Colonoscopy using a small-caliber colonoscope with passive-bending after incomplete colonoscopy due to sharp angulation or pain

We evaluated the performance of a newly developed small-caliber (SC) colonoscope (PCF-PQ260L). This colonoscope (diameter 9.2 mm) is designed with passive-bending and high-force transmission. The SC colonoscope was used for rescue colonoscopy following incomplete colonoscopy with a standard (SD) colonoscope caused by sharp angulation, loop formation, or pain. Records of SC colonoscopy given to patients following an incomplete colonoscopy with the SD colonoscope and in the same session were analyzed. Cecal intubation rate, pain using a visual analog scale (0 = none, 100 = extremely painful) in the first and second colonoscopy, total time, new lesions detected with the SC colonoscopy, dosage of sedation used, and any complications were assessed. Examinations that could not be completed, because the colonoscope was not long enough to reach the cecum due to a redundant colon were excluded. The records of 43 patients who were given SC colonoscopy following incomplete examinations using the SD colonoscope were reviewed. In 97.7 % of cases (42/43), cecal intubation was achieved with the SC colonoscope in the same session. The mean pain score during colonoscopy was significantly lower for the second SC colonoscopy than for the first SD colonoscopy (40.6 ± 14.1 vs. 74.5 ± 10.8, P