Prolonged Cecal Insertion Time Is Not Associated with Decreased Adenoma Detection When a Longer Withdrawal Time Is Achieved

Background: The association between withdrawal time and adenoma detection has been established; however, the effect of cecal insertion time on adenoma detection remains unclear. Aim: To determine the association between cecal insertion time and adenoma detection. Methods: This study completed a retrospective analysis of data collected in 4 prospective randomized-controlled trials related to screening and surveillance colonoscopy at a single tertiary care from 2010 to 2016. The primary outcome was cecal insertion time and its association with mean number of adenomas per patient and adenoma detection rate (ADR). Results: 1303 patients met inclusion criteria (average age 59.7 ± 8.7 years; 759 females (58.3%), and 763 Caucasians (58.6%). Mean cecal insertion time was significantly longer in patients who were female (p < 0.001), received moderate sedation (p = 0.001), had fellow involvement (p < 0.001), older (p = 0.002), and lower Boston bowel preparation scale (p < 0.001). Withdrawal time was found to increase as mean cecal insertion time increased (p < 0.001). The mean cecal insertion time was not different in patients with or without adenomas (p = 0.94). Cecal insertion time did not correlate with the mean number of adenomas or advanced adenomas per patient (p > 0.05), which was also true on Poisson regression analysis. Adenomas and advanced adenomas per patient were found to decrease when cecal insertion to withdrawal time ratios were greater than 1 (p < 0.001). Conclusions: Prolonged cecal insertion time was not associated with a decrease in ADR, mean number of adenomas or advanced adenomas per patient. When withdrawal times were longer than cecal insertion times, the number of adenomas and advanced adenomas detected per patient was significantly improved.