Astigmatism

Astigmatism is a refractive error which causes blurred or distorted vision. It is one of the most common vision problems. Astigmatism usually occurs when the front surface of the eye, the cornea, has an irregular curvature.

This irregular shape prevents light from focusing properly on the back of the eye, the retina. As a result, a person's vision may be blurred at all distances. Normally the cornea is smooth and equally curved in all directions. With astigmatism, the cornea is "warped", meaning it curves more in one direction and objects appear somewhat indistinct and slanted.It can occur with or without shortsightedness or long-sightedness.