The cornea is the crystal clear portion of the surface of the eye that lets light enter. The cornea is well supplied with nerve endings which is why some people can never get used to wearing contacts.
Review Date 8/28/2018
Updated by: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.