The Validity of the Pharyngeal Squeeze Maneuver

Abstract

Objective Pharyngeal strength is essential for safe bolus transit during deglutition. The pharyngeal squeeze maneuver (PSM) is a surrogate measure of pharyngeal strength determined on endoscopic swallow evaluation (FEES). Although several investigations have utilized the PSM, the validity of this diagnostic assessment has never been tested. The purpose of this investigation was to evaluate the clinical validity of the PSM. Methods Simultaneous FEES and fluoroscopic swallow evaluations were prospectively performed on 30 consecutive patients being evaluated for dysphagia. The PSM was assessed on all patients and compared to a validated measure of pharyngeal strength on fluoroscopy, the pharyngeal constriction ratio (PCR). As pharyngeal strength diminishes, the PCR increases. The PCR in patients with an intact PSM was compared to the PCR in persons with an absent PSM, with the independent samples t-test and confirmed with the non-parametric Mann-Whitney test. Results 29 simultaneous FEES-fluoroscpic swallow studies were performed. 75% (22/29) had an intact PSM and 25% (7/9) had an absent PSM. The mean PRC for the group with an intact PSM was 0.06 (± 0.08), compared to a mean PCR of 0.31 (± 0.20) for individuals with an absent PSM. The PCR was significantly higher, indicating a weaker pharynx, in persons with an absent PSM (p < 0.001). Conclusions Pharyngeal strength, as assessed with the PCR, is significantly weaker in persons with an absent PSM. These data suggest that the PSM is a valid surrogate measure of pharyngeal motor integrity.