An experimental study on microcholangiographic manifestation in extrahepatic bile duct obstruction

Microcholangiographic using microbarium was done for radiological observation of the morphology of intrahepatic microbiliary system and its charge after extrahepatic bile duct obstruction. Regurgitation of microbarium into the systemic circulation was also observed. Extrahepatic bile ducts of 40 rabbits were ligated and microcholangiography was done just after ligation, after 1 day, 3 days and 5 days. Injection pressure of microbarium was 58 cm H2O in 20 rabbits and 93 cm H2O in another 20 rabbits. Histologic findings of the liver was compared with microcholangiographic findings. The results were as follows: 1. In microcholangiography, interlobular bile ducts and ductules were well noted, but bile canaliculi were not visible. 2. After extrahepatic bile duct ligation, ductules and small interlobular bile ducts were tortuously dilated and proliferated. These findings progressed according as the time after extrahepatic bile duct ligation especially between 1 and 2 days. 3. Microbarium was regurgitated into hepatic sinusoids from a portal tract due to rupture of interlobular bile ducts or ductules, and this was observed only in limited portions of sample tissue sections, but could be found in most of 40 rabbits. From the above results, the morphology of intrahepatic microbiliary system and its change after extrahepatic bile duct obstruction could be radiologically observed with microcholangiography, so this technique could be used for experimental study about the biliary system.