A corneal transplant involves the removal of either an entire cornea or portions of it and replacing it with a new cornea taken from a human donor. A corneal transplant is required following corneal disease or significant corneal damage.
We specialise in corneal surgery with our principal surgeon Dr John Males pioneering a number of the newer corneal transplant procedures in Australia.
What is the cornea?
The cornea is a transparent tissue that is dome-shaped covering the front of each eye. It is known as the windscreen of the eye. The cornea is made up of five layers. It normally does not contain any blood vessel and is a clear and smooth surface. It is important that the cornea remains clear to allow light to pass through the eye unobstructed.
When is a corneal transplant required?
A corneal transplant is usually after all non-surgical and minor surgical procedures have been exhausted. It is generally required when:
What are the risks of corneal transplant surgery?
Corneal transplants have a high success rate, but there are potential complications. The risks of surgery include:
Rejection occurs in about 20% of corneal transplants and can happen at any time, even years or decades later. Sometimes a new injury or illness causes the rejection. Fortunately, in most cases rejection can be controlled by medication if treated early enough.
Types of Corneal Transplants
Penetrating Keratoplasty (PK or full thickness)
A full thickness corneal transplantation is where the damaged cornea is removed and a new donor cornea is implanted held in place using very fine stitches.
Descemets’ Stripping Endothelial Keratoplasty (DSEK)
Descemets’ Stripping Endothelial Keratoplasty (DSEK) is a procedure where the diseased endothelial layer of the cornea is replaced rather that the full thickness of the cornea, such as in the case of Fuchs’ Endothelial Dystrophy. The goal is to remove the minimum amount of corneal tissue and replace it with healthy donor tissue to resolve the oedema (or swelling) of the cornea and restore vision.
Advantages of the DSEK procedure include:
Risks of the DSEK procedure include:
As with all transplant surgery, there is a risk of rejection or failure of the transplant in both the early and late stages after the surgery. If this occurs, repeat grafting either with a repeat DSEK transplantation procedure or repeat full thickness corneal transplant may be necessary.
Descemets Membrane Endothelial Keratoplasty (DMEK)
This is the newest type of surgery providing a partial thickness corneal transplant. Only the endothelial cells and the membrane holding the endothelial cells in place are transplanted, which is only about 20 micrometres thick. It is a technique using only a small incision. The patient’s original cornea is left mostly intact, it replaces only the damaged corneal endothelial cells.
Advantages of this procedure include:
Preparing for Surgery
What to expect for your corneal transplant surgery
What to expect during surgery
A corneal transplant is performed in a day surgery and usually takes about an hour depending on the procedure.
Patients are given a sedative to ensure that they remain relaxed throughout the procedure and a local anaesthetic is used to numb the eye. The donor cornea will have been tested to make sure it is healthy and disease or damage-free.
Your surgeon will use a microscope to perform the surgery. Sutures are required and are made of a material that is finer than a human hair.
Afterwards, you will be taken to a recovery room to allow the effect of the sedative to wear off. You’ll then be discharged with eye drops and a protective eye patch. A post-operative check will be scheduled for the following day, and then regularly thereafter.
What to expect after surgery
Following surgery, your corneal tissue will slowly grow and fuse to the donor tissue.
Eyesight recovery is gradual and varies depending on the procedure. For full-thickness transplants, complete recovery can take up to one year. Partial-thickness techniques are less invasive and recovery is generally faster.
Regular post-operative visits allow your ophthalmologist to monitor your progress and identify any complications. Eye drops, and occasionally oral medication, will be required to prevent swelling, infection and pain for at least 6 months.
What to expect with your visual recovery
Generally, corneal transplants are highly successful. Most people experience a considerable improvement in vision. However, glasses or contact lenses are often still required.
Your surgeon may need to adjust the stitches to create a regular and round corneal shape. Stitches can be removed anywhere from 6 months to 3 years later. If the corneal shape is not ideal following stitch removal, then laser eye surgery may be used for further reshaping to improve vision.
It’s important to understand that the transplant will not last forever. How long it lasts depends on the reason for the transplant. For example, a transplant in a patient with keratoconus usually lasts 15 to 20 years.