To determine the morphological development of the human larynx during the embryonic period, serial sections of 20 embryos have been examined.
By 4 weeks of fertilizion age, the median pharyngeal groove, the laryngotracheal sulcus and the tracheoesophageal septum were formed. At the 5th week. The hypopharyngeal eminence, the laryngotracheal conduit, the laryngeal inlet and the arytenoid
swellings were observed. In the 6th week, the larynx was recognized as a T-shape and the hyoid eminence was observed. In the 7th week, the epiglottis, thyriod and cricoid condensations, hypoglossal nerve, superior and inferior laryngeal nerves
were
appeared. The vestibulotracheal canal was formed. In the 8th week, the laryngotracheal canal was obliterated and the laryngeal ventricle was observed beneath the vestibulotracheal canal. The communication between the vestibulotracheal canal and
the
laryngotracheal canal was not occurred at the end of the embryonic period. (Korean J Otolaryngol 38:4, 1995)
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