双低技术联合基于原始数据的迭代重建在下肢动脉CT血管成像中的应用

摘要

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.%目的 评价基于原始数据的迭代重建(SAFIRE)技术对于下肢动脉成像质量的影响,并探讨下肢动脉CTA可行的双低剂量方案.方法 采用128层CT行下肢动脉CTA检查116例患者,根据扫描电压及对比剂浓度的不同分为4组:100kV+350mgI/mL, 100kV+320mgI/mL,100kV+300 mgI/mL,80kV+CarekV+300 mgI/mL.各组数据均进行传统滤波反投影(FBP)及SAFIRE技术图像重建,比较各重建组血管图像的SNR及CNR.结果 同组内,SAFIRE图像优于FBP图像.组间比较,低剂量组SAFIRE图像能够达到或优于更高剂量组的FBP图像质量.SAFIRE技术能有效降低图像噪声并改善图像的SNR、CNR.结论80kV+CarekV、联合SAFIRE重建及300mgI/mL浓度对比剂的扫描方案,能够达到下肢血管病变诊断要求的图像质量,并降低了辐射剂量及对比剂浓度.