The cornea is the clear outer lens on the front of the eye. A corneal transplant is surgery to replace the cornea with tissue from a donor. It is one of the most common transplants done.

Keratoplasty; Penetrating keratoplasty

You will probably be awake during the transplant, but you will be given medicine to relax you. Local anesthesia (numbing medicine) will be injected around your eye to block pain and temporarily prevent eye muscle movement.

The tissue for your corneal transplant will come from a person (donor) who has recently died and who had agreed to donate their tissue. The donated cornea is processed and tested by a local eye bank to make sure it is safe for use in your surgery.

The most common type of corneal transplant is called “penetrating keratoplasty.” During this procedure, your surgeon will remove a small round piece of your cornea. Then your surgeon will sew the donated cornea into the opening of your cornea.

A newer technique called lamellar keratoplasty may be used for some patients. During this procedure, only the inner or outer layers of the cornea are replaced, rather than all the layers. This technique can lead to faster recovery and fewer complications.

A corneal transplant is recommended for people who have:

• Vision problems caused by thinning of the cornea, usually due to keratoconus (when less invasive treatments are not an option)
• Scarring of the cornea from severe infections or injuries
• Vision loss caused by cloudiness of the cornea, usually due to Fuchs' dystrophy

Sometimes, the body rejects the transplanted tissue. This occurs in about one out of three patients in the first 5 years. Sometimes rejection can be controlled with steroid eye drops. However, there is always a risk of rejection.

Other risks for a corneal transplant are:

• Bleeding
• Cataracts
• Infection of the eye
• Glaucoma (high pressure in the eye that can cause vision loss)
• Loss of vision
• Scarring of the eye
• Swelling of the cornea

The risks for any anesthesia are:

• Allergic reactions to medicines
• Breathing problems

Tell your doctor about any medical conditions you may have, including allergies. Also tell your doctor what medicines you are taking, even drugs, supplements, and herbs you bought without a prescription.

You may need to limit medicines that make it hard for your blood to clot for 10 days before the surgery. Some of these are aspirin, ibuprofen (Advil, Motrin), and warfarin (Coumadin).

You may take your other daily medicines the morning of your surgery--but check with your doctor first. Also talk to your doctor if you take diuretics (water pills) or insulin or pills for diabetes.

You will need to stop eating and drinking most fluids after midnight the night before your surgery. You can have water, apple juice, and plain coffee or tea (without cream or sugar) up to 2 hours before surgery. Do not drink alcohol 24 hours before or after surgery.

On the day of your surgery, wear loose, comfortable clothing. Do not wear any jewelry. Do not put creams, lotions, or makeup on your face or around your eyes.

You will need to have someone drive you home after your surgery.

Note: These are general guidelines. Your surgeon may have specific requirements or instructions.

You will go home on the same day as your surgery. Your doctor will give you an eye patch to wear for about 1 to 4 days.

Your doctor will prescribe eye drops to help your eye heal and prevent infection and rejection.

Your doctor will remove the stitches at a follow-up visit. Some stitches may stay in place for as long as a year, or may not be removed at all.

Full recovery of eyesight may take up to a year. This is because it takes time for the swelling to go down. Most patients who have successful corneal transplants will enjoy good vision for many years. But, if you have other eye problems, those problems may still reduce your eyesight.

Often glasses or contact lenses may be needed to achieve the best vision. Laser vision correction may be an option if you have nearsightedness, farsightedness, or astigmatism after the transplant has fully healed.

Blackmon S, Semchyshyn T, Kim T. Penetrating and lamellar keratoplasty. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology. On DVD-ROM. 1st ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2012:chap 26.

Yanoff M, Cameron D. Diseases of the visual system. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 431.