Deng P¹, Min M¹, Dong T¹, Bi Y¹, Tang A¹, Liu Y¹

Endosc Int Open. 2018 Oct;6(10):E1177-E1183. doi: 10.1055/a-0602-3997. Epub 2018 Oct 8.

Background and study aims: Non-erosive reflux disease (NERD) includes minimal change esophagitis (MCE) and no endoscopic abnormalities. However, for most endoscopists, it is difficult to detect MCE with conventional white-light endoscopy (WLE). Linked color imaging (LCI) technology is the most recently developed image-enhancing technology and improves detection and differentiation of subtle mucosal changes using a color contrast method. This study assessed the efficacy of WLE combined with LCI for diagnosing MCE compared with WLE.

Patients and methods: Between February and May 2017, 44 NERD patients and 40 healthy subjects were enrolled in our study. First, the distal esophagus was examined using WLE followed by LCI. Second, three experienced endoscopists observed all the patients’ white-light (WL) images and corresponding images of WL and LCI and then recorded presence or absence of minimal change esophagitis (MCE +/-). The proportion of minimal change between the two groups was then compared. Third, five blinded endoscopists with different levels of endoscopic experience assessed whether MCE was present. Intraobserver reproducibility and interobserver agreement were described using the kappa value.

Results: The proportion of MCE in the NERD group (70.8 %, 35/48) was higher than that in the control group (22.5 %, 9/40, P  < 0.001) when diagnosed by the three experienced endoscopists. Detection rates for MCE using WLE combined with LCI were higher than those using WLE (43/88, 48.9 % vs. 29/88, 33.0 %, P  < 0.001). With WLE combined with LCI, intraobserver reproducibility significantly improved, indicating that the combined approach can improve interobserver agreement compared with using WLE alone.

Conclusions:  Endoscopic diagnosis of MCE using WLE combined with LCI images is effective. Intraobserver reproducibility and interobserver agreement in MCE can be improved when LCI is applied with conventional imaging.

1 Department of Gastroenterology and Hepatology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, China

Fukuda H¹, Miura Y¹, Osawa H², Takezawa T¹, Ino Y¹, Okada M¹, Khurelbaatar T¹, Lefor AK¹, Yamamoto H¹.

J Gastroenterol. 2018 Oct 5. doi: 10.1007/s00535-018-1515-6. [Epub ahead of print]

Background: Linked color imaging (LCI) increases the visibility of early gastric cancers, which may be associated with characteristic findings including background purple mucosae. These lesions are found in areas of chronic gastritis and surrounding mucosa. The aim of this study is to objectively characterize these lesions by color differences and color component values using LCI.

Methods: Fifty-two patients with early gastric cancer were enrolled. Color differences were calculated prospectively in malignant lesions and adjacent mucosa and compared with histological findings in resected specimens. Color component values of L, a, and b* were compared between purple and non-purple mucosae in areas of chronic gastritis. Based on histological findings, the accuracy of identifying gastric intestinal metaplasia was calculated.

Results: Cancers and surrounding mucosa in 74% of lesions had similar colors using white light imaging (WLI), whereas purple mucosa surrounded part or all of cancers appearing orange-red, orange or orange-white using LCI. Greater color differences were seen using LCI compared to WLI, including flat-type cancers, leading to higher contrast. The surrounding purple mucosa corresponded histologically to intestinal metaplasia, facilitating the identification of malignant lesions. Forty lesions (83%) with purple mucosa and eight lesions (17%) with non-purple mucosa in areas of chronic gastritis were diagnosed as intestinal metaplasia by biopsy (83% accuracy). Color component values of purple mucosa differ significantly from those of non-purple mucosae.

Conclusions: LCI images have higher color contrast between early gastric cancers and surrounding mucosa compared to WLI. A characteristic purple color around gastric cancers using LCI represents intestinal metaplasia.

1 Division of Gastroenterology, Department of Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
2 Department of Surgery, Jichi Medical University, Shimotsuke, Japan

Masaya Iwamuro ², Hiroyuki Sakae ¹, Hiromitsu Kanzaki ¹, PhD Hiroyuki Okada ²

Journal of General and Family Medicine

Abstract: Esophagogastroduodenoscopic examination shows diffuse redness of the mucosa of the gastric body, which can be identified as a deep reddish color. The present case underscores the importance of diffuse redness as a key endoscopic feature that enables prompt diagnosis of current Helicobacter pylori infection.

