DUPLEX ULTRASOUND OF HEPATIC AND PORTAL VEINS

Duplex ultrasound allows direct access to portal venous and hepatic ve in hemodynamics. This method has been accepted as a reliable procedure to detect portal and splenic venous thrombosis, Budd-Chiari's syndrom e, portosystemic collateralisation and changes in the portal venous bl ood flow direction with a high rate of sensitivity. Besides these qual itative findings Doppler flowmetry allows quantitative measurement of portal venous blood flow velocities. The estimation of portal hyperten sion and the prediction of the risk of variceal bleeding by quantitati ve Doppler flowmetry is of increasing clinical importance. In monitori ng the efficiency of medicational prophylaxis against gastrointestinal bleeding is also helpful. Duplex ultrasound can be used to evaluate t he function of portocaval shunts including the intrahepatic stent shun t as well as to detect vascular complications after liver transplantat ion. Furthermore the method is gaining importance in the diagnosis and monitoring of therapy of acute liver transplant rejection.In case of liver tumors duplex ultrasound is of value for tumor staging and provi des information about the dignity on the basis of perfusion patterns.