What causes blindness? Detailed answer

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What causes blindness? Detailed answer

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What causes blindness?

Do you know that there are at least fourteen million blind people in the world? There are many degrees of blindness and therefore it is difficult to define it. Some people don't even see the light. Others can distinguish light from darkness, and nothing more. And still others have some percentage of vision. Of all the blind people on earth, only a small proportion are blind from birth.

Blindness from birth is called congenital. Its causes have not yet been fully elucidated. Blindness after birth is mainly the result of eye disease. General diseases of the body, such as diabetes or meningitis, can also cause blindness, and even more often than purely eye diseases. Accidents and explosions are two other causes of blindness.

In countries where life expectancy is higher due to good health care and a high standard of living, some visual changes often occur in older people. Cataracts and glaucoma may develop. Cataract is one of the most common causes of blindness. A cataract is a clouding of the lens of the eye. The lens, the transparent part of the eye through which light rays pass, becomes cloudy, and only very strong and bright rays of light can pass through it. The result is a significant loss of vision. Cataracts can only be removed by surgery.

In glaucoma, hardening of the eyeball occurs, accompanied by an increase in pressure inside the eye. Today, there are drugs that can treat glaucoma if it is detected in time. One of the main causes of vision loss is trachoma. This is an infectious disease caused by a virus that infects the inside of the eyelids, as well as the blood vessels on the cornea. As a result, the person may become blind. Now treated with antibiotics, trachoma remains common in parts of Europe, Africa and Asia.

Author: Likum A.

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