Clin Endosc.  2021 Jul;54(4):488-493. 10.5946/ce.2021.157.

Clinical Applications of Linked Color Imaging and Blue Laser/Light Imaging in the Screening, Diagnosis, and Treatment of Superficial Colorectal Tumors

• Sakamoto T
• Cho H
• Saito Y

• KMID: 2518850
• DOI: http://doi.org/10.5946/ce.2021.157

Abstract

Considering its contribution to reducing colorectal cancer morbidity and mortality, the most important task of colonoscopy is to find all existing polyps. Moreover, the accurate detection of existing polyps determines the risk of colorectal cancer morbidity and is an important factor in deciding the appropriate surveillance program for patients. Image-enhanced endoscopy is an easy-to-use modality with improved lesion detection. Linked color imaging (LCI) and blue laser/light imaging (BLI) are useful modalities for improving colonoscopy quality. Each mode has unique optical features; therefore, their intended use differs. LCI contributes to improved polyp detection due to its brightness and high color contrast between the lesion and normal mucosa, while BLI contributes to the characterization of detected polyps by evaluating the vessel and surface patterns of detected lesions. The proper use of these observation modes allows for more efficient endoscopic diagnosis. Moreover, recent developments in artificial intelligence will soon change the clinical practice of colonoscopy and this system will provide an efficient education modality for novice endoscopists.

Keyword

Blue laser/light imaging; Colonoscopy; Linked color imaging; Superficial colorectal tumor

Figure

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  Fig. 1. Wavelength differences among the three observation modes. (A) White light imaging (WLI). (B) Blue laser/light imaging (BLI). (C) Linked color imaging (LCI).

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  Fig. 2. Differences in brightness among the three observation modes. (A) Linked color imaging (LCI). (B) White light imaging (WLI). (C) Blue laser/light imaging (BLI).

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  Fig. 3. An example of the clinical application of the three observation modes. (A, B) White light imaging (WLI) or linked color imaging (LCI) for the detection of polyps. (C) Characterization or depth diagnosis was performed by evaluating the vessels and surface pattern using magnifying blue laser/light imaging (BLI). Irregular vessel and surface patterns are shown in the center of the lesion. (D) Chromoendoscopy with crystal violet staining was additionally performed to confirm the depth diagnosis as a final judgment. A severe irregular pit pattern was found at the center of the lesion. From this finding, the depth diagnosis was a deep submucosal invasion.

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  Fig. 4. CAD-EYE system. (A) Detection of a colorectal polyp with linked color imaging (LCI) and computer-aided detection (CADe system). (B) The polyp was then characterized by blue laser/light imaging (BLI) and computer-aided diagnosis (CADx system).

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