简介：AIM:Tocomparetheregularityandaccuracyoflaserinsitukeratomileusis(LASIK)flapscreatedbytheZiemerFEMTOLDV'Classic'(Ziemer'Classic')andZiemerFEMTOLDVCrystalLinefemtosecondlaser(ZiemerCrystalLine).METHODS:Fourier-domainopticalcoherencetomography(RTVueOCT)wasusedtomeasurethemorphologyof200LASIKflapsof100consecutivepatientscreatedwiththeZiemerClassic(100flaps)ortheZiemerCrystalLine(100flaps)atoneweekpostoperatively.Flapthicknesswasevaluatedat36specifiedmeasurementpointsoneachflap.Forallprocedureswithbothlasers,thenominalflapthicknesswas110μm.RESULTS:ThemeanflapthicknessoftheZiemerCrystalLinegroup(102.49±2.68μm)wasthinnerthanthatoftheZiemerClassicgroup(107.65±5.09μm)(P<0.01).Averagethicknessofallflapswasuniformwithin4μmatallmeasurementpoints.TheflapsintheZiemerCrystalLinegroupweremoreregularthanthoseintheZiemerClassicgroupwhenmeasuredfromthecentertotheperiphery.Themaximumdeviationfromthenominal110μmof36measurementswas8μmintheZiemerClassicgroup,whileintheZiemerCrystalLinegroupitwas9μm.Withinthe3600measurementsonthe100eyes,differencesgreaterthan20μmwereobserved0.14%intheZiemerClassicgroup,and0.04%intheZiemerCrystalLinegroup.CONCLUSION:TheflapscreatedwiththeZiemerFEMTOLDVCrystalLinefemtosecondlaseraremoreuniformandthinnerthanthosecreatedbytheZiemerFEMTOLDVClassicfemtosecondlaser.