Nearsightedness, also called myopia, is very common today vision defect, namely the violation of refraction. Of myopia is that the light beam is focused either behind the retina or in front of her. As a result, close objects people seen clearly, but distant, blurred.
the Main reason for this is a very strong increase in the eye directly to the anterior-posterior direction. In addition, the irregular curvature of the lens or cornea can also cause blurred vision.
the contemplation of distant objects, and people are sick for myopia can also experience eye strain, headache and other symptoms.
causes of myopia pavlenia
it's Not enough just to know what is myopia. Also you need to know what caused the disease. It is often the main reason is the change in the shape (namely, a lengthening) of the eyeball. In the majority of cases myopia is passed on to children by inheritance from their parents. In addition to its appearance can also contribute to such specific circumstances, such as: cataracts, diabetes or premature labor.
Other causes of myopia can be reading books when she is very close to the eyes, and also long-term work for the PC.
Myopia can suffer both children and adults, at what age the disease will only get worse. There has even been cases of congenital myopia, when she was diagnosed in infancy and she was survived by the maturation of the baby.
On the severity of myopia is divided into 3 degrees:
- high (ranging from 6 diopters and >);
- the average (ranging from 3 up to 6 diopters);
- weak (up to 3 diopters).
during the examination by an ophthalmologist is already possible to observe significant changes of the fundus, which could involve changes in the macula and the appearance of the initial degenerative changes, additionally, the retinal vessels constrict.
the degree of linorulli entails some propagandize. In this case, examinations by an ophthalmologist should take place < 2 times per year.
Translated by "Yandex.Translate": translate.yandex.ru.