A study on the diagnosis of minimal endoscopic lesions in nonerosive reflux esophagitis using computed virtual chromoendoscopy (FICE)

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.

Advanced Endoscopic Imaging and Interventions in GERD: An Update and Future Directions

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered in primary care and gastroenterology clinics. Most cases of GERD can be diagnosed based on clinical presentation and risk factors; however, some patients present with atypical symptoms, which can make diagnosis difficult. An esophagogastroduodenoscopy can be used to assist in diagnosis of GERD, though only half of these patients have visible endoscopic findings on standard white light endoscopy. This led to the development of new advanced endoscopic techniques that enhanced the diagnosis of GERD and related complications like squamous cell dysplasia, Barrett's esophagus, and early esophageal adenocarcinoma. This is conducted by improved detection of subtle irregularities in the mucosa and vascular structures through optical biopsies in real-time. Management of GERD includes lifestyle modifications, pharmacological therapy, endoscopic and surgical intervention. Minimally invasive endoscopic intervention can be an option in selected patients with small hiatal hernia and without complications of GERD. These endoscopic interventions include endoscopic fundoplication, endoscopic mucosal resection techniques, ablative techniques, creating mechanical barriers, and suturing and stapling devices. As these new advanced endoscopic techniques are emerging, data surrounding the indications, advantages and disadvantages of these techniques need a thorough understanding.

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.

Detection of minimal mucosal esophageal lesions in non-erosive gastroesophageal reflux disease using optical enhancement plus optical magnification

Background and study aims  The aim of this study was to evaluate the diagnostic yield of endoscopy using optical enhancement (OE system) with optical magnification to predict reflux in non-erosive reflux disease (NERD) patients. Patients and methods  A prospective, non-randomized, single-blind study was performed from September 2015 to January 2016. Participants suffered from gastroesophageal reflux disease (GERD) symptoms and were assigned to the NERD group or the non-reflux disease control group based on endoscopic findings and a 24-hour pH-impedance-monitoring test. Endoscopy using the OE system with optical magnification was performed in all patients to detect minimal mucosal esophageal lesions (MMEL), specifically abnormalities in the numbers, dilation, and tortuosity of intrapapillary capillary loops (IPCLs). Biopsies were obtained from each esophageal segment, and diagnoses from images were compared to diagnoses of reflux and inflammation using 24-hour pH-impedance monitoring and histology, respectively. Results  Fifty-seven patients were included (36 in the NERD group, 21 in the control group). IPCLs were observed in 94.4 % of cases in the NERD group and 38 % of cases in the control group ( P  < 0.05). There were significant differences in IPCL abnormalities between groups that were associated with histologically identified inflammation. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 94.4 %, 61.9 %, 80.9 %, 86.6 %, and 82.4 %, respectively. The 24-hour pH-impedance-monitoring test was used as the gold standard. The Kappa interobserver and intraobserver values were 0.85 and 0.90, respectively. Conclusion  The OE system with optical magnification can detect MMEL and predict NERD with high sensitivity, accuracy, and interobserver and intraobserver agreement. Presence of IPCLs highly correlates with histologically identified inflammation.

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

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 (Clinical trial registration number: NCT03068572).

i-Scan detection of minimal change esophagitis in dyspeptic patients with or without Gastroesophageal Reflux disease

Background

The association of minimal change esophagitis (MCE) with GERD is controversial. i-Scan endoscopy (SE) provides high resolution and modulation of images that may improve minimal change lesion (MCL) detection. We aimed to assess the efficacy of SE in detecting MCL in dyspeptic patients with GERD compared with patients without GERD by GerdQ or by endoscopy with 24-h pH monitoring (PHM) and in normal volunteers.

Methods

This is a cohort study conducted at a tertiary center. All dyspeptic patients were prospectively recruited. All patients completed a validated Thai version of GerdQ and then underwent endoscopy. Forty normal volunteers as a control group were recruited for endoscopy. The distal esophagus was examined by high definition endoscopy and SE sequentially. All had PHM done. GERD was diagnosed by Los Angeles classification A-D and/or by a positive PHM. MCE was diagnosed when MCL or combination of MCL was present.

