Inferior vena cava duplication: demonstration by computed tomography.

Two cases demonstrating the computed tomographic (CT) appearance of inferior vena cava (IVC) duplication are presented, and the embryological, clinical, and radiological significance are discussed. Knowledge of caval anomalies can prevent misinterpretation of mediastinal masses, iliac occlusion with venous collaterals, or paravertebral lymph node enlargement. A duplicated IVC can be distinguished from para-aortic lymphadenopathy either by recognition of renal vein drainage or through intravenous contrast enhancement of the venae cavae.