抄録
In 35 posterior fossa operations with intraoperative brain-stem auditory evoked potential (BAEP) monitoring, there were seven microvascular decompression (MVD) operations performed for five cases of hemifacial spasm and two of trigeminal neuralgia. Among these seven patients, three cases, two of hemifacial spasm and one of trigeminal neuralgia, showed postoperative hearing disturbance. In these cases, intraoperative BAEPs showed aggravations of all waveform components including wave I. Otoneurological examinations revealed the hearing disturbances were caused not only by retrocochlear lesions but also by cochlear lesions. These findings suggest that postoperative hearing disturbance after MVD surgery is deeply related to circulatory disturbance of the internal auditory artery.
