A novel postgraduate endoscopic course using a large animal model of secondary Crohn's disease stricture.

BACKGROUND: The increasing complexity of advanced endoscopic techniques places a high demand on the endoscopist's expertise. Thus, live porcine models have been more frequently used for training. We briefly describe a hands-on postgraduate endoscopic course regarding a novel method of treatment of anastomotic strictures in a porcine model. METHODS: The porcine model of Crohn's disease anastomotic stricture with two artificial side-to-side ileo-colonic anastomoses was used. Participants performed endoscopic stricturotomy under supervision at one of two equipped endoscopic stations. Available animals were endoscopically re-examined 3 months after the course. RESULTS: Twelve anastomoses were prepared for the course. Eleven circumferential stricturotomies together with horizontal cut and clip placement were conducted. All anastomoses were passable for the scope after the procedure, and no case of perforation or bleeding occurred. All anastomoses available for re-examination remained passable for the endoscope after 3 months. CONCLUSION: We successfully organised the first endoscopic hands-on course for the training of endoscopic stricturotomy on a large animal model.

Novel porcine model of Crohn's disease anastomotic stricture suitable for evaluation and training of advanced endoscopic techniques.

BACKGROUND AND AIMS: Currently, treatment options in postsurgical recurrence of stricturing Crohn's disease (CD) are limited. However, development of new invasive endoscopic techniques in clinical practice has safety constraints. The aim of this study was to create a large animal model of anastomotic stricture with CD properties to enable development of new techniques and training. METHODS: A side-to-side ileocolonic anastomosis was created in a modified Roux-en-Y manner with bowel continuity preserved. Two weeks after surgery, we began endoscopic submucosal injections of phenol/trinitrobenzenesulfonic acid solution. This solution was injected every 2 weeks in each quadrant of the anastomosis until development of a stricture. The anastomosis site was assessed endoscopically 2 weeks after the last application (baseline) and then every 2 months until month 6. Endoscopically nonpassable strictures were treated with balloon dilation, endoscopic stricturotomy, and stent placement to confirm the feasibility of such interventions. RESULTS: Nineteen minipigs were included with no postoperative adverse events. After a mean of 4.4 ± .7 injection sessions with 10.5 ± 3.0 mL of the solution, anastomotic strictures were created in 16 pigs (84.2%). Mean diameter of the strictures at baseline was 11.6 ± 2.2 mm. The strictures were inflamed, and the endoscope could not pass. Follow-up was successfully completed in 15 animals (79.0%) with the mean deviation from the initial diameter in every measurement of -.02 ± 2.26 mm (P = .963) and a mean final diameter of 11.7 ± 3.4 mm. The histopathologic evaluation revealed the presence of submucosal fibrosis, chronic inflammation, and microgranulomas. All strictures were amenable to endoscopic therapeutic interventions. CONCLUSIONS: We developed a novel, reproducible porcine model of anastomotic stricture with histologically verified changes mimicking CD and stable diameter for more than 6 months. It is suitable for further endoscopic interventions.