Idiopathic accessory hemiazygos vein aneurysm with an incidental mediastinal mass

Abstract

We herein report the case of an idiopathic aneurysm of the accessory hemiazygos vein diagnosed by contrast-enhanced computed tomography (CT) and angiography. The patient was asymptomatic, and a posterior mediastinal mass was incidentally found on CT. Because endoscopic ultrasonography showed no thrombus formation in the aneurysm, the patient was therefore managed conservatively. © 2012 The Japanese Society of Internal Medicine.