Cricopharyngeal Muscle Electromyography in Laryngopharyngeal Reflux

Abstract

The objective was to determine whether laryngopharyngeal reflux was associated with an electrophysiological abnormality of the main part of the upper esophageal sphincter, namely, the cricopharyngeal muscle, which could be related to laryngopharyngeal reflux symptoms. A prospective study of 20 patients with symptoms of laryngopharyngeal reflux. The diagnosis was based on clinical, laryngoscopic, and ambulatory 24-hour pH monitoring findings. Double-probe pH monitoring was performed with placement of the distal and proximal probes 5 cm above the proximal border of the lower esophageal sphincter and 15 cm proximal to the distal probe, in or just beneath the upper esophageal sphincter. Electromyographic recordings were obtained simultaneously on submental and cricopharyngeal muscles during water swallowing. The peak of the submental electromyographic amplitude and its duration was measured using bipolar surface electrodes placed under the chin. The electromyographic features of the cricopharyngeal muscle were investigated by means of concentric needle electrodes inserted percutaneously both in 20 normal subjects and in 20 patients with laryngopharyngeal reflux. All electrophysiological parameters were normal in all of the patients. The durations of foreburst revealed significant correlation with the number of reflux episodes and acid exposure time (P = .026 and P = .044, respectively). The duration of the foreburst correlating with acid exposure time and number of reflux episodes suggested that foreburst duration was extended because of the irritation caused by the acid reflux.