Myopia is a kind of visual function impairment, in which the eye clearly sees objects at close range, and objects located far away have a blurred outline for it. The second name for this phenomenon is myopia. Such a visual impairment is very common. According to statistics, it is observed for every third inhabitant of the Earth. What is the cause of myopia? What is the mechanism of its occurrence? The causes of short-sightedness lie in the wrong refraction of the organs of vision. The image with such a deviation is formed not in the retina of the eye, but in front of it. Therefore, the fuzzy image falls on the retina, and the person sees the objects blurred.
Causes of
At present, scientists have formed a rich collection of observations of such a complex phenomenon as myopia. In this case, it was possible to establish some of the causes of myopia:
- Excessive visual stresses, leading to overexertion of the organs of vision. It can be reading under bad light, long work at the computer or watching TV for a long time.
- Hereditary predisposition. According to statistical data, in 50% of cases, children whose parents were nearsighted, up to 18 years of age, this visual impairment also manifests itself. If myopia was only in one parent, then the percentage is reduced to 20-25%.If parents had normal vision, children suffer from myopia in only 8% of cases. Such observations made it possible to conclude that heredity can act as a cause of myopia.
- Hemodynamic disorders - insufficient blood supply to the eyes, weak blood circulation in the inner shells of the eye, disturbance of the orbital and central blood flow.
- Unbalanced power supply. For the normal synthesis of the eye tissues, a constant intake of useful trace elements, such as zinc, copper, chromium, is necessary. Their shortage can be considered as a reason for myopia.
Scientific notions of myopia
In order for eyesight to be possible, the human eye catches light rays reflected from various surrounding objects. Inside the eye they are refracted in such a way as to focus the ideal image on the retina. The light rays coming from distant objects have a practically parallel direction. In myopia, the eye is resized and processes such rays with distortion. The image is formed in front of the retina. The rays from the nearest objects have a divergence in the direction of motion. They are handled by the eye normally.
"In consolation to the living. .."
Some scientists believe that myopia is a biological variant of normal functioning under conditions of ever increasing loads on the organs of vision. Eyes adjust to work at close distances with minimal stress. And this is an occasion for optimism, is not it? Such are the ideas about the essence and the main views on the causes of myopia.