To understand the causes of myopia and it happens, one must look in the eye and the way it works first. Eyes more like an integrated system allows the vision, and eye lenses include the headlights, the cornea, the internal crystalline lens. And function of all these elements that combine image on the retina and then send an electrical signal to the brain to translate the image and analysis. But this system can suffer from a clear defect called mistakes refractive index, results in vision problems such as nearsightedness, farsightedness and astigmatism.
What is myopia?
Myopia is a vision defects afflicting nearly 30% of people in any society, which is about the difficulty of seeing the details of distant objects while nearby can see the details clearly. In this case, the front lenses are stronger than normal rates, both up convexity of the cornea regular conditions or pathological conditions, as in the case of the cornea Almkhtootah, or increased eye length than normal, which is 24 Mellmitr, to form the image inside the eye away from the vision center, resulting it blurred and blurred vision from afar, what is known as myopia. There are two types of this disease, myopia false and the Palace of the real view.
Palace false consideration
Most cases of short-sighted among adolescents belong to the false palace, when you see things from close range for a long time, this will increase the intensity of tension eye ball, causing Chnjha, dizziness and deterioration of view.
Palace real consideration
If you do not solve the problem of false myopia and remained eyeball in the case of constant tension, it will lead to the real palace of view. If the eye has worked for a long time, can not sit back muscles, causing nearsightedness. The real reason for the decline is a short-sighted eye's ability to edit itself, causing ambiguity of images on the retina. In order to clarify these images, the eye must extend the axis of the eye, and it increases the severity of myopia.
Palace considered severe or high grades
Is myopia in excess of 6 degrees, where the patient is suffering from severe weakness accompanied by changes in the private retinal eye as a result of an increase in the size of the eye along the natural rates that are at a rate of 22-24 Mellmitr, but in cases of palace of the high considering more than 27 Mellmitr This entails weakness in the retina.