Percutaneous Transcholecystic Approach for an Experiement of Biliary Stent Placement: An Experimental Study in Dogs

ABSTRACT

PURPOSE: To determine, in an experimental study of biliary stent placement, the usefulness and safety of the percutaneous transcholecystic approach and the patency of a newly designed biliary stent. MATERIALS AND METHODS: A stent made of 0.15-mm-thick nitinol wire, and 10 mm in diameter and 2 cm in length, was loaded in an introducer with an 8-F outer diameter. The gallbladders of seven mongrel dogs were punctured with a 16-G angiocath needle under sonographic guidance, and cholangiography was performed. After anchoring the anterior wall of the gallbladder to the abdominal wall using a T-fastener, the gallbladder body was punctured again under fluoroscopic guidance. The cystic and common bile ducts were selected using a 0.035-inch guide wire and a cobra catheter, and the stent was placed in the common bile duct. Post-stenting cholangiography was undertaken, and an 8.5-F drainage tube was inserted in the gallbladder. Two dogs were followed-up and sacrificed at 2, 4, and 8 weeks after stent placement, respectively, and the other expired 2 days after stent placement. Follow-up cholangiograms were obtained before aninmal was sacrificed, and a pathologic examination was performed. RESULTS: Stent placement was technically successful in all cases. One dog expired 2 days after placement because of bile peritonitis due to migration of the drainage tube into the peritoneal cavity, but the other six remained healthy during the follow-up period. Cholangiography performed before the sacrifice of each dog showed that the stents were patent. Pathologic examination revealed the proliferation of granulation tissue at 2 weeks, and complete endothelialization over the stents by granulation tissue at 8 weeks. CONCLUSION: Percutaneous transcholecystic biliary stent placement appears to be safe, easy and useful. After placement, the stent was patent during the follow-up period.