单源双能CT成像碘(水)浓度值评估脂肪肝和肝岛血供的价值

摘要

Objective:To investigate the value of iodine concentrations determined by single source dual energy CT in evaluating the blood supply of fatty liver and focal fatty sparing of liver.Methods:Twenty patients underwent spectral CT scan and were diagnosed with fatty liver and focal fatty sparing,were retrospectively collected in this study.The Non-CE CT value,three-phase CE CT value and iodine concentrations of fatty liver background (FLB) and focal fatty sparing (FFS) were measured by two radiologists.Three-phase enhanced ratio was also calculated for FLB and FFS.The bland-altman,linear regression analysis and intraclass correlation coefficient (ICC) were used to evaluate the consistency of measurements taken by two observers.The quantitative data between FLB and FFS were compared by using paired-samples t test and rank sum test.Results:The consistency of measurements between the observers was rated very well (ICC ＞ 0.75).On the unenhanced and enhanced CT scan,the mixing energy CT value and iodine concentrations of FFS were higher than those of FLB (P ＜ 0.001).The three-phase enhanced ratio of FLB was higher than those of FFS,and there was statistical significant difference (P =0.006,P ＜ 0.001 and P ＜ 0.001,respectively).There was no significant difference in the three-phase enhanced ratio of iodine concentrations between FLB and FFS groups (P-0.455,0.279 and 0.279,respectively).Conclusion:The enhanced ratio of iodine concentrations is more reliable in the evaluation of blood supply of fatty liver and focal fatty sparing,and this proved that the appearance of blood supply of fatty liver and focal fatty sparing is about the same.Thus,it provides a certain basis to differentiate between FFS and atypical hypovascular hepatic tumors.%目的:探讨单源双能CT能谱成像的碘(水)浓度值评估脂肪肝和肝岛血供的价值.方法:搜集行能谱CT扫描且诊断为脂肪肝及肝岛的20例患者.由两位放射科医生分别测量同一患者脂肪肝背景和肝岛的平扫及三期增强扫描的混合能量CT值及碘(水)浓度值,计算混合能量CT值及碘(水)浓度值的三期增强率.使用Bland-Altman图、直线回归分析及组内相关系数(ICC)检验两位观察者所测数据的一致性.比较脂肪肝与肝岛平扫、三期增强扫描的混合能量CT值及碘(水)浓度值的差异,比较脂肪肝与肝岛混合能量CT值及碘(水)浓度值三期增强率的差异.结果:两位观察者所测数据的一致性很好(ICC＞ 0.75).平扫及三期增强扫描中,肝岛的混合能量CT值和碘(水)浓度值均高于脂肪肝背景(P值均＜0.001);脂肪肝与肝岛的混合能量CT值三期增强率差异均有统计学意义(P=0.006、P＜ 0.001、P＜0.001);脂肪肝与肝岛的碘(水)浓度值三期增强率差异均无统计学意义(P=0.455、P=0.279、P=0.279).结论:单源双能CT能谱成像碘(水)值增强率评估脂肪肝与肝岛血供更可靠,证实肝岛与脂肪肝血供状态一致,为临床上鉴别肝岛与不典型乏血供肝脏肿瘤提供了相关依据.