Laryngopharyngeal Sensory Deficits and Impaired Pharyngeal Motor Function Predict Aspiration in Patients Irradiated for Nasopharyngeal Carcinoma

Objectives/Hypothesis: To assess the contribution of laryngopharyngeal sensory deficits and impaired pharyngeal motor function to aspiration in patients irradiated for nasopharyngeal carcinoma. Study Design: A retrospective study at a tertiary referral university teaching hospital. Methods: One hundred consecutive patients who underwent radiotherapy for nasopharyngeal carcinoma referred to a dysphagia clinic underwent sensory testing of their laryngopharynx and endoscopic evaluation of their swallowing. The sensory threshold of the laryngopharynx was determined, the pharyngeal contraction assessed, and the status of the larynx and hypopharynx documented before and after swallowing. The presence of laryngeal penetration and aspiration was noted. Results: The average time from radiation therapy to assessment was 10.2 years, and the mean duration of swallowing symptoms was 27 months. Laryngopharyngeal sensation was deficient in 89% of patients and the pharyngeal contraction impaired in 93% patients. Laryngeal penetration and aspiration occurred in 87% and 74% of patients, respectively. Aspiration was associated with food residue in the pyriform fossae after swallowing (P < .001) and impaired pharyngeal contraction (P < .001), but not with laryngopharyngeal sensory deficiency. There was no association between a laryngopharyngeal sensory deficit and impaired pharyngeal contraction. Conclusions. Impaired pharyngeal contraction and food bolus clearance from the hypopharynx during swallowing are more important than laryngopharyngeal sensory deficiency in predicting aspiration in patients who underwent radiotherapy for nasopharyngeal carcinoma.