EyeWorld Asia-Pacific December 2016 Issue

December 2016 more severe than with cataract surgery. The tenth question was, “Do you prefer combined cataract + DSAEK or staged surgery?” First cataract then DSAEK at a later date 61% Combined cataract + DSAEK 39% Performing cataract surgery first then DSAEK at a later date has two main advantages. First, if cataract seems to be the primary cause of vision loss, it may be worthwhile trying cataract surgery alone, which is less invasive and without risk of rejection. A second advantage is that the anterior chamber may be more stable after the lens implant is more secure, making DSAEK easier. In terms of disadvantages of staged procedures, two procedures rather than one results in added expense and inconvenience to the patient. In addition, corneal edema after cataract surgery may be worse and disadvantageous for the DSAEK surgery. EWAP Editors’ note: Dr. Gossman is in private clinical practice at Eye Surgeons & Physicians, St. Cloud, Minnesota. He has no financial interests related to this article. Contact information Gossman : n1149x@gmail.com are often able to cover the defect caused by Descemet’s stripping has to do with loss of contact inhibition. “We know that the corneal endothelium is contact inhibited, which means that when the cells reach each other they stop growing,” she said. “By physically removing the dysfunctional central endothelial cells, I release the contact inhibition, presumably allowing healthier cells to come from the periphery of the cornea.” What remains unknown, however, is whether the cells are just spreading to cover the area, or whether stem cells in the periphery are dividing and sending new cells in once the contact inhibition is released, Dr. Colby said. Investigators are uncertain why the procedure did not work for everyone. One consideration was whether there may be a different genetic profile of Fuchs’ endothelial dystrophy in responders versus non-responders. “In this small cohort, we did not see a difference,” she said. Likewise, diabetes and smoking, both of which can lead to states of increased oxidative stress, were not correlated with response. However, investigators found that those whose corneas were thicker than 625 microns preoperatively, were less likely to clear, Dr. Colby noted, adding that paradoxically the technique worked in her very first patient who had a corneal thickness of more than 650 microns. What’s more, he cleared very quickly. “The good news is if it doesn’t work, there are no technical issues with performing subsequent endothelial keratoplasty,” Dr. Colby said. “Three people in this series did require subsequent DMEK and that was not a problem.” In the clinic For patient selection, she encourages practitioners to consider those who have predominantly central guttae with a preserved endothelial mosaic in the periphery. “One needs to carefully evaluate the peripheral endothelium by slit lamp examination and endothelial imaging,” she said. “I would not do this on a patient who has guttae across the entire cornea because it’s not going to work.” Patients who are contemplating Descemet’s stripping without endothelial replacement have to understand that the procedure is a novel one that may not work for them, but if it does, it means they will not require someone else’s cells in their eyes. “If they’re not OK with that, you should go ahead and do your regular phaco DSEK or DMEK,” Dr. Colby said. But in cases where it works, patients are usually very enthusiastic. “All of my patients in whom it was successful were very pleased to avoid the need to have a foreign material in their eye and the need for chronic steroids,” she said. EWAP Reference 1. Borkar DS, et al. Treatment of Fuchs endothelial dystrophy by Descemet strip- ping without endothelial keratoplasty. Cornea . 2016;35:1267–1273. Editors’ note: Dr. Colby has no financial interests related to this article. Contact information Colby : kcolby@bsd.uchicago.edu Finessing - from page 54 Comparison - from page 55