AIM:To observe the clinical effect of on-flap and off-flap epipolis laser in situ keratomileusis(EPi-LASIK)in ametropia.

METHODS: Sixty-eight myopia patients(136 eyes)receiving surgical treatment were selected and divided into research group and control group according to different therapies. The patients in research group adopted off-flap EPi-LASIK and those in control group adopted on-flap EPi-LASIK. The index like uncorrected visual acuity, diopter and Haze of two groups before surgery, 1wk, 1 and 4mo after surgery was observed.

RESULTS: One month after surgery, the uncorrected visual acuity of research group was 1.33±0.22 while that of control group was 1.22±0.19(P<0.05); Cylindrical diopter of research group was 0.10±0.55D while that of control group was 0.30±0.82D(P<0.05). One week after surgery, Haze of research group was 0.22±0.15 while that of control group was 0.23±0.18(P<0.05).

CONCLUSION:On-flap and off-flap EPi-LASIK are safe and effective surgery approaches in the clinical treatment of ametropia. The presence of corneal epithelial flap has a certain effect in the postoperative clinical outcome at early stage. The impact will be gradually reduced over time.