Mechanisms of the Gas Exchange in the Normal Human Middle Ear

Abstract

The spontaneous rate of the middle ear ventilation through the Eustachian tube in the aural flow direction was determined on 3 normal subjects for some hour by a pressure-flow technique. This rate of ventilation was considered to reflect the normal rate of gas volume absorption from the middle ear space to the blood. Assuming that the rate of ventilation determined is valid for 24 hours, the daily ventilation through the Eustachian tube into the middle ear for obtaining normal ear pressure conditions only reaches 1—2 ml. Finally two accessory mechanisms are discussed which may facilitate the ventilation of the middle ear.