【摘要】 目的 探讨双能量CT(DECT)120 kVp融合图像中肝脏强化程度达50 HU时基于去脂体质量(LBW)调整的碘剂量。方法 患者行肝脏DECT增强扫描,对比剂碘剂量17.1 g I/m~2体表面积(BSA),注射时间25 s。计算每克碘肝脏平均强化(MHE/I)及基于LBW调整的肝脏平均强化[aMHE=MHE/(I/LBW)]。LBW与MHE/I相关系数的比较采用Z检验。碘剂量与MHE的关系采用线性分位数回归分析。结果 80 kVp及120 kVp融合图像中,MHE/I女性组分别为(3.86±0.60) HU/g I、(2.18±0.35)HU/g I,男性组分别为(3.36±0.51)HU/g I、(1.96±0.27)HU/g I;aMHE女性组分别为(0.144 9±0.018 0)HU/mg I/kg LBW、(0.082 1±0.012 5) HU/mg I/kg LBW,男性组分别为(0.172 7±0.019 0) HU/mg I/kg LBW、(0.101 3±0.010 2) HU/mg I/kg LBW。MHE/I女性组高于男性组,aMHE女性组低于男性组(P<0.05)。120 kVp融合图像总体组、男性组、女性组碘剂量分别为571、548、608 mg I/kg LBW时,MHE第0.5分位数达50 HU;相应地,723、585、684 mg I/kg LBW可使MHE第0.25分位数达50 HU,476、498、529 mg I/kg LBW可使MHE第0.75分位数达50 HU。结论 120 kVp融合图像不同分位数水平肝脏充分强化的基于LBW的碘剂量,可以作为肝脏DECT增强扫描的对比剂应用方案。更多还原

【Abstract】 Objective To determine the optimal iodine dose adjusted based on lean body weight(LBW) when achieved an enhancement of50 HU in hepatic attenuation at blended 120 kVp of dual-energy CT(DECT).Methods All patients underwent hepatic contrast-enhanced DECT,body surface area(BSA)-tailored iodine dose of contrast media were 17.1 g I/m~2,fixed injection duration were 25 s.Mean hepatic enhancement per unit of iodine(MHE/I) and adjusted mean hepatic enhancement(aMHE) EaMHE=MHE/(I/LBW)] were calculated.Linear quantile regression was performed to evaluate the relationship between iodine dose and MHE,and the correlation coefficients between LBW and MHE/I were compared with Z test.Results MHE/I showed higher in women group than in men group:80 kVp,(3.86±0.60) HU/g I vs(3.36±0.51) HU/g I(P<0.05);blended 120 kVp,(2.18±0.35) HU/g I vs(1.96 ±0.27) HU/g I(P<0.05).aMHE showed lower in women group than in men group:80 kVp.(0.144 9±0.018 0) HU/mg I/kg LBW vs(0.172 7±0.019 0) HU/mg I/kg LBW(P<0.05);blended 120 kVp,(0.082 1 ±0.012 5) HU/mg I/kg LBW vs(0.101 3±0.010 2) HU/mg I/kg LBW(P<0.05).MHE for quantile 0.5 was estimated to be 50 HU at blended 120 kVp,when the iodine doses for total population group,men group and women group were 571,548 and 608 mg I/kg LBW.respectively;corresponding,at quantile 0.25,iodine doses were 723,585 and 684 mg I/kg LBW,respectively;and at quantile 0.75,iodine doses were 476,498 and 529 mg I/kg LBW, respectively.Conclusion The required iodine dose might be determined for contrast-enhanced DECT of liver,based on the dose per unit of LBW that provided adequate hepatic enhancement in different quantile levels at blended 120 kVp.更多还原