Virtual chromoendoscopy by using optical enhancement improves the detection of Barrett’s esophagus–associated neoplasia

Abstract

Background and Aims The Seattle protocol for endoscopic Barrett's esophagus surveillance samples a small proportion of the mucosal surface area-risking a potentially high miss rate of early neoplastic lesions. We assess if the new iScan Optical Enhancement system (OE, Pentax) improves the detection of early BE associated neoplasia compared with high definition white light endoscopy (HD-WLE) in both expert and trainee endoscopists to target sampling of suspicious areas. Such a system may both improve early neoplasia detection and reduce the need for random biopsies. Methods 41 patients undergoing endoscopic BE surveillance from Jan 2016-Nov 2017 were recruited from 3 international referral centers. Matched still images in both HD-WLE (n=130) and iScan OE (n=132) were obtained from endoscopic examinations. Two experts, unblinded to the videos and histology, delineated known neoplasia, forming a consensus criterion standard. 7 expert and 7 trainee endoscopists marked one position per image where they would expect a target biopsy to identify dysplastic tissue. The same expert panel then reviewed magnification images and using a previously validated classification system attempted to classify mucosa as dysplastic or non-dysplastic based on the mucosal and vascular patterns observed on magnification endoscopy. Diagnostic accuracy, sensitivity, specificity, NPV, and PPV were calculated. Improvements in dysplasia detection in HD-WLE vs OE and interobserver agreement (IA) were assessed by multilevel logistic regression analysis and Krippendorff's alpha, respectively. Improvements in diagnostic performance were expressed as an odds ratio between the odds of an improvement in OE, compared with the odds of an improvement in WLE Results

ASGE guideline on screening and surveillance of Barrett’s esophagus

“…The panel did not make a specific recommendation for the type of VC to be used and acknowledged recent data demonstrating increased dysplasia detection using technologies such as the i-Scan Optical Enhancement system. 82 For dye-based CE, the panel made no specific recommendation for the type of dye, but based on available data, acetic acid is the only dye-based CE technique that meets the ASGE PIVI thresholds. 73 Acetic acid enhances mucosal surface patterns by contrast staining.…”

Electronic chromo-endoscopy: technical details and a clinical perspective

“…A further modification of the iSCAN system by optical enhancement (OE) uses both pre and post processing images which can improve dysplasia detection rate without the addition of ACA, thus reducing procedure time (32). as shown in study by Everson et al, which also showed that prediction of histology was better with iSCAN OE compared to HD-WLE by both expert and trainee endoscopists (33).…”

Revising the European Society of Gastrointestinal Endoscopy (ESGE) research priorities: a research progress update

“…Guidelines have different positions on the use of AEI. Since the publication of the previous ESGE priorities, 17 studies examining NBI, blue-light imaging (BLI), i-scan, and chromoendoscopy with acetic acid and Lugol's iodine have been published and were analyzed, of which nine were prospective and eight retrospective [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55]. An additional 19 studies were found on less common techniques including endomicroscopy and the application of computer-assisted diagnosis.…”