Analysis of pharyngeal swallowing in healthy subjects.

The Biomechanics of pharyngeal swallowing was investigated by videofluorography in 10 healthy subjects (9 men and 1 woman) during swallowing of 3 ml of fluid contrast medium and a small spoonful of jelly contrast medium. The items measured were the sequential movement of the hyoid bone: hyoid bone angle; epiglottis angle: antero-posterior diameters of the thyroid cartilage, larynx, hypopharynx, and pharyngoesophageal junction: and transport time of the swallowed bolus. It was concluded that the movement of the hyoid bone and thyroid cartilage and the angle of the epiglottis were important for evaluation of pharyngeal swallowing, and that the antero-posterior and vertical movement of the hyoid bone showed a significant relationship to transport time of the swallowed bolus as far as the esophagus, which was within 400 msec on average.