A cornea transplant (keratoplasty) is a surgical procedure to replace part of your cornea with corneal tissue from a donor. Your cornea is the transparent, dome-shaped surface of your eye that accounts for a large part of your eye's focusing power. A number of conditions can be treated with a cornea transplant, including: A cornea that bulges outward (keratoconus) Fuchs' dystrophy Thinning of the cornea Cornea scarring, caused by infection or injury Clouding of the cornea Swelling of the cornea Corneal ulcers, including those caused by infection Complications caused by previous eye surgery Most corneas used in cornea transplants come from deceased donors. Corneas may not be used from donors who had several conditions, such as certain central nervous system conditions, infections, and prior eye surgery or eye conditions, or from people who died from an unknown cause.