Feasibility and efficacy of pH-integrated ultrathin endoscopy for ambulatory gastroesophageal reflux monitoring (with videos).

BACKGROUND

Current techniques for monitoring gastroesophageal reflux are limited to measuring physicochemical parameters. We presented a novel pH-integrated ultrathin endoscope (the EndoMonitor System) for simultaneous acquisition of reflux images and pH data. This preclinical study evaluated the performance of the latest version of the EndoMonitor System.

METHODS

The stability and hydrogen ion selectivity of the pH electrode in the EndoMonitor System were evaluated. Subsequently, six types of reflux events were simulated in an isolated organ (porcine esophagus-stomach). Complete duodenal ligation was used to create porcine gastroesophageal reflux models. The number of reflux episodes and acid exposure time were assessed and compared with the pH-impedance catheter results.

RESULTS

The detection rates for distal acid reflux, distal mixed reflux, and horizontal acid reflux events of the EndoMonitor System were significantly higher than those of the pH-impedance catheter (100% vs 18.6%, 100% vs 32.7%, and 100% vs 49.1%, respectively; all P < 0.001). Furthermore, the EndoMonitor System demonstrated superior detection performance in proximal acid and mixed reflux events compared with the pH-impedance catheter (100% vs 90.9% and 100% vs 88.1%, respectively; both P < 0.05). In vivo reflux monitoring demonstrated statistically higher detection rates of reflux events with the EndoMonitor System in two-thirds of the experimental groups (P < 0.05), with a more remarkable overall detection advantage (100% vs 82.0%; P < 0.001). The acid exposure time measurement results for these two devices were comparable (mean ± standard deviation: 2.62 ± 1.82 vs 2.52 ± 1.74 min; P = 0.161).

CONCLUSIONS

The EndoMonitor System improves the accuracy of identifying reflux events and simplifies the monitoring process. It was also highly operable. This study provided important preclinical experience for clinical trials.