Tympanometry and acoustic impedance.

In recordings of the acoustic impedance of the middle ear (tympanometry) the change in air pressure in the ear canal will mostly influence the capacitive component of the acoustic impedance. By choosing a probe tone frequency close to the resonance frequency of the middle ear, characteristic tympanometric patterns can be demonstrated in certain middle ear lesions. The shapes of the curves are discussed in relation to the behaviour of the different components of the middle ear impedance.