RESUMO
E.S.T. is performed not only for the treatment but also for the diagnosis of biliary tract diseases. E.S.T. serves as a diagnostic aid for some of biliary tract diseases which require such procedures as a peroral cholangioscopy or biopsy of the biliary duct for precise diagnosis and further differential diagnosis. The diseases of our patients were diagnosed by clinical findings and such diagnostic maneuvers as abdominal ultrasonography, intravenous cholangiography, percutaneous transhepatic chorangiography(P.T.C.), endoscopic retrograde chorangiopancreatography(E.R.C.P.), In all the two cases, abdominal ultrasonography revealed dilated extrahepatic duct, but biliary trees were not visualized at E.R.C.P. In one of the two cases, P.T.C. revealed a filling defect with dilated common bile ducts(CBD) but we could not make a differential diagnosis of CBD stone from CBD cancer. In another of the two cases, on which intravenous cholangiography was done, we could not see CBD. For the purpuse of precise diagnosis and further differential diagnosis, we performed EST and then ERCP thraugh widened papillae. With those procedures, CBD stones were shown.