Abstract: 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.

Key words: Perivascular lucency, Viral hepatitis, Tomography, X-ray computer, Magnetic resonance imaging