|
Untitled Document
Astigmatism is a vision disorder that occurs when the cornea of the eye is uneven in shape. More rarely, it can result from the way in which the eye's natural crystalline lens refracts light. Either condition causes a distorted image to fall on the retina.
The human eye works much like a camera with two lenses -- the cornea, which is a clear membrane that covers the front of the eye, and the natural crystalline lens, which is located behind the pupil. These two lenses work together to focus light on the retina, which is the membrane that covers the back two-thirds of the eye and works like the film in a camera. A normal cornea should be curved equally in all directions, allowing light to focus exactly on the surface of the retina. Most vision problems result from an irregularity in the curvature of the cornea or in the shape of the eye.
Astigmatism is very common and new eye care products have been popping up in the marketplace to help people with the condition. No one really knows what causes astigmatism. Some are born with it, while others develop it later in life. It can be hereditary. Sometimes people develop the condition after cataract or cornea surgery. Since there isn't a known cause for astigmatism, there isn't a way to prevent it.
Visit the eye doctor regularly. A routine eye exam can determine if you have astigmatism. Special instruments may be used to determine eye diseases. Some symptoms that are associated with astigmatism are nearsightedness, farsightedness, blurry and uneven vision.
Astigmatism can be treated surgically or nonsurgically. Prescription eyeglasses and contact lenses or laser vision correction surgery correct most cases of astigmatism. The most prevalent nonsurgical correction is a prescription for rigid gas permeable (RGP) contact lenses. Because it is rigid, an RGP lens will fill in the irregular areas of the cornea with tears, creating a smooth spherical surface and correcting astigmatism. Special soft contact lenses called torics also compensate for the astigmatic shape of the corneas. In those cases where the astigmatism arises from the eye's natural crystalline lens rather than the cornea, a special bitoric contact lens may be prescribed. It offers refracting surfaces on the front and back to correct the problem in much the same way that eyeglasses do.
If you cannot tolerant contact lenses, not comfortable wearing them, just want to be free from glasses or contacts, you may opt to have some form of vision correction procedure performed by a qualified eye surgeon. LASIK, the most popular form of laser vision correction, can provide correction for relatively high degrees of nearsightedness and astigmatism as well as some cases of farsightedness and astigmatism.
 |
Subscribe to this comment's feed