Experimental Study of the Pumping Function of the Eustachian Tube

Abstract

To determine the muscle responsible for the pumping function of the Eustachian tube and to examine the detailed processes of this function, we conducted (1) a measurement of tympanal pressure during swallowing and during selective stimulation of the tensor and the levator muscles, and (2) visual and radiographic observation of fluid in the tube; in cats, dogs and a monkey. the results were: (1) formation of negative pressure in the tube by contraction of the tensor muscle; and (2) displacement of the fluid from the tympanum to the pharynx through the tube by repeated contractions of the tensor. It was concluded that contractions and relaxations of the tensor muscle cause the pumping function of the tube, which expells any fluid from there into the pharynx.