Initial Experience with Retrograde Overtube-Assisted Enteroscopy Using a Spiral Tip Overtube (Clinical Report‪)‬

Endoscopic evaluation of the small bowel improved significantly with video capsule endoscopy, but limitations include the inability to manipulate it and lack of therapy (1-3). Push enteroscopy also has limitations due to gastric looping, which limits the ability to transmit axial force onto the endoscope (1, 2). Older overtubes that attempted to reduce loop formation did little to improve depth of insertion, and mucosal trauma and perforations were not uncommon (4-6). Overtube-assisted enteroscopy (OAE) is a dynamic procedure that complements the endoscope, beyond just straightening the gastric loop. It has improved the diagnostic and therapeutic endoscopic abilities for small bowel disease, and antegrade, or per-oral, and retrograde, or trans-anal, approaches have been described (1, 2, 7). The double-balloon overtube has been more widely studied, and depths of insertion of 200 cm from the ligament of Treitz and 130 cm from the ileocecal valve in the retrograde approach have been reported (8, 9). Data for the single-balloon overtube for OAE are more limited, but panenteroscopy has also been reported (10, 11). Complete small bowel enteroscopy has been more frequently reported outside the United States (12--15). Therapeutic enteroscopy, including hemostasis, stricture dilatation, foreign body removal, and polypectomy, has been reported for both double-balloon and single-balloon OAE (16--23).