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Background and Aim We aimed to investigate whether linked color imaging (LCI) improves endoscopic visibility of early gastric cancers (EGC) after Helicobacter pylori eradication, which are often difficult to detect, and reduces the miss rate when compared with white‐light imaging (WLI). Methods The visibility study used two images, one each with WLI and LCI, from 84 consecutive EGC after H. pylori eradication. Endoscopic visibility was evaluated using a visibility score and color difference (CD) value. To analyze miss rates, we studied a library of recorded videos using both WLI and LCI for 70 other consecutive patients after H. pylori eradication, among whom 19 had EGC. Endoscopic screening was done using the same protocol to map the entire stomach. Six endoscopists reviewed the videos in a randomized order. Miss rates of EGC were compared among the modalities. Results Mean [(±standard deviation) visibility scores with LCI were significantly higher than those with WLI (3.19 ± 0.84 vs 2.52 ± 0.98, P < 0.001), as were mean CD values (26.3 ± 9.1 vs 13.6 ± 6.3, P < 0.001). Miss rates of the six endoscopists were significantly lower with LCI than with WLI (30.7% vs 64.9%, P < 0.001). Both expert and trainee endoscopists had significantly better results with LCI than with WLI. Conclusions Linked color imaging significantly improved the visibility of EGC after H. pylori eradication compared with WLI using both subjective and objective criteria. Furthermore, LCI significantly reduced miss rates of these lesions compared with WLI.

M-Chromo-LCI is expected to become a useful modality for the accurate diagnosis of gastric lesions.

BACKGROUNDConventionally, the low luminous intensity, low image resolution, and difficulty in operation have been reported with the ultrathin endoscope. However, it has markedly advanced recently. The improvement of the diagnostic ability is expected.AIMTo compare the early gastric cancer diagnostic ability of an ultrathin endoscope loaded with a laser light source and that of the conventional endoscope.METHODSThe target subjects were 375 consecutive patients who underwent endoscopy at our hospital for post-endoscopic submucosal dissection follow-up of gastric cancer from January to August 2018. During endoscopy, the ultrathin endoscope was used in 140 patients (37.3%), and the conventional endoscope was used in 235 patients (62.7%). Patient background was adjusted using the propensity score matching method, and gastric cancer detection ability was evaluated in the two groups.RESULTSThe gastric cancer detection rate was 7.8% in the ultrathin endoscope group and 7.0% in the conventional endoscope group, and the mean intragastric observation time was 4.1 ± 1.7 min in the ultrathin endoscope group and 4.1 ± 1.9 min in the conventional endoscope group, showing no significant differences between the groups. Moreover, the biopsy implementation rate was 31.8% in the ultrathin endoscope group and 41.1% in the conventional endoscope group, and the biopsy prediction rate was 17.9% and 13.2%, respectively, showing no significant differences between the groups.CONCLUSIONThe gastric cancer diagnostic ability of the ultrathin endoscope loaded with a laser light source was comparable to that of the conventional endoscope. The observation time was also comparable. Thus, endoscopy using the ultrathin endoscope loaded with the laser light source would be the first option in screening examinations of gastric cancer due to its low invasion.

Background and study aims  As a newly developed endoscopy technique, linked color imaging (LCI) provides very bright images with enhanced color tones. With the objective of improving the detection rate of gastric mucosal cancers, which are often difficult to detect, we examined the utility of LCI from the viewpoint of visibility. Patients and methods  The current study used 100 consecutive gastric mucosal cancers ≤ 20 mm in diameter. For each lesion, we selected one endoscopic image acquired by white-light imaging (WLI), blue-laser imaging (BLI) -bright, and LCI modes. Four endoscopists interpreted the images; using a previously reported scale, we scored the visibility level on a scale of 1 – 4. Results  The mean (± SD) visibility scores were 2.54 ± 1.10 for WLI, 3.02 ± 1.07 for BLI-bright, and 3.28 ± 0.97 for LCI. The score was significantly higher for BLI-bright compared with WLI ( P  < .001) and again higher for LCI compared with BLI-bright ( P  < .001). For the experts, the scores for BLI-bright and LCI were similar, but both were significantly higher than the score for WLI. For the trainees, there was no significant difference between the WLI and BLI-bright scores, but LCI score was significantly higher than those for WLI and BLI-bright scores. With regard to clinical characteristics, LCI particularly enhanced visibility of normochromic, flat and depressed lesions, which had the lowest visibility scores of all three modalities compared with those of the other lesions. Conclusion  LCI increased visibility and may contribute to early detection of gastric mucosal cancers.