[Normative Data of Pharyngeal and Upper Esophageal Sphincter High Resolution Manometry]

High resolution manometry (HRM) can provide information about the muscular contraction of the pharynx and the upper esophageal sphincter (UES) and represents an important tool in the diagnostics of dysphagia. To compare the results of swallowing studies interindividually and to identify pathological swallows, normative data are necessary. Normative data for the use of an HRM-probe with a large diameter has already been published. As previously has been shown these probes can influence the normal contraction of the pharynx and the UES. In this study comprehensive normal values are presented for small HRM-probes in diameter (2 mm), that only minimally affect pharyngeal and UES contractions.

29 healthy volunteers underwent pharyngeal and upper esophageal HRM. All subjects performed 10 water swallows of 2 ml in an upright position. Pressure and time dependent parameters of the velopharyngeal region, the tongue base and the UES have been evaluated. Mean and median values and different percentile ranges were calculated.

The normative values for the key parameters were (mean±SD): maximum velopharyngeal pressure 269.9±113.1 mmHg, maximum tongue base pressure 278±93.6 mmHg, maximum UES pressure 205.8±64.0 mmHg, UES resting pressure 42.5±18.7 mmHg and relaxation time of the UES 681.6±86.8 ms. Further parameters have been measured.

Time dependent values are comparable to those already published. Especially in the UES lower pressures can be measured when a small HRM-probe is used. The normative data established in this study might help to distinguish pathological from physiological swallows using HRM.