Magnification endoscopy with acetic acid for Barrett's esophagus

Human-Like Artificial Intelligent System for Predicting Invasion Depth of Esophageal Squamous Cell Carcinoma Using Magnifying Narrow-Band Imaging Endoscopy: A Retrospective Multicenter Study

INTRODUCTION

Endoscopic evaluation is crucial for predicting the invasion depth of esophagus squamous cell carcinoma (ESCC) and selecting appropriate treatment strategies. Our study aimed to develop and validate an interpretable artificial intelligence-based invasion depth prediction system (AI-IDPS) for ESCC.

METHODS

We reviewed the PubMed for eligible studies and collected potential visual feature indices associated with invasion depth. Multicenter data comprising 5,119 narrow-band imaging magnifying endoscopy images from 581 patients with ESCC were collected from 4 hospitals between April 2016 and November 2021. Thirteen models for feature extraction and 1 model for feature fitting were developed for AI-IDPS. The efficiency of AI-IDPS was evaluated on 196 images and 33 consecutively collected videos and compared with a pure deep learning model and performance of endoscopists. A crossover study and a questionnaire survey were conducted to investigate the system's impact on endoscopists' understanding of the AI predictions.

RESULTS

AI-IDPS demonstrated the sensitivity, specificity, and accuracy of 85.7%, 86.3%, and 86.2% in image validation and 87.5%, 84%, and 84.9% in consecutively collected videos, respectively, for differentiating SM2-3 lesions. The pure deep learning model showed significantly lower sensitivity, specificity, and accuracy (83.7%, 52.1% and 60.0%, respectively). The endoscopists had significantly improved accuracy (from 79.7% to 84.9% on average, P = 0.03) and comparable sensitivity (from 37.5% to 55.4% on average, P = 0.27) and specificity (from 93.1% to 94.3% on average, P = 0.75) after AI-IDPS assistance.

DISCUSSION

Based on domain knowledge, we developed an interpretable system for predicting ESCC invasion depth. The anthropopathic approach demonstrates the potential to outperform deep learning architecture in practice.

Applications of acetic acid spray combined with narrow band imaging in diagnosis of early gastrointestinal cancers and precancerous lesions

Many new endoscopic techniques have been used for the diagnosis of early gastrointestinal cancers and precancerous lesions, such as magnifying endoscopy, narrow-band imaging (NBI), Fuji intelligent chromoendiscopy, i-scan imaging, confocal laser endomicroscopy, and chromoendoscopy (Lugol's iodine, indigo carmine, methylene blue, acetic acid, and crystal violet). Each technique has its own advantages and disadvantages (e.g., being expensive and prolonged examination duration). Spraying acetic acid onto the mucosal surface can enhance the recognition of mucosal surface architecture, and NBI has the advantage to display the microvascular morphology. Thus, acetic acid spray combined with NBI endoscopy can greatly improve the diagnosis of early gastrointestinal cancers and precancerous lesions. Since this combination has low cost and no adverse reactions, they can be used in primary hospitals without magnification endoscopy.

Acetic acid chromoendoscopy: Improving neoplasia detection in Barrett's esophagus

Barrett’s esophagus (BE) is an important condition given its significant premalignant potential and dismal five-year survival outcomes of advanced esophageal adenocarcinoma. It is therefore suggested that patients with a diagnosis of BE undergo regular surveillance in order to pick up dysplasia at an earlier stage to improve survival. Current “gold-standard” surveillance protocols suggest targeted biopsy of visible lesions followed by four quadrant random biopsies every 2 cm. However, this method of Barrett’s surveillance is fraught with poor endoscopist compliance as the procedures are time consuming and poorly tolerated by patients. There are also significant miss-rates with this technique for the detection of neoplasia as only 13% of early neoplastic lesions appear as visible nodules. Despite improvements in endoscope resolution these problems persist. Chromoendoscopy is an extremely useful adjunct to enhance mucosal visualization and characterization of Barrett’s mucosa. Acetic acid chromoendoscopy (AAC) is a simple, non-proprietary technique that can significantly improve neoplasia detection rates. This topic highlight summarizes the current evidence base behind AAC for the detection of neoplasia in BE and provides an insight into the direction of travel for further research in this area.

