Useful Information for
Patients awaiting Corneal Transplants
The cornea is a thin, clear layer of the eye that covers the iris (the coloured part of the eye) and the pupil. It looks just like a contact lens and it is the size of a 1 cent piece. It is a vital part of the eye. Light first penetrates the corneas, becomes focused by the lens, and is then projected onto the retina where the stimulation becomes interpreted as a visual picture by the brain. Should the cornea become cloudy from disease, injury or any other cause, vision will become dramatically reduced and sight can be lost. Severe damage of the cornea also impairs the protection of the eye from the drying environment and from infection.
A corneal transplant is a delicate, micro-surgical procedure that replaces a disc segment of an injured or diseased cornea with a similarly shaped piece of healthy donor cornea.
Adults, children and even babies need transplants for a variety of reasons.
A transplant may be necessary because of cornea failure due to:
- Hereditary problems such as Fuchs’ dystrophy or keratoconus (thinning and steepening of the cornea).
- Scarring after injury, ulceration or infection.
- Ageing processes may affect the clarity and health of the cornea.
- Corneal disease.
There is no substitute for corneal tissue, so corneal transplants rely solely on corneal donation.
Corneal tissue is obtained through an Eye Bank. The Eye Bank is a registered non-profit organisation, authorised by the Dept. of Health to obtain and distribute eye tissue to ophthalmologists for transplant purposes.
Donor corneas are recovered from the deceased, following family consent within 12 hours of death.
The Eye Bank screens the donors for transmittable infections such as HIV and hepatitis.
Once a decision is made that you need a corneal transplant, your name is put on a computer database at the local Eye Bank. The wait for a cornea depends on your age-compatibility with the available donor
tissue and your degree of visual handicap.
Your Ophthalmologist may request that you undergo a physical examination and perform other tests to determine whether you have any medical conditions that might affect the surgery. It is also important to discuss with your surgeon any medication that you are currently taking.
What happens? The Surgery may be performed under a general anaesthetic (with you asleep) or under local anaesthetic (the eye is numbed). The surgeon removes a circular piece of your cornea and replaces it with the donor cornea that is then stitched into place with very fine sutures. The surgeon uses a surgical microscope for precision.
How long does it take? It usually takes 1-2 hours
What happens to the old Cornea? Most corneas are examined under a microscope for further information. Damaged corneas are disposed of in the hospital theatre. Some tissue may be kept for research into corneal disease.
How long do I stay in hospital?
Most patients stay in hospital 0-3 days so they can get regular eye-drops, pain relief medication , & so that the eye can be observed. You will need to organise transport home from the hospital as it could be unsafe for you to drive.
Will there be pain?
Most patients do experience some pain and discomfort, but this is usually relieved by over the counter pain medication. Your eye may be swollen and irritated for the first couple of weeks, and some people experience an occasional scratchy feeling or sharp pain when moving the eye. If pain persists over a period of six to twelve hours, or recurs you should contact your ophthalmologist.
When are the stitches removed?
Your ophthalmologist will decide when to remove the stitches, usually after 6 months.
Vision after the operation:
Your vision may be poor for some time after the surgery. During the first few weeks, the cornea may be unclear and a bit irritated. As it heals and stabilises, you will experience visual improvement. Your vision may fluctuate from time to time; however, significant worsening of the vision should be reported to your doctor. Because the new cornea may be a different shape from the old cornea, your glasses or contact lens prescription may change. You may also find that your prescription changes more than once as your eye heals.
Usually your first follow-up visit will be scheduled for the day after surgery, when the doctor will remove the eye patch and check your new cornea. They will also prescribe special steroid eye drops to help prevent your body from rejecting the transplant. The eye patch will remain in place for 1 – 4 days after surgery. You can expect to have several follow-up visits during the first two weeks. Once it is clear that your eye is healing as expected, your doctor will schedule follow-up visits at longer intervals.
The most common complication of corneal transplantation is rejection of the new cornea. Rejection occurs because the body’s immune system identifies the donor cornea as “foreign” tissue and begins to attack it. Rejection occurs in about 5 – 30% of corneal transplants. In most cases (90%) it can be treated successfully with medication if it is detected early. There are four signs of rejection that can be remembered by the mnemonic “RSVP“: Redness, Sensitivity to light, decreased Vision, and Pain. Any of these four symptoms, experienced after the initial healing period, must be reported to your ophthalmologist immediately.
Although most corneal transplants are successful, the risks of the transplant procedure include bleeding, infection, broken sutures and anaesthetic side effects. In addition, since transplantation opens the front of the eye, there is some danger that eye fluid may leak out of the eye after surgery. There is also a slight risk that fluid pressure inside the eye will become abnormally high or low, or that the retina may separate from the back of the eye. All these problems are rare.
The cornea itself is free as it is a gift of sight from the donor, but there is a charge for the service and costs incurred by the Eye Bank and for the operation itself. If you are receiving a corneal transplant through a provincial hospital, the cost will be covered by the admission fee which depends on your level of income. If you are on medical aid, most schemes cover the cost, but it is always advisable to discuss this with your medical aid consultant.
If you would like to, you are encouraged to write a letter of thanks (with only your first name on it) to the donor’s family. You can drop this letter off with the Eye Bank or email or post it to them and they will deliver it to the donor’s family.