Role of flexible laryngoscopy in evaluating aspiration

Flexible fiberoptic laryngoscopy is used to evaluate dysphagia, but its clinical utility has not been compared to that of the videofluorographic swallowing study (VFSS). This study correlates parameters of both procedures and identifies laryngoscopic predictors of aspiration in 105 patients. Presence of aspiration, pharyngeal residue, laryngeal sensation, vocal cord mobility, and glottic closure during flexible laryngoscopy (FL), and gag reflex were correlated with aspiration during the VFSS. An algorithm for laryngoscopically detecting aspiration was synthesized. Aspiration (p = .004) and pharyngeal residue (p < .00001) were highly correlated between the two studies. Aspiration during the VFSS was correlated with pharyngeal residue (p < .00001) and laryngeal sensation (p = .027) during FL, but not glottic closure (p = .169) nor vocal cord mobility (p = .056). Patients with a normal gag reflex and without aspiration or pharyngeal residue during FL had a 2.94% risk of aspiration during the VFSS. Flexible laryngoscopy can be used as a relatively safe, portable screening test for aspiration, but cannot always replace the VFSS to identify the presence or cause of aspiration.