Penetrating Keratoplasty

A corneal transplant is performed when the cornea (the clear, front window of the eye) has become cloudy or distorted, resulting in a decrease in vision. The diseased part of the cornea is removed and replaced by a cornea provided by an organ donor.

A penetrating keratoplasty is a full thickness corneal transplant. The donor tissue is held in place with around 16 stitches (sutures) that remain in the eye for 18 months to 2 years before they are removed. After this time, glasses or contact lenses are usually required to optimise your vision.

                        A diagram showing a penetrating keratoplasty held in place by 16 sutures

A penetrating keratoplasty is usually performed under general anaesthetic. After the operation, your eye will feel uncomfortable and light sensitive but you should not be in significant pain. You will be given antibiotic eye drops to reduce the risk of infection for the first month and steroid eye drops to reduce the risk of rejection for the entire time the sutures remain in your eyes. Depending on your type of work, at least 2 weeks off study/ work is recommended.

There are numerous risks including:
• Rejection – it is therefore important that you stay on your steroid eye drops and you come to the Emergency Department if you suddenly develop a reduction in your vision
• Failure – with time, most transplants will fail. The survival rate is up to 89% after 10 years, although this varies depending on the reason for your transplant
• Cataract – a cataract will develop at an earlier age compared to a normal individual due to the surgery and the use of the steroid eye     drops
• Raised eye pressure – an increase in your eye pressure leading to glaucoma can occur due to the steroid eye drops. Careful monitoring of your pressure and treatment with pressure-lowering drops can minimise any long term damage from glaucoma
• Astigmatism – an irregular shape to the front surface of the cornea means that most people will need glasses or contact lenses to achieve their best possible vision
• Infection
• Blindness – the risk of blindness from the operation is very low
It is also important to understand that the junction between your transplant and your own cornea does not regain the same strength as a normal cornea. It is therefore vital that you avoid direct trauma to the eye in the long term as it can cause the edge of the transplant to loosen leading to damage to the internal structures of the eye.