BACKGROUND: In current therapeutic strategies, pyloric stenosis is managed by open or laparoscopic myotomy. Thanks to recent improvements in flexible endoscopic instrumentation and techniques, totally peroral endoscopic approaches could reduce the invasiveness of the procedure. The aim of this study is to establish the feasibility and efficacy of endoscopic submucosal pyloromyotomy in a nonsurvival porcine model.
METHODS AND PROCEDURES: Six pigs were included in this preliminary study. Under general anesthesia, a video-gastroscope equipped with an EMR cap was inserted perorally into the stomach. Serum saline was injected in the submucosal space at the level of the lesser curvature of the antrum, proximal to the pylorus. The gastric mucosa was incised and a 5cm submucosal tunnel was created using a triangle-tip knife towards the pylorus. The circular muscle layer was exposed. Myotomy was performed using the IT-knife until the longitudinal muscle layer was exposed from the antrum to the pyloric ring. Once the myotomy was completed, endoscopic clips were used to re-approximate the mucosal incision. In the last two cases, a manometric catheter was inserted into the duodenum and pyloric resting pressure was measured before and after the myotomy.
RESULTS: Submucosal dissection, identification of the circular muscular layer and myotomy were achieved in all animals. The operative time dropped from 90 minutes (2 first experiments) to 30 minutes in the last 4 animals. Acute complications, including perforation and bleeding, were not observed in any case. Pyloric resting pressure was reduced from 11.5mmHg (mean) to 5mmHg (mean) just after the myotomy.
CONCLUSIONS: Peroral endoscopic submucosal pyloromyotomy has proven to be technically feasible and effective. Potential clinical applications, such as infantile hypertrophic pyloric stenosis or delayed gastric emptying after esophagectomy, could be considered after confirmation of its safety through survival studies.
Session: Video Channel
Program Number: V051