Advances in the management of Barrett's esophagus and early esophageal adenocarcinoma

The incidence of esophageal adenocarcinoma (EAC) has markedly increased in the United States over the last few decades. Barrett’s esophagus (BE) is the most significant known risk factor for this malignancy. Theoretically, screening and treating early BE should help prevent EAC but the exact incidence of BE and its progression to EAC is not entirely known and cost-effectiveness studies for Barrett’s screening are lacking. Over the last few years, there have been major advances in our understanding of the epidemiology, pathogenesis and endoscopic management of BE. These developments focus on early recognition of advanced histology and endoscopic treatment of high-grade dysplasia. Advanced resection techniques now enable us to endoscopically treat early esophageal cancer. In this review, we will discuss these recent advances in diagnosis and treatment of Barrett’s esophagus and early esophageal adenocarcinoma.

The role of acetic acid in the management of Barrett's oesophagus

Barrett's oesophagus is of significant importance due to its premalignant potential. Acetic acid chromoendoscopy is a simple technique that can be used with any endoscope system. It has been utilised for the identification of Barrett's intestinal metaplasia; and more importantly, for the localisation of early neoplasia within Barrett's, which is often focal, subtle and very easy to miss by random quadrantic biopsies alone. Acetic acid is routinely utilised in specialised centres and its use is expanding. This article examines the evidence base behind acetic acid chromoendoscopy and looks at where further research needs to be directed.

Magnification endoscopy with acetic acid enhancement and a narrow-band imaging system for pit pattern diagnosis of colorectal neoplasms

BACKGROUND AND GOALS

Pit pattern (PP) analysis of colorectal neoplasms using magnification chromoendoscopy with crystal violet (CV-MCE) is useful for predicting histologic features, but it is time consuming. Capillary pattern analysis by magnification endoscopy with narrow-band imaging (NBIME) is a useful and simpler procedure, but its diagnostic accuracy may be inferior to CV-MCE. NBIME with acetic acid enhancement (A-NBIME) is effective for rapid visualization of gastric mucosal microstructures. We performed a prospective study to compare the diagnostic reliability and feasibility of A-NBIME and CV-MCE in PP diagnosis of colorectal neoplasms.

STUDY

The present study consisted of 3 protocols: Study-1 assessed 56 colorectal lesions photographed with A-NBIME and CV-MCE, and the endoscopic images were reviewed by 3 experts to compare the diagnostic concordance; study-2 assessed 202 colorectal lesions photographed with A-NBIME in 116 consecutive patients and the correlation between PP and histologic findings; study-3 randomly allocated 100 patients with colorectal lesions equally to A-NBIME and CV-MCE, and compared the procedure time and visible ratio of PP.

RESULTS

The κ value for interobserver agreement for A-NBIME and CV-MCE was 0.71 (0.66 to 0.75) and 0.80 (0.75 to 0.85), respectively. Intraobserver agreement between modalities for each reviewer was 0.79 (0.70 to 0.88), 0.80 (0.71 to 0.90), and 0.74 (0.67 to 0.82). Non-neoplastic polyps and massively invasive submucosal adenocarcinomas were statistically related to type II and type VI-H/VN. The procedure time was statistically shorter with A-NBIME than with CV-MCE (31 vs. 81 s), and the visible ratio of PP was equivalent (98.9% vs. 98.3%).

CONCLUSIONS

A-NBIME is comparable with CV-MCE in PP diagnosis of colorectal neoplasms and is a simpler technique.

Red flag imaging techniques in Barrett's esophagus

The key to detection and treatment of early neoplasia in Barrett's esophagus (BE) is thorough and careful inspection of the Barrett's segment. The greatest role for red flag techniques is to help identify neoplastic lesions for targeted biopsy and therapy. High-definition white light endoscopy (HD-WLE) can potentially improve endoscopic imaging of BE compared with standard endoscopy, but little scientific evidence supports this. The addition of autofluorescence imaging to HD-WLE and narrow band imaging increases sensitivity and the false-positive rate without significantly improving overall detection of BE-related neoplasia.

