1 — Hepatic portal vein; 2 — Splenic vein; 3 — Left colic vein; 4 — Inferior mesenteric vein; 5 — Sigmoid veins; 6 — Superior rectal vein
1 — Hepatic portal vein; 2 — Splenic vein; 3 — Left colic vein; 4 — Inferior mesenteric vein; 5 — Sigmoid veins; 6 — Superior rectal vein