[Progressive sensorineural hearing loss: neoplastic causes].

Acoustic neuromas represent about 90% of all space-occupying lesions of the cerebellopontine angle and account for approximately 6% of all intracranial tumors. Progressive unilateral sensorineural hearing loss is the most frequent initial symptom occurring in over 90% of patients. A sudden onset of hearing loss occurs in 5%, while 5% of cases present with normal hearing. The incidence of hearing loss does not seem to be related to tumor size. Accuracy of the tumor detection by gadolinium-enhanced magnetic resonance imaging has been reported as 99-100% even for intracanalicular tumors. The ABR false negative rate for intracanalicular tumors has been reported to be as high as 9-11%. Rare lesions of the cerebellopontine angle include: meningiomas, epidermoids, arachnoid cysts, trigeminal nerve neuromas, facial nerve neuromas, neurinomas of lower cranial nerves, glomus tumors and metastases. Therefore, a high suspicion index and awareness of symptoms and an adequate audiologic and neuroradiologic work-up are the clues to early diagnosis and appropriate surgical treatment.