title: Enlargement of the posterior turn of the azygos arch simulating a mediastinal mass.
abstract: A round mass in the dorsal, upper-right mediastinum is demonstrated in a patient with aneurysm of the innominate artery. Selective azygography reveals enlargement of the posterior turn of the azygos arch.
mesh_terms: D001401:Azygos Vein / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008479:Mediastinal Neoplasms / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011859:Radiography