Dual pH with Multichannel Intraluminal Impedance Testing in the Evaluation of Subjective Laryngopharyngeal Reflux Symptoms

Objectives. Minimal data exist to define the use of contemporary dual pH with multichannel intraluminal impedance (MII) probes integrating both pharyngeal acid and impedance sensors to evaluate laryngopharyngeal reflux (LPR) symptoms in a laryngology clinic population. This study was performed to review a series of patients tested with dual pH-MII for suspected LPR symptoms and to analyze pH-MII data findings for this patient cohort. Study Design. Case series with planned data collection. Setting. Tertiary laryngology clinic. Subjects and Methods. Patients with symptoms suggestive of possible LPR (dysphonia, chronic cough, globus sensation, subglottic stenosis,) were evaluated with a dual pH-MII system, as well as previously validated reflux finding score (RFS) and reflux symptom index (RSI) instruments. Results. A total of 109 patients were evaluated with dual pH-MII studies between 2010 and 2015, with 51 (47%) studies interpreted as positive'' for evidence of significant LPR, 43 (39%) as negative,'' and 15 (14%) as equivocal.'' Dual pH-MII data analysis showed that positive studies had an average of 2.84 pharyngeal acid exposures below pH 4 (vs 0.28 for negative) and 46 episodes of proximal reflux exposure (either acid or nonacid) by impedance detection (vs 30.6 for negative). RSI scores were significantly different between positive and negative studies, while RFS scores were not. Conclusions. Dual pH-MII analysis is a useful supplementary tool to provide objective evidence of pharyngeal reflux exposure in patients with suspected LPR. RSI scores appear to correlate with objective evidence of acid exposure in the pharynx, while RFS scores do not.