EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/220233
February 2011 November 2013 Corneal crosslinking Contraindications In the learning process of discovering the best selection methods for crosslinking in keratoconus patients, contraindications were found. For instance, patients with neurodermatitis are contraindicated for crosslinking, Dr. Seiler said. These cases can develop an ulcer after the epithelium is removed as epithelialization is slow or does not happen, he said. An additional contraindication for crosslinking includes severe dry eye, as a very poor tear film can be a risk factor for a significant delay in epithelial healing, Dr. Trattler said. Contraindications for epi-on can be different than epi-off procedures because the epithelium is not removed, Dr. Cummings said. He is taking part in a study of epi-on crosslinking in Ireland. "If we can, in the future, do epithelium-on crosslinking, then … the contraindications change completely," Dr. Cummings said. "The biggest risk to the procedure is when you remove the epithelium. You remove the barrier to infection and the biggest problem we've seen so far with crosslinking is delayed epithelium healing. If you're not removing the epithelium, you've removed that potential problem." Prepping patients Crosslinking with UV-X 1000 device Source: Arthur B. Cummings, MB ChB Loading the cornea with riboflavin using a corneal sponge during epi-on CXL Source: William B. Trattler, MD Preparing keratoconus candidates for crosslinking can be as important as selection, physicians say. Visual improvement with the epi-off procedure does not usually occur for three months after the procedure, and there is the potential for decreased vision for up to one month. The typical patient experiences a continued beneficial visual and topographical impact of crosslinking for up to three years following the procedure, Dr. Stulting said. Patients need to be educated about these timelines, he said. Crosslinking is painful, too, Dr. Seiler said. He likened the pain to "snow blindness" or a scratch on the cornea. He said patients should be told in advance that the procedure will hurt. Also, patients should be told that they cannot wear their contact lenses and will be photophobic for at least one month following the epi-off procedure. The photophobia is related to stromal EW FEATURE 39 haze that happens after crosslinking, which typically takes about six months to clear, he said. In contrast, Dr. Trattler noted that patients can often return to contact lenses within a few days after epi-on crosslinking. Because of the time involved in visual improvements occurring and the potential for improvements not occuring, Dr. Cummings said that he is upfront with patients about what they can expect from crosslinking. Many of his cases are crosslinking combined with another procedure, so all patients first watch a 20minute video about crosslinking and combined options. After the consent form is signed, he sits down and asks patients "Why are we doing this procedure?" "Patients will say to me, 'We're doing this procedure to stop the keratoconus from getting worse." And that's the key indication. If someone misunderstood me and said, 'I think this is going to improve my vision,' I say, 'If we're only doing crosslinking, I'm only trying to stop [keratoconus from] getting worse. We're not doing anything to improve the visual outcome,'" he said. EW Editors' note: Drs. Cummings, Seiler, and Stulting have no financial interests related to this article. Dr. Trattler has financial interests with CXLO. Contact information Cummings: abc@wellingtoneyeclinic.com Seiler: info@iroc.ch Stulting: dstulting@woolfsoneye.com Trattler: wtrattler@gmail.com