ENDOSCOPIC ULTRASONOGRAPHY FOR DIAGNOSING CHOLEDOCHOLITHIASIS - A PROSPECTIVE COMPARATIVE-STUDY WITH ULTRASONOGRAPHY AND COMPUTED-TOMOGRAPHY

Background: We assessed the diagnostic usefulness of endoscopic ultras onography (EUS) for choledocholithiasis. Methods: A prospective series of 155 patients with suspected choledocholithiasis all underwent EUS, conventional ultrasonography, CT, and ERCP. in 142 patients with a cl ear cholangiogram on ERCP, we analyzed the capability of EUS to image the extrahepatic bile duct and to identify choledocholithiasis, compar ed with ultrasonography and CT. Results: No complications were encount ered in performing EUS. In 51 patients, ERCP demonstrated bile duct st ones, which were confirmed at endoscopic sphincterotomy or surgery. Th e extrahepatic bile duct was wholly displayed in 96% by EUS, in 60% by ultrasonography, and in 80% by CT. EUS (96%) was more sensitive than ultrasonography (63%) and CT (71%) for detecting choledocholithiasis ( p < 0.001). Although ultrasonography and CT were poorly diagnostic for choledocholithiasis in patients with small stones or those with a non dilated common bile duct, EUS was able to accurately detect choledocho lithiasis regardless of the size of stones or the diameter of the bile duct. The specificity of EUS (100%) was higher than those of ultrason ography (95%) and CT (97%). Conclusions: EUS, a safe imaging procedure , is more accurate than ultrasonography and CT and may be as accurate as ERCP for diagnosing choledocholithiasis.