When a patient is faced with impaired vision or eye pain due to Fuchs’ dystrophy, it can be difficult to know which procedure – DMEK or DSAEK – is the most appropriate to treat the disease. In some eye hospitals or ophthalmic centers, this is a controversial topic due to differences in surgeon experience. However, each procedure has its own advantages, that – when compared – can make the choice clear.
But first – what are DMEK and DSAEK? Both are procedures to restore vision in an eye with Fuchs’ dystrophy. DMEK, or Descemet’s Membrane Endothelial Keratoplasty, is a procedure in which defective pump (endothelial) cells in the cornea are replaced strictly with healthy pump cells from a donor cornea. DSAEK, or Descemet’s Stripping Automated Endothelial Keratoplasty, is a procedure in which a piece of donor cornea containing healthy pump cells is used to replace the defective pump cells.
Advantages of DMEK over DSAEK
- DMEK provides better vision. Large series demonstrate that visual acuity after DMEK can be 20/25 or better 75 percent of the time, while visual acuity after DSAEK will be limited to 20/30 or worse 75 percent of the time.
- DMEK not only provides better vision, but better vision faster, with best vision returning sooner than with DSAEK.
- DMEK transplants have a 15 times lower risk of rejection than do DSAEK transplants.
- Steroid drops, with their attendant difficulties, are not needed for as long a time period or in as high a potency after DMEK as they are after DSAEK.
- A transplant with the same number of endothelial cells done with DSAEK will be about 5 times larger than a comparable transplant done with DMEK. The DSAEK operation requires a larger incision in order to insert the larger piece of tissue. The extra DSAEK tissue is actually counterproductive, since it causes poorer visual outcomes and an increased risk of rejection.
Advantages of DSAEK over DMEK
- More surgeon choice is available to DSAEK patients. Even now, in late July 2015, relatively few corneal surgeons have significant experience with DMEK surgery. DSAEK is an older procedure that is now widely available.
- Very cloudy corneas may be able to benefit from DSAEK, but a relatively clear cornea is needed for DMEK surgery. Because DMEK transplants are so small, they can be difficult to see inside an eye with a cloudy cornea. DSAEK transplants, which are 5 times larger than the comparable DMEK transplant, are more easily seen (and transplanted) in eyes with very cloudy corneas.
If you’re struggling with your treatment options for Fuchs’ dystrophy, call Parker Cornea for a consultation. Dr. John Parker was one of the first ophthalmologists in the U.S., and the first in the region, to perform both DSAEK and DMEK surgery. Dr. Parker has offered DSAEK since 2004 and DMEK since 2011, and has performed both procedures hundreds of times.