Renal vein ligation in absence of vena caval obstruction.

This is a report of a patient whose left renal vein was ligated in the course of a right nephrectomy for a large Wilms tumor, in the presence of an unobstructed vena cava and without established venous collateral circulation. It would appear that even with sudden obstruction to venous outflow the left kidney can develop an adequate network of collateral venous drainage capable of supporting normal renal function.