Pharyngeal swallow adaptations to bolus volume measured with high‐resolution manometry

Abstract

Objective To determine the effect of bolus volume on pharyngeal swallowing using high resolution manometry (HRM). Study design Repeated measures with subjects serving as own controls. Methods Twelve subjects swallowed four bolus volumes in the neutral head position: saliva; 5 ml water; 10 ml water; and 20 ml water. Pressure measurements were taken along the length of the pharynx using a high resolution manometer, with emphasis placed on the velopharynx, tongue base, and upper esophageal sphincter (UES). Variables were analyzed across bolus volumes using three-way repeated measures analysis of co-variance (ANCOVA) investigating the effect of sex, bolus volume, and pharynx length. Pearson’s product moment tests were performed to evaluate how pharyngeal pressure and timing events changed across bolus volume. Results Velopharyngeal duration, maximum tongue base pressure, tongue base pressure rise rate, UES opening duration, and total swallow duration varied significantly across bolus volume. Sex did not have an effect, while pharynx length appeared to affect tongue base pressure duration. Maximum velopharyngeal pressure and minimum UES pressure had a direct relationship with bolus volume, while maximum tongue base pressure had an inverse relationship. Velopharyngeal pressure duration, UES opening duration, and total swallow duration increased as bolus volume increased. Conclusions Differences in pharyngeal pressures and timing of key pressure events were detected across varying bolus volumes. Knowing the relationships between bolus volume and pharyngeal pressure activity can be valuable when diagnosing and treating dysphagic patients. Level of evidence N/A.

The Effects of Bolus Volume and Texture on Pharyngeal Pressure Events Using High-resolution Manometry and Its Comparison with Videofluoroscopic Swallowing Study

“…15 However, in the present study, the duration of VP and the area integral of VP (not the maximal pressure) were significantly different (P < 0.05). In the previous study, the maximal pressure of VP did not correlate with the volume and the area integral was not evaluated as a variable.…”

“…In the previous study, the maximal pressure of VP did not correlate with the volume and the area integral was not evaluated as a variable. 15 Our result showed that the area integral of VP significantly correlated to the changes of volume. While maximal pressure can inform the important physiology of swallowing, it does not provide the complete aspect of the pharyngeal pressure generation.…”

“…Previous studies did not observe a change in TB pressure, 1,4 but a recent study using HRM showed that the TB pressure had an inverse relationship with bolus volume. 15 However, the correlation of the TB did not reach the significance level for maximal pressure (P = 0.199) and duration (P = 0.396), and only the ANCOVA analysis revealed significance. 15 Our results showed that all parameters of the TB were not significant, and follow up study is required.…”

“…13,14 Till now, few studies were performed to evaluate the effect of bolus volume and texture on the entire pharyngeal swallow with HRM. 15,16 HRM is capable of providing information on how the bolus volume and texture precisely affects swallowing physiology. If we employ new parameters based on anatomic structures that are important for the mechanisms of dysphagia, HRM could present more comprehensive and precise information for understanding dysphagia.…”

Effect of Bolus Volume and Viscosity on Pharyngeal Automated Impedance Manometry Variables Derived for Broad Dysphagia Patients

“…It is well understood that, during normal swallowing, mechanisms of bolus propulsion and clearance adjust in relation to volume and viscosity of the bolus to be swallowed (5,6). It is therefore reasonable to assume that bolus volume and consistency may influence pharyngeal AIM measurements.…”