The present study deals with the value of CDS in liver transplantation. Between September 1988 and October 1991 CDS of hepatic vessels was carried out in 194 liver transplants. Flow direction and flow velocity in the portal vein could be demonstrated in 97%. Measurement of flow velocity indicates the extent of portal hypertension; this can be confirmed by determining flow direction in the splenic and superior mesenteric veins. In 47 of 179 patients venous collaterals were demonstrated and in 15 of 179 patients there was retrograde flow in the splenic vein. In 95% of patients CDS indicated flow direction in the hepatic artery and in 93% in the hepatic veins. Thrombosis of liver vessels (portal and hepatic veins) was demonstrated in 11 out of 13 patients by means of CDS.