Incidence and clinical significance of spontaneous intrahepatic portosystemic venous shunts detected by sonography in adults without potential cause

PURPOSE: B-mode and color Doppler sonography were used to assess the incidence and clinical significance of spontaneous intrahepatic portosystemic venous shunt in adults without detectable cause. METHODS: A total of 25,579 adults without potential cause of intrahepatic portosystemic venous shunt were screened using B-mode sonography. Suspicion of shunt was confirmed by color Doppler sonography. Patients with shunt were followed up with sonography at 6- to 12-month intervals and received dietary education to prevent the ingestion of extra-large amounts of protein. During each sonography session, the patients were asked to report any experience of consciousness disturbance. RESULTS: Six patients (0.0235%) showed evidence of shunt on color Doppler sonography. Direct communication between a right portal branch and the inferior vena cava was found in 3 patients; a small aneurysm connecting a peripheral portal branch to the hepatic vein was found in the remaining 3 patients. Five patients were followed up (range, 12-60 months) and showed no change in the size of the shunt. None of the patients with shunt reported an experience of consciousness disturbance. CONCLUSIONS: The incidence of spontaneous intrahepatic portosystemic venous shunt is extremely low in asymptomatic adult patients. Follow-up and dietary control seen to be suitable for their management.