1 Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry
2 Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan

Yoshida N¹, Inada Y², Yasuda R¹, Murakami T¹, Hirose R¹, Inoue K¹, Dohi O¹, Naito Y¹, Ogiso K³, Morinaga Y⁴, Kishimoto M⁴, Konishi E⁴, Itoh Y¹.

Gastroenterol Res Pract. 2018 Jul 8;2018:5059834. doi: 10.1155/2018/5059834. eCollection 2018.

Background and aims: Missed polyps are a pitfall of colonoscopy. In this study, we analyzed the efficacy of an additional 30 seconds observation using linked color imaging (LCI) for detecting adenoma and sessile serrated adenoma/polyp (SSA/P).

Materials and methods: We enrolled patients undergoing colonoscopy from February to October 2017 in two institutions. In all patients, the cecum and ascending colon were observed with white light imaging (WLI) first. The colonoscope was inserted again, and the cecum and ascending colon were observed for an additional 30 seconds using either LCI or WLI. The method for the 30 sec observation was to insufflate the cecum and ascending colon sufficiently and observe them in a distant view, because the length of the second observation was determined to be precisely 30 sec. For the second observation, LCI was performed for the first 65 patients and WLI for the next 65. Adenoma and SSA/P detection rate (ASDR) in the second observation were examined in both groups. According to a pilot study, the sample size was estimated 65.

Results: In the first observation, ASDR were 30.7% in the LCI group and 32.2% in the WLI group (p = 0.85). For the second observation, 13 polyps were detected in the LCI group and 5 polyps in the WLI group (p = 0.04). Additionally, ASDR for the second observation were 18.5% and 6.1%, respectively (p = 0.03). There were no significant differences between the LCI and WLI groups with respect to morphology (ratio of polypoid) (38.5% versus 60.0%, p = 0.52) and histology (ratio of adenoma) (92.3% versus 100.0%, p = 0.91). Total adenoma and SSA/P number were 48 in the LCI group and 36 in the WLI group (p = 0.02).

Conclusion: The 30 seconds additional observation with LCI improved the detection of adenoma and SSA/P in the right-sided colon.

1 Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan
2 Department of Gastroenterology, Fukuchiyama City Hospital, Kyoto, Japan
3 Department of Gastroenterology, Osaka General Hospital of West Japan Railway Company, Osaka, Japan
4 Department of Surgical Pathology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan

Ono S¹, Kato M¹, Tsuda M¹, Miyamoto S¹, Abiko S¹, Shimizu Y¹, Sakamoto N¹

Digestion. 2018 Jul 25;98(4):222-230. doi: 10.1159/000489454

Background and aims: Recently, there have been some reports that image-enhanced endoscopy may improve detection of gastric intestinal metaplasia (GIM). Our aim was to determine the usefulness of linked color imaging (LCI) for detection of GIM.

Methods: In prospectively recruited patients, the whole antrum was observed by white light imaging (WLI) followed by LCI. When a whitish flat elevation (WFE) in WLI and a lavender color sign (LCS) in LCI were detected, target biopsies were performed after LCI. Random biopsies were performed in patients who had neither WFE nor LCS. The primary endpoint was the diagnostic accuracy of GIM per patient in WLI and LCI and the secondary endpoints were that of GIM per biopsy and interobserver agreement.

Results: Data from 128 patients were analyzed and 58 patients (45.3%) had histological GIM in the antrum. The per-patient yields of WLI and LCI to detect GIM were 19.0% (11/58) and 91.4% (53/58) respectively. Diagnostic accuracies of target biopsies for GIM were 23.7% in WLI and 84.2% in LCI. Kappa values among 3 doctors were 0.60 for WFE and 0.78 for LCS respectively.

Conclusion: LCI could be a new diagnostic tool for detecting GIM during routine endoscopy.

1 Division of Endoscopy, Hokkaido University Hospital, Sapporo, Japan