EyeWorld India June 2020 Issue

32 EWAP JUNE 2020 REFRACTIVE A combined treatment approach using corneal crosslinking, intracorneal ring segments, and phototherapeutic keratectomy could offer keratoconus patients something once thought to be an impossibility—corneal stability and improved visual acuity. Research showed that a combined approach resulted in 13.5% of eyes achieving at least 20/25 uncorrected acuity and 96% achieving 20/40 or better best spectacle-corrected acuity, reported Guillermo Rocha, MD. 1 Evolving technique Dr. Rocha had been using all three methods independently in his practice. “In 1999, I started using Intacs [Addition Technology] for myopia, just for very low corrections,” he said, adding that it was not until around 2006, after reading reports by Joseph Colin, MD, that he began using intracorneal ring segments to tackle irregular astigmatism. Around 2010, he began using crosslinking to halt keratoconus progression. œÜiÛiÀ]…i Ü>à ˜œÌ Ã>̈Ãwi` with this alone. “I thought, ‘Some patients have low correction. What if I added a correction with the laser, then did crosslinking?’” Dr. Rocha said, adding that it occurred to him that the patient “ˆ}…Ì Li˜iwÌ vÀœ“ ˆ˜ÌÀ>VœÀ˜i> ring segments at the same time. This was also based on the pioneering work of other colleagues. Dr. Rocha’s idea of treating keratoconus with the laser continued to evolve. Already using the femtosecond laser to make channels for the intracorneal ring segments, it occurred to Dr. Rocha to shave off a little bit of the cone with the excimer laser. Dr. Rocha explained that since the epithelium in a keratoconic eye is thinnest at the apex of the cone, the rest of the epithelium could be used as a masking agent. Combining these techniques, Dr. Rocha said physicians began to see not only halting of keratoconus progression but also È}˜ˆwV>˜Ì ۈȜ˜ ˆ“«ÀœÛi“i˜Ì° “Many patients were not even wanting contact lenses and were wearing glasses in a minimal way,” Dr. Rocha said. Studying combined results A retrospective chart review was used to evaluate this combined procedure. The review included keratoconus patients with a Combined approach for managing keratoconus Contact information Rocha: rochag@me.com by Maxine Lipner EyeWorld Senior Contributing Writer This article originally appeared in the March 2020 issue of EyeWorld . It has DGGP UNKIJVN[ OQFKƂGF CPF CRRGCTU here with permission from the ASCRS Ophthalmic Services Corp. central corneal thickness of at i>ÃÌ {{ä ù“ >˜` > ŽiÀ>̜“iÌÀÞ reading of less than 55 D, Dr. Rocha said. “We found an improvement in the uncorrected visual acuity from 0.85 to 0.46 logMAR,” Dr. Rocha said, adding that corrected distance visual acuity improved from 0.19 to 0.11. The sphere in the manifest refraction improved from –4.42 to –2.94 D, and there was a reduction in cylinder of approximately 2.12 D. Those attaining uncorrected vision of at least 20/25 increased from 1.9% to 13.5%, and those who achieved 20/30 acuity went from 1.9% to 30.8%, he reported. Investigators also saw a reduction in higher order aberrations. “Total higher order aberrations, coma, spherical aberration, and secondary astigmatism all ŜÜi` ÃÌ>̈Ã̈V>Þ È}˜ˆwV>˜Ì improvement,” Dr. Rocha said. “The only one that did not improve was trefoil.” Dr. Rocha views this as a potential turning point for Preoperative topography of a 20-year-old patient with keratoconus. For patients with keratoconus, a combined treatment approach can make it possible to not only stabilize vision but improve it. Source: Judy Ku, MD, and David Rootman, MD