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EW REFRACTIVE SURGERY 50 August 2014 by Maxine Lipner EyeWorld Senior Contributing Writer Slowing down the myopia train Strategies for decelerating progressive nearsightedness I n some parts of the world myopia has become the norm, with a 90% prevalence level in various Asian populations, according to Thomas A. Aller, OD, senior project scientist, Vision Cooperative Research Center, Syd- ney, Australia. In the February issue of Eye, Dr. Aller offered strategies for slowing down progressive myopia. On the slow track One tactic to try to halt myopia involves topical use of atropine. The Cochrane Collaboration, from Johns Hopkins, reviewed studies consider- ing this approach, Dr. Aller reported. "Based on the studies that they looked at, their primary recommen- dation was that atropine had the most promise for controlling myo- pia," he said, adding that this has generally been given at a 1% dosage, which has many side effects. "Pupils dilate dramatically, there's no ac- commodation, there's photophobia, and children have to wear bifocals," Dr. Aller said. "It's practically a gruesome way to treat myopia." Still, with the technique, myopia progression was cut to almost zero, he said. However, use of lower doses, potentially with fewer side effects, is also possible. "They found that even 0.01% atropine has a very nice clinical effect approaching 60%," Dr. Aller said. In addition, with low dosages, the myopia rebound effect experienced when atropine use stopped is not nearly as great. "When you discontinue (traditional) atropine, all of those receptor sites may be hypersensitive, and you get a rebound where the nearsighted- ness jumps up and you lose a lot of the advantage that you had when you were on it," Dr. Aller said. "With the 0.01% or the 0.02%, that doesn't seem to happen." Orthokeratology (Ortho-K) was another strategy highlighted by the group. "This is the treatment of wearing hard or rigid gas-permeable lenses in order to reshape the eye," Dr. Aller said. As a result, the center is made flatter and the mid-periph- ery steeper, akin to laser surgery, he explained. "Ortho-K has been shown to reduce the rate of progression of my- opia by 50% in at least one random- ized controlled clinical trial, which went on for 3 years," Dr. Aller said. There is some suggestion, however, that this seems to work better on those with moderate to high levels of initial myopia, he said. With Ortho K, the signal for the eye to stop growing is generated by the power difference between the flat- tened central cornea and the steep- ened mid-peripheral area, he said. This might also work with laser treatment; however, it is only FDA approved for non-progressing myopes. "There have been studies to show that 10 years after laser there doesn't need to be a very high percentage of retreatments," he said. While this seems to suggest that laser treatment is helpful in fore- stalling myopia, the eligible patient population is, of course, those who are not progressing, he said. Use of bifocal contacts is yet another approach being tried. "Bifocal contact lenses generally have the distance vision corrected in the center surrounded by either a ring or several rings of plus power," Dr. Aller said. "In that sense, there's some similarity between the optical effect of Ortho-K, which has the central distance vision corrected through reshaping with plus in the periphery because it's uncorrected out there." A number of studies have put the success rate for use of bifocal contact lenses at about 50%. Dr. Aller has been studying use of bifocal contact lenses in those with a tendency for their eyes to over-converge while reading, known as eso fixation. "That has been shown in a number of studies to be another trigger to myopia progres- sion," Dr. Aller said. He prescribes bi- focal lenses in a way that eliminates the eso fixation disparity, thereby also doing away with one of the triggers to growth. Additionally, these lenses have added plus power in the periphery, something that has been found to slow down nearsightedness. Peripheral stop signal He cited the work Earl L. Smith, OD, PhD, Houston, conducted on monkeys. "He showed that by manipulating the focus on the back of the eye in these monkeys you could either cause their eyes to grow or to stop growing," Dr. Aller said. This flies in the face of the long-held belief that it was the fovea that was important here. "Everyone ignores the periphery, but what he found was that you could manipulate the 2014 ASCRS Clinical Survey by David F. Chang, MD, EyeWorld chief medical editor Responses of more than 1,500 physicians will guide educational content I am happy to announce that EyeWorld is launching a regular column to present and discuss your responses from the annual ASCRS Clinical Survey. ASCRS first conducted this survey in 2013 as a way to better understand our members' clinical experiences, opinions, and practice patterns. This information is reviewed and analyzed by our six Clinical Committees (cataract, refractive, cornea, glaucoma, retina, young ophthalmologists/residents), and helps ASCRS to more appropriately target our yearlong educational efforts. For example, at the 2014 ASCRS•ASOA Symposium & Congress in Boston, more than 40 lectures and many of the ASCRS Clinical Committee symposia were based on findings from the 2013 ASCRS Clinical Survey. Through this new column, we plan to share key findings and discussion points from the survey with EyeWorld readers throughout the year. More than 1,500 ophthalmologists completed the 2014 ASCRS Clinical Survey either at the annual meeting in Boston or online following the conference. We are grateful that so many of you took the time to respond. Developed with the input of our Clinical Committees, the survey asked relevant questions relating to practical, everyday clinical situations. The 2014 survey captured 267 measurable data elements in more than 10 different clinical areas. For example, members were surveyed regarding their: • Rate of posterior capsule rupture during cataract surgery • Management of residual refractive error in premium refractive IOL patients • Threshold for intervention with toric IOL misalignment • Opinions and experience with laser-assisted cataract surgery • Prevention of post-cataract surgical inflammation • Management and prevention of macular edema • Management of glaucoma patients needing cataract surgery • Outcomes and enhancement rates with laser keratorefractive surgery • Perceived incidence of ectasia with laser keratorefractive surgery • Use of intravitreal injections • Opinions and experience with advanced tear film diagnostics • Management of dry eye and meibomian gland disease In the new EyeWorld column, we will present specific results from the 2014 survey that relate to each month's cover focus. We will then ask experts and Clinical Committee members to discuss the findings in light of their own experience and recommendations. In addition, look for a special EyeWorld supplement this fall that will summarize and highlight key results from the 2014 survey. These annual member surveys will continue to guide the ASCRS leadership in both the design and content of future educational programs, such as symposia, publications, "white" papers, regional meetings, and online education. EW See page 46 for the first installment of this new column.