Kits and methods for submucosal endoscopic access into body cavities such as the peritoneal cavity and the posterior mediastinum through a submucosal endoscopic procedure in which an opening is formed through the muscularis propria within a bleb. The procedure may result in a mucosal flap formed by separated mucosal tissue within the bleb and the mucosal flap may be advantageously used to assist in closure of the opening.
