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.
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。.
Keywords: Iron deposition; Magnetic resonance imaging; Nonalcoholic fatty liver disease; R2*.