Results

Of 174 patients, 144 completed the study protocol. After the exclusion of 6 patients, 138 remained for analysis. Overlapping GERD symptoms were found in 44.2 % and 26.8 % had confirmed GERD. Group A was comprised of 61 patients with a positive GerdQ and 77 patients in group B had a negative GerdQ. Twenty-four in group A, 28 in group B and 7 in the control group had MCE that was not significantly different. MCE in GERD was significantly higher (51.45 %) than in non-GERD (32.7 %) (p = 0.047) and in the control group (20.58 %) (p = 0.007). The sensitivity, specificity, positive predictive value, and negative predictive value of SE were 51.35 %, 67.33 %, 36.54 % and 79.06 %, respectively.

Conclusion

In dyspeptic patients, SE detected more MCE in GERD than in non-GERD patients and in the control group.

Trial registration

ClinicalTrials.gov number NCT01742377

High-definition endoscopy with iScan and Lugol's solution for the detection of inflammation in patients with nonerosive reflux disease: histologic evaluation in comparison with a control group

Nonerosive reflux disease (NERD) is commonly diagnosed in patients with symptoms of reflux. The aim of the present study was to determine whether high-definition endoscopy (HD) plus equipped with the iScan function or chromoendoscopy with Lugol's solution might permit the differentiation of NERD patients from those without reflux symptoms, proven by targeted biopsies of endoscopic lesions. A total of 100 patients without regular intake of proton pump inhibitors and with a normal conventional upper endoscopy were prospectively divided into NERD patients and controls. A second upper endoscopy was performed using HD+ with additional iScan function and then Lugol's solution was applied. Biopsy specimens were taken from the gastroesophageal junction in all patients. A total of 65 patients with reflux symptoms and 27 controls were included. HD(+) endoscopy with iScan revealed subtle mucosal breaks in 52 patients; the subsequent biopsies confirmed esophagitis in all cases. After Lugol's solution, 58 patients showed mucosal breaks. Sensitivity for the iScan procedure was 82.5%, whereas that for Lugol's solution was 92.06%. Excellent positive predictive values of 100% and 98.3%, respectively, were noted. The present study suggests that the majority of patients with NERD and typical symptoms of reflux disease can be identified by iScan or Lugol's chromoendoscopy as minimal erosive reflux disease (ERD) patients.

Present and future status of flexible spectral imaging color enhancement and blue laser imaging technology

The usefulness of flexible spectral imaging color enhancement (FICE) has been reported for evaluating the esophagus, stomach, and small and large intestine. Higher contrast is shown between cancer and the surrounding mucosa in the esophagus and stomach and may facilitate the detection of gastric cancers missed by white light imaging alone. The surface patterns of gastric mucosa are clearly visualized in non-malignant areas but are irregular and blurred in malignant areas, leading to clear demarcation. Capsule endoscopy with FICE detects angiodysplasia and erosions of the small intestine. The surface and vascular pattern with FICE is useful for the differential diagnosis of colorectal polyps. However, FICE remains somewhat poor at visualizing mucosal microvasculature on a tumor surface. Narrow-band imaging (NBI) is dark in observing whole gastric mucosa and poor at visualizing mucosal microstructure. Blue laser imaging (BLI) has the potential to resolve these limitations. Narrow-band laser light combined with white light shows irregular microvessels on both differentiated and undifferentiated gastric cancer similar to those using NBI. In addition, irregular surface patterns including minute white zones are clearly seen on the uneven surface of differentiated lesions, resulting in exclusion of undifferentiated lesions. Using both distant and close-up views, a high contrast between green intestinal metaplasia and brown gastric cancer may lead to early detection of gastric cancers and determination of a demarcation line. BLI produces high-contrast images in esophageal cancer with clear vision of intrapapillary capillary loops and also predicts the histopathological diagnosis and depth of invasion in colorectal neoplasms.