Efficacy of full-thickness GI perforation closure with a novel over-thescope clip application device: an animal study

Background: A novel, over-the-scope clip (OTSC) system may be suitable for closure of various GI perforations. The strength and maximum diameter of closure for a single OTSC, however, are unknown. Objective: To determine the maximum closure capacity (diameter) and pressure threshold for a single OTSC. Design: Prospective ex-vivo study. Setting: Academic medical center. Method: Full-thickness, standardized defects of 5 mm, 10 mm, 15 mm, 20 mm, and 25 mm were created in porcine stomachs. Similarly, full-thickness defects of 10 mm, 20 mm, 25 mm, 30 mm, and 35 mm were created in porcine colons. A single OTSC was endoscopically deployed 5 times for each full-thickness defect size in an ex-vivo endoscopic simulator. Main Outcome Measurements: Each closure site was tested under water with compressed air for burst pressure. Results: We achieved successful closure in all stomach defects ranging from 5 to 20 mm by using 12-mm OTSCs with short teeth and colon defects ranging from 10 to 30 mm with 14-mm OTSCs with short teeth. Mean (+/- standard deviation [SD]) burst pressures for the gastric closure sites were 74.9 +/- 17.5 mm Hg for 15-mm defects, 49.3 +/- 21.6 mm Hg for 20-mm defects, and 15.2 +/- 4.1 mm Hg for 25-mm defects. Mean (+/- SD) burst pressures for the colon closure sites were 117.9 +/- 40.1 mm Hg for 20-mm defects, 57.4 +/- 4.2 mm Hg for 30-mm defects, and 10.9 +/- 7.6 mm Hg for 35-mm defects. Limitations: Ex-vivo study, does not reflect difficult locations. Conclusion: Full-thickness tissue defects ranging from 5 to 20 mm in the stomach and from 10 to 30 mm in the colon can be closed adequately with a single OTSC in an ex-vivo experimental setting. Tissue defects larger than 20 mm in the stomach and 30 mm in the colon may require more than one OTSC or supplemental endoclips to achieve adequate closure. Endoscopic inspection of the closure site does not assure adequate closure of larger perforations. (Gastrointest Endosc 2011;74:1369-75.)