Astigmatism is a vision condition that occurs when the front surface of your eye, the cornea, is slightly irregular in shape. This irregular shape prevents light from focusing properly on the back of your eye, the retina. As a result, your vision may be blurred at all distances. People with this condition will usually have blurred or distorted vision, while those with mild cases of this may experience headaches, eye strain, fatigue or blurred vision at certain distances.

Astigmatism can come in combination with nearsightedness and farsightedness. Because of its asymmetrical curvature, the astigmatic eye focuses light correctly along one axis, but incorrectly along the other. Light entering the eye is not focused on a single point on the retina, so objects both near and far become blurred or distorted producing an effect similar to looking through a pane of wavy glass.

Most people have some degree of astigmatism. A comprehensive optometric examination will include testing to diagnose this eye disease and determine the degree. Almost all levels of this condition can be optically corrected with properly prescribed and fitted eyeglasses and/or contact lenses. Corneal modification is also a treatment option for some patients.