In 1910 Verocay coined the term neurinoma in his description of a group of neurogenic tumors. Masson, in 1932, introduced the term schwannoma in an attempt to classify these tumors by their histologic appearance.
The acoustic neuroma is in fact neither acoustic nor a neuroma; it is a benign, slow-growing neoplasm that arises from the Schwann cells of the distal or neurilemmal portion of the eighth cranial nerve, most commonly from the superior vestibular division. These tumors appear to be encapsulated, however, this pseudo-encapsulation is caused by compression of the surrounding structures.
Acoustic neuromas or schwannomas, account for about 8% of all intracranial tumors, and for approximately 80% of all cerebellopontine angle tumors. Acoustic neuromas are usually unilateral, although they may develop bilaterally. They generally occur in the third to sixth decade of life and approximately 60% appear in women. These benign tumors are potentially life-threatening because of their close anatomical relationship to the cranial nerves and the brain stem. Patients with von Recklinghausen's disease (neurofibromatosis) have a higher probability of developing bilateral acoustic neuromas.