Corneal Transplant Surgery
A corneal transplant (penetrating keratoplasty, or PK) is a technique in which the entire thickness of the cornea is removed and replaced with a healthy cornea from a human donor. Corneal transplant surgery can be done either over the entire cornea (total keratoplasty) or over a portion of the cornea (partial keratoplasty).
The cornea is the clear tissue on the front of the eye that covers the iris and pupil. It works with the lens to provide focusing power to the eye. When the cornea becomes opaque, swollen or scarred, vision suffers. Medication is usually the first treatment for controlling the damage. In cases where medication is not reducing or stopping the damage, the next treatment considered is a corneal transplant.
Corneal transplant surgery removes the damaged tissue and replaces it with a healthy, donated human cornea. Because the corneal transplant procedure is a transplant of foreign tissue into the eye, the greatest risk is that the recipient's immune system will reject the tissue. Drugs can be used to suppress the rejection reaction both before it occurs and even after the rejection reaction happens. Despite the availability of immunosuppressive drugs, there is a corneal transplant rejection rate of five to 30 percent.
Corneal transplant surgery is performed in one to two hours as an outpatient procedure. Vision returns slowly after the operation and continues to improve for as long as one year after the surgery. Vision can be dramatically better compared to pre-surgery vision, especially if there are no other conditions to complicate the recovery.