Normative Reference Values for Pharyngeal Volume and Residue During Swallowing in Healthy Adults: Analysis Using...

Area of Science:

• Swallowing physiology
• Quantitative imaging analysis
• Biomechanical engineering

Background:

• Pharyngeal swallowing is crucial for nutrient intake and airway protection.
• Quantitative assessment of pharyngeal function is essential for diagnosing dysphagia.
• Existing reference values for pharyngeal swallowing parameters are limited.

Purpose of the Study:

• To establish normative reference values for pharyngeal volume and residue during swallowing in healthy adults.
• To investigate the influence of age, sex, height, and bolus properties on pharyngeal swallowing measurements.
• To provide a basis for comparing individuals with and without pharyngeal impairments.

Main Methods:

• Retrospective analysis of 288 swallows from 135 healthy Japanese adults using Swallowing CT.
• Quantitative measurements of pharyngeal cavity volume at bolus hold (PVHOLD), maximum pharyngeal constriction (PVMAX), pharyngeal volume constriction ratio (PVCR), and post-swallow residue.
• Semi-automated software used for dynamic 3D-CT image analysis.

Main Results:

• Established normative values (median [97.5th percentile]) for PVHOLD (20.9 cm³ [38.6 cm³]), PVMAX (0.3 cm³ [2.1 cm³]), PVCR (98.8% [89.1%]), and residue (0 cm³ [0.4 cm³]).
• Males exhibited larger pharyngeal volumes than females.
• PVHOLD increased with height and age; PVMAX and PVCR increased with larger and thicker boluses.
• Pharyngeal residue was associated with increasing bolus volume, age, and thicker bolus consistency.

Conclusions:

• Normative reference values for pharyngeal swallowing volumes and residue were established using Swallowing CT.
• Demographic factors and bolus properties significantly influence pharyngeal swallowing dynamics.
• These findings provide a quantitative foundation for clinical assessment and diagnosis of pharyngeal swallowing disorders.