AIM: To compare the visual quality of LASIK flap made by femtosecond laser with that by microkeratome.

METHODS: Retrospective case series research was undertaken. In 2011, there were 150 cases(300 eyes)underwent LASIK surgery from June to September. The patients were divided into 2 groups: flap made by femtosecond laser was group 1; flap made by microkeratome was group 2, with 75 cases(150 eyes)for each group. All surgeries performed stroma ablation with EC5000CX-Ⅱ(NIDEK CO., LTD)by the same surgeon. Uncorrected visual acuity(UCVA), diopter before operation and one week, one month, three months after the operation were compared between two groups, as well as corresponding data of the best corrected visual acuity, wavefront aberrations, the scotopic and photopic contrast sensitivity.

RESULTS: The refractive diopter and uncorrected visual acuity between 2 groups had no significant difference at 1 week,1 month and 3 months after operation. Absolute value of C7, RMS3, RMS6 and RMSh of femtosecond laser group were lower compared with microkeratome group at 1 month after operation(P<0.05). C7 and C14 of femtosecond laser group were also lower at 3 months after operation(P<0.05). At 1 week after operation, the photopic and mesopic contrast sensitivity function in two groups decreased for all spatial frequencies, there were statistical differences compared with which before operation(P<0.05). The scotopic and photopic contrast sensitivity of the first postoperative month was increased compared with that of the first postoperative week. Till the third postoperative month, the contrast sensitivity function in two groups restored to preoperative level. The difference showed no statistic significance.

CONCLUSION: LASIK flap made by femtosecond laser can safely and effectively correct myopia and astigmatism. Femtosecond can improve UCVA and visual quality, decrease high order aberration without reducing postoperative contrast sensitivity. Its postoperative outcome is much better than that of LASIK flap made by microkeratome.