LAUSR

BACKGROUND AND AIMS Water exchange (WE) improves lesion detection but misses polyps due to human limitations. Computer-aided detection (CADe) identifies additional polyps overlooked by the colonoscopist. Additional polyp detection rate (APDR) is the proportion of patients with at least one additional polyp detected by CADe. The number of false positives (FPs) (due to feces and air bubble) per colonoscopy (FPPC) is a major CADe limitation, which might be reduced by salvage cleaning with WE. We compared the APDR and FPPC by CADe between videos of WE and air insufflation in the right colon. METHODS CADe used a convolutional neural network with transfer learning. We edited and coded withdrawal phase videos in a RCT that compared right colon findings between air insufflation and WE. Two experienced blinded endoscopists analyzed the CADe-overlaid videos and identified additional polyps by consensus. An artifact triggered by CADe but not considered a polyp by the reviewers was defined as FP. The primary outcome was APDR. RESULTS A total of 245 coded videos of colonoscopies inserted with WE (n=123) and air insufflation (n=122) methods were analyzed. The APDR in the WE group was significantly higher (37 [30.1%] vs 15 [12.3%], P=0.001). The mean FPPC related to feces (1.78 [1.67] vs 2.09 [2.09], P=0.007) and bubbles (0.53 [0.89] vs1.25 [2.45], P=0.001) in the WE group were significantly lower. CONCLUSION CADe showed significantly higher APDR and lower number of FPPC related to feces and bubbles in the WE group. The results support the hypothesis that the strengths of CADe and WE complement the weaknesses of each other in optimizing polyp detection.