Clinical Studies on Familial Deafness

A hundred and two patients in 59 families diagnosed as familial deafness at the Otolaryngological Department of the Hirosaki University Hospital during the past 6 years, were clinically observed. Forty-six casees were male and 56 female. In the majority of cases the onset of deafness startsed under 10 years old. Audiograms in most cases showed a descending type and bilateral audiograms were symmetrical in all except 3 cases. From the follow-up of hearing in 41 cases from 4 months to 6 years, it was suspected that the progression of hearing loss in many cases occurred gradually for a long period of time.