Prospective Evaluation of the Clinical Utility of Peroral Endoscopic Myotomy for Gastrointestinal Motility Disorders.

Third space endoscopy, commonly referred as submucosal endoscopy, is founded on the principle that the deeper layers of the gastrointestinal (GI) tract can be accessed by tunneling in the submucosal space without compromising the integrity of the overlying mucosa. Per-oral endoscopic myotomy (POEM) is a prime example of an innovative technique derived from third space endoscopy.