Most corneal transplant operations are done under local anesthesia on an outpatient basis. This means that the patient is awake but an injection is given to make the eye completely numb. There is no pain.
The corneal tissue for transplantation is taken from a donor shortly after death with the permission of the next of kin. Though most transplant procedures carry the risk of rejection of the transplant tissue or organ, the cornea has very limited blood supply, which greatly reduces this risk. Most corneal transplants function extremely well for many years.
Full visual recovery takes a long time (up to a year), but most patients with successful corneal transplants will enjoy good vision for many years, or even a lifetime.