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by Bret Fisher, MD Blue light filtering IOLs: I'm a believer Innovative technologies designed to improve outcomes Supplement to EyeWorld Daily News, Monday, April 20, 2015 This supplement is sponsored by Alcon. E arly in my experience as a cataract surgeon, I had the subjective impression that the yellow appearance of the lens implant that contained a chromophore was not as aesthetically appealing and might even be a functional limitation of the lens. I wondered why we would take out something yellow and then put something yellow back in. This was my completely unscientific, sub- jective bias or approach to forming an impression of the chromophore early on. In fact, when we first start- ed using Alcon lenses, when there was a choice between the same lens with or without the chromophore, I would always specify without the chromophore, thinking that I was getting a better lens or doing some- thing better for my patients, without any scientific justification. Over the years, there have been a number of studies and a lot of discussion about the issue of blue light filtration. Like many surgeons, I followed that with interest, and over time, I began to see that the weight of scientific evidence seemed to be on the side of blue light filtration and enhancing the visual performance of a lens and the visual performance of my patients' eyes. The initial studies that caught my attention were the driving simula- tion studies first by Hammond and coworkers 1 and then by Gray and co-authors. 2 These studies were the first to demonstrate a real-world benefit for patients who had re- ceived intraocular lenses with blue light filtration. Prior to these publications, most of the purported benefit of blue light filtration had been for long-term macular protection, an effect that had been difficult to demonstrate in the absence of large long-term studies. Other studies followed, including studies that looked at the question of the safety of blue light filtration, especially relating to sleep and circadian rhythm. The excellent review article by Henderson and colleagues 3 was a very comprehen- sive review of the literature until that point, with the conclusion that blue light filtration was not harmful. Other studies and review articles have followed, with the balance of scientific opinion continuing to show benefit from the addition of the chromophore and no harm. I was also aware that many of my col- leagues who I respected were using implants with blue light filtration and were reporting good results. Based on all of this, I made the deci- sion to switch to blue light filtration for my patients. What drove home the impor- tance of blue light filtration, though, was a recent study that I was fortu- nate enough to participate in. 4 The purpose of the study was to evaluate the within-eye visual benefit of blue light filtering among pseudophakic eyes previously implanted with IOLs largely transparent to visible wave- lengths. The study included 154 pseudophakes with no blue light filtering IOL. All patients had bilat- eral pseudophakia 3 or more months after surgery, both eyes had a best corrected visual acuity of 20/40 or better, and no eyes had ocular pathology/degeneration. This was the first study that ever looked at within-eye comparisons as opposed to comparing 2 different eyes from the same patient or groups of eyes from different patients. This study evaluated the same eye from the same patient and compared a clear lens and then a clear lens plus a blue light filter that would simulate the transmission through the chromophore present in the AcrySof platform (Alcon, Fort Worth, Texas). The results were significant and quite impressive. The addition of the blue light filter provided faster photostress recovery time compared to the placebo filter among pseudophakes with IOLs that are largely transparent to visible light. The difference in photostress recovery time between the blue light filter and the placebo filter was 1.37 seconds. The addition of the blue light filter provided greater glare disability threshold compared to the placebo filter among pseudophakes with IOLs that are largely transparent to visible light. The difference in the glare disability threshold was 0.12 log unit. Visual acuity and pupil size were similar with blue light filtering and placebo filters. The corrected visual acuity was 0.05±0.11 logMAR for blue light filtering and 0.05±0.10 for placebo. Pupil size was 3.54±0.80 for blue light filtering and 3.52±0.79 for placebo. No adverse events or medical defects were reported in the study. This means that in situations where a person is driving under a bright mid-day sun or is looking into oncoming headlights, filtering the blue light could improve visual performance, although additional studies would be required to demon- strate the direct functional benefit of blue light filtering. References 1. Hammond B, et al. Contralateral compar- ison of blue-filtering and non-blue-filtering intraocular lenses: glare disability, heterochro- matic contract, and photostress recovery. Clin Ophthalmol. 2010;4:1465–1473. 2. Gray R, et al. Reduced effect of glare disability on driving performance in patients with blue light filtering intraocular lenses. J Cataract Refract Surg. 2011;37:38–44. 3. Henderson B, et al. Blue-blocking IOLs: a complete review of the literature. Surv Ophthalmol. 2010;55(3):284–289. 4. Hammond B. Attenuating photostress and glare disability in pseudophakic patients through the addition of a short-wave absorb- ing filter. Journal of Ophthalmology. 2015; vol. 2015, article ID 607635. Dr. Fisher is in private practice at the Eye Cen- ter of North Florida in Panama City, Fla. He can be contacted at bfisher@eyecarenow.com. This supplement was produced by EyeWorld and sponsored by Alcon. The doctors featured in this supplement received compensation from Alcon for their contributions to this supplement. Copyright 2015 ASCRS Ophthalmic Corporation. All rights reserved. The views expressed here do not necessarily reflect those of the editor, editorial board, or the publisher, and in no way imply endorsement by EyeWorld or ASCRS. Bret Fisher, MD Contents Blue light filtering IOLs: I'm a believer 1 Correcting astigmatism at the time of cataract surgery 2 Correcting astigmatism with the AcrySof IQ Toric IOL 3 Apodization and light distribution of the ReSTOR 4 Topography-guided LASIK: A paradigm shift in refractive laser treatment 5 Important product information 7 digital.eyeworld.org The news magazine of the American Society of Cataract & Refractive Surgery

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