Single Balloon Enteroscope for Complete Colonic Examination in Patients with Failed Colonoscopy

Abstract

Purpose: Colonoscopy is the gold standard for colorectal cancer screening, and the success rate of completion approaches 95%. Failures are due to multiple factors including: patient anatomy, prior surgery, bowel looping, poor bowel prep, and patient discomfort. If the cecum cannot be intubated, the exam is considered incomplete. If this occurs standard options for complete evaluation include air contrast barium enema, repeat colonoscopy, or CT colonography. We have recently used a single balloon enteroscope (SBE) to reach the cecum as an alternative method for a complete colonic exam in patients failing conventional colonoscopy. Methods: Standard colonoscopy was performed with an Olympus PCF Q160 AL or Q180 AL colonoscope. SBE was performed with the Olympus SIF Q180. An overtube was used for all SBE procedures. Each time the overtube was advanced, a subsequent loop reduction maneuver was performed. Propofol was administered by an anesthesiologist for sedation. Patients who had an incomplete examination due to a poor preparation were excluded. Results: Twelve consecutive patients failing standard colonoscopy were entered into the study. Eight females and four males with a mean age of 60.3 years (range 47-71). The indications for colonoscopy were average risk screening (2), personal history of colon polyps (6), family history of colorectal cancer (2), and hematochezia (2). Six patients had a history of prior abdominal or pelvic surgery. Colonoscopy to the cecum was successful in all twelve patients. Mean procedure time was 38.9 min (range 22-71 min). The balloon on the overtube was inflated only once in one case. Five of the patients had findings proximal to the area reached on prior colonoscopy, 4 patients with adenomas and 1 with cecal ulcerations. Conclusion: Limited information exists on using SBE as an alternative method for screening colonoscopy in difficult cases. The SBE is longer, smaller in diameter, and more flexible than a standard colonoscope. The overtube adds stiffness but remains flexible enough to traverse colonic loops. Colonoscopy using the SBE allows direct visualization of the colon with potential endsocopic therapy, whereas the alternative imaging techniques would require subsequent endoscopy for evaluation. The flexibility of the SBE allows for easy retroflexion and retroflexed withdrawal, thus providing views of posterior aspects of folds which would otherwise go unseen. Limitations of the SBE include a longer time spent suctioning fluid due to the longer and smaller diameter suction channel, and the need for assistance to control the longer endoscope and overtube. Given the above results, colonoscopy with a SBE should be considered a viable option for evaluating the colon in patients who fail standard colonoscopy.