AURAL disease, particularly disease of the middle ear, is so prevalent that an intimate knowledge of the pathway of infection is necessary to the otologist.
The causes of otitis media, although numerous, may be summarized in the one phrase: "Obstructed and infected noses."1 As a general rule, contrary to the theory accepted by the laity, the tympanic membrane and the middle ear do not become infected through the external canal. In at least 95 per cent of cases infection spreads to the middle ear and the tympanic membrane by way of the eustachian tube. The importance of this tube is at once apparent, as it is the only portal of entry. Although its structure and relationship are clearly described in present day textbooks, one is apt to forget that little has been added to the knowledge of the eustachian tube during the past four hundred years. If any excuse is
TREMBLE GE. EUSTACHIAN TUBE. Arch Otolaryngol. 1947;46(2):211–220. doi:10.1001/archotol.1947.00690020220007