When an injury or disease damages your cornea, a corneal transplant may be able to restore or dramatically improve your vision. A corneal transplant is an outpatient procedure. Most corneal transplants have a favorable outcome, and success rates are rising as techniques and training methods improve.
The cornea is the clear, dome-shaped surface of the front of the eye. The cornea along with the following helps protect your eyes from dust, germs, and foreign particles:
- eye socket
- white parts of the eye, or sclera
The cornea also permits light to enter your eye.
Your corneal tissue 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, or keratoplasty, is a surgical procedure that replaces a damaged or diseased cornea with healthy tissue from a donor.
Doctors perform about 40,000 corneal transplants per year in the United States, according to the National Eye Institute (NEI).
The corneal tissue comes from a recently deceased, registered tissue donor. Because almost everyone can donate their corneas after they die, the waiting list is usually not as long as for other major organ transplants. The tissue generally comes from an eye bank and will undergo testing before transplantation to make sure it’s safe for you.
If you aren’t a good candidate for transplantation with donor tissue, you may be a candidate for an artificial cornea transplant. Donor tissue tends to bring about the best results for the majority of people. However, an artificial transplant may be more successful for people who either have severe ocular surface disease or have had more than one failed graft in the past.
A corneal transplant can restore or dramatically improve vision if you have a damaged or diseased cornea. It may treat:
- Fuchs’ dystrophy, which is a degeneration of the innermost layer of cornea
- lattice dystrophy
- a cornea that bulges outward
- a thinning of the cornea
- cornea scarring, clouding, or swelling
- a corneal ulcer, which is often caused by trauma, such as a scratched cornea
Before scheduling a corneal transplant, you’ll need a thorough eye exam. Your 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 need to stop taking medications that interfere with blood clotting.
Before the day of your 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
You’ll probably remain awake during the transplant, but you may receive a sedative to help you relax. Your surgeon will inject local anesthetic around the eye to prevent pain and to keep your eye muscles from moving.
The surgery involves using a microscope. Your surgeon will remove a small, round piece of your cornea with a cutting instrument called a trephine.
Your surgeon will place your new cornea, cut to fit, and will sew it in with an ultra-fine thread that remains in place until your eye completely heals. Your doctor will easily remove this thread later.
The procedure takes approximately one to two hours. You’ll spend an additional one or two hours in the recovery room.
You’ll 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. Don’t rub your eyes. Your doctor will prescribe eye drops and possibly 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
- chest pain
- a fever
Corneal transplant is a relatively safe procedure, but its risks include:
- clouding of the lens, or cataracts
- increased pressure in the eyeball, or glaucoma
Your body may reject the transplanted tissue. Approximately 20 percent of patients reject their donor corneas, according to the NEI.
In many cases, steroid eye drops can control rejection. The risk of rejection decreases over time, but it doesn’t completely go away.
Seek medical attention right away if you experience any of these warning signs of rejection:
- decreasing vision
- increasing redness of the eye
- increasing pain
- increasing sensitivity to light
It’s possible that your vision will become worse for several months as your eye adjusts. Your doctor will remove the thread used during the surgery after healing is complete. You’ll 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.