EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
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EW RESIDENTS 60 November 2014 femtosecond laser-assisted cataract surgery. Am J Ophthalmol 2014;157:426–432.e1. 5. Takács AI, Kovács I, Miháltz K, et al. Central corneal volume and endothelial cell count fol- lowing femtosecond laser-assisted refractive cataract surgery compared to conventional phacoemulsification. J Refract Surg Thorofare NJ 1995 2012;28:387–391. 6. Conrad-Hengerer I, Al Juburi M, Schultz T, et al. Corneal endothelial cell loss and corneal thickness in conventional compared with femtosecond laser-assisted cataract surgery: three-month follow-up. J Cataract Refract Surg 2013;39:1307–1313. 7. Abell RG, Kerr NM, Howie AR, et al. Effect of femtosecond laser-assisted cataract surgery on the corneal endothelium. J Cataract Refract Surg 2014. 8. Suzuki H, Oki K, Takahashi K, et al. Functional evaluation of corneal endotheli- um by combined measurement of corneal volume alteration and cell density after phacoemulsification. J Cataract Refract Surg 2007;33:2077–2082. 9. Mastropasqua L, Toto L, Mastropasqua A, et al. Femtosecond laser versus manual clear corneal incision in cataract surgery. J Refract Surg Thorofare NJ 1995 2014;30:27–33. 10. Doughty MJ, Müller A, Zaman ML. Assessment of the reliability of human corneal endothelial cell-density estimates using a noncontact specular microscope. Cornea 2000;19:148–158. Contact information Uhler: TUhler@willseye.org difference; overall quality of the automated wound could potentially lead to more wound manipulation, chamber instability, instrumenta- tion, and/or viscoelastic prolapse. In another study, phacoemulsification cataract surgeries with automated incisions demonstrated less corneal edema and endothelial cell loss com- pared to cases with manual incisions at postoperative months 1 and 4. 9 The authors acknowledge the limitations of the study include non-randomization, stratification based on ability to pay for FLACS, and the potential inaccuracy and inherent variability of specular microscopy. 10 The sample attrition, or patient dropout, which can lead to unbalancing of the study co- hort, is not reported. Differences in exclusion criteria and dropout between FLACS and PCS groups may have further confounded outcomes. Finally, the study did not report the amount of irrigating fluid utilized or specify the phacoemulsification settings that were used and which could affect endothelial cell loss and limit the generalizability of the results. In the longest follow-up study of FLACS outcomes, Abell and col- leagues' prospective masked-investi- gator non-randomized cohort study demonstrated small but statistically significant short-term differences in postoperative endothelial cell count and corneal edema when comparing FLACS to PCS. Given these results in uncomplicated cases, future stud- ies examining the effect of FLACS on the corneal endothelium could incorporate cases with pre-existing endothelial dysfunction measuring postoperative patient satisfaction, EDTRS visual acuity, contrast sensi- tivity, and retinal point spread func- tion at multiple time points to assess the kinetics of visual outcomes. In the long term, the authors conclude that the small reduction in early postoperative corneal edema and en- dothelial cell loss was not clinically significant. Thus, FLACS appears to have no long-term benefit to corneal integrity over conventional PCS in uncomplicated cases. Underlying this conclusion is the fact that both FLACS and PCS cohorts demonstrat- ed lower CCT at 6 months compared to baseline despite a decrease in endothelial cell density. Considering the continued rise of healthcare expenditures, fur- ther studies examining FLACS will need to evaluate cost-effectiveness. Corneal decompensation is already a rather uncommon adverse event after cataract surgery and the return on investment with FLACS may not be justified for all-comers. However, for cases with a history of trauma, mature cataracts, pseudoexfoliation, or pre-existing endothelial dysfunction, FLACS may have a role if it can be shown to decrease complication rates. We look forward to future studies investigat- ing FLACS outcomes with multiple lens fragmentation settings and incision configurations as well as its utility for complex cases. Acknowledgements The authors would like to thank Robert Bailey, MD, Mark Blecher, MD, Brad Feldman, MD, Julia Haller, MD, Mark Pyfer, MD, Christopher Rapuano, MD, Tara Uhler, MD, and Doug Wisner, MD, for their time and assistance in preparing this manuscript. EW References 1. Lundberg B, Jonsson M, Behndig A. Postoperative corneal swelling correlates strongly to corneal endothelial cell loss after phacoemulsification cataract surgery. Am J Ophthalmol 2005;139:1035–1041. 2. Abell RG, Kerr NM, Vote BJ. Toward zero effective phacoemulsification time using femtosecond laser pretreatment. Ophthalmology 2013;120:942–948. 3. Hayashi K, Hayashi H, Nakao F, Hayashi F. Risk factors for corneal endothelial injury during phacoemulsification. J Cataract Refract Surg 1996;22:1079–1084. 4. Mayer WJ, Klaproth OK, Hengerer FH, Kohnen T. Impact of crystalline lens opacifica- tion on effective phacoemulsification time in Review continued from page 58 Wills Eye Hospital at Thomas Jefferson University residents. Front row (left to right): Joshua Ehrlich, MD, Michelle Wilson, MD, Nina Ni, MD, Alison Huggins, MD, Wen-shi Shieh, MD, Jinali Patel, MD, Faheem Ahmed, MD, Blair Armstrong, MD, Marta Melnyk, MD. Back row (left to right): Michael Cohen, MD, Murtaza Adam, MD, Brian Doyle, MD, Nathan Cutler, MD, Charles Calvo, MD, Pirya Sharma, MD, Brenton Finklea, MD. Not pictured: Alia Durrani, MD, Christine Talamini, MD, Brynn Wajda, MD, Nika Bagheri, MD, Alice Williams, MD, Alessandra Intili, MD, Erin Lally, MD, Margaret Greven, MD Source: Roger Barone