Clinical Application of Ultrasonography in Diagnosis of Biliary Tract Stone

For evaluating the effectiveness of ultrasonography (US) in diagnosis of biliary tract stone, 363 patients of benign biliary tract disease were examined by US before surgery. The diagnostic sensitivity, specificity and accuracy of US in intrahepatic stone were 95.6%, 98.2% and 97.5% respectively. The diagnostic sensitivity, specificity and accuracy of US in common bile duct stone were 64.9%, 93.9% and 82.1% respectively. The diagnostic sensitivity, specificity and accuracy of US in gallbladder stone were 94.9%, 95.7% and 95.3% respectively. Our study confirmed that the ultrasonographic diagnosis of intrahepatic stone and gallbladder stone is very effective and reliable. It is also useful in diagnosis of common bile duct stone. Ultrasonography is the ideal modality to be applied as a screen test for biliary tract stone, especially in Taiwan where intrahepatic stone is prevalent.