A Comprehensive Approach to Hepatic Vascular Disease

Abstract

The liver has a complex vascular supply, which involves the inflow of oxygenated blood through the hepatic artery (systemic circulation) and deoxygenated blood through the portal vein (portal circulation), as well as the outflow of deoxygenated blood through the hepatic veins to the inferior vena cava. A spectrum of vascular variants can involve the liver. Some of these variants may result in areas of enhancement that can mimic more serious pathologic conditions. In this article, the authors discuss a spectrum of variants and pathologic conditions that may involve the liver vasculature. These include variants, anomalies, and diseases involving the portal vein, such as rudimentary portal vein, thrombosis, cavernous transformation, thrombotic angiitis, thrombophlebitis, transient hepatic attenuation difference or transient hepatic intensity difference, portal venous aneurysm, and portal vein gas. The hepatic artery can be involved by various diseases, including thrombosis, stenosis, and aneurysm or pseudoaneurysm. Unusual "third inflow" sources of venous inflow are also discussed, including aberrant right gastric vein, aberrant left gastric vein, epigastric-paraumbilical veins, and cholecystic vein. A spectrum of variants and diseases involving the inferior vena cava and hepatic veins, including thrombosis, Budd-Chiari syndrome, veno-occlusive disease, stenosis, torsion, congestive hepatopathy, and peliosis hepatis, are discussed. Vascular shunts are illustrated, including portosystemic shunts (intra- and extrahepatic), arterioportal shunt, shunts of hereditary hemorrhagic telangiectasia, and acquired arteriovenous fistula. Familiarity with the pathogenesis and imaging features of these vascular entities can aid radiologic diagnoses and guide appropriate patient management. RSNA, 2017.

Hepatofugal Portal Venous Flow: From Normal to Pathological

“…These patients have a significantly lower survival rate than those with a forward portal flow [4]. The mechanism can be explained with the alteration of the parenchyma, the development of fibrosis, the increase in the vascular hepatic resistance and the development of both small hepatic vein obstruction and diffuse arterio-portal shunts (Figure 5a, 5b) [1]. In the early stages of cirrhosis, the peak systolic velocity drops below 20 cm/s in the MPV.…”

“…Non-forward portal flow in cirrhotic patients is a sign of advanced portal hypertension and advanced liver function impairment [1]. These patients have a significantly lower survival rate than those with a forward portal flow [4].…”

Diffuse Liver Disease: Cirrhosis, Focal Lesions in Cirrhosis, and Vascular Liver Disease

“…A thrombus in the portal vein can be either bland or through venous invasion from adjacent malignancies. Several causes lead to thrombosis of the portal vein system such as cirrhosis, hypercoagulable states, trauma, or abdominal tumors [21]. Disruption of the portal venous endothelium can occur in intra-abdominal inflammatory processes such as chronic inflammatory bowel disease, schistosomiasis, and pylephlebitis leading to portal venous thrombosis [11].…”

“…21.5), also known as portal cavernoma (PC). At ultrasound it appears as a mass of veins in the porta hepatis with hepatopetal flow that lacks the normal respiratory variation of the portal vein [21,22]. PC represents a portoportal collateral pathway that substitutes for a thrombosed portal vein.…”

Imaging of pathology involving the space around the hepatic veins: "perivenous pattern"

“…The imaging findings are generally nonspecific; however, periportal edema, ascites, gallbladder wall thickening, heterogeneous parenchymal enhancement and hepatomegaly are suggestive imaging features when detected. Sonographic imaging findings are nonspecific, but reversal of flow in portal veins may be detected in some patients (21,22). The presence of narrowed right hepatic vein caliber is also a reported CT finding (23).…”