Correction of myopic astigmatism by small incision lenticule extraction: does laterality matter?

To evaluate the outcome after astigmatic correction of small incision lenticule extraction (SMILE) and to compare the refractive results of right eyes with left eyes. Patients who underwent SMILE surgery in our clinic between 2014 and 2016 (Visumax, Carl Zeiss Meditec, Germany) were retrospectively reviewed. Preoperative and postoperative manifest refractions and corrected and uncorrected visual acuities were evaluated and changes in refractive astigmatism were evaluated by vector analysis. One hundred twenty-one eyes from 82 patients with myopic astigmatism were included. The mean preoperative spherical equivalent was - 6 ± 1.7 (range from - 9.50 to - 1.25) D and the mean cylinderical power was - 1.5 ± 0.6 (range from - 3.75 to - 1.00) D. Postoperatively 71.8% of eyes had < 0.50 D cylinder magnitude. Vector analysis results based on laterality revealed that correction index was 0.87 ± 0.3 for left eyes and 0.72 ± 0.3 for right eyes (p 0.02). This study revealed that SMILE has favorable astigmatic correction affect but left eyes have better outcomes than right eyes.