background: The early detection of liver metastases in patients with gastric carcinoma is important for determining the appropriate therapy; however conventional imaging techniques are limited for detecting occult liver metastases. Previous studies have shown that the measurement of the Doppler perfusion index (DPI)--ratio of hepatic arterial to total liver blood flow--can detect the presence of even small hepatic tumors. In this study, we compared the measurement of DPI with computed tomography (CT) for detecting gastric liver metastases.methods: At presentation, 43 patients with gastric carcinoma underwent CT scanning of the liver and after 12 hours of fasting, DPI measurement was carried out using Doppler sonography.results: Both techniques detected overt liver metastases in 9 of the 43 patients. Of the 34 remaining patients with an apparently disease-free liver on the basis of CT, laparatomy, or laparoscopy, 14 subsequently develop liver metastases over a follow-up period of 4 years, 13 of which had been predicted by DPI at the time of presentation.conclusion: The data suggest that the measurement of the DPI is more sensitive than a CT scan for detecting liver metastases secondary to gastric carcinoma.