Computed tomographic demonstration of anomalous inferior vena cava with azygos continuation.

A case of anomalous inferior vena cava with azygos continuation first diagnosed by computed tomography (CT) and later confirmed by venography is presented. In addition to identifying the dilated azygos vein in the chest, CT can determine the direction of flow in the vein by means of a bolus contrast medium injection. Once this is established, a search for the etiology of the dilated vein can be directed to the appropriate anatomic area.