Optimized Femto-LASIK Maintains Preexisting Spherical Aberration Independent of Refractive Error

摘要

Traditionally, wavefront-guided corneal ablation treatments have produced higher order aberrations (HOAs) proportionate with the amount of laser treatment. With the advent of wavefront-optimized systems such as the WaveLight Allegretto Wave Eye-Q excimer laser system (Alcon Laboratories Inc, Ft Worth, Texas), midperiph-eral ablation within the optical zone is treated to a greater extent to compensate for losses, hence improving outcomes. The WaveLight FS200 femtosecond laser (Alcon Laboratories Inc) was approved by the United States Food and Drug Administration (US FDA) in October 2010 to generate LASIK flaps. Initial studies demonstrated highly reproducible, three-dimensional, tissue-cutting capabilities. George et al previously described promising outcomes with reduced spherical aberration for a cohort of patients undergoing wavefront-optimized profile treatments utilizing the WaveLight Allegretto Wave Eye-Q excimer laser (400-Hz) and IntraLase FS60 (Abbott Medical Optics, Santa Ana, California) femtosecond laser. Although previous authors have reported an increased incidence of HO As in high myopic corrections, others have found that even the creation of the LASIK flap contributes to HOAs, as it induces stromal bed irregularities and biome-chanical tissue changes. In particular, the use of some mechanical microkeratomes seems prone to create these aberrations with greater frequency.