The cornea is the outer, clear, round structure that covers the colored part of the eye (iris) and the pupil. The cornea directs light rays into the eye and helps focus them on the light-sensitive retina at the back of the eye, providing sharp, clear vision.

Vision problems such as astigmatism or nearsightedness (myopia) are often caused by changes in the normal shape of the cornea.

Current as of: September 9, 2014

Author: Healthwise Staff

Medical Review: Kathleen Romito, MD - Family Medicine & Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology