Disclosed herein are intestine pleating methods and devices for use with gastrointestinal endoscopes. Devices include balloon access device, attachable structure(s), and an elongate overtube. Attachable structures may be used to pleat intestinal wall and to advance the endoscope past difficult to navigate areas. Balloon access device may be used to improve visualization of intestinal wall and to pleat intestinal wall. These systems may be used during airless endoscopic procedures that do not require insufflation of the intestinal cavity. The systems may be used during airless intubation procedures. To pleat the intestine, the practitioner inflates balloon to a fully or nearly fully inflated state when a difficult area is encountered. Inflation of the balloon to fully or nearly fully inflated state ensures contact with intestinal wall. Practitioner pulls back on the endoscope shaft to drag intestinal wall back toward the proximal opening of intestinal cavity. Pleating facilitates forward advancement of endoscope.