Relationship between fluoroscopic and manometric measures of pharyngeal constriction: The pharyngeal constriction ratio

Objectives: The gold standard objective measure of pharyngeal strength is pharyngeal manometry. We have developed an objective fluoroscopic measure of pharyngeal strength, the pharyngeal constriction ratio (PCR). A high PCR indicates poor pharyngeal constriction. The objective of the current study was to evaluate the correlation between the PCR and peak pressures on pharyngeal manometry. Methods: The charts of 20 consecutive individuals who underwent a dynamic fluoroscopic swallow evaluation and pharyngeal manometry at the Center for Voice and Swallowing of the University of California, Davis, were retrospectively reviewed. Information regarding patient demographics, diagnoses, PCR, and manometric pharyngeal peak pressures was abstracted. The correlation between the PCR and pharyngeal pressure was determined with the Pearson correlation coefficient. Results: The mean (+/- SD) age of the cohort was 63 +/- 11 years. Fourteen of the 20 patients (70%) were male. The most common diagnoses were reflux (7 of 20) and cerebrovascular accident (4 of 20). The mean PCR was 0.26 +/- 0.31. The mean pharyngeal pressure was 83 +/- 43 mm Hg. The correlation between the PCR and pharyngeal pressure was -0.70 (p < .01). Conclusions: There was a high inverse correlation between the PCR and the peak pharyngeal pressure on manometry (-0.70). The PCR appears to be a valid objective surrogate measure of pharyngeal strength.