Diagnosis of Early Gastric Cancer by Magnifying Endoscopy with NBI from Viewpoint of Histological Imaging: Mucosal Patterning in terms of White Zone Visibility and Its Relationship to Histology

The diagnosis of early gastric cancer by magnifying endoscopy with NBI is based on two components: microvascular pattern and mucosal pattern. Mucosal patterns are characterized by a whitish edge, which has been named the white zone. Some cancerous areas showing a distinct white zone form clear mucosal patterns, whereas others showing a nondistinct white zone do not form mucosal patterns. The aim of the present study was to clarify the histological differences between these two types of area. In transverse sections of gastric epithelium, the lengths of intervening parts in areas showing a distinct white zone, a nondistinct white zone, and an invisible white zone were measured, and the depths of the crypts in these three types of area were also measured. The intervening parts in areas with a nondistinct or invisible white zone were shorter than those in areas with a distinct white zone (P < 0.05), and the crypts in the former areas were shallower than those in the latter (P < 0.01). Areas in which the intervening part were long and the crypts deep tended to show a distinct white zone, whereas areas with short intervening parts or shallow crypts tended to show a nondistinct or non-visible white zone.

[Endoscopic technique in endobrachyoesophagus diagnosis: Chromoendoscopy and acetic acid]

Screening for complications of neoplastic Barrett's oesophagus requires a tedious blind standardized protocol biopsies quadrant every 1 to 2cm depending on the morphology of the Barrett's epithelium (Protocol of Seattle). To achieve that biopsies targeted to areas suspicious of dysplasia, a method of high sensitivity is required. Chromoendoscopy has been developed in this direction. Acetic acid combined with high resolution endoscopy and zooming represents an aid in the preparation of the oesophageal mucosa for visualization of suspicious anomalies. It is safe, cheap and easy to use. Acetic acid has proven its value in improving the visibility of the pit pattern. Several vital dyes have been tested, including methylene blue, indigo carmine and crystal violet, with mixed results. The FICE(®) and NBI(®), immediate, reversible and attractive virtual chromoendoscopy techniques represent interesting tools for improving sensitivity in screening for Barrett's oesophagus and its complications. Confocal endomicroscopy, which is similar as a "per-endoscopic real time histological examination", seems to be equally a promising technique in detection of Barrett's oesophagus associated neoplasia. But these tools which are capable of improvement so far, have not proved their use on a large population. For this, the systematic biopsy protocol Seattle remains the "gold standard" in monitoring the Barrett's oesophagus.

Endoscopic evaluation and advanced imaging of Barrett's esophagus

Enhanced visualization techniques are available for Barrett's esophagus and have promise in the detection of dysplasia and cancer. Several of these techniques, such as narrow band imaging and chromoendoscopy, are being applied clinically. These techniques will allow the endoscopist to screen the surface of the Barrett's esophagus to detect areas of neoplasia. Once detected, it is hoped that either magnification techniques, such as confocal laser endomicroscopy, or spectroscopic techniques can be of value in allowing in vivo real-time diagnostic capabilities.

Incidence of macroscopically occult neoplasias in Barrett's esophagus: are random biopsies dispensable in the era of advanced endoscopic imaging?

OBJECTIVES

The gold standard for endoscopic surveillance of Barrett's esophagus (BE) includes targeted biopsies (TBs) from abnormalities as well as stepwise four-quadrant biopsies (4QBs) for detection of invisible high-grade intraepithelial neoplasias (HGINs) or early carcinomas (ECs). In a large mixed BE population, we investigated the rate of HGINs/ECs that are macroscopically occult to enhanced visualization with high-resolution endoscopy plus acetic acid chromoendoscopy.

METHODS

From January 2007 to December 2009, 701 consecutive BE patients were enrolled in a prospective study at a tertiary referral center. Of these, 406 patients had a history of HGIN/EC (high-risk group) and 295 patients did not (low-risk group).

