An unusual course of the right renal artery associated with an anomalous inferior vena cava

In a 55-year-old male cadaver, the inferior vena cava bifurcated at a level midway between the hilus and inferior pole of the right kidney. The narrow er branch, on the right side, drained the right renal and hepatic veins, as cended as the normal inferior vena cava, passed through the caval opening o f the diaphragm and drained into the right atrium. The wider branch on the left side drained the left renal vein and penetrated the right crus of the diaphragm as the azygos vein. This vein ascended in the posterior mediastin um and drained into the superior vena cava. The hemiazygos and accessory he miazygos veins were absent. In addition to these anomalies, the right renal artery entered the hilus after coursing through the above-mentioned two br anches at the bifurcation. No congenital anomalies of the heart or abdomina l viscera and main arteries were seen.