Short-term endobiliary stenting results in chronic inflammation of the porcine extrahepatic biliary system

This study reports the histologic changes seen in the biliary ductal system and pancreas as a result of endobiliary stenting. Ten mini pigs underwent endoscopic placement of suprapapillary endobiliary stents. The animals were killed and the liver, biliary tree, and pancreas were resected en bloc and prepared for histologic examination. Endobiliary stenting was found to res ult in significant chronic inflammation in the biliary system within 4 week s of stent placement. These changes were present throughout the entire extr ahepatic biliary ductal system and persisted throughout the 15-week study p eriod. There was no significant acute inflammation in the biliary tree nor acute or chronic inflammation in the pancreatic duct. Further study is indi cated to determine whether these changes will result in fibrosis and strict ure.