RESUMO
Through pure-tone audiometry, we studied the course of hearing recovery in 24 ears of 20 men (ages 18-48 years) who had acute acoustic sensorineural hearing loss (ASHL). All subjects were members of the Japanese Self-Defense Force. The hearing level in 5 ears returned to normal, the hearing level of 13 ears recovered but was not within the normal range, and the hearing level of 6 ears was unchanged. The time from noise exposure to presentation was longer in patients with unchanged hearing than in other patients. Recovery of hearing was poorest at 4,000 Hz, followed by 8,000 and 2,000 Hz. We concluded that hearing in patients with acute ASHL is likely to return to normal when the hearing level at 4,000 Hz recovers gradually; partial recovery of hearing is expected when the hearing level at 4,000 Hz reaches an early plateau.
Assuntos
Audiometria de Tons Puros , Dextranos/uso terapêutico , Armas de Fogo , Perda Auditiva Provocada por Ruído/tratamento farmacológico , Perda Auditiva Súbita/tratamento farmacológico , Militares , Doenças Profissionais/tratamento farmacológico , Prednisolona/uso terapêutico , Vitamina B 12/uso terapêutico , Adolescente , Adulto , Quimioterapia Combinada , Seguimentos , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/etiologia , Perda Auditiva Súbita/diagnóstico , Perda Auditiva Súbita/etiologia , Humanos , Japão , Masculino , Doenças Profissionais/diagnóstico , Doenças Profissionais/etiologiaRESUMO
Some hearing-impaired persons with hearing aids complain of listening difficulty under reverberation. No method, however, is currently available for hearing aid fitting that permits evaluation of hearing difficulty caused by reverberations. In this study, we produced speech materials with a reverberation time of 2.02 s that mimicked a reverberant environment (a classroom). Speech materials with reverberation times of 0 and 1.01 s were also made. Listening tests were performed with these materials in hearing-impaired subjects and normal-hearing subjects in a soundproof booth. Listening tests were also done in a classroom. Our results showed that speech material with a reverberation time of 2.02 s had a decreased listening-test score in hearing-impaired subjects with both monaural and binaural hearing aids. Similar results were obtained in a reverberant environment. Our findings suggest the validity of using speech materials with different reverberation times to predict the listening performance under reverberation of hearing-impaired persons with hearing aids.
