Corneal Transplantation:

Shiley corneal specialists David J. Schanzlin, M.D. and Stuart I. Brown, M.D. pioneered many advances in modern corneal transplantation, particularly in infants and children. Consequently, patients worldwide in need of a corneal transplant travel to San Diego for Shiley doctors to perform this delicate surgery.

The cornea is the clear front of the eye that covers the colored iris and the round pupil. It acts as a lens that focuses what we see through the pupil. If the cornea is damaged, it may become swollen, loose its smoothness and clarity, eventually, scars may develop that can change the shape of the cornea (figure 1). The scars, swelling or irregular shape cause the cornea to scatter or distort light, resulting in a glare or blurred vision. Furthermore, infections, whether bacteria, fungal, or viral, are frequent causes of severe corneal damage and ulceration. (We can attribute many of these conditions to improper use of extended- wear lenses.) Still, some disorders of the cornea are inherited and can lead to corneal clouding and loss of sight. These are among the variety of reasons over 40,000 cornea transplants are done in the United States each year. Prior to the outpatient surgery, the eye center secures a suitable donor cornea through a local eye bank. However, before a cornea for transplantation is released, the eye bank tests the human donor for the viruses that cause hepatitis and AIDS, as well as other conditions. The operation is painless, as either local or general anesthesia is used, depending on the patient's age and medical " condition. The surgeon skillfully uses an instrument called a trephine (figure 2) to remove the diseased or injured cornea and to cut out a similar "button" from the donor cornea (figure 3). The surgeon then places the donor cornea button in the round hole of the patient's cornea. Finally, the clear donor cornea is sewn into place (figure 4). While the surgery is one of the most successful transplant surgeries performed in this country, a successful corneal transplant requires care and attention by both patient and physician. The ophthalmologist follows the patient closely after the surgery for several months, as it generally takes this amount of time before the patient's vision stabilizes.