RESULTS

In 701 patients, 459 TBs and 5,485 4QBs were obtained. Altogether, 92 patients with 132 lesions containing HGINs/ECs were detected. For the diagnosis of HGINs/ECs, patient-related sensitivity and specificity rates of endoscopic imaging with TBs were 96.7 and 66.5%, with a positive and negative predictive value of 30.4 and 99.3%, respectively. In the high-risk group, 4QBs identified three additional patients (3.3%) with macroscopically occult HGINs/ECs. In the low-risk group, no HGINs/ECs were identified with either biopsy approach.

CONCLUSIONS

Advanced endoscopic imaging identifies the vast majority of BE patients with early neoplasias, and the additive effect of 4QB is minimal. Therefore, in low- and high-risk patients, limiting endoscopic surveillance to guided biopsies is justified in specialized high-volume centers with permanent quality control. However, we do not advocate abandoning 4QB outside this setting.

[Diagnostic and interventional endoscopy in gastroenterology : from high-resolution chips and procedures for endoscopic resection to NOTES]

In the past 10 years endoscopic diagnostics has benefited from technologies such as big chips, high-definition television (HDTV) and narrow band imaging (NBI). Video capsule endoscopy and double balloon enteroscopy have facilitated visualization of the entire small bowel. A number of studies on mucosal Barrett's and gastric cancers could prove that endoscopic mucosal resection (EMR) is oncologically equivalent to surgical resection when certain criteria are respected. However, EMR is less invasive and carries a substantially lower complication risk and mortality compared to surgery. Endoscopic submucosal dissection (ESD) facilitates en bloc resection with thorough histopathologic evaluation of the specimen, e.g. for mucosal lesions in the stomach and rectum. Endosonography (EUS) guided transgastric necrosectomy using a flexible gastroscope has set a milestone in the treatment of infected pancreatic necroses and has replaced open surgery in many centers. Natural orifice transluminal endoscopic surgery (NOTES) uses natural body openings as minimally invasive access to the abdomen and mediastinum. Interventional GI endoscopists and minimally invasive surgeons have profited from these innovations in micromechanics and microelectronics.

The prevalence of and risk factors for Barrett's esophagus in a Korean population: A nationwide multicenter prospective study

OBJECTIVE

The aim of this study was to evaluate the prevalence of Barrett's esophagus (BE) in the general Korean population by evaluating screening esophagogastroduodenoscopy. In addition, the risk factors for BE were identified.

METHOD

An esophagogastroduodenoscopy examination was performed in 25,536 subjects who had upper endoscopy screening from January 2006 to July 2006.

RESULTS

Two hundred and fifteen subjects were confirmed to have BE by pathology, thus the prevalence of BE was calculated to be 0.84%. The endoscopic findings were subdivided into 2 groups: BE without reflux esophagitis (RE), which included 167 (77.7%), and BE with RE, which included 48 (22.3%). The analysis of symptoms showed that only 60.1% of the subjects with BE had reflux symptoms. Chest pain [odds ratio (OR): 1.48, 95% confidence interval (CI): 1.04-2.11] and epigastric soreness (OR: 1.42, 95% CI: 1.05-1.93) were found more frequently in the subjects with BE compared with the normal subjects. The multivariate analysis showed that the risk factors for all subjects with BE were a male sex (OR: 1.82, 95% CI: 1.32-2.50), nonsteroidal anti-inflammatory drug use (OR: 2.02, 95% CI: 1.28-3.20), hiatal hernia (OR: 5.66, 95% CI: 3.70-8.66), and an age > or = 60 compared with an age < 40 (OR: 1.81, 95% CI: 1.07-3.09). There was no significant difference associated with RE.

CONCLUSIONS

The prevalence of BE in Korean patients presenting for a routine health check-up was 0.84%, lower than reported in Western countries. Among the subjects with BE 77.7% did not have endoscopic erosions and there were no reflux symptoms in 39.9%. These results suggest that regular endoscopic screening with a high index of suspicion is necessary for the diagnosis of BE.

