Femtosecond lasers for laser in situ keratomileusis: a systematic review and meta-analysis

Anne Huhtala,1 Juhani Pietilä,1,2 Petri Mäkinen,1,2 Hannu Uusitalo1–3 1Silmäasema Eye Hospital, 2SILK, Department of Ophthalmology, School of Medicine, University of Tampere, 3TAUH Eye Center, Tampere University Hospital, Tampere, Finland Purpose: The aim of this study was to review and meta-analyze whether there are differences between reported femtosecond (FS) lasers for laser-assisted in situ keratomileusis (LASIK) in terms of efficacy, predictability, and safety as primary outcomes and corneal flap thickness measurements and pre- and postoperative complications as secondary outcomes.Methods: A comprehensive literature search of PubMed, Science Direct, Scopus, and Cochrane CENTRAL Trials Library databases was conducted to identify the relevant prospective randomized controlled trials of FS lasers for LASIK. Thirty-one articles describing a total of 5,404 eyes were included.Results: Based on efficacy, IntraLase FS 10 and 30 kHz gave the best results. Based on predictability and safety, there were no differences between various FS lasers. FEMTO LDV and IntraLase FS 60 kHz produced the most accurate flap thicknesses. IntraLase and Wavelight SF200 had the fewest intraoperative complications. IntraLase, Visumax, and Wavelight FS200 had the most seldom postoperative complications.Conclusion: There were dissimilarities between different FS lasers based on efficacy and intraoperative and postoperative complications. All FS lasers were predictable and safe for making corneal flaps in LASIK. Keywords: femtosecond laser, laser in situ keratomileusis, LASIK, meta-analysi