I have received a corneal transplant years ago. The surgery went successful, and not much eye rejection after that. First the Dr would give you a thorough eye examination, and ask about your eye conditions. For instance, do you have eye infection? Are you take drugs recently? Then you would be placed in the wait line. Before the surgery, I got anesthesia around my eyes along with sedation to relax. I was still awake, but there was no pain felt during the procedure. And after that I need to use the eye patch to protect my eyes from stimulaion. The Dr also gave me some meds and other medical advice. Things like eating more fresh veges and fruits, don't take shower in a week and pay attention to your conditions. The eye rejection may happen, and you may lose your sight for days, can't help tearing, get eye infection or inflammation and so on. The two weeks after surgery is the period that requires your attention most. Fortunately there was no discomfort for me. My eyes took it quite well.