Producing experimental cholangiectasis in dogs by the stripping method.

Despite the general belief that cholangiectasis is caused by biliary stenosis, clinical cases of cholangiectasis exist which do not seem to have biliary stenosis. The purpose of this research was to produce cholangiectasis models without stenosis, and it was found that stripping the surrounding supportive tissues from the extrahepatic bile duct resulted in cholangiectasis without biliary stenosis. The maximum diameter and intraluminal pressure of the bile duct were specifically examined in 24 mongrel dogs before and 4 weeks after stripping. The mean diameter of the bile duct was 2.44 mm before stripping but 6.47 mm 4 weeks after stripping, the latter being significantly larger than the former (p less than 0.001). There were no significant differences in biliary passage according to cholangiomanometry performed before and after stripping, which indicated an absence of biliary stenosis. Histological examination of the bile duct wall and duodenal papilla after stripping showed only mild inflammatory changes. These models could thus be used for the analysis of cholangiectasis without biliary stenosis. Moreover, these models clinically suggest that there are cases of cholangiectasis without biliary stenosis and that sphincteroplasty or choledochojejunostomy should not be applied blindly. In other words, these techniques should only be applied when biliary stenosis has been observed after careful examination.