Submucosal endoscopy with mucosal flap safety valve.

Area of Science:

• Gastroenterology
• Surgical Innovation
• Endoscopic Research

Background:

• Current endoscopic methods lack reliability for deep gut wall resection or safe peritoneal cavity access.
• Peritoneal soiling remains a significant risk with existing endoscopic techniques.

Purpose of the Study:

• To assess the technical feasibility and safety of submucosal endoscopy with mucosal flap (SEMF).
• To evaluate SEMF for accessing the peritoneal cavity through a full-thickness gastric resection.

Main Methods:

• Ex vivo and in vivo animal studies were conducted.
• A large submucosal working space was created using CO(2) injection and balloon dissection.
• Full-thickness gastric-muscle-wall resection was performed, and the defect was sealed with a mucosal flap and clips/anchors.

Main Results:

• SEMF successfully traversed the gastric wall and accessed the peritoneal cavity in ex vivo and in vivo models.
• The mucosal flap effectively sealed the full-thickness defect, preventing leakage (negative leak tests).
• All animals survived the 1-week follow-up, with minor noted injuries in some.

Conclusions:

• Submucosal endoscopy with mucosal flap (SEMF) is technically feasible for deep-layer gastric wall resection.
• The mucosal flap acts as a reliable valve, preventing peritoneal leakage after endoscopic resection.
• SEMF offers a promising endoscopic approach for accessing the peritoneal cavity.