EyeWorld India March 2019 Issue

47 March 2019 EWAP REFRACTIVE Getting better reading vision with EDOF lenses by Liz Hillman EyeWorld Senior Staff Writer Ophthalmologists describe nanovision and recent studies that showed a good range of vision at all distances, including improved reading vision M onovision—induced via contact lenses, as a laser refractive surgery, or as a pseudophakic lens-based procedure at the time of cataract surgery—is a well-known method of increasing reading vision in the nondominant eye of presbyopes while maintaining good distance vision in the dominant eye. Nanovision, on the other hand, is a relative newcomer to the conversation of surgical presbyopia correction. Three paper presentations, 1,2,3 at the 2018 ASCRS•ASOA Annual Meeting, which have been submitted to peer-reviewed journals, describe the technique, which was found to provide good vision at near, intermediate, and distance and resulted in high patient satisfaction. Nanovision, as explained by Eric Donnenfeld, MD, Ophthalmic Consultants of Long Island, Rockville Centre, New York, who was involved in the research, capitalizes on the good distance vision of low add multifocal or extended depth of focus (EDOF) lenses. The nondominant eye is left about 0.5 D myopic to induce a “nano” version of monovision to improve reading vision further. “The concept of nanovision is to add reading vision without sacrificing binocular distance vision, and I think it speaks to the lack of technology to meet the needs of patients in the United States who want to have spectacle independence and also maintain their distance,” Dr. Donnenfeld said. “This is just one way of achieving that type of spectacle independence. You could go to a higher add multifocal, but you get the drawback of increased halo and glare at distance. We don’t have trifocals available in the United States, but they have become successful in Europe, and they solve this problem.” Dr. Donnenfeld called nanovision a “temporary solution that gives patients good visual quality with little sacrifice.” Just how much sacrifice is that? That’s what Dr. Donnenfeld and others sought to establish in an investigator-initiated trial regarding nanovision and its use with the Tecnis Symfony (Johnson & Johnson Vision, Santa Ana, California) EDOF lens. The research, a prospective, multicenter, randomized study, investigated visual acuity outcomes of eyes with the Symfony toric IOL targeted for emmetropia or nanovision. Researchers also evaluated defocus curve and reading speed results in patients with Symfony toric lenses targeted for emmetropia in both eyes or nanovision. The research enrolled 120 patients with regular astigmatism who had the potential of achieving 20/30 or better and 0.5 D residual astigmatism or less postoperatively. Visual acuity was assessed at 1 and 3 months postop at 4 m, 66 cm, and 40 cm at uncorrected and best distance corrected. While there was no significant difference in binocular UCVA between the two groups at distance and intermediate, uncorrected near visual acuity was significantly better in the nanovision group by half a line on average. Reading speed was also assessed and found to be slightly better in the nanovision group, though no significant difference was seen between the two groups. There was no difference in defocus curves between nanovision and emmetropia. Kerry Solomon, MD, Carolina Eyecare Physicians, Mount Pleasant, South Carolina, who was involved in the study, said the results, for the most part, were expected, but there were a couple of surprising factors. “What was a surprise is the intermediate vision was measured better in the nanovision eyes; that wasn’t expected, but it was a real finding,” Dr. Solomon said, adding later, “The even bigger surprise finding was when we gave patients a questionnaire on how they think their vision in the distance, intermediate, and near was compared to the patients with both eyes set for distance. … The patients with nanovision felt their distance vision was better compared to how the distance vision patients rated their distance vision. Even though I know the distance vision measures slightly worse in the nanovision group, they weren’t bothered by it. The take-home message for me was functional vision. If I can give someone better functional vision for intermediate, computers, and reading, they’re happy with their distance vision even if there is a little bit of a distance blur.” “I think that the take-home message is that this technique was well tolerated by patients and there was a significant improvement in reading for these patients without compromising distance,” Dr. Donnenfeld said. “It met the needs of our patients.” Drs. Donnenfeld and Solomon said nanovision has become a regular part of their conversation with patients. Dr. Donnenfeld said with older generation multifocal lenses, there was a concern about Symfony IOL placed with a refractive error of –0.50 D in the nondominant eye for nanovision. Source: Eric Donnenfeld, MD Continued on page 48