Astigmatism (uh-STIG-muh-tiz-um) is a common visual condition in which objects appear relatively blurred at distance and near.
The cornea and lens are responsible for focusing light onto the retina to produce clear images. Normally, the cornea and lens are smooth and curved equally in all directions. This regular shape helps light entering the eye to focus properly.
Astigmatism is present when either the cornea or the lenshas the irregular curvature of a football rather than the spherical shape of a basketball. Uneven curvature of the optical surfaces causes incoming light rays to focus over a range of distances within the eye, resulting in a blurred or shadowed image forming on the retina. Astigmatism frequently accompanies Myopia (nearsightedness) or Hyperopia (farsightedness), vision conditions that are referred to as refractive errors because they affect how the eyes bend or “refract” light.