For the study of the origin of cholecystitis a method was devised which allowed introduction of material into the gallbladders of experimental animals (dogs) without causing appreciable damage to the wall of the gallbladder.1 This method consisted of leading a fine rubber catheter through an incision in the common duct into the cystic duct and into the gallbladder and, after withdrawal of the catheter, restoring a fairly normal flow of bile by inserting a glass cannula into the common duct. The animals were killed after two to five days. Absence of infection and dilatation of the biliary system was noted in a large number of control animals.
In order to study the effect which long-standing cannulation might have on the biliary system, 3 of these dogs, together with 2 others, in which cholecystectomy was performed in addition to insertion of the cannula, were kept alive for a period ranging