[The analysis of abnormal auditory brainstem responses].

The abnormal auditory brainstem responses (ABR) of 56 cases who had different retrocochlear disorders were analysed. These disease included acoustic neuroma, glioma, cholesteatoma, astrocytoma, meningoma in cerebellopontile angle (CPA), chromaffin tumor of jugular foramen, intracranial metastatic tumor, demyelinating disease, multiple cranial nerve paralysis, hepatolenticular degeneration, other CPA tumors, expansion or stenosis of internal auditory meatus (IAM), and so on. The ABR features were varied in these diseases, even in same disease. In general, the wave latencies and interwave periods prolonged in the disorders which occupied place in CPA, the differentiation of wave was not clear and/or the wave was not well repeated in the disorders which spreaded all over the brain. The cause of abnormal ABRin which CT and/or MRI were normal was also analysed. The ABR detection is a sensitive indication in retrocochlear lesions.