AK

The cornea and lens combine to focus visual images on the back of the eye. When the overall shape of the eye is incorrect or when the curvature of the cornea is incorrect, the visual images are not in focus. The cornea accounts for approximately 2/3rds of the focusing power of the eye. By surgically changing the corneal curvature, most or all of the blur can be overcome.

Astigmatic Keratotomy (AK) is used to help people with astigmatism. Astigmatism is an uneven curvature of the cornea. It is curved more in one direction than the other, causing a distortion in vision. During AK, one or more surgical incisions are made in the cornea. These incisions help eliminate the uneven curvature and "round out" the cornea. A rounder cornea means objects no longer appear blurred or distorted. AK is sometimes performed at the time of cataract surgery, in order to reduce or eliminate the patient's preexisting astigmatism.