Ultrasonography in Liver Vascular Disease

Vascular liver diseases include a heterogeneous group of disorders affecting the micro- and the macro-circulation of the liver. Thrombosis and obstruction of the inflow (portal vein) and/or outflow venous system (Budd-Chiari syndrome), spontaneous porto-systemic shunts, diseases affecting the sinusoids, and hepatic vascular malformations are the most important vascular liver diseases. Thrombosis of the portal venous system and of the hepatic venous system occur most commonly and are potentially life-threatening conditions, while congenital and acquired pro-thrombotic diseases are major causal factors, together with local factors triggering thrombotic events. Despite their overall low prevalence, vascular liver diseases represent the second cause of portal hypertension in the Western world. Imaging techniques are of paramount importance in the diagnostic process, as well as in the follow-up of patients affected by these conditions. In this review, we focus on the role of ultrasonography in the management of vascular liver diseases by highlighting advantages and drawbacks of this imaging technique. In addition, we provide a state of the art presentation of the possibilities offered by ultrasound in the evaluation of vascular and parenchymal features in vascular liver diseases encompassing not only the use of grayscale imaging, but also the application of Doppler ultrasound, the measurement of hemodynamic parameters and the assessment of liver stiffness.