Portal System Thrombosis

Portal (and splenic) vein thrombosis may be primary or more commonly secondary. There are a multitude of causes some of which are listed.
1. Idiopathic
2. Secondary to tumour (including HCC, Pancreatic and Cholangiocarcinoma)
3. Trauma
4. Abdominal sepsis
5. Pancreatitis
6. Ascending cholangitis
7. Myeloproliferative disorders
8. Hypercoagulable syndromes
9. Severe dehydration
10. Cirrhosis with portal hypertension
Primary imaging investigations of choice include ultrasound and contrast enhanced CT.
The appearances on CT are similar to those found at CTPA for a pulmonary embolus with a filling defect within the portal vein. Consideration should be made to identify potential causes as well as complications on the same imaging study, such as pancreatitis, splenomegaly and varices.
References:
1. Radiology Review Manual, Danhert, p736.
2. Portal Vein Thrombosis, Ali Nawaz Khan, emedicine.com
Credit: Dr Ian Bickle
http://www.radpod.org