Sonographic evaluation of patients with portal hypertension.

The availability of real-time sonography has facilitated its use in the assessment of patients suspected of portal hypertension. Dilatation of the portal venous system may occur in portal hypertension, and a portal vein diameter greater than 13 mm is indicative of portal hypertension with a sensitivity of about 50%. Sonographic demonstration of lack of caliber variation of the portal system has a sensitivity of about 80%. The presence of venous collaterals can be demonstrated in about 90% of patients suitable for sonography. The coronary gastroesophageal varices can be seen in 90% when they are large sized, and in 65% when they are small sized. Other collaterals such as umbilical vein, duodenal varices, and gastrorenal and splenorenal varices can be detected. Sonography is a valuable screening procedure in the evaluation of portal hypertension and provides valuable information regarding the size and morphology of the liver and spleen, caliber and patency of the portal venous system, and the existence and location of the varices.