Intra-arterial CT angiography visualization of arterial supply to inferior vena cava tumor thrombus prior to radioembolization of hepatocellular carcinoma.

Unresectable hepatocellular carcinoma has a high frequency of vascular invasion and arterial parasitization. Trans-arterial radioembolization using yttrium-90 (Y90) microspheres is a possible treatment option. Paramount to its success is the meticulous angiographic interrogation of tumor feeding arteries and extra-hepatic supply. We describe a patient with tumor invasion of the inferior vena cava with arterial supply from the right inferior phrenic artery, which was exquisitely visualized using intra-arterial computed tomographic angiography (IACTA) during the planning technetium-99m macro aggregated albumin phase. This technique was useful in planning which artery to administer Y90 microspheres into for maximal brachytherapy. Although patient outcome was poor due to significant arterio-portal shunting, we believe that IACTA is a useful adjunct to conventional digital subtraction angiography in planning radioembolization therapy.