Anomalous inferior vena cava with accessory hemiazygos continuation.

A case of accessory hemiazygos continuation of an anomalous left inferior cava with drainage via the highest intercostal vein into the left brachiocephalic vein is reported and the embryologic and radiological significance discussed. The diagnosis is suggested on plain films by the dilated highest intercostal vein, the so-called aortic nipple, and a widened left paraspinal line.