Explore more content after your registration

»Register here«

Publications on Blue Laser / BLI

Evaluation of the visibility of early gastric cancer using linked color imaging and blue laser imaging.

Yoshifuku Y1, Sanomura Y2, Oka S1, Kurihara M1, Mizumoto T1, Miwata T1, Urabe Y1, Hiyama T3, Tanaka S4, Chayama K1.

BMC Gastroenterol. 2017 Dec 8;17(1):150.

Background: Blue laser imaging (BLI) and linked color imaging (LCI) are the color enhancement features of the LASEREO endoscopic system, which provide a narrow band light observation function and expansion and reduction of the color information, respectively.

Methods: We examined 82 patients with early gastric cancer (EGC) diagnosed between April 2014 and August 2015. Five expert and 5 non-expert endoscopists retrospectively compared images obtained on non-magnifying BLI bright mode (BLI-BRT) and LCI with those obtained via conventional white light imaging (WLI). Interobserver agreement was also assessed.

Results: In experts’ evaluation of the images, an improvement in visibility was observed in 73% (60/82) and 20% (16/82) of cases under LCI and BLI-BRT, respectively. In non-experts’ evaluation of the images, an improvement in visibility was observed in 76.8% (63/82) and 24.3% (20/82) of cases under LCI and BLI-BRT, respectively. There were no significant differences between experts and non-experts in the evaluation of the images. The improvement in visibility was significantly higher with LCI than with BLI-BRT in experts and non-experts (p < 0.01). With regard to tumor color on WLI, the improvement in the visibility of reddish and whitish tumors was significantly higher than that of isochromatic tumors when LCI was used. The improvement in visibility with LCI was observed in 71% (12/17) and 74% (48/65) of patients with and without Helicobacter pylori (Hp) eradication, respectively; no significant difference in improvement was observed between these groups. The interobserver agreement was good to satisfactory at ≥ 0.62.

Conclusions: In conclusion, our study showed that LCI improved the visibility of EGC, regardless of the level of endoscopists’ experience or Hp eradication in patients, particularly for EGCs with a reddish or whitish color. The improvement in visibility was significantly higher with LCI than that with BLI.


1 Department of Gastroenterology and Metabolism, Graduate School of Biomedical Sciences, Hiroshima University, Japan.
2 Department of Endoscopy, Hiroshima University Hospital, Japan.
3 Health Service Center, Hiroshima University, Japan.
4 Department of Endoscopy, Hiroshima University Hospital, Japan.

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

Yoshida N, Naito Y,  Itoh Y. et al.

Int J Colorectal Dis. 2017 Jul 19. doi: 10.1007/s00384-017-2855-z.

Background and study aims: Linked color imaging (LCI) and blue laser imaging (BLI) are novel image-enhanced endoscopy technologies with strong, unique color enhancement. We investigated the efficacy of LCI and BLI-bright compared to conventional white light imaging (WLI) by measuring the color difference between early gastric cancer lesions and the surrounding mucosa.

Patients and methods: Images of early gastric cancer scheduled for endoscopic submucosal dissection were captured by LCI, BLI-bright, and WLI under the same conditions. Color values of the lesion and surrounding mucosa were defined as the average of the color value in each region of interest. Color differences between the lesion and surrounding mucosa (ΔE) were examined in each mode. The color value was assessed using the CIE L*a*b* color space (CIE: Commission Internationale d’Eclairage).

Results: We collected images of 43 lesions from 42 patients. Average ΔE values with LCI, BLI-bright, and WLI were 11.02, 5.04, and 5.99, respectively. The ΔE was significantly higher with LCI than with WLI ( P  < 0.001). Limited to cases of small ΔE with WLI, the ΔE was approximately 3 times higher with LCI than with WLI (7.18 vs. 2.25). The ΔE with LCI was larger when the surrounding mucosa had severe intestinal metaplasia ( P  = 0.04). The average color value of a lesion and the surrounding mucosa differed. This value did not have a sufficient cut-off point between the lesion and surrounding mucosa to distinguish them, even with LCI.

Conclusion: LCI had a larger ΔE than WLI. It may allow easy recognition and early detection of gastric cancer, even for inexperienced endoscopists.

BASIC (BLI Adenoma Serrated International Classification) classification study for colorectal polyp characterization with blue light imaging

Raf Bisschops1, Cesare Hassan2,3, Pradeep Bhandari4, Emmanuel Coron5, Helmut Neumann6, Oliver Pech7, Loredana Correale2, Alessandro Repici3

Endoscopy 2018; 50: 1-17 / https://doi.org/10.1055/s-0043-121570

Backgound and study aim: Advanced endoscopic imaging has revolutionized the characterization of lesions during colonoscopy. The aim of this study was to create a new classification for differentiating subcentimetric hyperplastic and adenomatous polyps, and deeply invasive malignant lesions using blue-light imaging (BLI) with high definition, with and without optical magnification, as well as to assess its interobserver concordance.

