6 Hepatic Venous Malformation

Clinical Presentation

A 36-year-old man presents with mild abdominal pain.

Fig. 6.1 (A–E) Axial contrast-enhanced CT images show an irregular linear, hyperattenuating lesion located peripherally within the liver. The lesions appear in close proximity to hepatic veins and portal venous branches and show similar attenuation as the opacified vessels. These findings are indicative of venous malformation.

Radiologic Findings

Axial contrast-enhanced computed tomography (CT) images (Fig. 6.1) show two different hyperattenuating, irregularly shaped lesions located peripherally within the hepatic parenchyma, in close proximity to the hepatic veins and the branches of the portal vein. These vessels do not taper peripherally as they are supposed to do but appear otherwise quite prominent. There is early opacification of hepatic veins. Both the lesions present the same attenuation of vessels consistent with vascular perfusion anomalies.

Diagnosis

Hepatic venous malformation

Differential Diagnosis

Hepatocellular carcinoma (HCC)
Benign hypervascular lesions (adenoma, focal nodular hyperplasia [FNH], hemangioma)
Hypervascular metastases (neuroendocrine neoplasms: islet cell tumors, carcinoid; breast carcinoma, renal cell carcinoma)
Perfusion anomalies of hepatic parenchyma due to inflammatory changes or arteriovenous fistulas as described after percutaneous catheter procedures (radiofrequency thermal ablation [RFTA], transarterial chemoembolization) or transplantation

Discussion

Background

The liver benefits from a dual blood supply: the arterial system accounts for 25% of the total amount, and the portal vein provides the remaining 75%. These two systems are not independent but intimately connected by means of transsinusoidal, transvasal, and transplexal routes. As soon as vascular disorders occur, the dual blood supply undergoes hemodynamic changes concerning both volume and direction of the blood flow. Perfusion alterations represent a relatively common cause of pseudolesions at cross-sectional imaging; thus, radiologists should be aware of these vascular disorders when reading liver CT.