Supplementary Material for: High Enhancement Settings for White Light Observation Improves Colorectal Polyp Visibility in Color Difference Value and an Endoscopist’s Visibility

Background/Aims: Settings of structure and color enhancement (CE) change view of white light imaging and a preset low enhancement setting is used regularly. The aim of this study was to investigate whether higher enhancement settings increased colorectal lesions’ visibility with endoscopists’ visibility scoring and objective color difference (CD) value. Methods: From April 2015 to September 2015, we analyzed 27 pictures and 100 videos of colorectal lesions. Combinations of structure enhancement (B3, A3, A5) and CE (CE 0, 1, 3) were evaluated and CD values of 2 corresponding modes (high enhancement: A5 + CE3, preset low enhancement: A3 + CE0) were calculated using marketed software. In the video, these 2 modes were evaluated. All pictures and movies were graded by 4 endoscopists using visibility scores: score 4 (excellent) to score 1 (poor). Results: The scores of A3 + CE0 (2.74 ± 1.09) were significantly lower than those of all other higher enhancement settings such as B3 + CE1 (3.11 ± 1.08), A3 + CE1 (3.33 ± 0.91), and A5 + CE3 (3.56 ± 0.74; p < 0.001). The CD value of A5 + CE3 was significantly higher than A3 + CE0 (20.2 ± 6.9 vs. 12.9 ± 5.6, p < 0.001). In the video, the scores for A5 + CE3 were significantly higher than A3 + CE0 (3.27 ± 0.83 vs. 2.53 ± 1.05, p < 0.001). Conclusions: Higher enhancement settings increased visibility of colorectal lesions.