Novel technique of auto-tunneling during peroral endoscopic myotomy (with video)

Background Peroral endoscopic myotomy (POEM) was developed to reduce lower esophageal sphincter pressure in patients with achalasia. POEM is technically challenging and time consuming. The creation of an esophageal submucosal tunnel is a major and integral part of the procedure. Dissection of the submucosal fibers is a lengthy task. Objective To present our initial experience with the use of a novel gel with dissecting properties for facilitating submucosal tunneling during POEM. Setting Johns Hopkins Hospital. Intervention POEM. Results The gastroscope was successfully introduced into the submucosal space in all pigs. The gel in the submucosal space was easily suctioned through the working channel of the gastroscope and did not interfere with endoscopic visualization. The esophageal submucosal tunnel was noted to be already formed upon entry into the submucosal space in all 5 pigs. Esophageal submucosal dissection was not required in any case. "Auto-tunneling" by the dissecting gel stopped at the level of the lower esophageal sphincter. Further tunneling into the gastric cardia was needed in all pigs. The average procedure (including myotomy) time was 28 minutes. Limitations Animal experiments. Conclusion Gel consistently resulted in efficient auto-tunneling without any complications. This gel has the potential to revolutionize POEM and endoscopic submucosal dissection if its safety and efficacy are replicated in other animal studies and subsequently in human trials.