Diagnostic Approach for Portal Vein Thrombosis

Initial Diagnostic Approach

The European Association for the Study of the Liver and the American Association for the Study of Liver Diseases recommend Doppler ultrasound as the initial investigation for portal vein thrombosis, looking for absence of flow within the portal vein, hyperechoic thrombus visible in the portal lumen, and flow reversal within the portal system 1, 2, 3
Doppler ultrasound is the primary screening tool for diagnosing portal vein thrombosis, with a specific finding of flow reversal within the portal system being 100% specific for clinically significant portal hypertension 1, 2

The American Association for the Study of Liver Diseases recommends proceeding immediately to contrast-enhanced CT scan in the portal venous phase for definitive diagnosis confirmation, assessment of thrombus extension, identification of local causative factors, detection of bowel congestion or ischemia, and evaluation for complications 1, 2, 3
Contrast-enhanced CT scan is used to assess thrombus extension to mesenteric veins and arches, and to identify local causative factors 1, 2

Acute thrombosis can be identified by clinical presentation with abdominal pain and/or systemic inflammatory response, spontaneous hyperdense clot in portal vein lumen on non-enhanced CT, and absence of portal cavernoma formation 1, 2, 3

Contrast-enhanced imaging can distinguish portal vein thrombosis from tumorous portal vein invasion with high accuracy using findings such as arterial phase hyperenhancement within the thrombus and high signal intensity within the obstructed vessel on diffusion-weighted MRI with high b-values 2, 3, 4

The American Association for the Study of Liver Diseases recommends performing CT scan at 6-12 months to assess recanalization of the portal venous system, using Doppler ultrasound early and then every 6 months for ongoing surveillance, and screening for gastroesophageal varices in patients with persistent occlusion 1, 2