The retroaortic left renal vein (RLRV) has four subtypes:
- RLRV joining the IVC in the normal position.
- RLRV joining the IVC at the level of L4–5.
- Circumaortic or collar left renal vein, having two limbs crossing anterior and behind the aorta.
- RLRV drains into the left common iliac vein.
The most common urological symptom attributed to the abnormal course of the left renal vein is hematuria.