NEW METHOD: Experimental Endoscopy Endoluminal clip closure of a circular full-thickness colon resection in a porcine model (with videos) Gottumukkala S. Raju, MD, FRCP (UK), FACP, FACG, Ijaz Ahmed, MD, Goro Shibukawa, MD, Allison Poussard, BS, Douglas Brining, DVM Galveston, Texas, USA Background: Linear perforations of the colon can be closed by the application of clips through a colonoscope. It is unclear whether circular perforations after full-thickness resection of the colon can be closed with clips. Objective: To develop an animal model for circular perforation of the colon and to study different techniques to accomplish a leakproof sealing of the circular perforation of the colon. Design: Pilot study. Setting: University medical center. Animals: Ten pigs: 2 perforations in the 1st pig and 1 perforation in the 2nd to 9th pigs were closed with clips. In the 10th pig, 5 perforations were created, and the dimensions of the perforation were measured. Interventions: Creation of a circular full-thickness resection of the colon with a band-ligation–resection device, followed by longitudinal or transverse endoluminal closure of the perforation by using the first clip opened and applied in the 3- to 9-o’clock or the 6- to 12-o’clock direction in relation to the circular perforation, respectively. Main Outcome Measurements: The mean (standard deviation) size of circular perforation was 1.7 Æ 0.075 cm (range, 1.5–2.0 cm). Necropsy immediately after closure of the perforation was done to examine the closure and to confirm the quality of sealing with the methylene blue dye leak test. Results: The transverse closure was unsuccessful in the closure of 3 perforations, whereas the longitudinal clo- sure resulted in a leakproof sealing in 6 of the 7 closures. Limitations: Perforation of the adjacent viscera limits it to a nonsurvival study. Conclusions: Endoluminal application of clips by using the longitudinal closure technique results in a leak proof sealing of circular perforations of the colon. Despite significant advances in the endoscopic manage- ment of various complications of colonoscopic therapy (eg, bleeding), colon perforation, continues to plague both the endoscopist and the patient alike, because of the need for surgery and the risk of mortality associated with it. 1,2 Perforations after diagnostic colonoscopy are generally linear lacerations, whereas those developing after snare polypectomy tend to be nonlinear (or circular). 3 During the last decade, clips were used to manage a variety of esoph- ageal, gastric, and colonic perforations; fistulas; and leaks. 4,5 Clinical experience with the endoscopic closure of colon perforations with clips is limited to a couple of case reports. 6,7 Preliminary laboratory experience with the endo- luminal closure of small linear perforations of the colon is encouraging. 8 Subsequently, we demonstrated that a leak- proof sealing could be achieved immediately after endolumi- nal closure with clips of a long (5-7 cm) linear perforation of the colon. 9 Encouraged by these results, we wondered whether circular (nonlinear) perforations after a full-thick- ness resection of the colon could be closed as well. To study endoluminal closure of a full-thickness circular resection of the colon, we developed an animal model by snare resection of a band-ligated segment of the colon. Our goal was to evaluate whether a leakproof sealing of circular colon perforation could be created immediately after colonoscopic clip closure of circular perforations of the colon and also to find out the best method of closure to achieve this goal. Copyright ª 2007 by the American Society for Gastrointestinal Endoscopy 0016-5107/$32.00 doi:10.1016/j.gie.2006.06.085 www.giejournal.org Volume 65, No. 3 : 2007 GASTROINTESTINAL ENDOSCOPY 503