Transient and Quasi-Static Tympanometry

Abstract

The magnitude and the sign of the rate of pressure change, used to record tympanograms, have a pronounced effect on the aspect of these curves. For diagnostic purposes, abnormal tympanograms are often more evident at high rates (30 mm H2O/sec). Stable results for the value of the acoustic impedance are only obtained when the maxima of the curves are recorded at extreme low rates of pressure change (1 mm H2O/sec). These values (at least for normal ears with a cavity pressure near atmospheric pressure) must be in better agreement with static values obtained with a Zwislocki acoustic bridge.