Abstract
Histological evidence of otosclerosis was found in the 7 temporal bones of 6 persons out of a total of 440 ears removed from 223 Japanese. The frequency of the histological otosclerosis was 1.59%. The area anterior to the oval window was involved in 4 ears. The area anterior internal auditory canal was involved in 1 ear. The multiple areas (semicircular canals and cochlear wall) were involved in 2 ears. Most ears had inactive foci and had no stapes fixation. We thought that the reason why the incidence of otosclerosis among Japanese was low was not only the low frequency but also the low activity of the otosclerosis foci.
