Corneal Transplantation

The cornea is the front window of the eye.  The cornea is crucially important for allowing good vision because:

  • It allows light to pass into the eye – therefore it must remain clear
  • The curved shape of the cornea helps to focus light on the retina

See “About the Eye” for more information about eye anatomy.

Corneal transplantation is a quite a common procedure in Australia and can help people who have poor vision due to diseases of the cornea. Glasses and contact lenses will usually be tried before a decision is made that a corneal transplant is required.   If adequate vision can be achieved with glasses or contact lenses, a transplant can usually be avoided or delayed.

Numerous diseases may require a transplant. The most common diseases requiring a corneal transplant include:

  • Fuchs’ Endothelial Dystrophy: this is a disease where the inner cell layer of the cornea (called the endothelium) is affected. It causes the clarity of the cornea to be reduced.
  • Keratoconus: this is a disease where the shape of the cornea changes and the cornea takes on a conical shape. Vision is poor primarily due to the abnormal shape of the cornea.
  • Pseudophakic Bullous Keratopathy: this is similar to Fuchs’ Endothelial Dystrophy and can occur after cataract surgery or other eye surgery.
  • Eye trauma: corneal scarring can occur after significant injury to the cornea. A corneal transplant may be required to improve vision.

A corneal transplant refers to the transplantation of a cornea from a deceased donor to use in a patient who requires a transplant to improve vision.  The 4 main types of corneal transplants in use currently are:

  1. PK (Penetrating Keratoplasty): this involves transplantation of the full thickness of the original cornea which is sutured into place with small sutures
  2. DSEK / DSAEK (Descemet’s Stripping Endothelial Keratoplasty): This is a partial thickness transplant where the inner endothelial cells are replaced, along with Descemet’s membrane and some stroma. It is of particular use in patients with Fuchs Endothelial Dystrophy and Pseudophakic Bullous Keratopathy
  3. DMEK (Descemet’s Membrane Endothelial Keratoplasty): Similar to a DSEK, this very modern transplant involves transplantation of only the inner Endothelium and Descemet’s membrane.
  4. DALK (Deep Anterior Lamellar Keratoplasty): This is similar to a PK, except that the inner endothelial cells of a patient are left intact. This technique is commonly used for keratoconus and may reduce the chance of transplant rejection.

DSEK and DMEK surgery are usually performed using sedation and local anaesthetic around the eye (similar anaesthetic to cataract surgery).  For both of these procedures the transplant is placed inside the eye and positioned with an air bubble.  This air bubble is left in the eye after surgery and helps the transplant to attach to the inside of the cornea.  Immediately after surgery you will need to lie on your back staring at the ceiling while the transplant attaches in place. This is usually necessary for about 24 hours.  Your doctor will check the eye pressure and the position of the transplant.  You may require air to be added or removed in the period after surgery.

There are risks with corneal transplantation.  Corneal transplantation is very complex eye surgery and the risks of a significant complication are higher than in many other types of eye surgery.  It is important to have a detailed discussion with your surgeon about the risks of your procedure.

As they are a transplanted organ, corneal transplants are at risk of being “rejected”. This means your body recognises the transplant as foreign and your immune system attacks it. Fortunately, corneal transplant rejection can usually be avoided with the use of anti-inflammatory drops after surgery.  It is important that you diligently use your prescribed drops and contact your surgeon if you develop any eye problems after surgery such as deterioration of vision, eye redness of eye pain.