What is the cornea?
The cornea is the clear, protective outer layer to the eye. When light enters the eye, the cornea is able to refract, or bend the light, allowing us to see. A clear and healthy cornea is a key factor in maintaining good vision. An injury or disease can affect the cornea causing damage or scarring and affecting one’s ability to see clearly.
Common eye problems that can damage the cornea:
- Keratoconus, where the cornea is cone-shaped rather than dome-shaped
- Fuchs’ corneal dystrophy, where cells in the inner layer of the cornea are not working effectively
- Eye infections or injuries that scar the cornea
- Previous corneal surgery or other eye surgery that damaged the cornea
What is a corneal transplant?
A corneal transplant, also called a keratoplasty, is a surgical procedure to replace a damaged cornea with a healthy donor cornea. If damage from an injury or disease cannot be healed or repaired, your ophthalmologist may recommend a corneal transplant.
Corneal transplants can vary depending on the needs of the patient whether they require only a portion of the cornea or the entire cornea to be replaced. Corneal transplants are the most successful transplant of tissue in the human body.
A penetrating keratoplasty (PKP) is when the full thickness of the central cornea is replaced. It is required in some cases where multiple layers of the cornea have been damaged. Sutures are used to secure the new cornea to the patient’s eye and often may be removed or adjusted as the eye heals.
Selective corneal transplantation offers several advantages over penetrating keratoplasty. If the endothelium (or inner layer of the cornea) is damaged, as in Fuchs’ dystrophy or damage from previous surgery or injury, an endothelial keratoplasty (EK, DSAEK, DSEK, or DMEK) is typically performed. The advantage is faster healing and less risk with a much smaller incision.
If the outer layer of the cornea is damaged but the endothelium is preserved, an anterior lamellar keratoplasty (ALK, DALK) may be recommended. The advantage is long term graft survival without the risk of rejection or need for chronic steroid eye drops.
Your corneal specialist will discuss which option would be best suited for your particular case.