Linked color imaging improves detection of minimal change esophagitis in non-erosive reflux esophagitis patients

Linked color imaging improves the diagnostic accuracy of eosinophilic esophagitis

Objectives

To assess the usefulness of linked color imaging (LCI), a recently developed image‐enhanced endoscopy technique, in the endoscopic diagnosis of eosinophilic esophagitis (EoE).

Methods

Thirty white light images (WLIs) and 30 WLI+LCI images collected from patients with and without EoE were randomly and blindly reviewed by 10 endoscopists, including four experts (Exs) and six non‐Exs. Edema, ring, exudate furrows, and strictures were rated on the adjusted EoE endoscopic reference score; the diagnosis of EoE was assessed. Using the kappa value, inter‐ and intra‐observer agreements were analyzed among endoscopists.

Results

WLI+LCI images had a higher diagnostic accuracy for EoE than WLIs (0.85 vs. 0.70, respectively), especially in non‐Exs or endoscopists with no experience with EoE patients. Inter‐observer agreement for WLI+LCI images statistically surpassed WLIs for furrows (kappa, 0.73 vs. 0.67, respectively; p = 0.0013), stricture (kappa, 0.51 vs. 0.39, respectively; p = 0.0072), and diagnosis (kappa, 0.67 vs. 0.57, respectively; p < 0.0001) of EoE. The increase in inter‐observer agreement in WLI+LCI images allowed for a reduction in the differences between the Exs and non‐Ex endoscopists. Intra‐observer agreement for WLI+LCI images surpassed WLIs for a ring (kappa, 0.62 vs. 0.43, p = 0.0052), and a similar trend was found in exudates, furrows, and diagnosis irrespective of the Exs or non‐Exs.

Conclusions

LCI can contribute to the improvement of the endoscopic diagnosis for EoE, with “moderate” to “substantial” consistency, by enhancing the visibility of abnormal findings, leading to reduced diagnostic disparities among endoscopists.

Usefulness of Endoscopy for the Detection and Diagnosis of Primary Esophageal Motility Disorders and Diseases Relating to Abnormal Esophageal Motility

Esophagogastroduodenoscopy (EGD) is performed to rule out organic diseases in the diagnosis of esophageal motility disorders (EMDs). Abnormal endoscopic findings can be observed during EGD, which indicate the presence of EMDs. Several endoscopic findings at both the esophagogastric junction and esophageal body that are related to EMDs have been reported. Gastroesophageal reflux disease (GERD) and eosinophilic esophagitis (EoE) could be detected during EGD, and these diseases are often associated with abnormal esophageal motility. Image-enhanced endoscopy (IEE) could improve the detection of these diseases during EGD. Although no report has been published previously on the potential usefulness of IEE in the endoscopic diagnosis of EMDs, IEE can be used to detect disorders that can be associated with abnormal esophageal motility.

Endoscopic Diagnosis of Eosinophilic Esophagitis: Basics and Recent Advances

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated inflammatory disease, characterized by esophageal dysfunction and intense eosinophil infiltration localized in the esophagus. In recent decades, EoE has become a growing concern as a major cause of dysphagia and food impaction in adolescents and adults. EoE is a clinicopathological disease for which the histological demonstration of esophageal eosinophilia is essential for diagnosis. Therefore, the recognition of the characteristic endoscopic features with subsequent biopsy are critical for early definitive diagnosis and treatment, in order to prevent complications. Accumulating reports have revealed that EoE has several non-specific characteristic endoscopic findings, such as rings, furrows, white exudates, stricture/narrowing, edema, and crepe-paper esophagus. These findings were recently unified under the EoE endoscopic reference score (EREFS), which has been widely used as an objective, standard measurement for endoscopic EoE assessment. However, the diagnostic consistency of those findings among endoscopists is still inadequate, leading to underdiagnosis or misdiagnosis. Some endoscopic findings suggestive of EoE, such as multiple polypoid lesions, caterpillar sign, ankylosaurus back sign, and tug sign/pull sign, will aid the diagnosis. In addition, image-enhanced endoscopy represented by narrow band imaging, endocytoscopy, and artificial intelligence are expected to render endoscopic diagnosis more efficient and less invasive. This review focuses on suggestions for endoscopic assessment and biopsy, including recent advances in optical technology which may improve the diagnosis of EoE.

Diagnostic accuracy of linked colour imaging versus white light imaging for early gastric cancers: a prospective, multicentre, randomized controlled trial study

BACKGROUND

Linked colour imaging (LCI) is a novel new image-enhanced endoscopy (IEE) technology that produces bright and vivid images. The aim of this study was to assess the ability of LCI to improve the diagnostic accuracy of early gastric cancer (EGC) relative to white light imaging (WLI).

