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Updated: Jul 12, 2025

Coordinate Mapping of Hyolaryngeal Mechanics in Swallowing
Published on: May 6, 2014
A Novel Quantitative Measure of Pharyngeal Shortening
Rebecca Leonard1, Anna Miles2, Lise Bakker2
1Department of Otolaryngology, University California, Davis, Davis, California, USA.
Background:
Little is known about pharyngeal shortening (PShort) during swallowing. This observational study measured PShort during swallowing in healthy adults and compared it to patients with swallowing impairments of different aetiologies.
Methods:
275 healthy volunteers (19-99 years) and 75 dysphagic patients (25 with head and neck cancer, 25 with Parkinson's, 25 with stroke) underwent videofluoroscopy. A novel quantitative measure of PShort for 1, 3, and 20 mL thin liquid barium and 3 mL paste boli was determined and compared across age, sex, bolus type and patient cohort.
Results:
PShort ranged from 1.05 to 4.41 cm across bolus types with larger displacements for 20 mL (M: 2.52 cm) and paste (M: 2.43 cm) compared with 1 mL (M: 2.36 cm) and 3 mL (M: 2.41 cm). PShort correlated with sex, height, and cohort but not age. Inter-rater reliability for three raters was substantial (intraclass correlation >0.80).
Conclusions:
This novel fluoroscopic measure of PShort is reliable and demonstrates quantitative changes in vertical pharyngeal displacement in healthy and swallow-impaired adults related to sex, size, and bolus type.
Level Of Evidence:
3 Laryngoscope, 134:2121-2126, 2024.

