We studied the direction of blood flow in the splenic vein, using a combined ultrasonic system consisting of an electronic sector scanner and a pulsed Doppler flowmeter, in 21 patients with a large spontaneous splenorenal shunt demonstrated by angiography. Pulsed Doppler flowmetry revealed hepatofugal flow in the splenic vein in all 11 patients with chronic spontaneous hepatic encephalopathy, and hepatopetal flow in 10 patients without encephalopathy. In the former, hepatofugal flow of part of the superior mesenteric venous blood into the splenorenal shunt was corroborated by the venogram obtained after superior mesenteric arteriography. In 5 patients without a history of hepatic encephalopathy, superior mesenteric arteriography demonstrated hepatofugal flow of part of the superior mesenteric venous blood into the splenorenal shunt. Pulsed Doppler flowmetry, however, revealed hepatopetal flow in all of these patients, suggesting that the angiographic finding of hepatofugal flow may have represented an artifact.