肝脏血管周围晕征的影像表现及其临床意义

Imaging manifestations of liver perivascular lucency and its clinical significance

肝脏血管周围晕征(perivascular lucency,PVL)是反映肝脏淋巴液循环异常的一种影像征象,在病毒性肝炎、肝硬化患者中尤为常见,其病理基础是肝脏淋巴液回流受阻和肝脏淋巴液生成增多。随着医学影像技术的迅猛发展,PVL的显示能力明显提高,以CT和MRI为佳,尤其是MRI,其影像特征主要表现为门脉主干及分支、下腔静脉周围的低密度(CT)和长T1长T2信号(MRI)影,形成晕环或轨道样改变,增强扫描无强化。PVL的出现强烈提示病毒性肝炎或肝硬化病情的加重。本文通过查阅近年来PVL的相关文献,对该征象的病理机制、影像表现及临床意义进行综合叙述。

Perivascular lucency(PVL)is an imaging sign that reflects abnormal circulation of liver lymph fluid,It is especially common in patients with viral hepatitis and cirrhosis;The pathological basis is obstruction of hepatic lymphatic fluid return and increased production of hepatic lymphatic fluid.With the rapid development of medical imaging technology,the display capability of PVL has improved significantly,CT and MRI are preferred,especially MRI;The main manifestations are low density(CT)and long T1 long T2 signal(MRI)shadows around the trunk and branches of the portal vein,forming halo or orbit-like changes,and no enhancement in enhanced scans.The appearance of PVL strongly suggests the worsening of viral hepatitis or cirrhosis.In this article,by reviewing the relevant literature of PVL in recent years,a comprehensive description of the pathological mechanism,imaging manifestations,and clinical significance of this sign is made.