Linked color imaging improves the visibility of various featured colorectal polyps in an endoscopist's visibility and color difference value.

Purpose: Linked color imaging (LCI) by laser endoscopy is a novel narrow band light observation. In this study, we analyzed the efficacy of LCI for improving the various featured colorectal polyp's visibility utilizing a subjective endoscopist's visibility scoring and objective color difference (CD) value.
Methods: We retrospectively reviewed two pictures both with white light (WL) and LCI for 54 consecutive neoplastic polyps 2-20 mm in size. All pictures were evaluated by four endoscopists according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, we calculated CD value between each polyp and surrounding mucosa in LCI and WL using an original software.
Results: The mean polyp visibility scores of LCI (3.11 ± 1.05) were significantly higher than those of WL (2.50 ± 1.09, P < 0.001). The ratio of an endoscopist's poor visibility (polyp visibility scores 1 and 2) was significantly lower in LCI (27.9%) than WL (55.6%, P < 0.001). With respect to the CD analysis, the CD value of LCI was significantly higher than that of WL (33.3 ± 13.9 vs. 20.7 ± 13.6, P < 0.001). In a subgroup analysis, the polyp visibility scores and CD values of LCI about 24 diminutive polyps (≤5 mm) were higher than those of WL (3.29 ± 0.99 vs. 2.12 ± 0.99, P < 0.001; 31.6 ± 12.8 vs. 14.7 ± 7.6, P < 0.001). Additionally, the polyp visibility scores and CD values of LCI for polyps with any location, size, histology, and morphology were significantly higher than those of WL.
Conclusions: LCI improved the various featured polyp's visibility compared to WL in both polyp visibility scores and CD value.