A case of extrahepatic portal vein aneurysm accompanying lupoid hepatitis.

Portal vein aneurysm, especially that of the extrahepatic portal vein, is a very rare entity. We recently observed a case of aneurysm at the junction of the superior mesenteric vein and the splenic vein which accompanied lupoid hepatitis. Abdominal ultrasonography, color Doppler ultrasonography, abdominal computed tomography (CT), magnetic resonance imaging (MRI), and angiography revealed a portal vein aneurysm that increased in size after a period of about 10 months.