EyeWorld Asia-Pacific September 2015 Issue

38 EWAP REFRACTIVE September 2015 Modern LASIK by the numbers by Maxine Lipner EyeWorld Senior Contributing Writer AT A GLANCE • According to the PROWL studies, 98% of patients were satis ed or very satis ed with the procedure. • The iDesign relies on 1,250 data points, honing in on imperfections in the eye for LASIK. • Topography-guided LASIK offers precise primary outcomes and secondary therapeutic potential. Quantifying patient perspectives and beyond J ust how effective is modern LASIK with current state-of-the-art technology? EyeWorld is drilling down on study results that take patients’ perspectives into account, as well as more traditional data. The recent PROWL 1 (Patient- Reported Outcomes With LASIK) and PROWL 2 studies assessed patient satisfaction with wavefront- guided and wavefront-optimized ablations and put numeric perspective on this. The idea behind this two-pronged study was to shine a light on the impact that the surgery has on patients, according to Peter J. McDonnell, MD , William Holland Wilmer professor and director, Wilmer Eye Institute, Johns Hopkins University, Baltimore. Some resistance to refractive surgery goes back to the old days of radial keratotomy. “There have been people who are tremendous adherents, who have had surgery and feel that it is very positive and even transformative for them,” he said. “There has also been a vocal minority of people, however, who feel there have been problems.” When PRK came along, such issues diminished, but with LASIK these concerns resurfaced in some corners. Patients’ perspective “In an effort to generate more light and less heat and to have actual data, efforts have been underway to try to measure more accurately the impact of refractive surgery on patients’ lives,” Dr. McDonnell said, adding that the PROWL study included not only easy-to-measure factors such as visual acuity but also patients’ reports of their ability to function under different circumstances. The study included a military and a civilian population, with the military-based PROWL 1 consisting mostly of young, healthy males, and PROWL 2 more apt to include older civilians, Dr. McDonnell said. These populations were very different. “Young military recruits tend to have fewer issues like dry eye, which may be a particularly important consideration in refractive surgery, and the civilian population tended to be older, more female,” he said, adding that older females in particular are more likely to have dry eyes, which can be problematic for refractive surgery. So examining these two different populations was very helpful. Traditional results from this study at 6 months indicated that following LASIK, 99.5% of patients had 20/20 binocular acuity or better, with 76% attaining acuity of 20/12.5 or better. The study also included patient- reported outcomes, something Dr. McDonnell views as very important. “The way we measure visual acuity on a high contrast acuity chart may be reproducible and consistent among offices, but patients don’t live in our exam lanes,” he said. “They live out in the real world.” If you want to truly know how successfully patients are functioning, why not ask them? That’s what the instruments in the PROWL studies were designed to do. The results gleaned here were encouraging, he said. “While there are some people who report issues like glare and halos early on after surgery, if we look at how people do over time, issues like glare, halos, and ghost images 6 months after surgery were either at or below the level that patients had prior to surgery,” Dr. McDonnell said. “At 6 months, 98% of patients said they were satisfied or very satisfied— only 2% were dissatisfied.” Dr. McDonnell thinks this is reassuring. “Not everyone feels they have perfect outcomes, but the percentages are extremely high of people functioning very well.” He sees the results as substantiating the idea that practitioners are providing patients with outstanding LASIK outcomes. Still, the smart ophthalmologist understands that patient selection and preop education are a key part of the process. “The PROWL studies by no means take away the importance and the duty of surgeons to carefully evaluate patients as surgical candidates,” Dr. McDonnell said. “It doesn’t guarantee wonderful outcomes, but it can reassure us that for appropriate candidates, appropriately performed LASIK has a high margin of safety and a high degree of efficacy.” Evolving approaches In addition to wavefront- guided and wavefront-optimized approaches, other modern LASIK approaches have emerged. In May the iDesign Advanced WaveScan Studio System (Abbott Medical Optics, Abbott Park, Ill.) received U.S. Food and Drug Administration (FDA) approval. This system is used to capture information on any given patient and drives a customized treatment, according to Stephen C. Coleman, MD , in private practice at Coleman Vision Center, Albuquerque, NM. The technology, which uses wavefront diagnostic aberrometry to pinpoint imperfections in the eye, relies on more data points than ever before. “There are currently 1,250 data points that are provided