Acoustic immittance testing of the Eustachian tube.

The pathophysiological relationship of Eustachian tube dysfunction to middle ear effusion is widely accepted. Several techniques have been developed for utilizing the clinical measurements of acoustic immittance to assess the ventilatory status of the Eustachian tube. This article describes the array of procedures currently in use as well as a selection of procedures being developed for clinical assessment of the Eustachian tube. Most studies in this area have concentrated on measurements of normal function. Clinicians and researchers are encouraged to increase the application of these techniques in order to broaden the data base that is currently available concerning normal and pathological function.