- May be congenital or posttraumatic (liver biopsy, liver transplant)
- Variably sized, multilobulated, and multicystic appearing mass in the liver
- Enlarged feeding artery with high-velocity and low-resistance flow, arterial flow within the lesion, and reversal of flow and arterialization of the draining portal vein
- Can be seen with hereditary hemorrhagic telangiectasia where tiny arterioportal fistulas form