The cornea is the clear front "windshield" of the eye. It is the strongest focusing lens of the eye. Normal vision depends upon the cornea staying clear, thin and smooth. If the cornea should lose its clarity, become swollen or scarred, vision can be limited. In such a situation, medications may be used to try to limit the amount of visual loss. When medicine cannot clear the vision, a corneal transplant is considered. A corneal transplant is an operation in which the cornea is removed and replaced with a healthy donated human cornea.
When an individual dies, his or her family can choose to donate selected organs for transplantation. These donated body parts give people in need a chance at a healthier life. Some of the organs that can be used for donation are the heart, lungs, kidneys, cornea, liver, pancreas and bone marrow.
When the cornea is removed from the donor, it is tested thoroughly to make sure it is safe for transplantation. Tests are done to make sure the cornea has enough healthy cells to make the transplant work. It is tested to make sure the donor did not have any diseases such as AIDS, syphilis or hepatitis that could be transmitted to the recipient. Then, the cornea is placed in a special storage liquid until it is time for surgery.
A corneal transplant is done in an operating room, usually with a local anesthetic. This means that the eye is numbed with a novocaine-like medicine, but the patient is awake. The diseased cornea is removed with a special round cutting tool called a trephine. The donor cornea is cut to a matching size. Then, the donor cornea is placed upon the eye and secured in place with very fine stitches.
A corneal transplant takes many months to heal. Often, the stitches are not removed until six to nine months after surgery. During that time, medicated eyedrops are used to make sure the transplant heals properly.
One of the risks of any transplant is the possibility of rejection. Our body is able to sense things that are not natural parts of it. The body's defense system tries to destroy these foreign tissues. Thus, it is natural for the body to try to destroy a transplant that is foreign because it comes from another person's body. This is the process called transplant rejection. If a corneal transplant rejects, it loses its clarity and swells. Often, corneal transplant rejection can be stopped with medication, but rejection is always a possibility for the rest of the patient's life. If a transplanted cornea is rejected, another transplant may be done.
All surgery has some inherent risks. Many of those risks are beyond the scope of a file such as this. One must always remember that no transplant or surgical procedure can ever be expected to give results as good as the "original equipment", but when serious corneal disease prevents quality vision, a corneal transplant can help to regain much of the lost eyesight.
PLEASE NOTE: The information contained on this system is not intended to supplant individual professional consultation, but is offered as a community education service. Advice on individual problems should be obtained directly from a professional.
Copyright, 1994. Richard E. Gans, M.D.
Last Modified: August 23, 1996