Ultrathin versus pediatric instruments for colonoscopy in older female patients: A randomized trial

Small-caliber endoscopes such as gastroscopes or pediatric colonoscopes are occasionally required to negotiate fixed or angulated colons. However, the use of a new ultrathin instrument (diameter 7.0 mm) narrower than other conventional colonoscopes has not been evaluated. The aim of the present study was to compare the use compare the use of an ultrathin colonoscope (UTC) with a pediatric colonoscope (PDC) for colonoscopy in older female patients.A prospective, randomized, controlled trial was conducted in a single academic endoscopy unit. A total of 77 female patients aged ≥70 years undergoing unsedated colonoscopy were randomized to colonoscopy with a UTC (n = 39) or PDC (n = 38). Primary outcome measurement was the degree of pain using a numerical rating scale, and secondary outcomes were cecal intubation rate, ileal intubation rate, time to cecum and adenoma detection rate.There was a significant difference in reported pain using the numerical rating scale (median, UTC 1 vs PDC 4, P < 0.0001). Cecal intubation rates were 97.4% in UTC and 92.1% in PDC (P = 0.36), and ileal intubation rates were 82.0% and 89.4% (P = 0.76), respectively. However, median times to cecum were significantly longer using UTC compared with PDC (15.2 min vs 11.1 min, P = 0.022). Adenoma detection rates were 30.7% in UTC and 26.3% in PDC (P = 0.80).Colonoscopy using UTC was almost equivalent to that of PDC in older female patients, with significantly less pain compared with PDC. UTC may be an alternative to PDC for the difficult colon.