Methods: A video library consisting of 48 videos/still images (with/without optical magnification) from 24 histologically verified polyps/cancer with BLI was prospectively created. In the first step, seven endoscopists with experience in electronic chromoendoscopy reviewed 12 BLI videos/still images with/without magnification representative of the different histotypes, and individually identified possible descriptors. In the second step, these descriptors were categorized and summarized with a modified Delphi methodology. In the third step, the seven endoscopists independently reviewed the remaining 36 videos/still images with/without optical magnification, and the interobserver agreement for the new descriptors was assessed. The interobserver agreement between endoscopists was assessed using Gwet’s AC1.

Results: By reviewing the initial 12 videos/still images, 43 descriptors were proposed. By a modified Delphi process, the endoscopists eventually agreed on summarizing 12 descriptors into three main domains. The main domains identified were: polyp surface (mucus, yes/no; regular/irregular; [pseudo]depressed, yes/no), pit appearance (featureless, yes/no; round/nonround with/without dark spots; homogeneous/heterogeneous distribution with/without focal loss), and vessels (present/absent, lacy, pericryptal, irregular). Interobserver agreement for the polyp surface domain appeared to be almost perfect for mucus (AC1 0.92 with and 0.88 without optical magnification), substantial for the regular/irregular surface (AC1 0.67 with and 0.66 without optical magnification). For the pit appearance domain, interobserver agreement was good for featureless (AC1 0.9 with and 0.8 without optical magnification), and round/nonround (AC1 0.77 with and 0.69 without optical magnification) descriptors, but less consistent for the homogeneity of distribution (AC1 with/without optical magnification 0.58). Agreement was almost perfect for the vessel domain (AC1 0.81 – 0.85).

Conclusions: The new BASIC classification takes into account both morphological features of the polyp, as well as crypt and vessel characteristics. A high concordance among the observers was shown for most of the summarized descriptors. Optical magnification had a beneficial effect in terms of interobserver agreement for most of the descriptors.

1 Department of Gastroenterology and Hepatology, Catholic University of Leuven (KUL), TARGID, University Hospitals Leuven, Leuven, Belgium.
2 Gastroenterology, Nuovo Regina Margherita Hospital, Rome, Italy.
3 Digestive Endoscopy Unit, Humanitas University, Milan, Italy.
4 Solent Centre for Digestive Diseases, Portsmouth Hospital, Portsmouth, United Kingdom.
5 Hepatogastroenterology, Centre Hospitalier Universitaire Hotel Dieu, Nantes, France.
6 First Medical Department, University Medical Center Mainz, Mainz, Germany.
7 Department of Gastroenterology and Interventional Endoscopy, Krankenhaus Barmherzige Brüder Regensburg, Regensburg, Germany.

PDF

Laser Imaging Facilitates Early Detection of Synchronous Adenocarcinomas in Patients with Barrett’s Esophagus.

Iwashita C, Miura Y

Clin Endosc. 2017 Jan;50(1): Impact factor 0.94

Abstract: Barrett’s adenocarcinoma may occur in multiple sites, and recurrence and metachronous lesions are the major problems with endoscopic resection. Therefore, early detection of such lesions is ideal to achieve complete resection and obtain improved survival rates with minimally invasive treatment. Laser imaging systems allow multiple modalities of endoscopic imaging by using white light laser, flexible spectral imaging color enhancement (FICE), blue laser imaging (BLI), and linked color imaging even at a distant view. However, the usefulness of these modalities has not been sufficiently reported regarding Barrett’s adenocarcinoma. Here, we report on a patient with three synchronous lesions followed by one metachronous lesion in a long segment with changes of Barrett’s esophagus, all diagnosed with this new laser endoscopic imaging system and enhanced by using FICE and/or BLI with high contrast compared with the surrounding mucosa. Laser endoscopic imaging may facilitate the detection of malignancies in patients with early Barrett’s adenocarcinoma.

Blue Laser Imaging-Bright Improves Endoscopic Recognition of Superficial Esophageal Squamous Cell Carcinoma.

Tomie A, Dohi O

Gastroenterol Res Pract. 2016;2016:6140854. Epub 2016 Sep 22. Impact factor 1.742

Abstract: The aim of this study was to evaluate the endoscopic recognition of esophageal squamous cell carcinoma (ESCC) using four different methods (Olympus white light imaging (O-WLI), Fujifilm white light imaging (F-WLI), narrow band imaging (NBI), and blue laser imaging- (BLI-) bright). Methods. We retrospectively analyzed 25 superficial ESCCs that had been examined using the four different methods. Subjective evaluation was provided by three endoscopists as a ranking score (RS) of each image based on the ease of detection of the cancerous area. For the objective evaluation we calculated the color difference scores (CDS) between the cancerous and noncancerous areas with each of the four methods.

Results: There was no difference between the mean RS of O-WLI and F-WLI. The mean RS of NBI was significantly higher than that of O-WLI and that of BLI-bright was significantly higher than that of F-WLI. Moreover, the mean RS of BLI-bright was significantly higher than that of NBI. Furthermore, in the objective evaluation, the mean CDS of BLI-bright was significantly higher than that of O-WLI, F-WLI, and NBI.

Conclusion: The recognition of superficial ESCC using BLI-bright was more efficacious than the other methods tested both subjectively and objectively.

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

Togashi K, Nemoto D etc

Therap Adv Gastroenterol. 2016 Jan;9(1): Impact factor 3.883

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.