[Morphology and significance of the left portal vein in human]

The aberrant course of a left gastric vein directly entering the liver has been reported as the left portal vein in a few cases. The authors adopted the name of 'left portal vein' for this vein and gave a brief historical summary of the left portal vein and its significance. The left gastric vein does not enter the gastropancreatic ligament from the lesser curvature, but the vein runs toward the liver alongside the hepatic ramus of vagus nerve in the hepatogastric ligament. The vein either joins the branch of the portal vein or supplies a small area of the liver after reaching the left side of the hepatic hilus. The left portal vein has already been described as the term of 'V. portae sinistra' in the bird. Many vascular vessels are found in the hepatogastric ligament. In this ligament the hepatic ramus of vagus nerve always runs toward the liver and the artery exists at a frequency of 30%. Either the left hepatic artery arising from a left gastric artery runs alongside the nerve in the ligament at a frequency of 20% or the accessory left gastric artery arising from a hepatic artery runs in a reverse direction at a frequency of 10%. Both arteries do not coexist. Moreover, the left gastric vein exits in the hepatogastric ligament in several cases and enters the liver as the left portal vein. Besides, an anastomosis of a portal vein with the renal vein rarely exists in front of the cardiac region of the ligament in cirrhosis. The aberrant left gastric vein is derived from the hepatic afferent vein through the hepatogastric ligament and exists as the left portal vein.