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.