A pilot proof-of-concept study of a modified device for one-step endoscopic ultrasound-guided biliary drainage in a new experimental biliary dilatation animal model

AIM: To evaluate the technical feasibility of a modified tapered metal tip and low profile introducer for one-step endoscopic ultrasound (EUS)-guided biliary drainage (EUS-BD) in a new experimental biliary dilatation porcine model. METHODS: A novel dedicated device for one-step EUS-guided biliary drainage system (DEUS) introducer has size 3F tapered catheter with size 4F metal tip for simple puncture of the intestinal wall and liver parenchyma without graded dilation. A self-expandable metal stent, consisting of both uncovered and nitinol-covered portions, was preloaded into DEUS introducer. After establishment of a biliary dilatation model using endoscopic hemoclips or band ligation with argon plasma coagulation in 9 mini-pigs, EUS-BD using a DEUS was performed following 19-G needle puncture without the use of fistula dilation devices. RESULTS: One-step EUS-BD was technically successful in seven pigs [7/9 (77.8%) as intention to treat] without the aid of devices for fistula dilation from the high body of stomach or far distal esophagus to the intrahepatic (n = 2) or common hepatic (n = 5) duct. Primary technical failure occurred in two cases that did not show adequate biliary dilatation. In seven pigs with a successful bile duct dilatation, the technical success rate was 100% (7/7 as per protocol). Median procedure time from confirmation of the dilated bile duct to successful placement of a metallic stent was 10 min (IQR; 8.9-18.1). There were no immediate procedure-related complications. CONCLUSION: Modified tapered metal tip and low profile introducer may be technically feasible for one-step EUS-BD in experimental porcine model. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.