MATERIALS AND METHODS

We performed this study on patients undergoing screening endoscopy from 12 medical institutions in China. Patients were randomly assigned to receive WLI followed by LCI or LCI followed by WLI. The primary outcome was to compared the diagnostic accuracy between LCI and WLI for EGC/high-grade intraepithelial neoplasms. Secondary outcomes included the numbers of suspicious lesions, neoplastic lesions and examination time by using LCI detected versus using WLI.

RESULTS

A total of 1924 patients were randomly selected, and 1828 were included in the analysis. The diagnostic accuracy for EGC, which was 78.8% by using LCI and 68.4% by using WLI (p < .0001). More suspicious lesions were detected by LCI than by WLI (n = 1235 vs. 1036, p = .031), especially among differentiated EGC (p = .013). LCI greatly shortened the examination time compared with WLI (p = .019).

CONCLUSIONS

LCI has better accuracy and shorter examination time in diagnosing EGC than WLI (Clinical trial registration: NCT03092414).Key messagesCompared with white light imaging (WLI), the diagnostic accuracy, sensitivity and specificity increased by using LCI.More lesions were detected by LCI alone than by WLI alone, especially among differentiated EGC.LCI may be used as a screening tool for routine clinical observation.

Advanced Endoscopy for Benign Esophageal Disease: A Review Focused on Non-Erosive Reflux Disease and Eosinophilic Esophagitis

Advanced endoscopy (AVE) techniques include image-enhanced endoscopy methods, such as narrow-band imaging (NBI), and types of microscopic endoscopy, such as endocytoscopy. In the esophagus, AVE first showed diagnostic utility in the diagnosis of superficial esophageal cancer and was then applied to inflammatory disease. This review focuses on non-erosive reflux disease (NERD) and eosinophilic esophagitis (EoE), which sometimes show no abnormal findings on standard white light endoscopy alone. Studies have demonstrated that advanced endoscopy, including NBI magnification endoscopy and endocytoscopy, improved the diagnostic performance of white-light endoscopy alone for NERD and EoE. In this review, we explain why advanced endoscopy is needed for the diagnosis of these esophageal inflammatory diseases, summarize the study results, and discuss future perspectives.

Evaluation of Minimal Change Lesions Using Linked Color Imaging in Patients With Nonerosive Reflux Esophagitis

BACKGROUND AND AIMS

High prevalence of minimal change lesion (MCL) in nonerosive reflux esophagitis (NERD) patients is commonly recognized by many endoscopists. However, it is difficult to detect MCL with conventional white-light imaging (WLI) endoscopy. Linked color imaging (LCI), a novel image-enhanced endoscopy technology with strong, unique color enhancement, is used for easy recognition of early gastric cancer and detection of Helicobacter pylori infection. The aim of the study was to compare the efficacy of LCI and WLI endoscopy in evaluating MCL in patients with NER.

MATERIALS AND METHODS

Forty-one patients with NERD and 38 subjects with nongastroesophageal reflux disease (non-GERD) were recruited in this study between August 2017 and July 2018. During upper gastrointestinal endoscopy, the distal 5 cm of the esophageal mucosal morphology at the squamocolumnar junction was visualized using WLI followed by LCI. MCL was defined as areas of erythema, blurring of the Z-line, friability, decreased vascularity, white turbid discoloration, and edema or accentuation of the mucosal folds. Three experienced endoscopists evaluated the color patterns for MCL on WLI images and on WLI combined with LCI images in both groups. A biopsy was taken 2 cm above the esophagogastric junction. Histologic slides were scored by a pathologist in a blinded manner.

RESULTS

The proportion of MCL was higher in the patients with NERD (70.7%, 29/41) than in patients with non-GERD (39.5%, 15/38) using WLI combined with LCI. In 12 patients with NERD, both WLI and LCI showed normal mucosa. The MCL detection rate was significantly higher when using WLI combined with LCI than when using WLI (70.7% vs. 51.2%, P=0.039) in patients with NERD. The histopathologic score of MCL (+) was significantly higher than that of MCL (-) patients in both the NERD group (4.59±0.32 vs. 2.36±0.34, P<0.01) and the non-GERD group (3.47±0.50 vs. 2.00±0.28, P<0.01). The intraobserver reproducibility levels and interobserver agreement were better with LCI than with WLI alone.

CONCLUSIONS

Frequency of MCL was higher in patients with NERD than in those with non-GERD. MCL can be identified by using WLI combined with LCI in patients with NERD. By enhancing endoscopic images, LCI is more sensitive in detecting MCL compared with WLI.

