A cornea transplant, or graft, is only an option for those with very advanced Keratoconus, or for those who have a particularly vicious episode of Corneal Hydrops. It is for patients who have exhausted all other options and their only option remaining is to replace the cornea.
*To hear from someone who has gone through a corneal graft, click here to read Johan’s excellent account.
By replacement cornea, doctors actually mean a donor cornea from a deceased person. For those facing the real possibility of an operation, the thought of ‘dead man’s eyes’ as my brother put it, is an uncomfortable one.
JUST 0.6MM THICK
However, you have to get past the initial squeamishness of the thought and look at the facts. The cornea is only 0.5-0.6mm thick and 11.5mm in diameter. This is a tiny jumble of cells, not your entire eye. I think of it as a layer of skin. Compare it to an organ transplant and you get some sense of the scale.
Moorfields Eye Hospital has a very good section on Corneal Graft surgery, from which I have borrowed this:
Patients undergoing a corneal graft operation are admitted to a ward the day of their operation and discharged home on the same day.
Checks such as urine tests, blood tests and sometimes an electrocardiogram (ECG) are carried out to make sure you are in good health for the general anaesthetic.
Your surgeon will carry out the operation with the help of a microscope. For a full thickness graft, a central piece of poor cornea is cut through and removed from your eye. It is replaced by clear cornea removed in the same manner from the donor eye. This is then sewn in place with very fine stitches which are removed 1-2 years later. The operation takes about an hour, and is carried out under either general or local anaesthetic.
Simple eh? Not really. But the operations are now routine, with 2,365 in the UK from April 2003-March 2004. Like any operation of this kind, the danger of the body rejecting the donor tissue is always present.
AFTER THE OPERATION
Again I borrow from Moorfields for information about what happens after an operation, as I do not have any first-hand experience myself.
After the operation, the operated eye only will be covered with an eye pad and protective plastic eye shield. As the anaesthetic wears off, some discomfort may be felt in and around the operated eye. If you feel any pain, ask for medicine for relief of any pain or sickness. You may resume normal activities when you feel able to do so. You will be shown how to instil eye drops safely and correctly prior to your discharge.
The day after the operation the eye pad is removed. Your sight will probably be blurred; your eye may water and be uncomfortable in bright light. You will be asked to return to the hospital in the next day or two. The nurse and your ophthalmologist will examine your eye.
Your ophthalmologist may ask you to put in eye drops for six months or more after the operation. It is essential the eye drop treatment is continued exactly as instructed until the end of the course. This is very important because it helps prevent infection and rejection.
You will be given a protective plastic eye shield to wear when sleeping for about two weeks after the operation. You should avoid any risk of a direct blow on your operated eye. You may find that you are sensitive to light and a pair of plain dark glasses, which can be bought cheaply at any chemist, should help. Ask your ophthalmologist when you may return to work or pursue sports especially swimming.
Uncomplicated cases can expect to attend about seven times in the first year after surgery and once or twice in the second year. Patients may be discharged from follow-up after the stitches have been removed, usually 1-2 years after the operation. Stitches are removed at outpatient clinic examinations. However, even after discharge you should be aware that rejection episodes may occur which require urgent treatment.
Ah, rejection. This is where, for me, it gets scary. Rejection basically means the body’s defences attack the donor tissue as it is identified as foreign. If this is going to happen, it is most likely that it will be in the first year after an operation, after removal of the stitches, or as a result of eye infections or injury. Saying that, you are never fully clear of the danger that it may be rejected.
Fortunately, if you notice the symptoms of rejection (decrease in sight, red eye, or pain) in time, a possible rejection can generally be controlled if you get to a hospital quickly. If the cornea is rejected, though, you face a second operation, this time with less chance of a successful outcome, as the scar tissue left in the eye after an operation makes things difficult. As a result, multiple operations (beyond three) are discouraged, though I have heard of a patient who had five operations.
Rejection statistics are changeable depending on who you talk to. When I was offered the chance to have a transplant, I was given the statistics of a 80% success rate in the first five years, a 70 % success rate thereafter. Since then, I have heard that there is a 95% success rate. But ‘success’ is relative to the patient’s opinion. As Johan points out below, there seems to be no definitive statistic on rejection.
A transplant is a very personal decision to take. Some take up the option as soon as it is offered and never look back, wondering why they never did it sooner; some take it up straight away and end up regretting their decision when something goes wrong and they are left with worse vision than before. Others, like myself, decide to pursue all the options available (mainly lens options) before taking the decision to have an operation.
There is no one right answer. Each person has to weigh up the risks and judge the pros and cons based on their own experience. I would advise talking to your doctors, opticians, and lens specialists, as well as your family and friends, before making a decision. There are often options unexplored that may work for your case and getting a wide range of opinion is essential.