AIM: To compare the clinical effect, safety and visual outcome after laser in situ keratomileusis(LASIK)using femtosecond laser or a mechanical microkeratome.

METHODS: By retrospective study, 120 cases(240 eyes)of myopia patients had refractive surgery from July 2016 to June 2017. There were 62 cases(124 eyes)were treated with traditional LASIK, and 58 cases(116 eyes)were treated with LASIK using femtosecond laser to create corneal flaps. Visual acuity,corneal flap thickness and aberration were evaluated at 1, 6 and 12mo.

RESULTS: The corneal flap was successfully made in all patients, and the operation was successfully completed. There were no obvious complications during and after the operation. There were no statistical differences between the two groups about visual acuity or refractive error after operation(P>0.05). However,the result of corneal flap thickness in the Femto-LASIK was better than the result in the traditional LASIK(t=26.67, P<0.01). In addition, the added values of spherical aberration, coma aberration and total higher-order aberrations in the Femto group were smaller than those in the traditional group(t=-4.16, -4.92, -22.19; P<0.01). The post operative surface regularity index(SRI)of traditional LASIK was higher than that of Femto-LASIK(0.31±0.09 vs 0.25±0.04; t=6.59, P<0.01).

CONCLUSION: Femtosecond laser made corneal flap is more accurate than lamellar knife flap. Aberrations of femtosecond laser flap LASIK surgery are smaller than the traditional LASIK.Femto-LASIK may provide relatively better visual quality. However, both of the different surgery can result in satisfactory visual acuity.