A Novel Quantitative Measure of Pharyngeal Shortening

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 Evidence3 Laryngoscope, 2023