CT evaluation of anomalies of the inferior vena cava and left renal vein.

Two patients with duplication of the inferior vena cava and two patients with a retroaortic left renal vein were examined by computed tomography (CT). The characteristic CT appearance of these two entities, as well as circumaortic left renal vein and transposition of the inferior vena cava, is discussed. A scheme by which these anomalies of the inferior vena cava and left renal vein may be distinguished from one another and from pathologic entities such as lymphadenopathy and a dilated gonadal vein is reported.