Diagnostic performance of volumetric laser endomicroscopy for Barrett's esophagus dysplasia amongst gastroenterology trainees

Background: Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used in Barrett's esophagus (BE) surveillance. VLE image interpretation is challenged by subtle grayscale image variation across a large amount of data. Training in VLE interpretation is not standardized. This study aims to determine if VLE training can be incorporated into a gastroenterology (GI) fellowship curriculum with the use of a self-directed module. Methods: A standardized, self-directed training module (30 min) was created explaining the background and established VLE criteria for the diagnosis of BE dysplasia. A VLE image dataset was generated from a multicenter VLE database of targeted biopsies. GI trainees were asked to grade each image for the presence or absence of the following criteria (I) increased surface optical frequency domain imaging (OFDI) signal intensity and (II) atypical glands and provide a final diagnosis (dysplastic vs. non-dysplastic). Diagnostic performance was calculated and results compared to VLE expert interpretation using histology as the gold-standard. Results: The dataset included 50 VLE images (10 high-grade dysplasia, 40 non-dysplastic BE). VLE images were reviewed in a randomized and blinded fashion by 5 GI trainees with no prior VLE experience and 5 experienced VLE users. Sensitivity, specificity and accuracy of GI trainees was 83.3% (95% CI: 71.5-91.7%), 59.0% (95% CI: 51.6-66.0%), and 64.8% (95% CI: 58.5-70.7%) compared to 80.0% (95% CI: 67.7-89.2%), 79.5% (95% CI: 73.0-85.0%), and 79.6% (95% CI: 74.1-84.4%) for VLE experts respectively. The difference in specificity and accuracy between the two groups were statistically significant with P<0.001.Conclusions: A brief training session on VLE is inadequate to reach competency in interpretation of VLE by GI trainees. Additional experience is required to accurately interpret VLE images.