The eye is an optical system where the light rays focus on the retina, creating images. The normal focal length in the human eye is about 23.5 mm, but in some cases there is a violation of this focal length and, as a consequence, problems with vision. The most common such disease is myopia, or as it is called - myopia.
What is medium degree myopia?
In medicine, myopia is divided into three degrees: weak, medium and heavy.
With medium-degree myopia, visual acuity varies from -3 to -6 diopters.
If myopia of a weak degree can not cause special discomfort and in the initial stage not even require wearing glasses or lenses, then with medium degree myopia corrective devices (glasses or lenses) are mandatory. In addition, for a given degree of myopia, two pairs of glasses are often prescribed: one with full correction, for distance, and one for 1.5-3 diopters less for reading and working with closely located objects. Also, starting with an average degree, bifocals are often used: that is, glasses with combined lenses, where in the upper half there are stronger lenses, for viewing distant objects, and at the bottom - weaker ones, for reading.
Myopia of medium degree with astigmatism
Astigmatism is another impairment of vision, which arises from the fact that the cornea has an irregular shape. Therefore, its refractive power can differ, and the rays are focused not in one point, but in several. As a result, objects are distorted and lose clarity. Astigmatism can manifest itself, but often it is observed together with myopia. Moreover, in the presence of myopia, astigmatism can be initially not seen. But if you can not correct myopia with conventional lenses, then astigmatism can occur. In this case, to restore normal visual acuity, special lenses are required, correcting not only nearsightedness, but also this defect.
Treatment of medium degree myopia
To correct nearsightedness by therapeutic methods is impossible. A person can restore visual acuity with the help of special corrective devices: glasses or lenses, but no more. Otherwise, drug treatment, physiotherapy, gymnastics for the eyes are aimed not at treatment, but at maintaining vision and preventing the progress of myopia.
If there is a non-progressive myopia of the middle degree of both eyes, then the vision can be corrected surgically. The most common operation to correct moderate degree myopia is laser vision correction. With the help of the laser, the shape of the cornea changes, which makes it an additional lens and helps to get the right focus.
When vision deteriorates by more than 1 diopter per year, it is said of progressive myopia of medium degree. Such a myopia with time, if not stop its development, goes to a serious degree. If conservative methods stop the development of the disease can not, then resort to prompt intervention, but its goal is primarily to slow the deterioration
Limitations in moderate to moderate myopia
With moderate degree of myopia, sports should be treated more cautiously than with a mild degree. It is desirable to avoid excessive loads, therefore conclusions about the admissibility of certain sports should be taken by an oculist.
Young people who are recruited into the army, with medium degree myopia, are classified in category B and are considered to be of limited use.