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Well defined lobulated lesion appearing isodense on plain CT. The lesion is seen to have a hypodense center surrounded by multiple dilated tortuous vascular channels in the periphery of the lesion which follow similar contrast enhancement pattern as that of the portal vein in all the phases.

Hypertrophied right hepatic artery is noted which is the arterial feeder for the arteriovenous malformation. The lesion is seen to the supplied by the dilated right portal vein.

There is contrast opacification of the portal vein and its branches in the arterial phase, due to arterio-portal shunting.

These findings are characteristic for a hepatic AVM.

Ultrasound (not shown) showed a highly vascular lesion which showed multiple dilated peripheral vascular channels which showed flow pattern similar to the portal venous flow.

Gross ascites is seen.

Adrenal, kidneys, spleen and the pelvic organs appear normal.

Diffuse wall thickening with markedly thickened haustral folds is seen involving the caecum and the ascending colon.