Endoscopic ultrasound in the evaluation of portal hypertension

Endoscopic ultrasound (EUS) can and has been used to evaluate the portal venous system in portal hypertension. Although the portal venous system cannot be imaged in its entirety, endoscopic ultrasound can be used to image various parts of the azygous vein, splenic vein, mesenteric veins, portal vein, as well as gastric varices, esophageal varices, periesophageal varices, perigastric collaterals, rectal varices and portal hypertensive gastropathy. As the technology evolves, so does our ability to image the portal venous system and its collaterals. Most of the original studies were done with standard radial EUS scopes. Less experience has been obtained with the curvelinear ultrasound scopes, which have Doppler capability for evaluation of blood flow. More recently, high frequency ultrasound probes have been used to evaluate structures in the portal venous system. In the following discussion, various anatomical regions involved by portal hypertension will be discussed using endoscopic ultrasound as an imaging modality. These regions will include gastric varices, esophageal varices, periesophageal and paraesophageal varices. EUS should be considered a complimentary imaging modality that can expand the scope of currently available imaging modalities including endoscopy.