両側性聴神経腫よう症例の聴力低下の進行

Abstract

The diagnosis and treatment of patients with bilateral acoustic tumors are challenging problems for otologists because of possible bilateral hearing loss, facial palsy and poor prognosis. There has been no concensus about the appropriate type and time of treatment. In addition to surgical management, conservative treatment, such as chemotherapy and γ knife stereotaxic irradiation, has been advocated. For an assessment of the clinical effect of conservative treatment, a full knowledge of the natural history of bilateral acoustic tumors is essential. In this study, the hearing level deterioration is evaluated in 9 patients with bilateral acoustic tumors. The natural history of the clinical findings is described and the appropriate time for the initial treatment is suggested. Nine patients (18 tumors) aged 11 to 37 years were followed for 2 to 12 years. The hearing level was evaluated with pure tone average frequencies (250, 500, 1000, 2000, 4000 Hz). Although the development of hearing loss varied, deterioration of hearing was rapid in all patients. The rate of hearing level deterioration was correlated with age, but no significant correlation was noted between rate of hearing loss and age. Therefore, treatment should be initiated promptly in patients with bilateral acoustic tumors without considering the hearing level or age of the patient.