For more than 100 years, full-thickness corneal transplant had been the most commonly performed surgical procedure for addressing the cloudiness and edema caused by corneal diseases and conditions. In just the past 10 years, less invasive transplant methods have been developed and refined, making endothelial keratoplasty the current procedure of choice for treating patients who have a poorly functioning corneal endothelium such as occurs with Fuchs’ dystrophy or other disorders and damage. Barnet Dulaney Perkins Eye Center corneal specialist Dr. Robert Fintelmann performs two types of endothelial keratoplasty.
In DSAEK (Descemet’s stripping automated endothelial keratoplasty), the patient’s Descemet’s membrane and endothelial cell layer are removed and replaced with donor tissue that rests on 100-150 µm of donor stroma. DSAEK requires significantly less surgical time and recovery time than a full-thickness transplant. While recovery from a full-thickness transplant can take more than a year, patients can expect most of their visual recovery to occur in 3-4 months after DSAEK, and further improvement may continue for several years.
Dr. Fintelmann recently became the first surgeon in the Phoenix area to perform DMEK (Descemet’s membrane endothelial keratoplasty), the newest type of endothelial keratoplasty. In DMEK, the patient’s Descemet’s membrane and endothelium are replaced with donor tissue, but no donor stroma is added to the eye. The replaced tissue measures only 10-15 µm, about one-tenth the thickness of a human hair. The incisions needed to insert this amount of tissue are smaller than those required for DSAEK and much less invasive than a full-thickness transplant. DMEK may require more surgical time than DSAEK, but a higher percentage of patients achieve 20/20 vision with DMEK than with DSAEK (up to 80% vs. up to 50%), provided they have no other conditions affecting their vision. Also, this level of vision can be achieved more quickly than with DSAEK. Most of the visual recovery following DMEK occurs in a few weeks. In addition, the rate of graft rejection appears to be lower with DMEK than with DSAEK (3% with DMEK vs. up to 14% with DSAEK).
In both DSAEK and DMEK, gas or air is used to initially place the donor tissue and keep it in position. If the tissue does not attach properly within weeks, an additional injection of gas or air may be needed. This seems to be necessary more often with DMEK. Either surgery can be repeated if necessary, and if one does not provide the desired results, the other can be performed in an effort to attain better vision.
Dr. Fintelmann is available in our Phoenix, Sun City and Mesa locations for corneal surgery consultations with patients.