EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/274531
E W FEATURE 60 by Erin L. Boyle EyeWorld Senior Staff Writer DMEK experts offer pearls, pitfalls for performing procedure "It has made being a corneal surgeon so much more fulfilling as we offer a truly customized ap- p roach to our patients," she said. "Our patients are benefiting from this, and I think it has enriched our experience as corneal surgeons, knowing that our surgical approach is now a far more deliberate approach than the 'one size fits all' approach we had with penetrating keratoplasty." " DMEK is part of this evolu- tion," Dr. Shamie said. "I don't think it's going to necessarily replace DSAEK. I think it's a nice addition to the armamentarium of a lamellar corneal surgeon and one that should be offered to those patients who would benefit from it." Francis W. Price, MD, Price Vision Group, Indianapolis, and chairman of the board and founder, Corneal Research Foundation of America, Indianapolis, said that re- sults show that DMEK is producing good outcomes for patients. "I think as data comes out from multiple centers, what we're seeing is that the rejection rate is much lower with DMEK than any of the other transplant procedures," said Dr. Price. "Visions are better. There's less distortions in the form of higher order aberrations, and we have a smaller incision size." Advances in instrumentation "DMEK is ready for prime time," Dr. Straiko said. The reasons that he cited are advances including avail- ability of pre-stripped tissue and the development of a glass, closed system injector, the Straiko DMEK injector, which he invented to simplify tissue delivery. The two biggest advancements in the procedure have been how the tissue is inserted into the eye, Dr. Price said, with closed systems offering the best results, and most importantly improvements in un- folding the grafts including using a slit lamp or OCT to determine the orientation of the endothelial side of the graft. "Both of those have made a huge improvement in the ability to put the donor into the eye, get it to unfold, and go into place," Dr. Price said. According to Dr. Straiko, "Our eye bank has developed a technique to apply an 'S' stamp to eliminate February 2011 Corneal infections February 2014 The lamellar transplant procedure is an effective corneal transplantation option, with new advances assisting treatment D MEK (Descemet's membrane endothelial keratoplasty) continues to provide good outcomes in corneal transplanta- tion procedures, including in Fuchs' endothelial dystrophies and pseudophakic bullous keratopathy cases, offering the possibility of 20/20 vision or better. However, concerns remain about endothelial cell survival and the learning curve, with some sur- geons still hesitant to use the proce- dure, preferring instead to perform Descemet's stripping automated endothelial keratoplasty (DSAEK). "DMEK is an exciting advance but it is still a relatively new tech- nique," said Michael Straiko, MD, Devers Eye Institute, Portland, Ore. "It has been shown to offer better vision, faster visual recovery, and lower graft rejection rates than DSAEK, but it will need to be sup- ported with long-term endothelial cell survival rates as well." The new era of lamellar corneal surgery—progressing from penetrat- ing keratoplasty to endothelial ker- atoplasty procedures such as DSAEK and DMEK, and deep anterior lamel- lar keratoplasty (DALK) to target stromal disease—has provided corneal surgeons with varied individualized approaches to treat corneal disease, said Neda Shamie, MD, associate professor of ophthal- mology, Keck School of Medicine, University of Southern California, Los Angeles. AT A GLANCE ¥ Studies have shown DMEK is a successful procedure but some c oncerns remain. ¥ One key pearl for the beginning DMEK surgeon: Use pre-stripped tissue from an eye bank. ¥ One key pitfall for the beginning DMEK surgeon: DMEK has a high rebubble rate. Donor graft is being inserted into the eye. The donor is stained with trypan blue so that it can be seen. An IOL cartridge and inserter are used that provide a closed system so the back pressure from the anterior chamber does not push the donor back into the cartridge. DMEK graft is inserted into the anterior chamber with small air bubble under it. The air bubble pushes the donor up against the recipient cornea, and the cannula is being used to unfold the donor. Anterior chamber is completely filled with air pushing the donor firmly against recipient. Source (all): Francis W. Price, MD 56-68 Feature_EW February 2014-DL2_Layout 1 1/30/14 10:44 AM Page 60