title: An innovative ex-vivo porcine upper gastrointestinal model for submucosal tunnelling endoscopic resection (STER).
abstract: Background and study aims:Submucosal tunnelling endoscopic resection (STER) is a novel endoscopic technique to remove submucosal tumour (SMT). We propose a novel, low cost simulator for training of techniques for STER.Patients and methods:The model consisted of an ex-planted porcine oesophagus, stomach and duodenum with marbles embedded surgically in the submucosal plane. Two expert endoscopists with experience in submucosal tunnelling and 5 board-certified endoscopists with no experience in submucosal tunnelling were recruited. Participants were asked to perform a diagnostic endoscopy and 2 STER procedures, 1 in the oesophagus and 1 in the stomach. They also answered a structured questionnaire. Factors including operative time, mucosal and muscular injury rate, injection volume and accuracy of endoscopic closure were assessed.Results:The median time for localization of all SMTs was 40.1 seconds for experts and 38.5 seconds for novices (P= 1.000). For esophageal STER, the length of mucosal incisions and tunnelling distances were comparable between the 2 groups. The median volume injected by the novice group was significantly lower than the experts (15 mL vs 42.5 mL (P= 0.05). The median tunnelling time per length was 25.9 seconds/mm for the experts and 40.8 seconds/mm for the novice group (P= 0.38). There was a higher rate of mucosal injury and muscular perforation in the novice group (8 vs 0;P= 0.05). For gastric STER, the length of mucosal incisions and tunnel distances were comparable between the 2 groups. The median tunnelling time per length for the experts was 23.3 seconds/mm and 34.6 seconds/mm for the novice group (P= 0.38). One mucosal injury was incurred by a novice. The rate of dissection in the stomach and the oesophagus was not statistically different (P= 0.620). All participants voted that the model provides a realistic simulation and recommended it for training.Conclusions:STER is an advanced endoscopic technique where its indication is currently explored. Experienced and novice STER endoscopists have expressed the usefulness of this model as a training tool. This low-cost model can be used for future research in STER.
authors.affiliation: Division of Upper GI & Metabolic Surgery, Department of Surgery, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Baldwin
authors.initials: B
authors.lastname: Yeung
authors.affiliation: Division of Upper GI & Metabolic Surgery, Department of Surgery, the Chinese University of Hong Kong, Hong Kong, China; Institute of Digestive Disease, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Philip
authors.initials: P
authors.lastname: Chiu
authors.affiliation: Division of Upper GI & Metabolic Surgery, Department of Surgery, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Anthony
authors.initials: A
authors.lastname: Teoh
authors.affiliation: Institute of Digestive Disease, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Linfu
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Division of Upper GI & Metabolic Surgery, Department of Surgery, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Shannon
authors.initials: S
authors.lastname: Chan
authors.affiliation: Institute of Digestive Disease, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Kelvin
authors.initials: K
authors.lastname: Lam
authors.affiliation: Institute of Digestive Disease, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Raymond
authors.initials: R
authors.lastname: Tang
authors.affiliation: Division of Upper GI & Metabolic Surgery, Department of Surgery, the Chinese University of Hong Kong, Hong Kong, China; Institute of Digestive Disease, the Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Enders K W
authors.initials: EK
authors.lastname: Ng