肝脏局灶性增生结节不典型MR影像表现并文献复习

Atypical MR Imaging Findings of Hepatic Focal Hyperplastic Nodules and Review of the Literature

目的对误诊的肝脏局灶性增生结节(FNH)在增强MR肝胆期低信号影像表现及病理基础进行分析。方法经医院伦理委员会同意,回顾性分析2016年1月至2019年6月经钆塞酸二钠(Gd-EOB-DTPA)磁共振增强扫描,经病理证实且肝胆期表现为低信号的FNH,共3例(2例单发,1例多发)。结果影像特征:增强方式,2例单发FNH呈明显持续性强化,1例多发FNH病灶未见明显强化;肝胆期表现为不同程度低信号;正反相位可见不同程度衰减。组织病理:3例FNH均有不同程度脂肪变性,分别为5%,40%,80%;其中多发FNH有部分肝细胞轻度异型改变;1例单发FNH免疫组织化学显示胆管细胞标记物CK7、CK19阴性。结论对于肝胆期表现为低信号的FNH,容易误诊,需结合其他影像学表现来辅助诊断及鉴别肝脏占位性病变。

Objective To investigate the signal manifestation at hepatobiliary phase and pathological basis of misdiagnosed focal nodular hyperplasia(FNH).Methods Retrospective analysis was performed on 3 cases(2 cases were single and 1 case was multiple)of FNH with low signal in hepatobiliary phase confirmed by pathology through GD-EOB-DTPA MRI enhancement examination from January 2016 to June 2019.Results Imaging features:enhancement mode,2 cases of single FNH showed significant persistent enhancement,and 1 case of multiple FNH lesions showed no significant enhancement.Hepatobiliary phase showed different degrees of low signal;The out-phase images are attenuated to different degrees.Histopathology showed that the 3 FNH lesions had different degrees of steatosis(5%,40%,80%,respectively).Multiple cases of FNH have mild atypia in some hepatocytes.In addition,FNH immunohistochemistry showed negative for bile duct cell markers CK7 and CK19 in 1 case.Conclusion For FNH with low signal in hepatobiliary phase,it is easy to be misdiagnosed.Therefore,other imaging manifestations should be combined to assist in the diagnosis and differentiation of hepatic space-occupying lesions.