3.0T磁共振R2^＊值在肝纤维化诊断及分期中应用价值初探

Value of 3.0T MRI R2~＊ values in diagnosing and staging of liver fibrosis：a preliminary clinical study

目的:探讨磁共振R2*值在肝纤维化诊断与分期中的应用价值。方法:分别对8例健康志愿者和36例肝脏穿刺病理证实的肝纤维化患者、4例临床明确诊断肝硬化患者进行3.0T磁共振血氧水平依赖成像(BOLD-MRI),重建R2*map并测算肝脏平均R2*值,采用非参数Spearman检验分析R2*平均值与病理肝纤维化分期的相关性、采用Dunnett T3检验及Mann-Whitney U检验分析不同纤维化分期的组间差异,采用ROC曲线评价R2*平均值预测肝纤维化的效能。结果:正常志愿者组、肝纤维化组的R2*平均值分别为(47.63±5.98)Hz、(60.11±12.18)Hz。随着纤维化分期的进展,R2*平均值逐渐增大,R2*平均值与肝纤维化分期呈正相关(r=0.698,P<0.01)。不同纤维化分期的肝脏R2*平均值的差异有统计学意义(F=17.05,P<0.001),R2*平均值在S0与S1、S2、S3、S4,S1与S2,S2与S3之间的差异均有统计学意义(P≤0.05)。R2*平均值预测肝纤维化≥S1期的能力优于预测肝纤维化≥S2期、≥S3期、≥S4期,曲线下面积0.927,敏感度0.966,特异度0.737(R2*≥49.32 Hz)。结论:肝脏BOLD-MRI的R2*值可反映肝纤维化严重程度,是区分肝纤维化及其分期较为敏感的方法,有用于临床肝纤维化评价的潜能。

Objective： To study the value of MRI R2＊ values in diagnosing and staging liver fibrosis.Methods： Eight healthy volunteers and 36 pathologically proved and 4 clinically proved liver fibrosis patients were enrolled,they were scanned by 3.0T MR unit with BOLD-MR sequence,R2＊ maps were reconstructed and mean R2＊ values were calculated.Correlation between stages of fibrosis and R2＊ values with non-parameter Spearman test were analyzed,and the R2＊ values of stages were compared with Dunnett T3 test and Mann-Whitney U test,ROC curve was conducted to evaluate R2＊ values for prediction of fibrosis and its stage.Results： Mean R2＊ values of healthy volunteers and liver fibrotic patients were（47.63±5.98） Hz,（60.11 ±12.18） Hz respectively.Mean R2＊ values increased during the progression of the liver fibrosis progression,and were positively correlated with the stage of liver fibrosis（r=0.698,P0.01）.There were significant differences of R2＊ values among the stages of liver fibrosis（F=17.05,P0.001）,and group S0 versus S1,S2,S3,S4,and S1 versus S2,and S2 versus S3（P 0.05,all）.Predictor for S1 or greater is better than predictor for S2 or greater,S3 or greater and S4 or greater,with the AUC 0.927,the sensitivity was 0.966 and the specificity was 0.737（R2＊ ≥49.32 Hz）.Conclusion： BOLD-MRI R2＊ values can reflect the severity of fibrosis,are sensitive and specific in detecting liver fibrosis and distinguishing different stages of fibrosis,and have the potential value in further clinical diagnosis.