[Impedance measurement for the diagnosis of middle ear effusions (author's transl)].

Impedance measurement is especially important for the diagnosis of middle ear effusions with pre-school-children. Instead of simply classifying into different tympanogram types, a descriptive analysis of each parameter is preferable. The presence of the stapedius reflex, middle ear pressure, form of peak, compliance and gradient of the tympanogram are discussed separately as to their sensitivity and specificity regarding diagnosis of effusion. The diagnostic certainty of the tympanogram is thereby considerably increased.