Background: In contrast to standard video endoscopy, magnifying endoscopy after local acetic acid application enables recognition of mucosal surface architecture.
Objective: To investigate the diagnostic yield of magnifying endoscopy with acetic acid-targeted biopsies compared to random, 4-quadrant biopsies.
Design: Prospective randomized trial (ratio 1:1) with crossover design.
Setting: Two referral hospitals in Germany.
Patients: Thirty-one patients with Barrett's esophagus or visible columnar-lined lower esophagus.
Interventions: Patients were randomized to undergo either standard video endoscopy with 4-quadrant biopsies or magnifying endoscopy in conjunction with acetic acid application. All patients were re-examined 14 days after the initial endoscopy with the corresponding procedure.
Main outcome measurements: Primary outcome analysis (per protocol and per biopsy) was the histological proof of Barrett's epithelium. Secondary outcome analysis was the correlation between the surface architecture and the presence of Barrett's epithelium and the needed number of biopsies to confirm Barrett's epithelium for the 2 different procedures.
Results: Magnifying endoscopy enabled the prediction of Barrett's epithelium with a sensitivity of 100% and a specificity of 66%, respectively (accuracy 83.8%). Acetic acid-guided biopsies obtained a significantly higher percentage of tissues containing SCE (78%; 188/241) compared to random biopsies (57%; 159/280).
Limitations: No data on the diagnosis of Barrett's dysplasia.
Conclusion: Magnifying endoscopy with acetic acid-guided biopsies is superior to standard video endoscopy with random biopsies, and the number of biopsies needed to confirm Barrett's epithelium is half as much when compared to random biopsies.