Astigmatism is the lack of an optical system of the eye. It is formed as a result of unequal curvature of optical surfaces in different planes of section of the incident light beam. Normally, the optical surface must be spherical, as in the case of astigmatism, it is deformed. Therefore, the light beam emanating from a luminous point, after passing through the optical system of the eye is not going to at one point, as it should, and in two mutually perpendicular straight line segments. That's why instead of the normal image, we get something deformed and fuzzy. And the person who suffers from astigmatism, poor vision both near and far. Oddly enough, but the majority of people living on this planet, there is astigmatism. But it's so small, that does not prevent us from seeing things clearly and distinctly. And now about 15% of the population suffer from astigmatism to a greater extent, which creates some problems with his vision.
The cause of astigmatism, as we said above, is a non-uniform curvature. Most often, the cornea is deformed, but the same problem may lie in the lens of the eye.
There are several types of astigmatism.
It may be long-sighted, when a person is worse distinguishes objects up close, short-sighted from a distance when subjects lose their shape. In severe cases, it is a combined astigmatism. In this case, a man equally bad seeing both near and far.
Unfortunately, astigmatism affects not only adults but also children. And kids often get the disease is inherited, in which case it is a congenital astigmatism. Acquired Astigmatism is caused by gross corneal scarring after injuries or operations eye on it.
Not everyone sees your astigmatism. Seeing things blurry or stretched, simply does not give any importance to this. But frequent headaches, fatigue at elevated pressure on the eye such signs can not help but draw attention to themselves. Also, quite often after straining his eyes (watching TV, working at a computer) can occur a symptom such as "flicker flies." All this makes a person seek the advice of an ophthalmologist. Optometrist examines eyes for special tables, and using cylindrical lenses. And just in the course of this survey and found astigmatism.
Treatment of astigmatism has three lines: glasses, contact lenses and surgery.
Glasses and lenses are matched patient individually in each case, taking into account the peculiarities of the eye. For the correction of astigmatism with cylindrical lenses are required. If necessary, they can also be combined with lenses for the correction of farsightedness and nearsightedness. It is important to understand that no glasses or lenses are not a cure and a way to combat the problem. They only correct the vision.
After the selection of glasses or lenses must be constantly observed the doctor, replacing them on his recommendation to the stronger or weaker.
Get rid of astigmatism can be only through the operation (keratotomy, thermal keratosis).
Keratotomy is an operation for applying cuts on the cornea. The result diminished refraction and normal sight. This operation is suitable for patients with mixed astigmatism and myopia.
Termokeratokoagulyatsiya cauterization of the peripheral zone of the cornea. As a result, the curvature of the cornea increases and, consequently, increases its refractive power. This operation is used to treat farsighted astigmatism.