RESUMO
Objective ToevaluateimagequalityoflowerextremityCTAoflowradiationdoseandlowcontrastmediumprotocol withsinogram-affirmediterativereconstruction(SAFIRE).Methods Thisstudyincluded116patientswhoreferredtolowerextremityCT angiographyusinga128-sliceCTscanner.Accordingtovoltageandcontrastmediumconcentration,patientsweredividedintofour groups:100kV+350mgI/mL,100kV+320mgI/mL,100kV+300mgI/mL,80kV+CarekV+300mgI/mL.Imagereconstructionunderwent conventionalfilteredback-projection (FBP)andSAFIREtechniqueineachprotocoltocompareSNR,CNRofarterialimages.Results Comparisonoftwosubgroupsinthesamegroup,SAFIREhadsignificantlyhigherimagequalitythanFBP.Comparisonamong groupsshowed:imagequalityinlowcontrastmediumandlowradiationdoseSAFIREgroupcouldreachsimilarorbetterthanthatin higherdoseFBPgroup.SAFIREcouldreduceimagenoiseandimproveimageSNRandCNR.Conclusion InlowerextremityCTA, 80kV+CarekV,300mgI/mLcontrastmediumwithSAFIREexamineprotocolcouldreducecontrastmediumconcentrationandradiationdose withnocompromiseddiagnosticdemand.