Role of linear endoscopic ultrasound in the evaluation of hepatic veins and liver sectors

Abstract

Background and Objectives:A wide variety of imaging strategies are used to provide comprehensive preprocedural information about hepatic angioarchitecture. Currently, multidetector computed tomographic angiography and magnetic resonance angiography are complementary modalities of hepatic angioarchitecture evaluation before liver surgeries. An adequate maintenance of segmental hepatic venous drainage is also important as there is no adequate venovenous shunt between hepatic venous systems. Linear endoscopic ultrasound (EUS) can offer a detailed evaluation of hepatic veins, help in the assessment of liver segments, and can offer a possible route for EUS-guided vascular endotherapy involving hepatic veins.Methods:This article describes applied anatomy of liver lobes, sectors, and hepatic veins with techniques of imaging of hepatic veins and hepatic vein branches from four stations: abdominal part of esophagus, fundus of stomach, duodenal bulb, and descending duodenum. The imaging of hepatic veins is usually aided by proper identification of the inferior vena cava and the gallbladder. EUS of hepatic veins can help in identification of individual sectors and segments of liver. EUS offers additional superiority in assessing the flow dynamics of individual hepatic veins and also provides assessment of the anatomical features of hepatic vein length, diameter, pattern of joining, and evaluation of segmental venous drainage.Conclusions:This article describes a standard technique for visualization of hepatic veins. Knowledge of the hepatic venous territories and “venous drainage map” may provide useful information for complex liver surgeries and therapeutic procedure involving hepatic veins.