磁共振弹性成像与DWI诊断肝纤维化分期

MR elastography and DWI in staging hepatic fibrosis

目的探讨磁共振弹性成像(MRE)与DWI诊断慢性肝病肝纤维化分期的价值。方法 37例慢性肝病患者均接受MRE与DWI(b=0、50、100、150、200、300、500、800s/mm^2)检查,分别测量肝组织弹性值与表观扩散系数(ADC)值,分析其与肝纤维化分期的相关性,采用受试者工作特征曲线(ROC)对二者诊断慢性肝病肝纤维化分期的效能进行比较。结果肝弹性值、ADC值与肝纤维化分期呈线性相关(r=0.932、-0.606,P均<0.001)。不同肝纤维化分期弹性值、ADC值差异有统计学意义(F=39.701,P<0.001;F=5.031,P=0.003)。诊断肝纤维化≥F1、≥F2、≥F3期,MRE的ROC曲线下面积大于ADC值,且差异有统计学意义(P<0.05);诊断F4期两者曲线下面积无统计学差异。弹性值诊断肝纤维化≥F1、≥F2、≥F3、F4期的临界值为2.80、3.11、3.66、3.99kPa,ADC值诊断的临界值为1.16×10^(-3) mm^2/s、1.16×10^(-3) mm^2/s、1.03×10^(-3) mm^2/s、0.97×10^(-3) mm^2/s。结论 MRE对肝纤维化分期诊断价值优于DWI技术,而DWI对进展期肝纤维化及肝硬化有一定的诊断价值。

Objective To explore the value of magnetic resonance elastography （MRE） and DWI in staging diagnosis of liver fibrosis for chronic liver disease. Methods Totally 37 patients with chronic liver disease underwent MRE and DWI （b=0, 50, 100, 150, 200, 300, 500, 800 s/mm2）. Liver stiffness values and ADC values were measured. Correlation of liver stiffness values and ADC values with liver fibrosis stage were analyzed. The efficacy of liver stiffness values and ADC values in staging diagnosis of liver fibrosis were analyzed and compared using the ROC curve. Results There were significant linear correlation of liver stiffness value and ADC value with the stage of liver fibrosis （r=0. 932, -0. 606, both P〈 0. 001）. Liver stiffness and ADC of different fibrosis staging had statistical difference （F= 39. 701, P〈0. 001; F= 5. 031, P=0. 003）. For staging liver fibrosis≥F1, ≥F2, ≥F3, the area under the ROC of MRE was higher than DWI, and the difference was statistically significant （P〈0.05）. The cutoff values of liver stiffness in diagnisis of liver fibrosis ≥F1, F2, ≥F3, F4 were 2.80 kPa, 3.11 kPa, 3.66 kPa, 3.99 kPa, and the cutoff values of ADC were 1.16 × 10-3 mm^2/s, 1.16× 10-3 mm^2/s, 1.03× 10-3 mm^2/s, 0.97× 10-3 mm^2/s, respeetively. Conclusion MRE is better than DWI for the stage of liver fibrosis, hut ADC value also is valuable in diagnosis of advanced liver fibrosis or cirrhosis.