[Clinical value of multifrequential tympanometry].

Multi-frequency tympanometry brings into evidence, in the normal subject, three types of tympanogram of acoustic impedance. The frequency of the tone probe showing a W tympanogram seems to be the key element. This frequency is close to that of the resonance of the ear, which is altered in the case of pathology of the tympano-ossicular system and of increase in the pressure of the endolabyrinthine fluids. Multi-frequency tympanometry facilitates the differential diagnosis between ankylosis and a discontinuity of the ossicular chain. It also objectifies the variations in the pressure of the inner-ear fluids in Ménière's disease.