"Aorta-in-Aorta" Sign on Chest Radiograph Representing Enlarged Left Superior Intercostal and Hemiazygos Veins

ABSTRACT

We recently encountered a patient with membranous obstruction of the inferior vena cava in whom the left superior intercostal and hemiazygos veins were dilated. At chest radiography, the dilation simulated the presence of a second aortic knob and descending thoracic aorta lateral to the originals, and an "aorta-in-aorta" appearance was thus created.