AIM: To compare the clinical effect of femtosecond-assisted laser in situ keratomileusis(FS-LASIK)and trans-epithelial photorefractive keratectomy(TransPRK)using 750Hz ablation frequency and smart pulse technology(SPT)in the correction for moderate myopia.

METHODS: A non-randomised, prospective cohort study was conducted on the included 48 patients(90 eyes)treated with FS-LASIK and 47 patients(90 eyes)treated with TransPRK. All eyes were moderate myopia(spherical equivalence -3.00～-6.00D). Both FS-LASIK and TransPRK were performed by Schwind Amaris 750S excimer laser. Visual acuity, refraction and corneal high order aberration were analyzed before and at 6mo after surgery, respectively, to evaluate the surgical efficacy.

RESULTS: The diopters at 6mo after the surgery of FS-LASIK and TransPRK were emmetropic and relatively stable. There was no significant difference in preoperative and postoperative SE between the two groups(P>0.05). The total high order aberration, spherical aberration, and vertical coma at 6mo after surgery in the FS-LASIK group and TransPRK group were significantly higher than those before surgery(all P<0.001), and the total high order aberration and vertical coma in the FS-LASIK group were higher than those in the TransPRK group(all P<0.001). The mean validity index at 6mo after surgery was 1.054±0.172 and 1.082±0.147(t=-0.755, P=0.459)in the FS-LASIK group and TransPRK group, respectively. Moreover, the mean safety index of the FS-LASIK group was 1.009±0.114 at 6mo after surgery, which was significantly lower than 1.124±0.213 of the TransPRK group(t=-2.322, P=0.033).

CONCLUSION: Both FS-LASIK and SPT-guided TransPRK had better postoperative long-term vision. The total high order aberration and vertical coma of patients in the FS-LASIK group were higher than those in the TransPRK group, and the safety index of FS-LASIK was lower than that in the TransPRK group.