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3 World Cornea Congress VII, San Diego 2015 EW SHOW DAILY The "big insight," Dr. Price said, came in 1998, when Gerrit Melles, MD, PhD, Rotterdam, injected air under the donor. Dr. Melles found there was no need for sutures: By stripping the Descemet's membrane, the donor would simply stick to the posterior surface of the cornea. The procedure, Dr. Price said, "really took off from there." In these early versions of EK, however, the donor tissue was dis- sected manually, resulting in uneven grafts and equally uneven results. Mark Gorovoy, MD, Fort Myers, Fla., then had the idea of using the microkeratome instead of hand dis- section to create the donor graft— hence, the next iteration, Descemet's stripping automated endothelial keratoplasty (DSAEK). Following the procedure's evolution toward lamellar specificity has logically brought about its latest iteration—Descemet's membrane endothelial keratoplasty (DMEK). Due to the thinness of the graft, it is commonly thought by surgeons that the limiting step of this procedure is donor preparation. Dr. Price called this a myth, saying that surgeon-prepared tissue resulted in less than 1% donor loss. The true limiting step, he said, is manipulating and positioning the graft intraoperatively—which, he pointed out, is the fun of being a cornea surgeon. Looking toward the future, Dr. Price cited Shigeru Kinoshita, MD, in Japan, who is working on cell cultures that may be injected or implanted through grafts, or using agents such as Rho-kinase inhibitor, either injected or administered as topical drops, to stimulate regrowth of the endothelium. In terms of what cornea sur- geons have learned over the years throughout the evolution of EK, Dr. Price said that 7 "givens" cornea experts believed in 2005 have been overturned: today, we know that guttae decrease vision, even with- out edema; doing phaco alone does not "do your Fuchs' patients a favor"; there is no need to wait a year between grafting each eye; older donors are better than younger donors for DMEK; stromal tissue is important for immune recognition (and so effect rejection); great vision for eyes can be achieved even with glaucoma; and tubes are worse than trabeculectomy for the cornea, with poorer survival rates and more intense changes in anterior chamber fluid proteins. In light of these facts, and the fact that more and more tubes are being implanted at present, Dr. Price said the challenge for cornea experts at WCC in 2025 will be that the most common cause of corneal decompensation will be tubes: There will thus be "a lot of repeat grafts," Endothelial keratoplasty continued from page 1 'Techniques and Technologies for Endothelial Keratoplasty' I n addition to Dr. Price's keynote address, "The Evolution of Endothelial Keratoplasty: Where Are We Headed?" these physicians spoke on the following topics: • Jesper Hjortdal, MD, PhD, Aarhus, Denmark, spoke on "Optics of Posterior Lamellar Grafts." • Sanjay V. Patel, MD, Milford, Conn., spoke on "Effect of Graft Thickness on Visual Outcomes in DSEK Surgery." • Kenneth M. Goins, MD, Iowa City, Iowa, spoke on "Descemet's Stripping Endothelial Keratoplasty Surgery in Complex Eyes." • Frederich E. Kruse, MD, Erlangen, Germany, spoke on "Graft and Recipient Preparation Techniques in DMEK Surgery." • Nicolas Cesário Pereira, MD, São Paulo, Brazil, spoke on "Descemet's Membrane Endothelial Keratoplasty: Surgical Strategies to Reduce Complication Rates." • Amar Agarwal, MS, FRCS, FRCOphth, Chennai, India, spoke on "Role and Rationale for Pre-Descemet's Endothelial Keratoplasty." • Gerrit R.J. Melles, MD, PhD, Amsterdam, the Netherlands, spoke on "Descemet's Membrane Endothelial Transfer Surgery: Is This the Next Step?" EW the phenotype of the disease and their definitions often change when new research is published. "To use a terminology that can change with one investigation sug- gests that our clinical phenotyping on its own, without imaging, is not robust," he said. Complicating the problem is the fact that corneal opacities are often treated with penetrating keratoplas- ty even when the disease doesn't originate in the cornea itself. Often these patients have a poor prognosis and their grafts frequently fail. "If you have congenital glauco- ma and a corneal opacity, if I said to you that the way to treat that was to do a corneal graft, you would think I was mad, and you would be right," Dr. Nischal said. "But equally, there are conditions inside the eye affecting the lens that give you a corneal opacity, and we do a corneal transplant and expect it to work. That is equally mad." A novel classification system A better way to describe congenital corneal opacities is to classify them as primary and secondary corneal diseases, Dr. Nischal said. Prima- ry corneal diseases are defined as developmental anomalies of the cornea only, and secondary corneal diseases are anomalies that originate in another part of the eye but have corneal symptoms. In these cases, the corneal opacity is a sign, rather than a disease in itself. Secondary corneal diseases are often not well understood genotyp- ically, he said, and are frequently lumped under the categories of "Peter's anomaly" or "sclerocor- nea." These terms are unhelpful for diagnosis, he added, because they don't translate or communicate a sign or a disease. In order to make progress, physicians need to make distinct diagnoses of these diseases, he said, rather than grouping them together under headings that don't make sense. One of the most remarkable examples of inaccurate classification with the old system is microphthal- mia dermal aplasia sclerocornea, or MIDAS syndrome, Dr. Nischal said. MIDAS is not a primary corneal disease but a systemic disease that causes a secondary keloid-like reac- tion in the cornea. "This is not a primary corneal disease, so it doesn't make any sense to me to call it sclerocornea, because the problem is not the sclera or the cornea," he said. "To label this as sclerocornea or Peter's anomaly doesn't impart the gravity of the intraocular complications you're about to deal with." Determining the best treatment options After describing the new classifica- tion system, Dr. Nischal presented the algorithm he and his colleagues use to determine the best course of treatment for children who present with congenital corneal opacities, rather than going straight to a corneal transplant. "No surgery, no intervention sometimes is a very good choice, depending on the systemic status and the social status of the child," he said. While graft clarity after kera- toplasty has been considered the gold standard for measuring success in the past, it does not necessarily translate to sufficient vision needed for development, Dr. Nischal said, so physicians should shift their focus to measuring success by achieving visual results that allow the child to develop globally as well as visually. "A small improvement in vision in the first year of life has a dramatic effect on global development," he said. "Graft clarity no longer can be what we measure success by in infant keratoplasty." EW Editors' note: Dr. Nischal has no finan- cial interests related to this article. and surgeons need to learn how to handle those cases. Dr. Price's "dream" is for more DMEK to be performed all over the world to address endothelial failure. In any case, he said, "EK is amazing." EW Editors' note: Dr. Price has financial interests with Bausch + Lomb (Bridgewater, N.J.). A novel continued from page 1

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