Esophageal swallowing phase assessed by audiosignal recording: relationship with manometry in gastroesophageal reflux disease patients

Abstract

The acoustic technique has been used for pharyngeal exploration but to date no such technique has been devised to assess esophageal motility. The aim of this study was to demonstrate that displacement through the esophagus can be quantified using this method in healthy subjects and in patients with gastroesophageal reflux. Concurrent manometric and acoustic recordings were also performed in the patients. Fifteen controls (38.5 +/- 13 years old) and 10 patients (34.9 +/- 6 years old) were included. All were recorded during wet and dry swallow sequences with microphones placed below the cricoid cartilage and on the xiphoid appendix. Standard manometry was performed for lower esophageal sphincter (LES) exploration. For the acoustic technique, the frequency of xiphoid signals (FX), esophageal transit time (ETT), duration of xiphoid sound (SD), and for the manometric study, the duration of LES relaxation (RD) were recorded and mean values were calculated (FXm), (ETTm), (SDm), (RDm). FXm for wet (94 vs 81.6%) and dry swallows (86 vs 66.6%) decreased in patients. ETTm was significantly higher (P < 0.01) for wet than for dry swallows (5.6 +/- 0.9 vs 5.2 +/- 1.2 sec) for controls but not for patients. ETTm was significantly higher for patients for wet (7.2 +/- 2.1 sec) and for dry swallows (6.5 +/- 2.3 sec) than for controls and SDm was lower. Xiphoid sound appeared in the second half of LES relaxation. Our noninvasive acoustic technique is simple and reproducible. It is well correlated with manometry, and it allows characterization of the displacement of the bolus through the esophagus and the LES. The technique could be used alone to determine appropriate pharmacological and surgical treatments for esophageal motility disorders.