Measurement of eustachian tube function using sonotubometry.

Sound transport through the Eustachian tube in normal ears has been recorded using sonotubometry (Virtanen, 1978). It was found that only 66% of the ears had sound transport through the tube when swallowing. Despite the fact that all ears had adequate aeration of the middle ear at the time of testing, 34% of the ears had no sound passage when swallowing. The explanation for this phenomenon is discussed. Also, it is concluded that this test may reflect Eustachian tube patency during swallowing--and not tubal function.