Savarino E, Zentilin P, Savarino V, et al. Ann. N.Y. Acad. Sci. 2013;1300:226-235.

OBJECTIVES: The following paper on functional testing of the pharynx includes commentaries on the use of 24-h pH–impedance testing to identify patients with nonacid reflux and the caveats associated with automatic and visual analysis; the potential diagnostic yield of ambulatory high-resolution manomentry (HRM), particularly in identifying noncardiac chest pain and transient lower esophageal sphincter relaxations; the differential manometric identification of conditions facilitated by using solid swallows, and the advantages of the newly developed ResTech oropharyngeal pH probe in the detection of proximal reflux events.

RESULTS: The accuracy and reproducibility of traditional pH probes in the hypopharynx is less than optimal. Recently, a minimally invasive pH probe (ResTech’s dx-pH device) with some variations from the traditional pH probe was developed to measure reflux in the oropharynx of patients suspected of having extraesophageal symptoms presumed to be related to GERD. In the ResTech probe, the reference and sampling electrodes are in close proximity, which reduces the likelihood of missed events especially when positioned in the hypo- or oropharynx.

The device utilizes a 1.5mmdiameter catheter, a specially designed sensor, and a unique flashing LED light to guide the catheter into proper position in the posterior oropharynx above the upper esophageal sphincter, and records pH values twice every second, rather than once every 4–6 s as in other devices.

CONCLUSION: In conclusion, the new oropharyngeal pH probe has many variations which can be advantageous in the detection of proximal reflux events and in the determination of the individuals who might benefit from medical or surgical antireflux treatment. New studies are needed with bigger study population chosen with more homogeneous diagnostic criteria for LPR to enlighten the value of this new device.