Where is the device being used?
Beyond administration in private practices and hospitals around the country, the University of Southern California, Emory University, Stanford University, Vanderbilt University, Medical College of Wisconsin, University of Arkansas, University of California San Diego, and Walter Reed Army Medical Center are presently using the device.

Can it be used in children?
Yes, the Dx–pH Probe can be used in children, even infants. Studies conducted by a pediatric pulmonologist in Ventura, CA have been performed in babies as young as three months.
Can the Dx–pH Measurement System be used in sleep labs concurrently with a sleep test?
The Restech "plug & play" Dx-Sleep Adapter™ accessory, released February 2006, allows sleep medicine professionals to track patients' airway pH events in real-time on their existing monitoring equipment. The Dx–System can be easily set up in a sleep clinic or physician's office. Since the device transfers data using wireless telemetry, there are no extra leads from the patient.

Can the Bravo™ be used concurrently with the Dx–pH Measurement System?
Yes, the Dx–pH Measurement System has a miniature 1.5mm Probe that is inserted trans-nasally, with a resting position posterior to the uvula. The Bravo system and Dx–System use different data transmission and recording devices, which can be used simultaneously. Presently, Dr. Tom DeMeester, Keck School of Medicine, USC (also head of Restech’s Scientific Advisory Board) is performing concurrent testing on patients using the Bravo and the Dx–pH Probe.

Why would I perform this test if I may have to perform a lower esophageal test as well?
The test is performed on patients whom you suspect have laryngopharyngeal reflux that is causing certain symptoms such as cough, throat clearing, hoarseness, etc. If the Dx–System test reveals episodes of lowered pH, the reflux can be treated in accordance to the symptoms. If a patient presenting the same symptoms reveals no change in pH, the reflux may not be causing the symptoms.

Can the probe be placed deeper in the airway, or in the esophagus?
Yes, the Dx–pH Probe can record liquid pH in the esophagus as well as aerosolized pH in the oropharynx. The placement of the Probe in the oropharynx, posterior to the uvula, seems to be the most comfortable location for the patient and the clinical results from this location accurately display supraesophageal pH levels attributable to gastric reflux events. Positioning the Probe in the lower pharyngeal area is possible, although not recommended because of possible patient discomfort.

How does the Dx–pH Probe stay in place?
After the probe is positioned, we recommend securing it using Tegaderm™ tape as close to the naris as possible. This will ensure that the probe does not slip out of the place. The catheter is constructed with a pliable plastic material that naturally wants to straighten out after curving through the nasal cavity. This helps keep the sensor pointing downward for optimum pH measurement.

Does the Dx—pH Measurement System™ measure aerosolized pH, liquid pH, or both?
The Dx–pH Probe was designed specifically for the purpose of measuring the pH of aerosolized reflux. It is extremely sensitive and can obtain readings from very little reflux action. The Dx–pH Probe does in fact work in a liquid environment, but because of its position above the upper esophageal sphincter (UES), its contact with refluxate is limited mainly to aerosol. This is because the UES acts as a final barrier to protect the delicate laryngeal tissue from acid exposure. Impedance technology has revealed that it is extremely rare to get a liquid event above the UES, and that nearly all events in this location are gaseous.