Blue laser imaging endoscopy system for the early detection and characterization of colorectal lesions: a guide for the endoscopist

Abstract

Blue laser imaging is a new system for image-enhanced endoscopy using laser light. Blue laser imaging utilizes two monochromatic lasers (410 and 450 nm) instead of xenon light. A 410 nm laser visualizes vascular microarchitecture, similar to narrow band imaging, and a 450 nm laser provides white light by excitation. According to three recently published reports, the diagnostic ability of polyp characterization using blue laser imaging compares favorably with narrow band imaging. No published data are available to date regarding polyp detection with blue laser imaging. However, blue laser imaging has the possibility to increase the detection of colorectal polyps by depicting brighter and clearer endoscopic images, even at a distant view, compared with first-generation image-enhanced endoscopy. A clinical trial to compare the detection between blue laser imaging and xenon light is warranted.

Keywords: blue laser imaging; colon polyp; colorectal cancer; colorectal neoplasm; image enhanced endoscopy; magnification colonoscopy.

Conflict of interest statement

Conflict of interest statement: The authors declare no conflicts of interest in preparing this article.

Figures

Figure 1.

Laser illumination using two lasers and white light phosphor. A 410 nm laser looks blue light. A 450 nm laser stimulates the white light phosphor in the tip of the scope to produce the broadband white light.

Figure 2.

Light spectrum in each mode. Note: white light mode contains 410 nm laser light.

Figure 3.

(A) White-light mode. A sessile adenoma measuring 6 mm in size is clearly identified, but its superficial structure is not depicted clearly. (B) BLI-bright mode. Surrounding normal mucosa is depicted clearly and brightly even in a distant view. The vessel pattern of the polyp as well as the surface pattern is clearly depicted without magnification. (C) BLI mode. Magnified view shows a regular structure, suggesting a low-grade adenoma.

Figure 4.

(A) White-light mode. A hyperplastic polyp measuring 6 mm shows a pale appearance. (B) BLI-bright mode. Demarcation line of the polyp is clearly seen in a distant view. (C) BLI mode. Magnified view does not show any distinct structure, but only small vessels are observed on the polyp surface, suggesting a non-neoplastic polyp.

Figure 5.

(A) White-light mode. Laterally spreading tumor measuring 28 mm in maximum size is clearly identified in a plain image. (B) BLI mode. Magnified view shows regularly arranged structure, suggesting a low-grade tubular adenoma.

Figure 6.

(A). White-light mode. Protruding tumor measuring 18 mm shows an irregular surface in a plain image. (B) BLI mode. Magnified view shows an irregular vascular pattern and an avascular area can be seen partially. Surface pattern also shows irregularity. These finding definitely indicates substantially invasive cancer.