AIM: To investigate the effects of mitomycin C(MMC)on corneal endothelial cells at different exposure time during laser-assisted subepithelial keratomileusis(LASEK).

METHODS: Patients who received LASEK were included and divided into Group T1(15s≤t≤45s)and T2(5sRESULTS: A total of 196 eyes of 98 patients were included with 98 eyes in Group T1 and 98 eyes in Group T2. With the exception of peripheral ACA, central CV and HEX in Group T1 and T2, which significantly changed at 1wk after the surgery(P<0.05), there was no significant difference in central and peripheral parameters within both groups or between the groups(P >0.05).

CONCLUSION: Although transient acute changes in central CV and HEX and peripheral ACA were observed, there is no significant effect on the long-term corneal health status when MMC is applied in a reasonable time range in LASEK surgery.