Eye diseases. Myopia (most important)

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Eye diseases. Myopia (most important)

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41. Myopia

Myopia (myopia) is one of the variants of the refractive power (clinical refraction) of the eye, which is formed simultaneously with a decrease in distance vision due to a mismatch in the position of the back main focus in relation to the central zone of the retina.

Myopia is congenital (hereditary, intrauterine origin), with age it progresses and can be malignant. Acquired myopia is a type of clinical refraction. Often, with age, it increases slightly and is not accompanied by noticeable morphological changes in the eyes. This process of refractogenesis is considered as a biological option. But under certain conditions, the frequency of both congenital and acquired myopic refraction is pathological: the so-called progressive myopia is developing. Such myopia progresses in most children in the early school years, so it is often called "school", although this is not entirely correct, since myopia can progress at a more mature age.

Myopia usually appears in childhood, progressing with age. The following factors are of great importance in the development of myopia:

1) genetic, in which myopic parents often have myopic children. Factors such as weakness of the accommodative muscle, weakness of the connective tissue (the sclera becomes extensible, resulting in an increase in the length of the eyeball) can be inherited;

2) adverse environmental conditions, especially during prolonged work at a close distance from the eye. This is a professional, school myopia, easily developing with an incomplete development of the organism;

3) weakness of accommodation, leading to an increase in the length of the eyeball, or, on the contrary, tension of accommodation (inability of the lens to relax), which leads to spasm of accommodation. In contrast to true myopia, with false myopia, vision is restored to normal with drug treatment (i.e., seven-day instillation of a 1% atropine solution). This requires careful observation and skiascopy with the participation of an ophthalmologist. Spasm of accommodation can be eliminated with the help of special therapeutic exercises for the eyes.

The initial signs of false myopia, or spasm of accommodation, a person may suspect in himself:

1) during visual work at close range, rapid eye fatigue, pain in the eyes, in the forehead, in the temples may occur;

2) near visual work can often be facilitated by using weak plus lenses (in this case, this does not mean that a person has farsightedness);

3) it may be difficult or slow to "set" the eyes to different distances, especially when looking from a close object to a distant one;

4) distance vision deteriorates.

Spasm of accommodation, if left untreated, becomes persistent over time, difficult to treat and can lead to true myopia.

Author: Shilnikov L.V.

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