Enteroscopy Stiffening Device for Retrograde Balloon Assisted Enteroscopy

Overview

Balloon assisted enteroscopy has revolutionized the management of small bowel diseases by enabling endoscopic access deep into the small bowel. Using a combination of antegrade (through the mouth) and retrograde (through the anus) approaches, a large portion of the small bowel can be examined. Access to the proximal small bowel through the pylorus using the antegrade approach is straightforward but intubating the distal small bowel through the ileocecal valve is challenging due to the flexibility of the enteroscope. Recently, an enteroscopy stiffening wire has been developed. The purpose of our double blind placebo controlled randomized cross over study is to evaluate the performance of the enteroscopy stiffening wire in achieving terminal ileum intubation (TI) during retrograde balloon assisted enteroscopy.

Small bowel endoscopy has undergone a paradigm shift in the past decade. Prior to this, the small bowel was considered a 'black hole' due to our inability to visualize it endoscopically and the limited sensitivity of radiologic studies. This all changed with the development of video capsule endoscopy, which gave physicians the ability to visualize the full length of the small bowel. Although widely considered a great leap forward, video capsule endoscopy is limited by its inability to perform any form of endoscopic intervention. Thus, something was needed to biopsy and treat the diseases detected with video capsule endoscopy. Double balloon enteroscopy (DBE) was invented in Japan in 2001.(1) Using an overtube and two inflatable balloons, DBE enabled deep intubation of the small bowel through a series of push and pull maneuvers to accordion the small bowel over the overtube. This procedure proved highly successful in the diagnosis and treatment of small bowel diseases.(2, 3) Subsequently, single balloon enteroscopy (SBE) was developed consisting of a single overtube balloon.(4, 5) Collectively, these techniques are called balloon assisted enteroscopy. Balloon assisted enteroscopy can be performed using an antegrade (through the mouth) or retrograde (through the anus) approach. The two approaches are considered complimentary since the antegrade approach enables visualization of the proximal and mid small bowel while the distal portion is seen with the retrograde approach. Of the two, the retrograde approach is more challenging as it requires first going through the length of the colon followed by intubation of the terminal ileum (TI) to reach the small bowel. TI intubation during balloon assisted enteroscopy can be difficult due to the inherent flexibility of the enteroscope.(6) Even in expert hands, the success rate for TI intubation ranges between 69-79% (7-9) and takes on average 28 minutes to intubate once the cecum has been reached.(8) Patients with distal ileum lesions who fail retrograde balloon assisted enteroscopy have limited options and may require surgery. Recently, an enteroscopy stiffening wire has been developed by Zutron Medical LLC (Kansas, USA). This is a through the scope wire that stiffens the enteroscope to increase the maximal depth of insertion. Since the difficulty in intubating the TI during retrograde balloon assisted enteroscopy is largely due to the inherent flexibility of the enteroscope, a stiffening wire may improve the ease of TI intubation. The objective of our double blind placebo controlled crossover study is to evaluate the performance of the enteroscopy stiffening wire in improving TI intubation.