Human Anatomy, Part 2 - K. A. Diubenko, A. K. Kolomiitsev, Yu. B. Chaikovsky 2008

Special Part
Cardiovascular System, systema cardiovasculare – Venous System
Veins of the Systemic Circulation – Inferior Vena Cava System – Hepatic Portal Vein

The portal vein of the Liver, v.portae hepatica (Fig. 74), is a short trunk 6–8 cm long and 15–20 mm in diameter, running within the hepatoduodenal ligament, lig.hepatoduodenale. It is formed by the confluence of three Veins: the superior mesenteric, inferior mesenteric, and splenic**. The portal vein and its tributaries constitute the portal Venous system. The HEPATIC PORTAL VEIN drains Blood from the unpaired Organs of the Abdominal cavity (Stomach, large and small intestines, Spleen, Pancreas).

Passing within the lig.hepatoduodenale posterior to the hepatic artery and Bile duct, the hepatic portal vein enters the porta hepatis, where it divides into right and left branches. The right and left hepatic branches branch into segmental veins and then transition into interlobular veins. Within the hepatic lobules, they terminate in sinusoidal capillaries that drain into the central vein. The latter serve as the initial vessels for the hepatic veins, which empty into the INFERIOR VENA CAVA.

Thus, venous blood from the Internal Organs of the abdominal cavity is detoxified from harmful substances in the liver before entering the inferior vena cava.

Class="center">

Fig. 74. Portal vein of the liver, v.portae hepatis and its tributaries (diagram)

Tributaries of the hepatic portal vein:

1. Superior mesenteric vein, v.mesenterica superior (Fig. 74), located in the mesentery of the Small Intestine alongside the superior mesenteric artery. The following tributaries empty into its trunk: a) VEINS OF THE small intestine (vv.jejunales et ilei); b) veins of the cecum and Appendix (vv.ileocolicae); c) veins of the ascending colon (v.colica dextra); d) veins of the transverse colon (v.colica media); e) veins of the HEAD of the pancreas and duodenum (vv.pancreaticoduodenales superior et inferior); f) veins of the greater curvature of The Stomach (v.gastroepiploica dextra).

2. Splenic vein, v.lienalis (Fig. 74), located inferior to the splenic artery and posterior to the pancreas. It is formed by the confluence of pancreatic veins, vv.pancreaticae, the left gastro-omental vein, v.gastroepiploica sinistra, and short gastric veins, vv.gastricae breves. The splenic vein drains blood from the spleen, the greater part of the stomach (v.gastroepiploica sinistra, vv.gastricae breves), and the pancreas (vv.pancreaticae).

3. Inferior mesenteric vein, v.mesenterica inferior (Fig. 74), located retroperitoneally, posterior to the head of the pancreas. It is formed by the confluence of the left colic vein, v.colica sinistra, sigmoid veins, vv.sigmoideae, and superior rectal vein, v.rectalis superior. Its trunk empties into the superior mesenteric vein, or occasionally into the splenic vein. The inferior mesenteric vein drains blood from the rectum (upper part), sigmoid colon, and descending colon.

In addition to the three aforementioned tributaries, A number of smaller tributaries empty into the hepatic portal vein: the cystic vein, v.cystica, right and left gastric veins, vv.gastricae dextra et sinistra, prepyloric vein, v.prepylorica, and paraumbilical veins, vv.paraumbilicales, located within the lig.teres hepatis.