[Anatomy of the eustachian tube].

The auditory tube is part of a complex anatomical functional system, which even today is not completely explained. It plays a crucial role in the understanding of the pathogenesis of chronic middle ear infections and possible therapeutic interventions--particularly in infants. This paper summarizes the current knowledge of eustachian tube gross anatomy and histology, its peritubular structures and its topographic relationship to the internal carotid artery in adults. Anatomical aspects specific to infancy are related to their possible influence on tube function.