slightly clearer, which can cause and aggravate myopia.
(4) Amblyopia caused by.
Amblyopic eyes are often accompanied by astigmatism, coupled with their low vision, and often walk very close when watching TV or looking at things that cause and aggravate myopia.
Two, myopia harm
The first point, easy to cause malnutrition, myopia patients with long-term eye fatigue, resulting in insufficient supply of blood oxygen consumption, the nutrients needed to meet the eye in time to consume nutrients, causing malnutrition. This is why many myopic patients have the title of “wire rod” or “small bean sprout”.
The second point, thinking is restricted, scientists have done experiments, found that the human mind only in the unrestrained state to play a normal level, and when the children suffering from myopia frame a pair of glasses, with the world has a layer of lenses that isolate, thinking will be restricted, the direct expression is dull reaction, learning efficiency under. Blindness has exceeded 300,000.
The third point, not confident, poor ability to adapt to the environment, not confident, lack of initiative, poor self-care, excessive myopia dependence on parents, lack of independence, but also prone to anxiety, psychological subhealth state.
The fourth point is that the students are restricted from going on to higher education. They have been studying hard for more than ten years, holding high scores, but they cannot go to the ideal university. Myopic patients are restricted to apply for about 48 majors, vision below 1.5 can not apply for flight technology, navigation technology, fire technology engineering, criminal science and technology, investigation and other majors; myopia greater than 400 degrees can not be admitted to marine technology, marine science, measurement and control technology and instrumentation and other majors; myopia greater than 800 degrees, can not be admitted to geology and minerals, water resources, civil engineering, animal production class, agricultural engineering and other subject classes.
In medical science, myopia of 600 degrees or more is called high myopia. Most high myopia occurs in elementary school, and after maturity, the number of degrees of myopia basically does not increase, this type of high myopia usually rarely exceeds 1000 degrees, with appropriate glasses, vision can generally be corrected more satisfactory. There are a few other high myopia occurs earlier, myopia will continue to deepen with age, and even up to 2000 degrees or more, the fundus often occur a variety of pathological changes, the patient is extremely dangerous.
High myopia can cause a number of intraocular effects, the more common myopia complications are three.
1, flying mosquitoes.
People with this disease, with the rotation of the eye, often in front of the eyes appear black shadow fluttering, like flies in the fly, which is due to the normal colloid-like structure of the vitreous body liquefaction occurred.
2. Macular hemorrhage.
For people with high myopia, the constant pulling on the wall of the eye caused by the enlargement of the eye will cause metabolic disorders in the normal relationship between the retina and the choroidal tissues in the fundus, especially when the small blood vessels in the macula rupture due to pulling and other factors, it will cause macular hemorrhage and cause great damage to the central vision. At this time, the patient feels that there is a fixed black shadow blocking the vision in front of his eyes. Although the hemorrhage can be absorbed by treatment, it will always leave more or less blood marks and affect the vision.
3. Retinal detachment.
This is a more serious complication, and the cause of its onset is more complex. In terms of internal causes, the retinal tissues of highly myopic patients become fragile due to degeneration and atrophy, which makes it easy for the retina to detach and cause blindness. The main external cause is the sudden impact of external force, through the transmission of vitreous, prompting the retina to rupture, resulting in retinal detachment and blindness.
In addition, high myopia patients should be reminded that when you experience vision loss, black shadows floating in front of your eyes, especially lightning-like flashes, or when you feel a fixed black shadow in front of your eyes, you should go to the hospital as soon as possible to see a specialist ophthalmologist for examination, which may be a precursor symptom of retinal detachment or macular hemorrhage and other lesions.
Myopia treatment
(a) Early use of farsightedness lenses (i.e. myopic defocusing lenses)
1. Use defocusing or defocusing telephoto lenses to offset the main cause of myopia, which is “looking close”.
The defocusing distalizer is a second-generation static distalizer, which can be preferred as a basic distalizer.
Automatic (shift-focus) telephoto lenses are the fourth generation, dynamically enhanced telephoto lenses. If you can insist on wearing it every day to watch TV, computer or small picture books for more than 15-30 minutes, you can provide enough hyperopia effect to counteract the occurrence and development of myopia.
2.Use the eye sensitivity (focusing) telephoto lenses (which can improve the eye focusing sensitivity and expand the field of vision) to block the first key link of myopia, namely, the reduction of the pooled field of vision and the second key link, namely, the reduction of focusing sensitivity.
(2) Early treatment of amblyopia
This is because amblyopia can cause form deprivation myopia, which can aggravate myopia.
(3) Astigmatism should be corrected to the full extent
If the astigmatism is more than 400 degrees, reduce 25~50 degrees after correction. Because astigmatism undercorrection and miscorrection, can increase the eye focusing burden. And cause, aggravate myopia.
(d) Avoid strenuous exercise for high myopia.