The cornea is the clear window in the front of the eye that covers the colored iris and the round pupil. Light is focused while passing through it, allowing us to see. If it is damaged it may become swollen or scarred, distorting our vision.When vision becomes difficult or painful, disease, injury, infection, previous eye surgery or other problems can cause damage. A transplant is needed if medications or special contact lenses cannot successfully heal or relieve vision problems. The cornea also plays a key role in vision. As light enters the eye, it is refracted, or bent, by the outside shape of the cornea. The curvature of this outer layer helps determine how well your eye can focus on objects close up and far away. If the cornea becomes damaged through disease, infection, or injury, the resulting scars or discoloration can interfere with vision by blocking or distorting light as it enters the eye.
There are three main layers of the cornea:
A corneal transplant is used when vision is lost because the cornea has been damaged by disease or traumatic injury, and there are no other viable options. During the cornea transplant (also commonly referred to as keratoplasty), a patient’s diseased or damaged cornea tissue is actually surgically replaced with the cornea from a human eye of a recently deceased person. The corneas used in these surgeries will come from eye banks that store and collect corneas for this very purpose. Cornea Transplant surgery is painless due to the administration of a local anesthetic at the beginning of the procedure. Some patients may be given general anesthesia, particularly if their overall medical condition is in question. During the corneal transplant surgery, the diseased or damaged cornea is carefully removed from the eye. The new donor cornea is then sewn into place. Most pain medicine should be able to control any residual pain during the recovery period. Recovering from a corneal transplant may take some time. It is certainly not as easy as recovering from LASIK eye surgery.
The stitches will remain in the eye for six to twelve months after the surgery. Eye drops will have to be used while the stitches are in place to assure proper healing and low doses of steroid eye drops are often prescribed on a permanent basis to prevent rejection.
Damage to the cornea may arise from various reasons such hereditary issues, chemical burns, blunt object trauma, viruses or bacteria. Conditions that may require a patient seek a cornea transplant involve, clouding of the cornea, keratoconus, fuchs dystrophy, irregular corneal surface tissue growths, or corneal swelling.
Dr. Daryl R. Pfister is a Board Certified Ophthalmologist who specializes in the medical and surgical management of cataract, cornea, and external diseases of the eye. Dr. Pfister completed a two-year fellowship at the University of Minnesota in Minneapolis and has expertise in corneal transplantation, DSAEK (partial corneal transplants), and cataract surgery. His research has been supported by several grants, presented at national ophthalmic meetings and published in several journals. Dr. Pfister is Southwestern Eye Center's corneal specialist.