When your cornea is damaged due to injury or disease, a corneal transplant may be able to restore or dramatically improve your vision. Performed as an outpatient procedure, most corneal transplants have a favorable outcome, and success rates are rising as techniques improve.
The cornea is the clear, dome-shaped surface of the front of the eye. The cornea, along with the eyelids, eye socket, tears, and white part of the eye (sclera), helps to protect your eye from dust and germs. It also permits light to enter your eye.
Your corneas can quickly heal minor injuries and scratches before you experience infection or visual disturbances. However, deep injuries can permanently damage your vision. A corneal transplant (keratoplasty) is a surgical procedure that replaces a damaged or diseased cornea with healthy tissue from a donor.
About 40,000 corneal transplants are performed each year in the United States, according to the National Eye Institute (NEI).
Where Does the Donor Corneal Tissue Come From?
The corneal tissue comes from a registered tissue donor who has recently died. Because almost everyone can donate their corneas after they die, the waiting list is usually not as long as for organ transplants. The tissue generally comes from an eye bank and will be tested prior to transplantation to make sure it is safe for you.
Patients who are not good candidates for transplantation with donor tissue may be candidates for an artificial cornea transplant. Although donor tissue tends to bring about the best results for the majority of patients, people who have either severe ocular surface disease or have had more than one failed graft in the past may be better suited to an artificial transplant.
Why Is a Corneal Transplant Performed?
A corneal transplant can restore or dramatically improve vision in someone who had a damaged or diseased cornea. It may be performed to treat:
- Fuchs’ dystrophy
- lattice dystrophy
- a cornea that bulges outward
- thinning of the cornea
- cornea scarring, clouding, or swelling
- corneal ulcers
How Should I Prepare for a Corneal Transplant?
Before scheduling a corneal transplant, you will need a thorough eye exam. A doctor will take exact measurements of your eye and treat any unrelated eye problems that may affect your surgery.
Tell your doctor about all your medical conditions and any prescription medications and over-the-counter medicines you take. You may be advised to stop taking medications that interfere with clotting of the blood.
Prior to the day of surgery, ask your doctor for specific preparation instructions for your procedure. These may include:
- no eating and drinking after midnight on the night before surgery
- wearing loose, comfortable clothing on the day of the procedure
- keeping your face free of makeup, creams, lotions, and jewelry
- arranging for someone to drive you home after the procedure
What Happens During a Corneal Transplant?
You will probably remain awake during the transplant, but you may receive a sedative to help you relax. A local anesthetic will be injected around the eye to prevent pain and to keep your eye muscles from moving.
The surgery is performed using a microscope. Your surgeon will remove a small, round piece of your cornea with a cutting instrument called a trephine.
The new cornea, cut to fit, is set in place and sewn in with ultra-fine thread that remains in place until the eye is completely healed. (Later, this thread is easily removed in a doctor’s office.)
The procedure takes approximately one to two hours, with an additional hour or two in the recovery room.
What Happens After a Corneal Transplant?
Right After Your Surgery
You will be able to go home the same day as your surgery. You may feel some soreness and will most likely wear an eye patch or gauze over the affected eye for up to four days. Do not rub your eyes. Your doctor will prescribe eye drops and, in some cases, oral medications to help with healing and to prevent rejection or infection.
Seek medical attention immediately if you experience any of these symptoms:
- shortness of breath, coughing, or chest pain
- fever and chills
- nausea or vomiting
It is possible that your vision will become worse for several months as your eye adjusts. The thread used during the surgery will be removed after healing is complete. You will always need to take extra precautions to avoid injuring your eye during exercise or sports. You should continue to have regular eye exams as advised by your doctor.
Most people experience at least partial restoration of their sight, and some will continue to require prescription eyewear. Full recovery may take up to a year, but recovery times are decreasing as techniques improve.
What Are the Risks of Corneal Transplant?
Corneal transplant is a relatively safe procedure, but risks include:
- clouding of the lens (cataracts)
- increased pressure in the eyeball (glaucoma)
Your body may reject the transplanted tissue. Approximately 20 percent of patients reject their donor corneas, according to the National Eye Institute (NEI). A study supported by NEI suggests that in high-risk patients, this rate may be improved by matching blood type rather than tissue type.
In many cases, rejection can be controlled with steroid eye drops. The risk of rejection decreases over time, but it does not completely go away.
Warning signs of rejection include:
- decreasing vision
- increasing redness of the eye
- increasing pain
- increasing sensitivity to light
If you experience any of these warning signs, it is important to seek prompt medical attention.