JAN 2016

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

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Page 36 of 78

EW FEATURE 34 by Lauren Lipuma EyeWorld Contributing Writer AT A GLANCE • Topography-guided LASIK is approved for treating routine myopia with or without astigmatism. • Experts recommend starting out with normal eyes with fairly regular topography. • Operating on irregular corneas requires compensating for the refractive shift induced by neutralizing the corneal aberrations. Management of the irregular cornea • January 2016 more normal corneal shape," he said. A. John Kanellopoulos, MD, medical director, LaserVision Eye Institute, Athens, Greece, and clin- ical professor, New York University Medical School, New York, has been using this technology in Europe over the last 14 years, has published dozens of peer reviewed articles on topography-guided ablations, and proctored the first group of physi- cians performing the procedure in the U.S. Dr. Kanellopoulos pointed out that topo-guided treatments center treatment on the corneal apex, rather than the center of the pupil, and this could be one reason the procedure has had such good outcomes, which were confirmed in the recent large multicenter FDA study of topo-guided treatments. "The outcomes [of the clinical trial] were, in my opinion, astound- ing, showing that topography-guid- ed procedures had a much larger percentage of eyes gaining a line of vision—some gaining 2 lines of vision. I welcome the availability of this very effective technology for my patients in the U.S.," Dr. Kanellopoulos said. "I think this corresponds with several European investigators, including myself, who for many years have advocated for topography-guided treatments being superior to standard treat- ments, purely based on the fact that even 'normal' corneas are not perfectly symmetric, and some are not perfectly symmetric especially with regard to the corneal apex." The FDA clinical trial com- pared outcomes of standard wavefront-guided procedures to topography-guided procedures in non-aberrated corneas. In that study, nearly 65% of eyes treated with to- po-guided LASIK experienced 20/16 or better vision, according to a press release from Alcon. "I think the benefits, if you look at the clinical trial data, are some of the best results I've ever seen on virgin eyes," Dr. Solomon said. What to know before getting started Alcon's Contoura system uses either the WaveLight Allegretto Wave Eye-Q Excimer Laser System or the WaveLight EX-500 Excimer Laser System together with the WaveLight Topolyzer VARIO Diagnostic System. In conjunction with an education partner, Alcon will provide a 4-hour training program required for sur- geons who want to get started with this platform. Following the train- ing, all participants will be qualified by Alcon clinical applications spe- cialists to perform the procedure. The Contoura system is current- ly indicated and approved only for myopic patients with or without astigmatism who have not had previous corneal surgery. Dr. Solomon recommends starting off with patients who have virgin eyes and normal corneal topography. "If someone is looking to do topography-guided LASIK, I would recommend that they start out with normal corneas—virgin eyes—and get used to the process of how to take a topo-guided measurement," Dr. Solomon said. "As with most things in medicine, there's a lot of art to this science. There are nuanc- es for the staff to learn how to take good measurements and for sur- geons to understand when they are getting repeatable measurements," he said. "I think topography-guided LASIK has a lot of potential for the right patients, provided we know when to accept good data, and when we have good surgical planning," he continued. "It's not cookie-cutter at all. It's a process. But provided we get all those things in order, patients are going to do very well." David Lin, MD, FRCSC, medi- cal director, Pacific Laser Eye Centre, and clinical associate professor, Uni- versity of British Columbia, Vancou - ver, has been performing topo-guid- ed ablations since 2001. He advises that when starting out, surgeons be very selective in choosing which patients to operate on. He said that topography-guided ablations make up only 2.3% of all the LASIK cases he performs. "It's a tiny amount because the regular wavefront-opti- mized LASIK results we found were Getting started with topography-guided ablations As topography-guided LASIK enters the U.S. market, experienced surgeons share valuable knowledge they've gained about the technology A fter more than 15 years in international markets, topography-guided abla- tions are finally available to U.S. surgeons. Alcon (Fort Worth, Texas) is launching Contoura Vision, the first personal- ized topography-guided LASIK plat- form approved by the U.S. Food and Drug Administration. But this is not a simple plug-and-play technology. According to experts, refractive sur- geons must be dedicated to spend- ing the time to learn the nuances, capabilities, and limitations of this system in order to offer patients the best visual outcomes. Alcon began training a small subset of physicians on the topog- raphy-guided platform in December 2014. One of those physicians was Kerry Solomon, MD, Carolina Eye- care Physicians, Mt. Pleasant, S.C. "The whole concept of topo- guided ablations makes sense to me," Dr. Solomon said. Although wavefront-guided treatments have been the gold standard and give patients excellent visual results, Dr. Solomon thinks that topo-guided treatments are better suited for patients who will eventually need cataract surgery or other procedures to treat their aging eyes. "A topo-guided treatment also treats higher order aberrations, but it normalizes the corneal surface, so if the prescription of the eye were to change over time, now we're dealing with a more normal cornea and a Corneal topography and ablation profile for a patient undergoing topography-guided PRK, showing the areas of myopic and hyperopic ablations Source: Raymond Stein, MD, FRCSC Preop Ablation profile Myopic ablation Hyperopic ablation

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