Astigmatism is a problem of visual distortion caused by a
misshapen cornea. The cornea acts as a focusing lens for the
eye. If the cornea does not have the proper shape, the eye is
unable to properly focus an image. Most people have a certain
degree of astigmatism. Corrective measures are necessary only in
cases where the distortion is severe. Light rays entering a
normal eye come to a point of focus on the retina through a
transparent, dome-shaped layer called the cornea. In astigmatism
there is unequal curvature of the cornea, and the light rays
come to focus at more than one point on the retina. This causes
the person to see a blurred or doubled image. Astigmatism is
usually present at birth and may increase during childhood as
the eye tissue develops. Usually the degree of astigmatism
remains fairly constant throughout adulthood. Causes & symptoms
It is unknown why some people develop a misshapen cornea. It is
possible that astigmatism is an inherited trait. Factors such as
stress, continual reading in di