Elevation of the larynx on normal and abnormal cineradiogram.

The relationship between bolus volume (2.5, 5, 10 and 20 ml) and larynx elevation during swallowing was assessed in 10 non-dysphagic and 10 dysphagic individuals without pharyngeal dysfunction. Laryngeal elevation in different types of pharyngeal dysfunction was assessed in 60 non-dysphagic and 75 dysphagic patients. All subjects were examined with liquid barium and cineradiography at 50 frames/s. The laryngeal elevation was measured at the moment when the bolus reached the level of the valleculae and at maximum elevation. Elevation of the larynx, both the initial and maximal, was not influenced by sex, age or presence of dysphagia. Elevation of the larynx at the moment when the bolus reached the valleculae, when expressed in per cent of maximum elevation, was lower with 10 and 20 ml bolus volumes compared with 2.5 ml bolus volume (p < 0.05) in the 10 dysphagic individuals. Pharyngeal dysfunction was associated with significantly lower initial elevation of the larynx, at the moment when the bolus reached the level of the valleculae, although the maximal laryngeal elevation was normal. Initial elevation was 30% lower (p = 0.03) in patients with aspiration of bolus material into the trachea, 22% lower (p = 0.007) in those with defective closure of the laryngeal vestibule without aspiration and 16% lower (p = 0.06) in those with incoordination of the cricopharyngeal muscle compared with patients without dysfunction.