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

<b><i>Background/Aims:</i></b> 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. <b><i>Methods:</i></b> 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). <b><i>Results:</i></b> 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; <i>p</i> &lt; 0.001). The CD value of A5 + CE3 was significantly higher than A3 + CE0 (20.2 ± 6.9 vs. 12.9 ± 5.6, <i>p</i> &lt; 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, <i>p</i> &lt; 0.001). <b><i>Conclusions:</i></b> Higher enhancement settings increased visibility of colorectal lesions.

<b><i>背景与目的：</i></b> 结构与色彩增强（Color Enhancement, CE）参数的调整会改变白光成像的视野，临床工作中常规使用预设的低增强档位。本研究旨在通过内镜医师可见性评分与客观色差（Color Difference, CD）值，探究更高的增强设置是否能够提升结直肠病变的可视性。
<b><i>方法：</i></b> 2015年4月至2015年9月，我们分析了结直肠病变的27张图像与100段视频。对结构增强（Structure Enhancement, B3、A3、A5）与色彩增强（CE 0、1、3）的组合方案进行评估，并使用商用软件计算两种对应模式的色差值：高增强模式（A5+CE3）与预设低增强模式（A3+CE0）。针对视频样本，同样对这两种模式进行评估。所有图像与视频均由4名内镜医师采用可见性评分进行分级，评分范围为4分（优秀）至1分（较差）。
<b><i>结果：</i></b> A3+CE0的评分（2.74±1.09）显著低于所有其他高增强设置方案，包括B3+CE1（3.11±1.08）、A3+CE1（3.33±0.91）及A5+CE3（3.56±0.74；*p* < 0.001）。A5+CE3的色差值显著高于A3+CE0（20.2±6.9 vs. 12.9±5.6，*p* < 0.001）。在视频样本中，A5+CE3的评分同样显著高于A3+CE0（3.27±0.83 vs. 2.53±1.05，*p* < 0.001）。
<b><i>结论：</i></b> 更高的增强设置可提升结直肠病变的内镜可视性。