Endothelial keratoplasty has evolved greatly over the past 16 years: from the deep lamellar endothelial keratoplasty (DLEK) procedure of a hand-dissected donor placed in a hand-dissected bed to today’s most common procedure, Descemet’s stripping automated endothelial keratoplasty (DSAEK)—where a microkeratome donor is placed like a wart on the back side of the cornea—and on to Descemet’s membrane endothelial keratoplasty (DMEK), which replaces a diseased-stripped Descemet’s membrane with a healthy donor Descemet’s membrane.
Reasons for performing DMEK procedure
Mark A. Terry, MD, summarized three top reasons for why DMEK should be used for all routine cases of EK:
1. Visual results
2. Lower rejection rate
3. Less steroid-induced glaucoma
The primary reason to adopt DMEK is that it represents exact anatomic replacement, explained Dr. Terry, director of the Cornea Service, Devers Eye Institute, Oregon Health Sciences University, Portland, OR.
Vision results are better with DMEK than DSAEK, and the visual recovery is much faster. There is also a lower rejection rate using DMEK (<1%) compared with DSAEK (9%).
A version of DSAEK known as “ultra-thin” is sometimes thought to have vision results as good as using DMEK, but the literature shows about twice as many patients will have 20/20 vision using DMEK over ultra-thin DSAEK.1-3
Despite this, the popularity of DMEK in the United States has not increased greatly, Dr. Terry noted.
In 2016 in the United States only 6,459 cases were done using DMEK, out of 28,327 total EK cases. Part of the reason for this may be the perception that it is not easier, and not faster in the operating room.