Acoustic impedance of pathological ears.

Abstract

The report reviews the clinical usefulness of acoustic impedance measurements at the eardrum as well as the currently used instrumentation and methods. The conclusion is reached that both absolute and relative impedance measurements can be made with the acoustic bridge as well as with appropriate probetube techniques. The absolute measurements are the most generally applicable since they do not depend on the neural portions of the auditory system. A number of cases where impedance measurements were found to be of particular value are described. The acoustic symptomatology of the most frequent pathologies is summarized in a table. (Modified author abstract)