Chromoendoscopy

Chromoendoscopy involves the use of stains or dyes during endoscopy to improve the visualization and characterization of the gastrointestinal mucosa. Its main clinical application is the detection of dysplasia or early cancer of the gastrointestinal tract in individuals with pre-malignant conditions or hereditary and environmental factors that predispose them to cancer. The utility of chromoendoscopy has been mostly studied in squamous cell carcinoma of the esophagus, Barrett's esophagus, gastric cancer, colorectal polyps, and chronic ulcerative colitis. Although chromoendoscopy has been shown to be feasible and safe, several limitations have prevented its widespread use in endoscopy. Despite this, chromoendoscopy remains a useful adjunct to standard white light endoscopy in the visualization of mucosal lesions, which may potentially improve tissue diagnosis and impact patient care.

Endoscopic evaluation of esophago-gastro-jejunostomy in rat model of Barrett's esophagus

Endoscopy can be used to monitor the onset of metaplastic transformation and to observe the progression of neoplasia in small animal models of Barrett's esophagus. By avoiding animal sacrifice, the natural history of this disease can be studied in a longitudinal fashion. We aim to characterize the endoscopic features of esophageal mucosa at various stages of the metaplasia-dysplasia-carcinoma sequence in a rat reflux model of Barrett's for comparison with histology. Acid and bile reflux was produced by introducing a side-to-side esophago-gastro-jejunostomy in Sprague-Dawley rats. Endoscopic examination of the distal esophagus was performed in 24 surgically altered and 4 control rats, between weeks 24 and 36 after the operation in 4-week intervals, and all rats were biopsied and sacrificed at 36 weeks. Endoscopic images were classified based on the surface mucosal patterns of the distal esophagus and then compared with histology. The endoscopic appearance was classified as: (i) normal, characterized by a smooth surface; (ii) intestinal metaplasia, defined as elevated plaques/ridges, deep grooves, and thin linear folds; (iii) dysplasia, indicated by coarse folds/grooves, meshlike villi, and foveolar appearance; and (iv) carcinoma, suggested by irregular-shaped mass lesions with ulcerations. The endoscopic criteria for intestinal metaplasia yielded a sensitivity of 100% in comparison with histology. Intestinal metaplasia with high-grade dysplasia was found in two rats and with low-grade dysplasia in three rats. Both focally invasive squamous cell carcinoma and invasive adenocarcinoma were found in one rat. Small animal endoscopy in a rat model of Barrett's esophagus can be used to perform surveillance, classify mucosal patterns, observe the onset of intestinal metaplasia, and monitor the progression of neoplastic transformation, representing a useful tool for studying the natural history of this disease.

The usefulness of chromoendoscopy with methylene blue in Barrett's metaplasia and early esophageal carcinoma

BACKGROUND

Barrett's esophagus is a condition that is premalignant for adenocarcinoma of the esophagus and the esophagogastric junction. Early detection of Barrett's metaplasia and dysplasia is very important to decrease the mortality and morbidity from esophageal adenocarcinoma cancer. This study aimed to evaluate the effectiveness of methylene blue-targeted biopsies in the differential diagnosis of intestinal metaplasia, dysplasia, and superficial esophageal carcinoma.

METHODS

A total of 109 patients (43 women and 66 men; average age, 62.32 +/- 10.61 years; range, 33-82 years) were enrolled for the study. Four groups were designed before endoscopic examinations. The patients for these groups were selected at the conventional endoscopy, and then chromoendoscopy was performed. The esophagus was stained with methylene blue, after which six biopsies were taken from stained and unstained areas.

RESULTS

Conventional and chromoendoscopic assessments were compared with histopathologic examination. The sensitivity of chromoendoscopy for Barrett's epithelium was superior to that of conventional endoscopy (p < 0.05). However, there was no statistical difference between the two methods in the diagnosis of esophagitis or esophageal carcinoma (p > 0.05). Stained biopsies were superior to unstained biopsies in terms of sensitivity for Barrett's epithelium and esophageal carcinoma (p < 0.001).

CONCLUSION

Chromoendoscopy is useful for delineating Barrett's epithelium and for indicating the correct location for securing biopsies where dysplasia or early esophageal cancer is suspected.

Chromoendoscopy and narrow-band imaging compared with high-resolution magnification endoscopy in Barrett's esophagus

BACKGROUND & AIMS

The aim of this study was to compare magnified still images obtained with high-resolution white light endoscopy, indigo carmine chromoendoscopy, acetic acid chromoendoscopy, and narrow-band imaging to determine the best technique for use in Barrett's esophagus.

