基于MRI的非酒精性脂肪性肝病患者铁沉积的代谢研究

Metabolic study of iron deposition based on magnetic resonance in patients with nonalcoholic fatty liver disease

目的通过磁共振成像(MRI)探讨非酒精性脂肪性肝病(NAFLD)患者肝脏铁沉积与脂肪变的关系。方法163例肝活检患者行肝脏MRI检查,R2*用于测定肝铁含量,基于Dixon的质子密度分数(PDFF)用于测定肝脏脂肪含量,根据肝活检病理结果通过单因素方差分析、相关性分析、受试者操作特征(ROC曲线)等分析临床病例资料、血清学指标、影像学结果之间的关系。结果随着病理脂肪变性分级越高,R2*逐步增高,无脂肪变(<5%),轻度脂肪变(14.95%±8.55%),中度脂肪变(46.30%±9.32%),重度脂肪变(73.86%±6.35%)对应的R2*分别为27.56±4.40,31.06±5.95,38.06±4.80,48.10±5.55(P<0.001),R2*和肝脏脂肪变含量呈正相关(r=0.769,P<0.05),ROC曲线下面积为0.88,截断值为31.77,与肝脏炎症和纤维化相关性不明显。结论R2*可以无创量化评估NAFLD患者肝铁沉积含量,肝脏脂肪变和铁沉积存在明显相关性,随着脂肪变加重,铁沉积也呈加重趋势。

Objective To explore the relationship between liver iron deposition and steatosis in patients with non-alcoholic fatty liver disease(NAFLD)through MRI.Methods 163 cases of liver biopsy underwent MRI examination.R2*was used to measure liver iron content.Dixon-based proton density fat fraction(PDFF)was used to measure liver fat content.One-way ANOVA,r-correlation,ROC curve,and others were used to assess the relationship between clinical case data,serological indices,and imaging results in accordance with the pathological results of the liver biopsy.Results R2*gradually increased as the pathological steatosis grade rose.The R2*that corresponded to no steatosis(<5%),mild steatosis(14.95%±8.55%),moderate steatosis(46.30%±9.32%),and severe steatosis(73.86%±6.35%)were 27.56±4.40,31.06±5.95,38.06±4.80,and 48.10±5.55(P<0.001),respectively.There was a positive correlation between R2*and liver steatosis content(r=0.769,P<0.05).The area under the ROC curve and cut-off value were 0.88 and 31.77,respectively,and there was no distinct relationship with liver inflammation or fibrosis.Conclusion R2*can quantitatively and non-invasively evaluate liver iron deposition in patients with NAFLD.A distinct relationship exists between liver steatosis and iron deposition,and iron deposition tends to increase as the steatosis aggravates.