Automatic audiometry in stapes motility evaluation.

An automatic Grason-Stadler-Békésy 1701 audiometer with continuous frequency progression (1 octave/min) and increase (or attenuation)of intensity of 2.5 dB/sec, has been employed to perfect an investigation technique for obtaining, by the mean difference in dB between absolute bone conduction (ABC) and relative bone conduction(RBC), a quantity evaluation of stapes motility and monitor alterations brought on by various disease processes. A preliminary study performed on subjects with normal hearing was used to establish the influence of age on motility. It was thus possible to establish an index (stapes motility index, SMI) to represent the degree of normal stapes motility as a function of the subject's age and thus, through variations in this index, identify alterations to the motility of the tympano-ossicular system caused by ongoing disease processes and by surgery.