Efficacy, safety, predictability, contrast sensitivity, and aberrations after femtosecond laser lenticule extraction

Abstract

Purpose To compare femtosecond lenticule extraction and small-incision lenticule extraction to treat moderate to high myopia. Setting Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark. Design Prospective clinical single-masked paired-eye study. Methods An intrastromal lenticule was cut by a femtosecond laser and manually extracted. In femtosecond lenticule extraction, a laser in situ keratomileusis-like flap allowed removal of the lenticule, whereas in small-incision lenticule extraction, it was removed through a small incision. Follow-up was 6 months. Results Thirty-five patients were treated with femtosecond lenticule extraction in 1 eye and small-incision lenticule extraction in the other. The mean preoperative spherical equivalent was -7.6 diopters (D) ± 1.0 (SD) (range -6.0 to -9.9 D). After both procedures, 90% of eyes had an uncorrected distance visual acuity of 20/40 or better 1 day postoperatively, increasing to 100% after 6 months. At 6 months, the mean corrected distance visual acuity (CDVA) improved significantly by approximately 1.5 letters on the logMAR chart. No eyes lost or gained 2 lines or more of CDVA after either procedure. The achieved refraction was a mean of -0.04 ± 0.38 D from the attempted refraction after femtosecond lenticule extraction and -0.09 ± 0.39 D after small-incision lenticule extraction. After both procedures, 88% of eyes were within ±0.50 D. Contrast sensitivity was unchanged. The changes in higher-order aberrations were similar. Conclusion The all-femtosecond laser flap-based and cap-based techniques produced almost identical results up to 6 months postoperatively in eyes with moderate to high myopia. Financial Disclosure Dr. Hjortdal received travel reimbursement from Carl Zeiss Meditec AG. No other author has a financial or proprietary interest in any material or method mentioned.