Detection and Patterns of Pharyngeal Reflux Events With Two Ambulatory Pharyngeal Impedance-pH Monitoring Systems: A Comparative Study.

Objective: To investigate the detection and patterns of pharyngeal reflux events in laryngopharyngeal reflux disease (LPRD) patients according to the type of ambulatory hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH) system used and assessed whether potential HEMII-pH differences impact the pretreatment to post treatment findings.

Methods: Patients with laryngopharyngeal symptoms and findings and an objective LPRD diagnosis were prospectively recruited from the European Reflux Clinic from January 2017 to December 2024. The objective diagnosis was supported by two different HEMII-pH systems (Medtronic and Sandhill). The profiles of LPRD on the objective testing devices (acid, weakly acid, and alkaline LPRD) of patients from the same clinic were prospectively compared. Reflux symptom scores (RSS) and reflux sign assessment (RSA) were used to document prepersonalized to postpersonalized treatment symptoms and findings. A study of the correlation between HEMII-pH features, symptoms, and signs was conducted.

Results: The study included gender- and age-matched 101 patients with a Sandhill HEMII-pH and 102 patients with a Medtronic HEMII-pH. Both systems detected distal esophageal reflux events similarly, but Medtronic detected significantly more pharyngeal reflux events. The Sandhill group showed higher proportions of acid and weakly acid LPRD, while Medtronic patients predominantly had alkaline reflux. Patients of both groups demonstrated significant RSS reduction after treatment (P = 0.001), with a trend toward higher response rates in the Sandhill group (P = 0.067). Symptom scores were better correlated to the Sandhill pharyngeal reflux event features than the Medtronic one.

Conclusion: The patterns of LPRD can substantially vary according to the type and catheter configuration of ambulatory HEMII-pH systems used. The differences between HEMII-pH devices support the need for revising consensus statements defining the thresholds of pharyngeal reflux events for confirming the LPRD diagnosis.