Large typical pulmonary arteriovenous malformation (PAVM)

Contrast-enhanced computed tomography of the chest revealed a large pulmonary arteriovenous malformation (arrow) with a large feeding artery (6 mm) and draining vein seen as parallel structures (arrowhead). This image displays many of the typical features diagnostic of PAVM including a smooth or slightly lobulated sac with well delineated borders, at least two tubular structures (ie, vessels) that seamlessly blend into the sac, the tubular structures are often parallel and larger than other vessels in the vicinity (especially for peripheral lesions), and good contrast enhancement.