Corneal Transplants

About Corneal Transplants

The cornea is the clear dome shaped layer at the front of the eye, responsible for focusing light through the eye. When this tissue becomes compromised by disease, infection or trauma, a surgical procedure called Corneal Transplantation, or Corneal Graft, can be performed. This involves the removal of unhealthy or diseased corneal tissue, and replacement with healthy donor corneal tissue.

There are several conditions which may result in the need for a corneal transplant, including:

  • Fuch’s Endothelial Dystrophy
  • Pellucid Marginal Degeneration
  • Terrien’s Marginal Degeneration
  • Keratoconus
  • Ocular surface scarring
  • Corneal Trauma/Injury/Infection

Surgery Techniques

Full Thickness Penetrating Keratoplasty

Some patients require the full thickness of their cornea to be replaced. This procedure is called a Penetrating Keratoplasty, where the central unhealthy cornea is essentially punched out and the donor cornea is stitched in its place. Two continuous running sutures hold the graft in place. The first stitch is removed around three months after the surgery, with the second stitch removed around 12 months after the surgery. This means it can take over 12 months to stabilise post-operative vision.

The Eye Health Centre - Corneal Transplants

Partial Thickness Corneal Transplants

The cornea is made up of three layers of tissue, and certain corneal conditions may only affect one or two layers of the cornea. As a result, advanced surgical techniques exist which can replace only the diseased or unhealthy layer of the cornea. By keeping some of the patient’s original healthy corneal tissue, rejection rates are reduced, healing time is expedited, and vision outcomes are improved.

At The Eye Health Centre, Descemet’s Membrane Endothelial Keratoplasty (DMEK) is the preferred Partial Thickness Surgical Technique. Despite being the most difficult surgery to perform, this corneal transplant option has the most benefits for patient recovery and visual outcomes.

Descemet’s Membrane Endothelial Keratoplasty (DMEK)

DMEK is the most advanced surgical technique in replacing corneal tissue, where the layer of tissue replaced is only 10-15microns thick. This procedure is suitable for patients with diseased or compromised corneal tissue that is limited to the posterior, or back layer of the cornea only. DMEK is a suture-less procedure, with the donor tissue held in position by an air bubble placed inside the eye during surgery. As this surgical technique is the least invasive, visual recovery is much quicker than other surgical techniques. It also has the lowest rejection rate of all corneal surgery transplant techniques.

The Eye Health Centre - Corneal Transplants

Full Thickness Penetrating Keratoplasty

Some patients require the full thickness of their cornea to be replaced. This procedure is called a Penetrating Keratoplasty, where the central unhealthy cornea is essentially punched out and the donor cornea is stitched in its place. Two continuous running sutures hold the graft in place. The first stitch is removed around three months after the surgery, with the second stitch removed around 12 months after the surgery. This means it can take over 12 months to stabilise post-operative vision.

The Eye Health Centre - Corneal Transplants

Partial Thickness Corneal Transplants

The cornea is made up of three layers of tissue, and certain corneal conditions may only affect one or two layers of the cornea. As a result, advanced surgical techniques exist which can replace only the diseased or unhealthy layer of the cornea. By keeping some of the patient’s original healthy corneal tissue, rejection rates are reduced, healing time is expedited, and vision outcomes are improved.

At The Eye Health Centre, Descemet’s Membrane Endothelial Keratoplasty (DMEK) is the preferred Partial Thickness Surgical Technique. Despite being the most difficult surgery to perform, this corneal transplant option has the most benefits for patient recovery and visual outcomes.

Descemet’s Membrane Endothelial Keratoplasty (DMEK)

DMEK is the most advanced surgical technique in replacing corneal tissue, where the layer of tissue replaced is only 10-15microns thick. This procedure is suitable for patients with diseased or compromised corneal tissue that is limited to the posterior, or back layer of the cornea only. DMEK is a suture-less procedure, with the donor tissue held in position by an air bubble placed inside the eye during surgery. As this surgical technique is the least invasive, visual recovery is much quicker than other surgical techniques. It also has the lowest rejection rate of all corneal surgery transplant techniques.

The Eye Health Centre - Corneal Transplants
The Eye Health Centre - Corneal Transplants
The Eye Health Centre - Corneal Transplants

What is the risk of rejection?

All organ donor surgeries come with a risk of the host rejecting the donor tissue, and this is also the case with the cornea. Fortunately, rejection rates for corneal transplants are extremely low at less than 5%. Steroid and Antibiotic eye drops are prescribed following surgery to ensure optimal healing of the tissue and acceptance of the donor tissue. Some patients can be more prone to rejection, particularly if they have a larger graft, a repeat transplant, a history of recurrent viruses that affect the eye, or previous episodes of rejection or inflammation . In general, most patients can achieve great vision once the healing process is completed.

Donor Corneal Tissue

Donor corneal tissue is received from the QLD Eye Bank, where all corneal tissue is screened to ensure it meets strict criteria for transplantation. Persons who wish to be an organ donor must register with the Australian Organ Donor Registry. Approximately 600 corneal transplant surgeries are performed in QLD every year. Without the kindness of these donors, this sight saving surgery would not be possible.