A cornea transplant is an operation to replace part of the cornea with corneal tissue from a donor. This operation is sometimes called keratoplasty. The cornea is the transparent, dome-shaped surface of the eye. Light enters the eye through the cornea. It plays a large role in the eye's ability to see clearly. A cornea transplant may: Restore vision. Reduce pain. Improve the appearance of a damaged or diseased cornea. Most cornea transplant operations are successful. But cornea transplant carries a small risk of complications, such as rejection of the donor cornea.