AIM:To evaluate the clinical effects of femto-LASIK using new Ziemer LDV Z6 femtosecond laser machine(Z6).

METHODS:Two-hundred cases(400 eyes)was randomly separated into two groups: Group A included 200 eyes which corneal flaps were made by Z6, and Group B included rest of 200 eyes which corneal flaps were examined by a traditional Ziemer LDV CrystalLine femtosecond laser machine(CrystalLine). Visual acuity, slit lamp, refraction, Sim-K average, intraocular pressure(IOP), non-invasive tear break-up time(NIAvg-BUT), operation difficulty and complications were compared between two groups preoperatively and postoperatively.

RESULTS:There was no significant differences between two groups in visual acuity, refraction, Sim-K average, IOP and NIAvg-BUT either preoperatively or 6mo postoperatively(P>0.05). Although there were significant differences in operation difficulty and complications were found between two groups(P<0.05), there was no serious complication in any group. Furthermore, a clear demarcation line could be observed in the cornea of Group A postoperatively.

CONCLUSION:More careful and strict requirements are needed when using the new Z6 femtosecond laser for corneal flaps.