Bilateral hearing loss due to a meningioma located in the left posterior fossa: a case report.

We report the case of a 39-year-old woman with a left side meningioma, suffering from bilateral sensorineural hearing loss, who recovered audiometric hearing in both ears after surgery. A preoperative pure tone audiogram (PTA) revealed a bilateral sensorineural hearing loss. Several examinations for sensorineural hearing loss indicated cochlear and retrocochlear hearing loss in the left ear and cochlear hearing loss in the right ear. After the operation, bilateral hearing loss due to a left posterior fossa meningioma gradually improved. One year after surgery, with the exception of hearing at frequencies of 4 and 8 kHz in the left ear, the postoperative audiogram had improved to an almost normal level. We speculate that hearing loss in the left ear may have been induced by the indirect compression of the cochlear nerve caused by the tumor's edema, whereas that in the right ear may have resulted from changes in CSF pressure caused by the mass effects of the tumor.