[Impedance measurements and otosclerosis (author's transl)].

Impedance measurements (model Madsen ZO 72) were performed on 158 patients with otosclerosis and compared with the operative findings. It was found that otosclerosis shows in 95% of the cases a symmetrical tympanogram, type A. Its amplitude does not differ from the standard values: that means that otosclerosis does not correlate with a flattened amplitude of the tympanogram. In addition there is no correlation between the intraoperative finding and the ampitude. The stapedius reflex could not be elicitated by acoustic stimuli.