The role of endoscopy in the management of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common disease that may cause a huge economic burden. Endoscopy is performed not only to rule out other organic diseases but also to diagnose reflux esophagitis or Barrett's esophagus. Non‐erosive GERD (non‐erosive reflux disease [NERD]) is called endoscopy‐negative GERD; however, GERD‐related findings could be obtained through histological assessment, image‐enhanced endoscopy, and new endoscopic modalities in patients with NERD. Moreover, endoscopy is useful to stratify the risk for the development of GERD. In addition, endoscopic treatments have been developed. These techniques could significantly improve patients’ quality of life as well as symptoms.

The role of advanced endoscopy in the management of inflammatory digestive diseases (upper gastrointestinal tract)

The Japan Gastroenterological Endoscopy Society held four serial symposia between 2019 and 2020 on the state-of-the-art of issues related to upper GI inflammatory diseases. This review discusses some of the topics addressed in these symposia. The papers regarding nonerosive reflux disease, recent improvements in intraesophageal pH-impedance monitoring and endoscopic diagnosis using image-enhanced endoscopy have been published. Many publications have addressed its usefulness in endoscopic treatment of gastroesophageal reflux disease such as anti-reflux mucosectomy. In the management of eosinophilic esophagitis, since the symptoms are subjective, objective indicators have been sought, and ultrasonography and high-resolution manometry may be useful tools for evaluation. The natural course of this condition, especially of asymptomatic cases, is not well clarified. Some newly developed anti-acid or anti-inflammatory medicines are now under investigation. With regard to autoimmune gastritis, because of widespread medical examinations, diagnosis of asymptomatic cases has been increasing. Recently, its endoscopic characteristics have become clear and the natural history of these conditions is being elucidated. The Kyoto Classification of Gastritis has been reported to be useful not only for Helicobacter pylori diagnosis but also for identification of risks of gastric cancer. Its usefulness is now recognized in Asia and Europe.

Application of linked color imaging in the diagnosis of early gastrointestinal neoplasms and precancerous lesions: a review

INTRODUCTION

Minimally invasive endoscopic resection is often effective in the management of early gastrointestinal tumors. However, advanced and more effective methods of endoscopic examination are required to improve the rate of diagnosing early gastrointestinal tumors.

DISCUSSION

The development of dye-based image-enhanced endoscopy (d-IEE) and equipment-based image-enhanced endoscopy (e-IEE) has helped improve the diagnostic rate of early gastrointestinal tumor using endoscopy. In some special cases, these methods are still not accurate in diagnosing lesions. On the basis of these e-IEEs, a new endoscopic technique, linked color imaging (LCI), that combines a specific short wavelength narrow band of light with white light, has been developed.

CONCLUSION

In this article, we summarized the characteristics of LCI and the development of research regarding digestive tract examination.

PLAIN LANGUAGE SUMMARY

Application of linked color imaging in early gastrointestinal neoplasms At present, the complete diagnosis of early gastrointestinal tumors and precancerous lesions can be made by gastrointestinal endoscopy. With the improvement of therapeutic instruments and operators' experience, endoscopic therapy can often achieve significant effect in the treatment of early gastrointestinal tumors. The development and spread of equipment-based image-enhanced endoscopy (e-IEE) mode has helped improve the diagnosis rate of early gastrointestinal tumors under endoscopy. However, in some special cases, these methods are still not accurate for the diagnosis of lesions. On the basis of these E-IEEs, a new endoscopic technique, linked color imaging (LCI), has been developed, which combines a specific short wavelength narrow band of light with white light. LCI can significantly improve the diagnostic rate of all types of gastrointestinal mucosal lesions. Tumor lesions and inflammatory lesions can be distinguished by observing the mucosal microvascular structure and color difference. LCI helps detect early gastrointestinal mucosal lesions by taking advantage of the differences in light absorption of different wavelengths and contrast of enhanced colors in the later stage.

Clinical usefulness of linked color imaging for evaluation of endoscopic activity and prediction of relapse in ulcerative colitis

PURPOSE

In the treatment of ulcerative colitis (UC), accurate evaluation of UC activity is important to achieve mucosal healing. We sought to investigate the clinical utility of linked color imaging (LCI) for the evaluation of endoscopic activity and prediction of relapse in UC patients.

METHODS

We enrolled 72 consecutive UC patients in remission who underwent colonoscopy at our institution between September 2016 and October 2018. The relationship between the presence of redness in white light imaging (WLI) and LCI and histopathological inflammation (Geboes score: GS) at 238 biopsy sites was examined. We also assessed the presence or absence of planar redness in the entire rectum as ± and classified the patients into three groups according to the combination of WLI/LCI: A: WLI-/LCI-, B: WLI-/LCI+, and C: WLI+/LCI+. The relationship between WLI/LCI classification and relapse in 64 patients followed up for more than 12 months from initial colonoscopy was assessed and compared to the Mayo endoscopic subscore (MES).

