Diagnosis by ultrasonography and isotopic phlebography of a malformation of the inferior vena cava: proximal transposition with anterior crossing over the aorta.

A case of a previously undescribed malformation of the inferior vena cava is reported: there was distal normoposition and proximal transposition, with anterior crossing over the aorta; the right renal vein flowed into the inferior vena cava located on the left, after crossing over the anterior face of the aorta. This anomaly was shown by echography and isotopic phlebography.