EyeWorld India March 2013 Issue

40 EWAP REFRACTIVE March 2013 Strengthening corneas in Singapore by Matt Young EyeWorld Contributing Writer Surgeon explains why and how he performs crosslinking during many LASIK procedures W hile there are known risk factors for ectasia after LASIK, analysis of such factors continues to remain controversial. Scoring systems can lead to incorrect predictions of risk factors that—let’s face it—still aren’t entirely understood. Even as surgeons attempt to screen out bad LASIK candidates from good ones, corneal crosslinking is—in some countries—allowing surgeons to stabilize many more corneas during the LASIK procedure. At least that’s what Jerry Tan, FRCS , believes. Dr. Tan, consultant eye surgeon, Jerry Tan Eye Surgery, Singapore, has been performing follow-up for patients who have undergone corneal crosslinking during LASIK for the last nine months. He is among a select group of surgeons performing this procedure outside of the U.S., where the procedure has yet to gain approval from the FDA. Dr. Tan performs Lasik Xtra (Avedro, Waltham, Mass., USA), which involves corneal crosslinking, on corneas potentially at risk for ectasia, on hyperopic LASIK patients as well as on very high myopes. “At present, there is no major complication we see,” Dr. Tan said. Dr. Tan explained step by step how the procedure compares to a normal LASIK procedure and his reasons for taking such steps toward more stable corneas and ones that do not regress visually. Risks vs. benefits Despite practicing Lasik Xtra over the course of the past year, Dr. Tan readily admits that the body of scientific literature supporting the procedure could be stronger. “At the present moment, there are few papers that have been written on Lasik Xtra regarding hyperopia,” Dr. Tan said. Several peer-review articles have favorably discussed Lasik Xtra for high myopia, many just appearing in the later half of 2012. Meanwhile, discussion of Lasik Xtra for hyperopia appears more prevalently not in peer-reviewed literature, but at ophthalmic meetings and in trade articles. That said, in Dr. Tan’s hands, the procedure seems to be working well for hyperopic patients. “Nobody knows why hyperopic LASIK seems to be more stable [with Lasik Xtra],” Dr. Tan said. “The cornea profile seems to be better.” For its part, Avedro says that Lasik Xtra preserves “corneal biomechanical integrity” in company literature. Essentially, a riboflavin formula is applied to the cornea during LASIK along with UVA illumination in order to bring about crosslinking with the intention of strengthening the cornea. Using topography, Dr. Tan said these hyperopic corneas post-surgery with Lasik Xtra look better—i.e., “shapes are beautiful”—compared to non-Lasik Xtra procedures. He also feels there is less regression occurring among Lasik Xtra cases—a notorious occurrence among standard hyperopic LASIK cases. High myopes also tend to experience significant regression after LASIK, but not with Lasik Xtra, Dr. Tan said. Performing Lasik Xtra Source: Jerry Tan, FRCS Jerry Tan, FRCS continued on page 43