1. Generally, myopia within 300 degrees is called mild myopia, moderate myopia between 300 and 600 degrees, and high myopia above 600 degrees.
2. General 1.0 or 5.0 vision is regarded as normal vision. Those above these two standards are good eyesight, and those below 4.8 are myopia.
The main causes and pathogenesis of myopia;
(1) About 85% of myopia is related to myopia (such as reading books, watching TV and watching computers, that is, myopia can be prevented;
(2) About 1.5% myopia is related to the increase of axial length, which is controlled by congenital variation or heredity, and the treatment effect is poor. It can be seen that juvenile myopia is a preventable and incurable eye disease.
Extended data:
Several habits that damage the health of eyes
Wear goggles when swimming. If you don't wear goggles when swimming or open your eyes underwater, the water in the swimming pool may infect your eyes with bacteria. Wearing contact lenses is more dangerous. Bacteria attached to the lens will cause redness and swelling of the eyes and eventually infect the eyes.
2. Don't use expired eye cosmetics. Mascara usually condenses into lumps after three or four months, and contains bacteria, which may lead to red eye, infection, photosensitivity and even blindness.
Don't forget to have an eye examination once a year. Ophthalmic examination can find problems such as cataract and glaucoma, and can also find the effects of chronic diseases such as diabetes and hypertension on the eyes. Ordinary people should have their eyes examined at least once every two years. If the eye itself has a disease or is over 70 years old, check it once a year and check the eye problem as soon as possible.
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