Ultrasonic evaluation of portacaval shunts.

Patients who had portacaval shunts were examined both before and after surgery. In the majority of cases, it was possible to detect the portcaval shunt by actually demonstrating the site of anastomosis. There was dilatation of the vena cava just cephalad to the site of the anastomosis due to the increased volume of blood entering the vena from the portal system. Mesocaval shunts have also been detected. Splenorenal shunts, however, could not be demonstrated in this series. While gray scale B scan ultrasound was used to record the site of anastomosis and measure the vessel diameters, real time two-dimensional ultrasound provided dynamic information. Long term serial examination are being obtained to evaluate the continued patency of the shunts. Ultrasound appears to be a promising new noninvasive study for the evaluation of portcaval shunts.