170° Wide-Angle Colonoscope: Effect on Efficiency and Miss Rates.

BACKGROUND: Small polyps are routinely missed during colonoscopy even with careful examination. AIM: To determine and compare endoscopic efficiency and polyp miss rate between a prototype 1700 wide-angle (WA) colonoscope and a standard (S) colonoscope. METHODS: Two consecutive same-day colonoscopies were performed in 50 patients with intact colons. The patients were randomized to undergo the first colonoscopy with either the prototype WA 170° angle of view colonoscope or an S adult 140° angle of view colonoscope. RESULTS: The mean time for insertion was 2.09 (1.09) mm versus 2.53 (1.47) mm (p = 0.002) for the WA colonoscope and the S colonoscope, respectively. Similarly, the mean time for examination during withdrawal was shorter with the WA colonoscope (4.98 (0.94) vs 5.74 (1.12) mm; p <0.0001). The mean insertion time for the second examination was shorter than the insertion time for the first examination, irrespective of the colonoscope (p = 0.006). However, the withdrawal times were not significantly different between the first and second examinations (p = 0.11). The miss rate for all polyps with the WA colonoscope (19%) was similar to the miss rate with the S colonoscope (27%; p = 0.19). The miss rates for adenomas with the WA (10/33; 30.3%) and the S scope (15/50; 30%) were similar (p = 0.98). CONCLUSIONS: The use of the WA colonoscope was associated with a reduction in insertion time to the cecum, as well as examination time during withdrawal. No evidence was found that the accuracy of the two colonoscopes differs. [ABSTRACT FROM AUTHOR]