Computed tomographic features of portal vein thrombosis in two cats with splenosystemic shunts.

Two spayed female cats presented with hepatic encephalopathy due to hyperammonaemia. On abdominal ultrasound, concurrent portal vein thrombosis and splenosystemic shunts were suspected in both cats. Computed tomographic angiography clearly detected thrombi as non-contrast enhancing intraluminal structures in the main portal vein of both cats. Additionally, splenorenal shunts were revealed in both cats. Follow-up computed tomographic angiography for portal vein thrombosis was performed in both cats, only one of whom received anticoagulant therapy. In the untreated cat, portal vein thrombosis had progressed with the development of an aberrant tortuous vessel. In the cat treated with low-molecular-weight heparin, the thrombus progressively decreased in size and disappeared on follow-up diagnostic imaging. Computed tomographic angiography might be useful for the diagnosis and follow-up of portal vein thrombosis in cats.