Eyeworld

JULY 2023 | EYEWORLD | 49 R by Liz Hillman Editorial Co-Director About the physicians Renato Ambrosio Jr., MD, PhD Professor of Ophthalmology Federal University of the State of Rio de Janeiro and Federal University of Sao Paulo Rio de Janeiro, Brazil Y. Ralph Chu, MD Founder and Medical Director Chu Vision Institute Bloomington, Minnesota Relevant disclosures Ambrosio: Alcon, Carl Zeiss Meditec, Mediphacos, Oculus Chu: Carl Zeiss Meditec O ver the last 20 years, refractive surgery has expanded beyond the cornea and to intraocular correc- tion. There have been so many advancements on the diagnostic and procedural front that Y. Ralph Chu, MD, said refractive surgery is truly its own subspecialty. "It takes equipment commitment, mental commitment. You have to structure your prac- tice around refractive surgery. I think that over the last 10 or more years, refractive surgery has evolved to where unless you're fully committed to it, it's hard to just dabble in it," he said. "You need the right diagnostic technology. You need easy access to laser technology. There is staff education, energy, and internal expertise needed to manage the high expectations of the modern refractive surgery patient." Some of the more recent advancements have been at the diagnostic level. Specific to LASIK, Dr. Chu said one of the biggest things to happen on the preoperative screening front is epithelial thickness mapping. This, Dr. Chu said, helps surgeons identify what might be causing asymmetry on topography as it relates to the epithelial surface. "Sometimes asymmetry on the topography can be the result of epithelial basement mem- brane dystrophy. It could be the result of epithe- lial disorders that aren't structural anomalies, so patients can still have a refractive surgery. Epithelial mapping has helped surgeons screen in and screen out patients who are good or bad patients more effectively," he said. Renato Ambrosio Jr., MD, PhD, shared with EyeWorld an editorial on the concept of multi- modal refractive imaging 1 and a review paper he co-authored describing the value of epithelial thickness mapping. The authors concluded that conscious application of such measurements "significantly impacts safety and efficacy of refractive surgery, and also allows for significant improvement for therapeutic procedures." 2 Dry eye diagnostic technologies and tests have also impacted the screening of patients. "I think incorporating some type of ad- vanced diagnostic dry eye test is important, and I think for a refractive surgeon, tear breakup time and meibomian gland imaging are helpful because the quality of the tears is important for quality of vision after any refractive surgery," Dr. Chu said. If dry eye is identified and able to be addressed preoperatively, Dr. Chu said it might allow a patient to be a candidate for LASIK or another refractive procedure, like SMILE. In a presentation that Dr. Ambrosio sent to EyeWorld, he credited the range of advances in diagnostics that allow the surgeon to determine the best refractive procedure for each patient's unique situation, as well as prevent complica- tions in patients who might be at a higher risk. He also said in the presentation that it's im- portant to remember whether the procedure is refractive or therapeutic. Equipment updates advancing refractive surgery continued on page 50 Figure 1. Placido disc-based corneal topography; note the irregular tear film on Placido's reflection and irregular steepening on the axial map Figure 2. Scheimpflug tomography; irregular astigmatism has a similar pattern as in Figure 1; the thickness map indicates thickening in the steeper zone, which does not resemble an ectatic pattern Source: Renato Ambrosio Jr., MD, PhD

• Blank Page
• Blank Page (1)