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Updated: Jul 9, 2026

Coordinate Mapping of Hyolaryngeal Mechanics in Swallowing
Published on: May 6, 2014
Can a fluoroscopic estimation of pharyngeal constriction predict aspiration?
Helena Yip1, Rebecca Leonard, Peter C Belafsky
1Center for Voice and Swallowing, Department of Otolaryngology-Head and Neck Surgery, University of California at Davis, 2521 Stockton Boulevard, Sacramento, CA 95817, USA.
Background:
The pharyngeal constriction ratio (PCR) is a ratio of pharyngeal area measured in lateral fluoroscopic view at the point of maximum pharyngeal constriction during the swallow to the pharyngeal area measured with the bolus held in the oral cavity. We hypothesize that the PCR may represent a surrogate measure of pharyngeal strength.
Objective:
To investigate the relationship between the PCR and aspiration.
Study Design And Setting:
Data from a computerized clinical database of individuals undergoing a videofluoroscopic swallow evaluation at a tertiary academic swallowing center was acquired.
Results:
Two hundred sixty videofluoroscopic studies were abstracted. The mean PCR was 0.32 (+/- 0.02) for individuals who aspirated and 0.20 (+/- 0.02) for individuals who did not (P < 0.001). In a multiple logistic regression analysis, the PCR was significantly associated with the prevalence of aspiration (P < 0.01). Individuals with a PCR greater than 0.25 were 3 times more likely to aspirate (95% CI = 1.7, 5.1).
Conclusions:
The pharyngeal constriction ratio is associated with the presence of aspiration on fluoroscopy. Before the PCR can be used as a surrogate measure of pharyngeal constriction, correlation with pharyngeal manometry will be necessary.
Significance:
The pharyngeal constriction ratio is associated with the presence of aspiration on fluoroscopy.
Ebm Rating:
B-3b.
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