1967 Volume 10 Issue 4 Pages 326-334
We observed clinically on 274 cases who visited the Hearing and Speech Clinic for children in Tokyo University Hospital from July 1965 to June 1966.
The following results were obtained.
1) Of 274 cases 156 cases were male and 118 cases were female. Sixty-two per cent of them were under three years of age.
2) The grade of hearing impairments was measured by conditioning orientation reflex, play audiometry, E. E. G. audiometry, and standard audiomotry. Percentage of the slight hearing loss cases (hearing loss of 20 to 40dB) was 22%, that of the medium hearing loss cases (hearing loss of 40 to 70dB) was 39% and that of the severe hearing loss cases (hearing loss of 70dB over) was 25%.
Our deaf children of 28per cent had mental retardation. These children with double handicaps (hearing impairment and mental retardation) should be paid attention to at their diagnosis and treatment.
3) Speech development of children with hearing disorders was delayed one or two years of age if not educated, as compared with that of normal children. Particularrly, its delay of the severly impaired deaf children was great.
4) Analysing the causes of impaired hearing of 274 cases, hereditary predispositions, convulsion, disturbances of pregnancy, brain damage on delivery and premature were significant factors.