Total hepatic perfusion by portal system and hepatic arteria as well as its respective average contributions, can be affected for several hepatic processes, such as diffuse liver disease, neoplasm and intrahepatic shunts. Blood flow exams of the liver vessels using Doppler ultrasonography, appeared as a viable, non-invasive and helpful diagnostic method for the hemoportal dynamic evaluation. There are two Doppler ultrasonographic modalities most frequently used in routine for evaluation of the abdominal vessels flow, spectral Doppler imaging and color-flow Doppler imaging. In chronic liver disease, alteration of hepatic complacency occurs because of either fibrosis or cirrhosis, bringing to vascular alterations which provoke an increase in portal pressure. The main indications for this exam are cases suspicious of portal hypertension. Portal hemodynamics is evaluated by measurements of the area, average speed, flow volume and portal vein congestion index. The objectives of this review are to describe the basic physical principles of Doppler ultrasonography and its use for evaluation of portal hemodynamics in dogs.
ultrasonography; Doppler; portal vein; dogs