Circumaortic Left Renal Vein

This case report documents a circumaortic left renal vein (CLRV) observed during a routine dissection of a 65-year-old male cadaver. Two distinct renal veins were observed arising separately from the hilum of the left kidney. The first left renal vein runs transversely to the inferior vena cava (IVC), passing anterior to the aorta. This preaortic renal vein follows the path of a typical left renal vein and drains both the left testicular and suprarenal veins. The second left renal vein runs inferiorly to the IVC within the coronal plane, passing the aorta posteriorly. An in-depth literature review revealed that various anatomical anomalies of the left renal vasculature have also been observed in addition to CLRV, such as multiple renal veins (MRV) and retroaortic left renal vein (RLRV). In the case of RLRV, the left renal vein passes posterior to the aorta. In the case of CLRV, a supranumerary retroaortic left renal vein exists in addition to a typical preaortic left renal vein. While these anatomical abnormalities may go undiagnosed in healthy individuals, they do have clinical implications such as correlation with nutcracker syndrome, which can lead to hematuria. Surgical implications of CLRV also include increased risk of hemorrhage during laparoscopic nephrectomies. Awareness of anatomical variations, such as the CLRV discovered in this cadaver, hold significant clinical implications and should be considered in pre-surgical work-up for various retroperitoneal surgeries.