What is acoustic neuroma? Acoustic neuroma (also called vestibular schwannoma) is a tumor in the tissue that surrounds the nerve that connects the inner ear to the brain. It is usually a benign tumor but it can eventually lead to hearing loss because the tumor presses against the nearby auditory nerve. This nerve, which is also known as the eighth cranial or vestibulocochlear nerve, transmits information about sound and balance to the brain. Acoustic neuroma is a relatively rare condition, affecting two persons out of 100,000, and typically occurs in people between the ages of 30 and 60.(Source: ANAUSA). Acoustic neuroma is caused by a defect that results in the irregular growth of Schwann cells, which are a type of supporting cell in the nervous system. In some people, acoustic neuromas may be caused by a genetic predisposition. In others, the cause is not known. If your tumor is very small and does not cause symptoms, your doctor may choose to watch and wait, that is, to monitor the tumor carefully to ensure that it does not grow. Radiation and surgery are other treatment options. Treatment is necessary if there is a possibility that the tumor may grow and press against your brainstem, which could cause serious complications. Although acoustic neuroma is benign and grows slowly, it can produce disturbing symptoms. Seek immediate medical care (call 911) if you, or someone you are with, have any serious symptoms, including hearing loss in one or both ears, dizziness, loss of muscle coordination, or numbness on both sides of the face.