【摘要】 目的 研究MR多回波Dixon(ME Dixon)及T2校正多回波磁共振波谱（HISTO）序列定量评估肝脏脂肪变性的相关性，并探讨肝纤维化阶段对其的影响。材料与方法 27只新西兰大白兔随机分为高脂组22只和对照组5只，行ME Dixon和HISTO序列检查，测量肝脏质子密度脂肪分数（PDFF）。应用HE染色、Masson染色及普鲁士蓝染色观察两组肝脏脂肪肝分级、纤维化分级及铁沉积分布，并经酸水解法获得肝脏脂肪含量（LFC），比较两个序列PDFF值的相关性，肝脏脂肪肝分级、两个序列PDFF值与LFC的相关性，以及不同纤维化阶段ME Dixon-PDFF、HISTO-PDFF与LFC的关系。结果 所有实验兔的ME Dixon-PDFF与HISTO-PDFF值呈高度正相关（r=0.916,P<0.05），且具有高度一致性（ICC=0.952,95%CI 0.883～0.980）。肝脏脂肪肝分级、ME Dixon-PDFF、HISTO-PDFF均与LFC呈正相关（r=0.837、0.818、0.723,P<0.05）。实验兔肝在无或早期纤维化阶段（F0、F1）,ME Dixon-PDFF、HISTO-PDFF与LFC呈高度正相关（r=0.977、0.966,P均<0.05）；在进展期及晚期肝纤维化阶段（F2～F4）,ME Dixon-PDFF、HISTO-PDFF与LFC均无相关性（P>0.05）。结论 使用ME Dixon及HISTO序列可以定量评估LFC，两者具有高度一致性，纤维化的存在会使其定量下降。更多还原

【Abstract】 Purpose To evaluate the correlation and accuracy of quantitative assessment of hepatic steatosis via MR multi-echo Dixon(ME Dixon) and T2-corrected multi-echo magnetic resonance spectroscopy(HISTO) sequences, and to explore the effect of hepatic fibrosis stage on hepatic steatosis. Materials and Methods Twenty-seven New Zealand White rabbits were randomly divided into high-fat group(n=22) and control group(n=5). Liver proton density fat fraction(PDFF) was measured via ME Dixon and HISTO sequence examination. The hematoxylin-eosin staining, Masson staining and Prussian blue staining were used to observe fatty liver grade, fibrosis grade and iron deposition distribution. The liver fat content(LFC) was obtained by acid hydrolysis method. The correlation of PDFF values between the two sequences,fatty liver grade, the correlation between PDFF values of ME Dixon and HISTO sequences and LFC, the relationship between ME Dixon-PDFF,HISTO-PDFF and LFC in different fibrosis stages were further compared, respectively. Results There was a high positive correlation between the ME Dixon-PDFF and HISTO-PDFF values in all experimental rabbits(r=0.916, P<0.05), with a high degree of consistency(intraclass correlation coefficient, ICC=0.952, 95% CI 0.883-0.980). Fatty liver grade, ME Dixon-PDFF, HISTO-PDFF were all positively correlated with LFC(r=0.837, 0.818 and 0.723, respectively, all P<0.05). In the absence or early fibrosis stage(F0, F1), there was a high positive correlation between ME Dixon-PDFF, HISTO-PDFF and LFC(r=0.977, 0.966, all P<0.05). In the advanced fibrosis stage and end stage(F2-F4), there was no correlation between ME Dixon-PDFF, HISTO-PDFF and LFC(all P>0.05). Conclusion PDFF measurement via ME Dixon and HISTO can quantitatively evaluate hepatic steatosis with high consistency, however, the presence of fibrosis could reduce the quantitative accuracy.更多还原