The venous drainage of the adrenal (suprarenal) glands is typically comprised of a single vein draining each adrenal gland. Like the gonadal veins each side drains differently:
- left suprarenal vein drains into the left renal vein .
- right suprarenal vein drains directly into the inferior vena cava .
Variant anatomy of the suprarenal vasculature is common and has been reported in 13% of patients .
On the right side, the variants include one central vein with multiple significant accessory veins or a suprarenal vein that drains directly into the hepatic vein . On the left side, variants include two significant adrenal veins or a branch to the left inferior phrenic vein .
Variation is more common on the right side than on the left (17% vs. 9%) .