This growth is a benign tumor that forms on the vestibulocochlear nerve. This nerve leads from the inner ear to the brain. Acoustic neuromas usually grow slowly and do not spread. However, they can eventually grow so large that they press against surrounding structures, including the brain and other nerves.
An acoustic neuroma results from an abnormal growth of Schwann cells. These specialized cells encase the fibers of the vestibulocochlear nerve. Abnormal growth of these cells has been linked to a genetic malfunction.
Acoustic neuromas generally develop in people between the ages of 30 and 50. Symptoms may include a ringing sound in the ear (called tinnitus), facial weakness, difficulty swallowing and dizziness. In most cases, an acoustic neuroma forms on only one side of the head. When neuromas occur on both sides of the head, they are generally associated with a rare disorder called neurofibromatosis 2.
Treatment options depend on the patient and on the characteristics of the tumor. If a neuroma isn’t causing problems, and if it is not growing rapidly, a physician may recommend monitoring without treatment. If treatment becomes necessary, options may include surgery and radiation therapy.