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Updated: Jul 28, 2026

Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Successful oesophageal pH monitoring with a catheter-free system
E M Ward1, K R Devault, E P Bouras
1Division of Gastroenterology and Hepatology, Mayo Clinic, Jacksonville, FL 32224, USA.
Background:
Traditional catheter-based oesophageal pH testing is limited by patient discomfort and the tendency for patients to alter their diet and activities during the study. A catheter-free pH monitoring system (Bravo) designed to avoid these problems has recently become available, but the advantages and limitations of this device have not been fully explored.
Aim:
To report our initial experience with this new technology.
Methods:
The records of consecutive patients undergoing Bravo pH monitoring were reviewed. The squamo-columnar junction was localized endoscopically and the pH capsule was placed 6 cm above this junction. All patients were re-endoscoped immediately following placement to document mucosal attachment. Patients were monitored for 24-48 h and then returned the radiotelemetry recording device. Data were subsequently downloaded to a personal computer.
Results:
Sixty studies were performed over an 11-month period. In seven of the 60 (12%), the probe did not attach properly, but in six of these a replacement probe was prepared and deployed without difficulty. In one case, the probe could not be attached after two attempts and the procedure was abandoned. During one procedure, the probe was attached to the mucosa at a point 9 cm from the squamo-columnar junction, but a positive test result was obtained. In two cases, the data were not initially retrievable from the recorder, but in one case the manufacturer was able to retrieve the data overnight. Finally, two patients were away from the data recorder for extended periods, resulting in a loss of data, in two cases, but there was sufficient information for interpretation in both studies. Therefore, adequate diagnostic data were obtained in 58 of the 60 (97%) studies.
Conclusions:
Catheter-free pH testing is a major advance in patient convenience and comfort. The technical difficulties associated with this new technology are minimal and appear to be no more frequent than those seen with catheter-based systems.
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