An acoustic neuroma is rare, noncancerous tumour arising from supporting cells that surround the vestibulocochlear nerve, usually within the internal auditory meatus (the canal in the skull through which the nerve passes from the inner ear to the brain).
Cause and incidence
Acoustic neuromas most commonly occur in people between the ages of 40 and 60 and are slightly more common in women than in men. Usually, the cause of an acoustic neuroma is unknown. However, tumours that affect the nerves on both sides of the head simultaneously may be part of a widespread neurofibromatosis (a disease characterized by changes in the nervous system, skin, and bones).
An acoustic neuroma can cause deafness, tinnitus (noises in the ear), loss of balance, and pain in the face and the affected ear. As the tumour enlarges, it may lead to additional complications, such as ataxia (loss of coordination) due to the compression of the brainstem and cerebellum.
Diagnosis and treatment
Diagnosis is made by hearing tests followed by X-rays or by CT scanning or MRI (techniques that produce cross-sectional or three-dimensional images of body structures). Surgery may be necessary to remove an acoustic neuroma, but treatment with radiotherapy to shrink it may also be effective.