Visual recovery after small incision lenticule extraction (SMILE) in relation to pre-operative spherical equivalent

Abstract

Purpose To assess visual recovery after small incision lenticule extraction (SMILE) in relation to pre-operative spherical equivalent. Methods Two hundred fourteen eyes of 107 patients were enrolled. Following surgery, patients were examined pre-operatively, 1 day, 2 weeks, 1 month and 3 months later. High myopia was defined as pre-operative spherical equivalent =?-?5 D. A linear mixed-effects model was used. Results Mean ± standard deviation pre-operative spherical equivalent was -?5.30?±?1.36 D that reduced significantly to 0.04?±?0.70 D (p?<?0.001) at 1 month and -?0.02?±?0.66 D (p?<?0.001) at 3 months. Mean pre-operative LogMAR uncorrected distance visual acuity ± SD was 0.97?±?0.09 that improved significantly to 0.04?±?0.06 at 2 weeks (p?<?0.001), 0.01?±?0.04 at 1 month (p?<?0.001) and 0.01?±?0.04 at 3 months (p?<?0.001). Eighty-eight eyes (41.2%) had uncorrected distance visual acuities of 0.0 at 1 day, 154 eyes (72.0%) at 2 weeks,194 eyes (90.7%) at 1 month and 199 eyes (93.0%) at 3 months. Significantly more eyes with low myopia (>?-?5 D) achieved acuities of 0.0 at 1 day and 2 weeks (p?=?0.041 and p?<?0.001). Post-operative acuities were not associated with refractive targets, laser cut energy settings or other variables. Two hundred nine eyes (97.7%) were within ±?0.5 D of target and 213 eyes (99.5%) were within ±?1 D. Conclusions SMILE for low myopia had faster visual recovery in the early post-operative period with no significant differences between groups detected by 1 and 3 months.