Acoustic Neuromas are tumors of the Schwann cell sheath of Vestibular or Cochlear Nerve. It is intracranial and extra axial. Acoustic Neuromas consists of about 80% of tumors found in Cerebellopontine angle and they occupy significant amount of space in cerebellopontine angle once they grow up. The remaining tumors are meningiomas, lipomas or metastatic lesion.
Tumor - acoustic
Cerebellopontine angle tumor
The incidence of Acoustic Neuroma is on the increase and is around 0.7 to 1 in 100000 persons. The incidence has increased with the newer methods now at hand of diagnosis like CT scan and MRI. Also it is seen that many Acoustic Neuromas never become apparent clinically and are only identified in autopsy.