Anatomy of the Portal Vein Bifurcation: Implication forTransjugular Intrahepatic Portal Systemic Shunts

Purpose: The relationship of the portalvein bifurcation to the liver capsule in Asians, which is an importantlandmark for transjugular intrahepatic portosystemic shunt, has notpreviously been described. Methods: The anatomy of theportal vein bifurcation was studied in 70 adult Chinese cadavers; itwas characterized as intrahepatic or extrahepatic. The length of theexposed portion of the right and left portal veins was measured whenthe bifurcation was extrahepatic. Results: The portalvein bifurcation was intrahepatic in 37 cadavers (53%) andextrahepatic in 33 cadavers (47%). The mean length of the right andleft extrahepatic portal veins was 0.96 cm and 0.85 cm respectively.Both were less than or equal to 2 cm in 94% of the cadavers withextrahepatic bifurcation. There was no correlation between the presenceof cirrhosis and the location of the portal vein bifurcation(p = 1.0). There was no statisticallysignificant difference in liver mass in cadavers with eitherextrahepatic or intrahepatic bifurcation (p =0.40). Conclusions: These findings suggest that fortransjugular intrahepatic portosystemic shunt placement, a portal veinpuncture 2 cm from the bifurcation will be safe in most cases.