Ex vivo pig training model for esophageal endosopic submucosal dissection (ESD) for endoscopists with experience in gastric ESD

Background Esophageal endoscopic submucosal dissection (ESD) has developed in recent years because of its high rate of en bloc resection. However, for many endoscopists, technical difficulty and risks of complications are great barriers to performing esophageal ESD. In this study, we developed an original training model for esophageal ESD using isolated pig esophagus and assessed this ex vivo model in endoscopists with experience in gastric ESD. Methods Three endoscopists without experience in esophageal ESD but with some experience in gastric ESD performed esophageal ESD of artificial lesions in 10 consecutive sessions using this ex vivo model. The en bloc resection rate, operation time, number of muscularis propria layer injuries, and presence of perforation were recorded. We evaluated the effectiveness of this training in the three endoscopists by comparing results from the first five sessions (former period) with those from the last five sessions (latter period). Results All three endoscopists achieved en bloc resections in all trials. In the former period, injury to the muscularis propria layer for each of the three endoscopists occurred a mean of 2.2 (1-3), 0.6 (0-1), and 3.2 (1-6) times, respectively. Perforation occurred in one session performed by one endoscopist. In the latter period, the mean number of muscularis propria layer injuries for each of the three endoscopists decreased to 0.2 (0-1), 0.2 (0-1), and 0.8 (0-2), respectively. The time of operation shortened from 35.0 (25-40), 36.4 (30-50), and 29.8 (23-43) min to 23.0 (16-31), 25.6 (23-28), and 29.2 (21-37) min, respectively. Conclusions This original ex vivo training model was helpful to endoscopists with experience in gastric ESD in acquiring the basic skills for performing esophageal ESD.