应用MRI多回波水脂分离技术评估非酒精性脂肪性肝病患者肝脏脂肪含量效能研究*

目的 探讨使用磁共振成像(MRI)多回波水脂分离技术(IDEAL-IQ)诊断非酒精性脂肪性肝病(NAFLD)的效能。方法 2018年2月～2020年2月我院诊治的120例NAFLD患者和65例体检健康人,接受MRI检查,分别采用IDEAL-IQ定量检测肝脏相对脂肪含量(RLC)和采用氢质子磁共振波谱(MRS)检测脂肪分数(FF),NAFLD患者接受肝活检。应用受试者工作特征曲线(ROC)评估IDEAL-IQ和MRS技术诊断NAFLD患者肝脏脂肪变的价值。结果 NAFLD组血清ALT、GGT、TC、TG、RLC和FF水平分别为(54.8±10.6)U/L、(103.1±5.6)U/L、(6.2±0.7)mmol/L、(2.7±0.6)mmol/L、(17.4±9.2)%和(18.0±6.5)%,均显著高于健康人【分别为(25.7±11.4)U/L、(59.7±2.7)U/L、(4.6±0.4)mmol/L、(1.6±0.2)mmol/L、(3.5±1.3)%和(6.2±2.1)%,P＜0.05】;15例肝脏重度脂肪变患者RLC和FF分别为(32.5±4.8)%和(28.6±4.0)%,显著高于39例中度脂肪变患者【分别为(23.1±6.2)%和(20.8±5.1)%,P＜0.05】或66例轻度脂肪变患者【分别为(10.6±3.0)%和(13.9±4.2)%,P＜0.05】;以RLC＞23.7 %为截断点,诊断中重度NAFLD的AUC为0.894,其约登指数为0595,敏感度为88.7%,特异性为70.8%,而以FF＞20.4 %为截断点诊断中重度NAFLD的AUC为0.870,其约登指数为0.910,敏感度为97.0%,特异性为90.0%,显著优于前者(Z=3.025,P＜0.05)。结论 使用MRI IDEAL-IQ技术诊断NAFLD患者肝脂肪变具有一定的实用意义,值得进一步研究。

Diagnostic efficacy of MRI IDEAL-IQ in the evaluation of hepatic steatosis in patients with non-alcoholic fatty liver disease

Objective The aim of this study was to explore the diagnostic efficacy of magnetic resonance imaging (MRI) iterative decomposition of water and fat with echo asymmetry and the least squares estimation quantification sequence (IDEAL-IQ) in the evaluation of hepatic steatosis in patients with non-alcoholic fatty liver diseases(NAFLD). Methods A total of 120 patients with NAFLD and 65 healthy individuals were enrolled in our hospital between February 2018 and February 2020, and all underwent MRI scan. The magnetic resonance spectroscopy (MRS) of hydrogen proton and IDEAL-IQ quantitative indexes, e.g. relative lipid content (RLC) and fat fraction (FF) were obtained. The patients with NAFLD received liver biopsies. The diagnostic efficacy of IDEAL-IQ for hepatic steatosis was analyzed by ROC. Results Serum ALT, GGT, TC, TG, and the RLC and FF in patients with NAFLD were (54.8±10.6)U/L, (103.1±5.6)U/L, (6.2±0.7)mmol/L, (2.7±0.6)mmol/L, (17.4±9.2)% and (18.0±6.5)%, all significantly higher than (25.7±11.4)U/L,(59.7±2.7)U/L,(4.6±0.4)mmol/L, (1.6±0.2)mmol/L, (3.5±1.3)% and (6.2±2.1)%, respectively, P＜0.05] in healthy persons; the RLC and FF in 15 patients with severe hepatic steatosis were(32.5±4.8)% and (28.6±4.0)%, both significantly higher than (23.1±6.2)% and (20.8±5.1)%, P＜0.05] in 39 NAFLD patients with moderate liver steatosis or (10.6±3.0)% and (13.9±4.2)%, P＜0.05] in 66 patients with mild liver steatosis; the AUC was 0.894, with the sensitivity (Se) of 88.7%, the specificity (Sp) of 70.8% as the RLC＞23.7 % was set as the cut-off-value, and the AUC was 0.870, with the Se of 97.0%, the Sp of 90.0% when the FF＞20.4 % was set as the cut-off-value in diagnosing moderate to severe liver steatosis, the latter superior to the former (Z=3.025,P＜0.05). Conclusion The qualitative and quantitative diagnosis of hepatic steatosis as an non-invasive approach in patients with NAFLD by MRI IDEAL-IQ is promising, and warrants further investigation.