Cineradiography of the pharyngeal stage of deglutition in 150 individuals without dysphagia.

With the aid of cineradiography the pharyngeal stage of deglutition was examined at a speed of 50 and 100 frames per second among 150 individuals without dysphagia. In 124 (83%) the act of swallowing had a symmetrical and synchronous pattern. Different types of aberrations from this pattern were registered in 26 individuals (17%). In seven individuals the epiglottis did not tilt down properly but remained in a transverse position during deglutition. In eight individuals, contrast medium passed into the laryngeal vestibule. Seven individuals had a dysfunction of the cricopharyngeal muscle which did not relax properly. One individual had a web in the upper oesophagus. In all but two individuals the aberrations were isolated and not concomitant with other abnormalities of the act of swallowing.