Use of an overtube for enteroscopy - Does it increase depth of insertion? A prospective study of enteroscopy with and without an overtube

Background and Study Aims: Although a stiffening overtube is commonly used with push enteroscopy, in the belief that this will allow increased inserti on into the small intestine, there is no prospective data to support this v iew The aim of this study is to prospectively study the depth of insertion into the small intestine at enteroscopy with and without an overtube. Patients and Methods: A total of 38 patients referred for enteroscopy were prospectively studied. Alternate enteroscopies were performed with or witho ut an overtube; therefore 19 patients had enteroscopy with and 19 without a n overtube. The groups were well matched for age, sex, indication, use of f luoroscopy, and dedicated anesthetic assistance. Depth of insertion was ass essed by advancing the enteroscope as far as possible, then straightening t he enteroscope until the tip began withdrawing. The difference between the straightened insertion depth and the distance from the incisors to the pylo rus was recorded as the insertion depth beyond the pylorus. This was consid ered the major end point. Statistical analysis was performed using the Mann -Whitney test for nonparametric data. Results: The median straightened total insertion depth from the incisors wa s greater when enteroscopy was performed with an overtube compared with ent eroscopy without an overtube (125 cm vs. 110 cm, P = 0.05). The median stra ightened insertion depth beyond the pylorus was significantly greater with overtube use (70 cm vs. 50 cm, P = 0.01). No significant difference between the groups was observed in terms of the likelihood of significant findings at enteroscopy. Conclusions: Use of an overtube for push enteroscopy results in significant ly deeper insertion into the small intestine. Although a larger study would be needed to demonstrate an increase in diagnostic yield and to confirm th e safety of overtube use, this study does provide the first objective evide nce of an advantage in terms of insertion depth.