EyeWorld India March 2017 Issue

EWAP refractive 49 March 2017 outliers exist that may necessitate retreatment. This reality needs to be communicated to patients to adjust their expectations, or they will be unsatisfied. Not enough facts on new procedures New procedures in refractive surgery require evaluation. According to Prof. Kohnen, “When new techniques reach the market, they need to be tested. We try to do this in Germany in the KRC, to determine how safe and effective new procedures really are. We look at safe inclusion criteria, need for retreatment, and complications.” One of the more recent arrivals among refractive surgical techniques, ReLEx SMILE (Carl Zeiss Meditec, Jena, Germany), which treats nearsightedness intrastromally and involves lenticular removal, has been put on the same level as LASIK and PRK by the KRC, due to its outcomes. The procedure is best when performed for myopic corrections from –3 D to –8 D and astigmatism corrections of up to 5 D, Prof. Kohnen said. But this does not preclude complications following this procedure, in some cases. According to a Danish cohort study that implemented SMILE in 922 healthy patients (1,800 eyes) with myopia or myopic astigmatism between January 2011 and March 2013, 86% (1,346 eyes) had unchanged or improved CDVA, and a loss of two or more lines was observed in 1.5% of eyes. 4 Complications from this study included retreatments in 13 eyes, 8% haze, epithelial dryness on the first postop day in 5%, and others. “You can see that the results were not as good as what has been been achieved in modern femtosecond laser surgery, plus there were some complications, among which one in particular needs to be discussed in reference to this procedure: a small, decentered optical zone. This will not always present itself until after the surgery, when complications persist, and at which time it is too late to perform an intrastromal retreatment. We have had young patients who fit all the criteria for this procedure and due to small, decentered optical zones, were unsatisfied with their outcome,” he said. Assessing the situation too quickly Refractive surgeons need to think on their feet, as there is no blueprint to how surgeries might turn out. Careful evaluation of any given operative situation will be the key to resolving unexpected turns in the surgical scenario. Prof. Kohnen discussed a case in point of a 68-year-old female patient with cataract and astigmatism who decided on a multifocal lens implantation. Her topography was inconspicuous, and first eye cataract surgery using femtosecond laser and trifocal IOL implantation went well. After a few days, the second eye surgery followed and was set back by a posterior capsule rupture, which made implantation of the trifocal in this eye impossible. After discussing options with the patient, Prof. Kohnen decided on a three-piece bifocal IOL. The post-surgical period was difficult necessitating optic capture, but eventually the situation was rectified and the correction completed in a satisfactory manner for the patient. Prof. Kohnen said, “Assessing the operative situation and resolving problems is key. Preoperative, intraoperative, and postoperative measures always need to be taken into account. We need to make the right choices and provide excellent postoperative care to ensure successful surgical results. Early recognition of keratoconus is very important, especially for future planning in young patients and for ruling out keratorefractive surgery in the future. Also, dry eye is a problem in refractive corneal surgery that we need to address. Managing complicated situations is essential and very important to realize in refractive surgery.” EWAP References 1. Kohnen T, et al. Bewertung und Qualitätssicherung refraktiv-chirurgischer Eingriffe durch die Deutsche Ophthalmologische Gesellschaft und den Berufsverband der Augenärzte Deutschlands. Updated January 2014. Ophthalmologe . 2014;111:320–329. 2. Bühren J, et al. Wellenfrontaberrationen und subjektive optische Qualität nach wellenfront-geführter-LASIK: Erste Ergebnisse. Ophthalmologe . 2007;104:688–696. 3. Kohnen T, et al. Correction of moderate to high myopia with a foldable, angle- supported phakic intraocular lens: results from a 5-year open-label trial. Ophthalmology . 2016;123:1027–35. 4. Ivarsen A, et al. Safety and complications of more than 1500 small- incision lenticule extraction procedures. Ophthalmology . 2014;121:822–28. Editors’ note: Prof. Kohnen has no financial interest related to his comments. Contact information Kohnen : kohnen@em.uni-frankfurt.de Index to Advertisers Alcon Page: 32, 33 www.alcon.com Feather Safety Razor Page: 35 www.feather.co.jp Haag-Streit AG Page: 17 www.haag-streit.com OCULUS Optikgeräte Page: 59 www.oculus.de Ziemer Page 64 www.ziemergroup.com ASCRS Page 2, 13, 25, 43, 46 , 50 www.ascrs.org APACRS Pag e 5, 7, 8, 9, 30 , 31 , 55 , 56 , 62 , 63 www.apacrs.org ESCRS Page 19 www.escrs.org EyeWorld Page 36 , 38 , 41 www.eyeworld.org