Astigmatism is a condition in which light is incorrectly refracted on to the back of the eye, or the retina, due to an irregular curvature of the cornea or abnormalities in the lens of the eye. The ideal eyeball is perfectly round like a basketball, however, in many cases the eyeball may be more oblong, or shaped like a football. When the eye is mis-shapened in this way, only part of an object is in focus. Vision may be distorted or blurred at all distances.
The cause of astigmatism is not known but it is believed to be related to genetic factors. It can be easily fixed with glasses, contacts or refractive surgery that changes the shape of the eye. Astigmatism can be easily diagnosed with an eye exam.