RESUMO
Objective To investigate the diagnostic value of intraductal ultrasonography (IDUS) for bile duct stones by comparing between magnetic resonance cholangiopancreatography ( MRCP), endoscopic retrograde cholangiography (ERC) and IDUS. Methods ERC was performed in 30 patients with suspected extrahepatic cholelithiotic after MRCP. IDUS was applied through guide wire after ERC, and stones were removed if necessary. Results MRCP detected bile duct stones in 22 cases, misdiagnosed bile duct floc as stones in 2 and missed stones in 2 others. The accuracy, sensitivity and specificity of MRCP in diagnosis of bile duct stone were 86. 7% (26/30), 91. 7% (22/24), and 66. 7% (4/6), respectively. ERC detected bile duct stones in 23 cases, misdiagnosed bile duct air bubble as stones in 2 and missed stones in 1. The accuracy , sensitivity and specificity of MRCP in diagnosis of bile duct stone were 90% (27/30), 92% (23/25) and 66.7% (4/6) , respectively. IDUS detected 24 cases of bile duct stones, 4 bile duct floc and 2 air bubble without any misdiagnosis. The accuracy, sensitivity and specificity of IDUS in diagnosis of bile duct stone were 100%. Conclusion IDUS, safe and reliable, is superior to ERC and MRCP in diagnosis of bile duct stone.