Types of Corneal Transplant

 

A Corneal Transplant is a surgical procedure to remove all or part of the diseased or injured cornea and replace it with a similarly sized and shaped part of a healthy donor cornea.

Types of Transplants:

Penetrating or full thickness transplants involve removing the entire diseased or injured cornea from the recipient and replacing it with a healthy donor cornea. In this procedure, sutures are sewn onto the graft to ensure proper placement of the tissue. Usually, a rigid hard contact lens is placed over the graft to simulate better visual potential during the first months post-transplant.

Anterior Lamellar Keratoplasty:

Anterior Lamellar Keratoplasty transplants replace only a section of the diseased or injured cornea instead of the entire cornea such as when a Deep Anterior Lamellar Keratoplasty (DALK) surgery is performed. In this type of procedure, only the front part of the recipient cornea needs to be replaced and not the entire cornea. Because only a section of recipient corneal tissue is removed, the risk of rejection is less likely and the eye is less vulnerable to injury and infection.

Endothelial Lamellar Keratoplasty:

Endothelial Lamellar Keratoplasty occurs when the recipient’s outer cornea is rather healthy; however, the most posterior layer (corneal endothelium) is diseased or injured. In this procedure, only the recipient’s endothelial layer (the back 10%) portion of the cornea is removed and replaced with the back 10% of the healthy donor cornea. The remaining 90% of the recipient cornea remains intact. This procedure is termed Deep Endothelial Lamellar Keratoplasty (DELK). This procedure requires no sutures to keep it in place, allowing the recipient’s graft to heal much quicker, less chance of infection or rejection occurs and less induced astigmatism occurs.

Corneal transplantations are performed for several reasons:

Optical:
To improve the optical qualities of the cornea to improve vision by replacing a scarred cornea with a healthy, clear one.

Reconstructive:
To reconstruct a perforated cornea to preserve the eye in its whole form.

Therapeutic:
To treat a disease unresponsive to medical management such as uncontrolled fungal corneal ulcers or to alleviate the pain of a severe foreign-body sensation due to recurrent ruptured blister-like lesions in Bullous Keratopathy.

Common Indicators for Transplantation

Bullous Keratopathy, Fuchs’ Endothelial Dystrophy, Keratoconus, Repeat Graft, Keratitis, Viral or Bacterial Problems, Fungal Ulcers, Perforations, and Corneal Stromal Dystrophies are the most common indications for a corneal transplant.