METHODS

We obtained magnified images from 22 areas with the 4 aforementioned techniques. Seven endoscopists with no specific expertise in Barrett's esophagus or advanced imaging techniques and 5 international experts in this field evaluated these 22 areas for overall image quality, mucosal image quality, and vascular image quality. In addition, the regularity of mucosal and vascular patterns and the presence of abnormal blood vessels were evaluated, and this was correlated with histology.

RESULTS

The interobserver agreement for the 3 features of mucosal morphology with white light images ranged from kappa = 0.51 (95% confidence interval [CI]: 0.46-0.55) to kappa = 0.53 (95% CI: 0.50-0.57) for all observers, from kappa = 0.43 (95% CI: 0.33-0.54) to kappa = 0.53 (95% CI: 0.41-0.64) for experts, and from kappa = 0.51 (95% CI: 0.15-0.33) to kappa = 0.64 (95% CI: 0.58-0.70) for nonexperts. The interobserver agreement in these groups did not improve by adding one of the enhancement techniques. The yield for identifying early neoplasia with white light images was 86% for all observers, 90% for experts, and 84% for nonexperts. The addition of enhancement techniques did not improve the yield neoplasia.

CONCLUSIONS

The addition of indigo carmine chromoendoscopy, acetic acid chromoendoscopy, or narrow-band imaging to white light images did not improve interobserver agreement or yield identifying early neoplasia in Barrett's esophagus.

American Gastroenterological Association (AGA) Institute technology assessment on image-enhanced endoscopy

This document presents the official recommendations of the American Gastroenterological Association (AGA) Institute Technology Assessment on "Image-Enhanced Endoscopy." It was approved by the Clinical Practice and Economics Committee on August 3, 2007, and by the AGA Institute Governing Board September 27, 2007.

Detection and treatment of dysplasia in Barrett's esophagus: a pivotal challenge in translating biophotonics from bench to bedside

Barrett's esophagus (BE) is a condition that poses high risk of developing dysplasia leading to cancer. Detection of dysplasia is a critical element in determining therapy but is extremely challenging, so that standard white-light endoscopy is used only as a means to guide biopsy. Many novel optical techniques have been aimed at this problem, including various forms of improved wide-field white-light (chromoendscopy/magnification and narrow-band) and fluorescence imaging, and "optical biopsy" techniques (diffuse reflectance, elastic light scattering, fluorescence and Raman spectroscopies, confocal microendoscopy, and optical coherence tomography). While promising, either as stand-alone modalities or in combination, to date none has solved this pivotal challenge to the point of clinical adoption. Likewise, minimally invasive treatment of BE patients with dysplasia remains suboptimal, despite recent approval of photodynamic therapy for this indication. This work presents a critique and summary of each of these biophotonic technologies, and discusses the fundamental advantages and limitations of each. The future directions for this field are considered, particularly from the perspective of relying on intrinsic (endogenous) optical signatures compared with the use of exogenous contrast agents.

In vivo optical biopsy of hamster oral cavity with epi-third-harmonic-generation microscopy

The first in vivo optical virtual biopsy based on epi-third-harmonic-generation (THG) microscopy is successfully demonstrated using Syrian hamster oral mucosa as a model system. Without complex physical biopsy procedures, epi-THG microscopy can provide high spatial resolution dynamic images of oral mucosa and sub-mucosa in all three dimensions. The demonstrated intra-vital epi-THG microscopy provide high resolution observation of blood flow in the capillary and could be a promising tool to image angiogenesis, which is an important feature for many human diseases including malignancies. The system setup of epi-THG microscopy can be easily integrated with other nonlinear optical microscopy such as second-harmonic generation and multi-photon fluorescence microscopy by using the same laser system to provide better integrated molecular and structural information for future clinical diagnosis. By adding 6% acetic acid solution on the mucosa, THG contrast on the borders of nuclei was found to be greatly enhanced due to the alterations of their linear and nonlinear THG susceptibilities. With a virtual-transition-based technology without using fluorescence, the optical epi-THG biopsy we demonstrated shows promise for future noninvasive in vivo diseases examinations.