Abstract
Configuration analyses of epipharyngeal aperture, laryngeal vestibular area, intercuneiform cartilage width, posterior and anterior pharyngeal prominence and lateral pharyngeal constriction, were statistically undertaken during swallowing utilizing a fine caliber fiberoptic. A fiberscope is inserted and fixed in the epipharynx through the nostril to obtain a clear precise view of the larynx and hypopharynx like a bird's-eye view. The following findings were clarified. Constrictive forces due to the aryepiglottic folds precede the epiglottis narrowing before its tilting toward the laryngeal aperture. Posterior muscle forces mainly resulting from the superior pharyngeal constrictor muscle are stronger than the anterior muscle forces lekely to be due to the tensor veli palatine muscle at the epipharyngeal level during swallowing. Cuneiform movements and narrowness of the laryngeal vestibule demonstrated that glottic closure precedes tilting of the epiglottis.
