An unusual variation of the left renal vessels: a case report

Knowledge of the variations of renal vessels is important during operative, diagnostic and endovascular procedures in the abdomen and pelvis, and its importance has been increased because of the widespread development in renal transplantation surgeries. Taking into account of this, we observed an accessory renal artery and an accessory renal vein on the left side; the accessory renal vein forming a venous collar around the abdominal aorta. Also, we found a communicating vein connecting the accessory renal vein with gonadal vein. Left gonadal vein drained into the accessory renal vein, which drained into the inferior vena cava by passing underneath (posterior) the aorta. No such anatomical variations were found on the right side. Such unusual and complex variations must be kept in mind during radiological and surgical procedures to prevent inadvertent injury to the related structures, and also for their clinical implications.