Comparison of different femtosecond laser refractive surgeries on higher-order aberrations

This study aimed to investigate the effects of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) on higher-order aberrations in patients. 56 cases (112 eyes) undergoing refractive surgery in our hospital were selected in this study, all patients were randomly divided into femtosecond laser-assisted in situ keratomileusis group (LASIK group) and small incision lenticule extraction group (SMILE group) with each group of 28 patients (56 eyes) by random digital table method. Higher-order aberrations of anterior corneal surface, including total higher-order aberration, spherical aberration, horizontal coma and vertical coma were detected at different time points (the 1st week, 1st month, 3rd month and 6th month) before and after surgery, and the changes between preoperative and postoperative values were compared. Postoperative total higher-order aberrations and spherical aberrations at different time points in both groups were significantly increased while vertical coma was obviously decreased when compared with preoperative data (P<0.05). Postoperative horizontal coma at different time points in SMILE group was increased (P<0.05) while there was no significant change in horizontal coma in LASIK group (P>0.05). Both postoperative total higher-order aberrations and spherical aberrations at different time points and their change values before and after surgery in SMILE group were significantly lower than those in LASIK group (P<0.05). In conclusion, changes in higher-order aberrations induced by femtosecond laser-assisted SMILE are less than that induced by FS-LASIK, so the visual quality of patients can be improved in certain scenarios.