Differential diagnostic value of tympanometry in adhesive processes and otosclerosis

280 tympanograms were recorded in sound-conductive hearing loss to assess their value in the differential diagnosis of otosclerosis and adhesive process. A normal tympanogram can be recorded in otosclerosis, In 48% of adhesive processes a more or less normal impedance pattern can be demonstrated. Therefore, in evaluating tympanograms in adhesive processes, one must take into consideration the microscopic picture of the eardrum and its mobility.