Digestive disorders

I./1.3.: Lymphtic drainage of the liver

Approximately 25-50% of the lymph in the thoracic duct comes from the liver. A superficial and a deep lymphatic network collect the hepatic lymph.

From the deep lymphatic system the lymph may travel along the hepatic veins, through the caval hiatus, toward the primary regional lymph nodes named right lateral phrenic nodes (sublobular path). Another way for the lymph flow is, along the portal vein branches, toward the lymph nodes of the liver hilum (portal path). According to the investigations, the 80% of the hepatic lymph is drained through the hilar lymphatic vessels.

The superficial lymphatic network is formed within the Glisson’s capsule. The anterior surface of the liver is drained through the falciform ligament and the bare area, toward the anterior phrenic nodes (capsular path). Lymph vessels from these nodes join the parasternal nodes along the internal thoracic artery as well as the bronchomediastinal nodes. The lymph from the left and right superior areas drains through the triangular ligaments to the diaphragm, then toward the pancreatolienal nodes. Lymph vessels running in the coronary ligaments enter the nodes situated around the terminal part of the inferior vena cava. From the postero-inferior surface of the liver, the lymph travels mostly toward the hilar nodes.

The primary regional lymph nodes form groups around hilar structures such as the cystic duct and the proper hepatic artery (cystic node, hilar and hepatic artery node). Lymph nodes of the hepatic pedicle form groups in the hepatoduodenal ligament, along the proper hepatic artery (ventral group), along the common hepatic duct, and the on the cystic duct (dorsal group), beteween the two layers of the lesser omentum, in the porta hepatis and around the neck of the gallbladder.

Further pathway from the primary nodes conducts to the peripancreatic, paracardiac and celiac nodes. The celiac nodes form three groups: gastric nodes, pancreatolienal nodes and hepatic nodes.

Data on the drainage of the gallbladder indicate that the lymph from it travels toward the nodes around the cystic duct and the common bile duct then the lymph vessels reach the posterosuperior pancreaticoduodenal or the retroportal nodes. The efferent vessels from these nodes run to nodes located around the superior mesenteric artery and the celiac trunk (mesnteric and celiac nodes), then the vessels reach the interaortocaval nodes.

Few data are available on lymphatic vessels that run in the free edge of the falciform ligament, along the round ligament of the liver, connecting the hepatic capsular lymphatic network with the lymphatic vessels of the periumbilical abdominal wall, and those running along the arteries traversing this region (superficial epigastric and inferior epigastric arteries). Through the small paraumbilical veins travelling next to the round ligament, the hematogenous dissemination of cancer cells may occur.