Cecal insertion and withdrawal times with wide-angle versus standard colonoscopes: a randomized controlled trial

The aim of this study was to see if a 170 degrees angle of view (wide angle [WA]) colonoscope allowed faster withdrawal without decreasing adenoma detection.

Eight colonoscopists at 2 institutions participated in the study. Patients were randomized so that each colonoscopist performed 50% of the exams with a 160 series (140 degrees angle of view; standard [ST]) colonoscope and 50% with a prototype 160 series colonoscope with a 170 degrees angle of view (WA instrument). Insertion and withdrawal times and number of polyps detected were recorded. Endoscopists were asked to withdraw as quickly as they could carefully complete the exams. Analysis of variance was done to compare insertion and withdrawal times and number of polyps detected. Time to perform biopsy, polypectomy, and cleaning was subtracted using a stopwatch.

A total of 710 procedures were performed, 355 with ST and 355 with WA colonoscope. The mean insertion time was similar. The mean withdrawal time (absent time for suctioning, washing, etc.) with the WA colonoscope was 4.9 min which was shorter (4.9 vs 5.4 min; P = .0001) overall and for three individual endoscopists (P = .0001, P = .01, and P = .03). There was no difference in the mean number of adenomas detected per colonoscopy with ST (0.6) compared to WA (0.5) (P = .12). Two of the three endoscopists with shorter withdrawal times with WA had numerically higher detection rates with WA.

The WA colonoscope is associated with a reduction in withdrawal time without compromising adenoma detection. However, this effect is operator dependent and the overall impact of wide-angle optics in this study was minor.