P-HPB-15: Techniques of Linear Endoscopic Ultrasound in the Evaluation of Portal Vein Branches

The main portal vein bifurcation occurs near the liver hilum. Both the branches travel in the transverse fissure of liver. The bifurcation lies in an imaginary transverse plane in the transverse fissure, in which the left portal vein is at a higher level than the right portal vein and the left portal vein has a longer extrahepatic course (~2/3(rd) of transverse fissure) as compared to the right portal vein (~1/3(rd) of transverse fissure). The right portal vein divides into two branches after entering the liver. The imaging of portal vein branches can be done from three stations: abdominal part of esophagus and stomach, duodenal bulb, and descending duodenum. The imaging of portal vein branches is significantly aided by following the fissures of liver. The imaging from stomach keeps the focus of imaging around the left sagittal fissure, where the left portal vein is present; the imaging from duodenal bulb keeps the focus of imaging around the transverse fissure, where the main portal vein is present; and the imaging from descending duodenum keeps the focus of imaging around the right sagittal fissure, where the right portal vein is present. Following the fissure from one part to other is possible by clockwise and counterclockwise rotation and allows the imaging of different parts of portal vein. The imaging from the abdominal part of esophagus and stomach is the most convenient station of imaging for most operators.