Endoscopic ultrasonography - emerging applications in hepatology

Abstract

The inspection of the liver is a valuable part of the upper endoscopic ultrasonography (EUS) studies, regardless of the primary indication for the examination. The detailed images of the liver segments provided by EUS allows the use of this technique in the study of parenchymal liver disease and even in the diagnosis and classification of focal liver lesions. EUS has also emerged as an important tool in understanding the complex collateral circulation in patients with portal hypertension and their clinical and prognostic value. Recently, EUS-guided portal vein catheterization has been performed for direct portal pressure measurement as an alternative method to evaluate portal hemodynamics. In this review, the authors summarize the available evidence regarding the application of EUS to patients with liver diseases and how we can apply it in our current clinical practice.

Keywords: Endoscopic ultrasonography; Focal liver lesions; Gastroesophageal varices; Liver biopsy; Portal hypertension.

Figure 1

Endoscopic ultrasonography images of the hepatic structures from the proximal stomach: The left lateral segments (S2 and S3) (A); S1 (caudate lobe) and segment 4 (S4) (B); S1 with portal vein behind it (C); Umbilical part of the left portal vein (D). Images recorded using the curved linear scanning echoendoscope (GF-UCT 180; Olympus Medical Systems, Tokyo, Japan) coupled with a ProSound Alpha 10 processor (Aloka, Tokyo, Japan). LHV: Left hepatic vein; MHV: Middle hepatic vein; LPV: Left portal vein; LT: Ligamentum teres.

Figure 2

Esophageal collateral vessels (arrow) (A), esophageal varices seen as hypoechoic structures inside the esophageal wall (arrows) (B); and paraesophageal varices and perforating veins (C). Images recorded using the radial scanning echoendoscope (GF-UE160-AL5; Olympus Medical Systems, Tokyo, Japan) coupled with a ProSound Alpha 10 processor (Aloka, Tokyo, Japan).