Eyeworld

101 the other in the individual case," he said. Dr. Kanellopoulos said he thinks PiXL could be combined with topog- raphy-guided PRK as well for even better refractive outcomes. "In my mind, any patient with a refractive error resulting from corneal ectasia and keratoconus is a good candidate for the Athens protocol [topography-guided PRK followed by crosslinking]; having PiXL in our hands, we can employ [it] in combination with the partial topography-guided PRK in order to achieve a better refractive correction of the cornea and also being able to remove less tissue and/or being able to apply this even in corneas where no tissue can be removed due to lim- itations from cornea thinning that go along with ectasia," he said. Where to go from here Dr. Kanellopoulos said PiXL is his treatment of choice for patients with corneas too thin to consider an exci- mer or femtosecond laser procedure and for post-cataract surgery pa- tients left with only a small amount of ametropia. Still, he said more needs to be learned about cornea biomechanics and variability among patients. He also said a dose effect nomogram needs to be developed. Dr. Pinelli thinks PiXL should be improved when it comes to the time and energy currently required in the procedure. "Sometimes the treatment is too long; we should stay within the accelerated crosslinking parameters," he said. Dr. Behndig said more research is needed to optimize treatment parameters of PiXL for both kerato- conus and myopia patients. EW Editors' note: Drs. Behndig and Pinelli have no financial interests related to their comments. Dr. Kanellopoulos has financial interests with Alcon (Fort Worth, Texas), Allergan (Dublin), A.R.C. Laser (Nuremberg, Germany), Avedro, KeraMed (Orange, California), Optovue (Fremont, California), and Carl Zeiss Meditec (Jena, Germany). Contact information Behndig: anders.behndig@umu.se Kanellopoulos: ajkmd@mac.com Pinelli: pinelli@seri-lugano.ch September 2016 EW REFRACTIVE A 45-year-old male with 2 D myopia received epi-on PiXL treatment. His preop measurements are on the left, postop in the middle, and the difference between the two on the right. These are the difference maps (preop top right, postop bottom right, and preop minus postop left) documenting excimer-like correction with crosslinking alone in a pseudophakic female who achieved 2.5 D of myopic correction with PiXL treatment. Source: A. John Kanellopoulos, MD

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