RESULTS

A GS of 0 or 1 accounted for 89% of WLI/LCI non-redness sites, while a GS of 2 or 3 accounted for 42% of WLI non-redness/LCI redness sites. LCI findings were significantly correlated with GS. During follow-up, 10 patients in group C and four patients in group B relapsed, but none in group A. Non-relapse rates were significantly correlated with WLI/LCI classification, but not with MES.

CONCLUSION

LCI is a useful modality for accurate assessment of endoscopic activity and prediction of relapse in UC by detecting mild inflammation unrecognizable by WLI.

Usefulness of linked color imaging in the early detection of superficial esophageal squamous cell carcinomas

BACKGROUND AND AIMS

Linked color imaging (LCI) improved the visibility of gastric cancer and colorectal flat lesions. This study aimed to investigate the usefulness of LCI in detecting superficial esophageal squamous cell carcinomas (SESCC).

METHODS

We enrolled 37 consecutive SESCC patients (46 SESCCs) diagnosed using LCI and blue laser imaging bright mode (BLI-BRT) and treated in Hiroshima University Hospital between April 2018 and November 2018. Eight professional endoscopists compared images obtained on non-magnifying BLI-BRT and LCI versus conventional white light imaging (WLI). Identification and boundary diagnosis of SESCC with LCI and BLI-BRT were compared with WLI. Changes in lesion visibility were clarified. Interobserver agreement was assessed. Clinicopathological features of lesion that influence visibility with LCI were assessed.

RESULTS

In LCI, 37% (17/46) of cases had improved visibility and 63% (29/46) had unchanged visibility (interobserver agreement = 0.74). Among cases with multiple lugol voiding lesions (LVLs), ΔE between the lesion and background mucosa was significantly higher in LCI than in WLI (20.8 ± 7.9 vs 9.2 ± 6.1, P < 0.05). No significant differences were found in tumor size, morphological type, color, depth, and smoking or drinking history. However, multiple LVLs were significantly higher among cases with improved versus unchanged visibility. On BLI-BRT, 39% (18/46) of cases had improved visibility and 61% (28/46) had unchanged visibility (interobserver agreement = 0.60).

CONCLUSION

Almost the same as BLI-BRT, LCI improves SESCC visibility compared with WLI. This is useful for cases with multiple LVLs. In cases without background coloration (BGC), LCI may make SESCC more visible than BLI-BRT.

Linked color imaging improves visibility of reflux esophagitis

Background

With more prevalent gastroesophageal reflux disease comes increased cases of Barrett's esophagus and esophageal adenocarcinoma. Image-enhanced endoscopy using linked-color imaging (LCI) differentiates between mucosal colors. We compared LCI, white light imaging (WLI), and blue LASER imaging (BLI) in diagnosing reflux esophagitis (RE).

Methods

Consecutive RE patients (modified Los Angeles [LA] classification system) who underwent esophagogastroduodenoscopy using WLI, LCI, and BLI between April 2017 and March 2019 were selected retrospectively. Ten endoscopists compared WLI with LCI or BLI using 142 images from 142 patients. Visibility changes were scored by endoscopists as follows: 5, improved; 4, somewhat improved; 3, equivalent; 2, somewhat decreased; and 1, decreased. For total scores, 40 points was considered improved visibility, 21–39 points was comparable to white light, and < 20 points equaled decreased visibility. Inter- and intra-rater reliabilities (Intra-class Correlation Coefficient [ICC]) were also evaluated. Images showing color differences (ΔE*) and L* a* b* color values in RE and adjacent esophageal mucosae were assessed using CIELAB, a color space system.

Results

The mean age of patients was 67.1 years (range: 27–89; 63 males, 79 females). RE LA grades observed included 52 M, 52 A, 24 B, 11 C, and 3 D. Compared with WLI, all RE cases showed improved visibility: 28.2% (40/142), LA grade M: 19.2% (10/52), LA grade A: 34.6% (18/52), LA grade B: 37.5% (9/24), LA grade C: 27.3% (3/11), and LA grade D: 0% (0/3) in LCI, and for all RE cases: 0% in BLI. LCI was not associated with decreased visibility. The LCI inter-rater reliability was “moderate” for LA grade M and “substantial” for erosive RE. The LCI intra-rater reliability was “moderate–substantial” for trainees and experts. Color differences were WLI: 12.3, LCI: 22.7 in LA grade M; and WLI: 18.2, LCI: 31.9 in erosive RE (P < 0.001 for WLI vs. LCI).

Conclusion

LCI versus WLI and BLI led to improved visibility for RE after subjective and objective evaluations. Visibility and the ICC for minimal change esophagitis were lower than for erosive RE for LCI. With LCI, RE images contrasting better with the surrounding esophageal mucosa were more clearly viewed.