A corneal transplant can become necessary if non-surgical treatment options have been unsuccessful at managing cornea problems, conditions, or diseases and they have progressed to where vision is compromised beyond an acceptable level. A corneal transplant is a type of eye surgery performed in order to replace diseased, damaged or scarred corneal tissue with new healthy corneal tissue. Since damaged or scarred corneal tissue does not allow light to effectively pass into the eye and reach the retina, poor vision and even blindness may result from a damaged cornea. There are actually a number of different types of corneal transplants that may be appropriate or necessary depending on the condition of your cornea and the degree of vision loss.
Penetrating Keratoplasty (PK) is a type of corneal transplant involves the surgical removal of the entire central area of the damaged cornea. We remove the central portion of the damaged or cloudy cornea with a “cookie cutter” like instrument called a trephine, and replace it with a clear cornea obtained from the eye bank.
We then very carefully sew the donor cornea into place using sutures that are thinner than a human hair. To facilitate the healing of the new transplanted cornea, we prescribe eye drops for patients who have had corneal transplants. After the new cornea has healed properly, we will remove the fine sutures or stitches that was placed during the surgery. This type of transplant has the potential to provide the clearest vision after healing because there is no interface (or additional layer) to look through. However, the healing time is longer, the risk of rejection exists and the use of a contact lens might be required for the clearest vision.
Descemet’s Membrane Endothelial Keratoplasty (DMEK)
Descemet’s Membrane Endothelial Keratoplasty (DMEK) is a type of corneal transplant which is a partial-thickness cornea transplant procedure that involves selective removal of the inner most layer of the cornea or Descemet’s Membrane and Endothelium. This type of Corneal Transplant is performed through a small incision, to remove and replace the inner cell layer of the cornea when it stops working properly. With this technique, we gently “strips” off the single diseased cell layer, called the Endothelium, and leaves the remaining cornea intact. This is followed by transplantation of donor corneal endothelium and Descemet’s Membrane without additional stromal tissue from a donor cornea. An air/gas bubble is placed in the eye to keep the donor cornea in position without the use of sutures. DMEK may be used for corneal diseases such as Fuchs Endothelial Dystrophy and Bullous Keratopathy. DMEK is the preferred endothelial transplant procedure due to its advantages of faster visual recovery, less rejection rate, minimal changes to your glasses prescription, and less downtime.
Descemet’s Stripping Endothelial Keratoplasty (DSEK)
Descemet’s stripping endothelial keratoplasty (DSEK) is another type of partial-thickness cornea transplant that also replaces the inner layers of the cornea. This also involves removal of the inner most layer of the cornea but is followed transplanting a thicker inner layer donor cornea tissue. Air bubble is used to keep the donor cornea in position without the use of sutures. Descemet’s stripping endothelial keratoplasty (DSEK) is an excellent option for patients whose eyes are not eligible for the DMEK procedure.
Deep Anterior Lamellar Keratoplasty (DALK)
Deep Anterior Lamellar Keratoplasty (DALK) is a partial-thickness cornea transplant procedure that can be used when the outermost layers of the cornea are diseased or damaged.
More common uses of DALK include Keratoconus and Corneal Scars. In a DALK procedure, the Endothelium, or inner layer of the cornea is left intact and all other layers of the cornea are removed. Clear healthy donor tissue is prepared from a donor cornea and sutured in place over the recipient’s own endothelium. DALK offers the benefits of fewer postoperative complications, less risk of graft and tissue rejection and a shorter need for topical anti-inflammatory medications such as steroids.
Corneal Transplants have become somewhat common in the United States as a treatment for damaged and cloudy corneas. Each year more than 40,000 people undergo corneal transplantation to restore their vision. If we find that other methods of treating your corneal disease or corneal condition are inadequate to give you good sight, we will fully discuss the risks and benefits of corneal transplantation and take the time necessary to answer all of your questions.