The early symptoms of an acoustic neuroma are often subtle. Many people attribute the symptoms to normal changes of aging, so it may be a while before the condition is diagnosed.
The first symptom is usually a gradual loss of hearing in one ear, often accompanied by ringing in the ear (tinnitus) or a feeling of fullness in the ear. Less commonly, acoustic neuromas may cause sudden hearing loss.
- Problems with balance
- Vertigo (feeling like the world is spinning)
- Facial numbness and tingling, which may be constant or come and go
- Facia weakness
- Taste changes
- Difficulty swallowing and hoarseness
- Clumsiness or unsteadiness
The exact cause of an acoustic neuroma is unknown. Most cases seem to arise for no apparent reason (spontaneously). No specific risk factors for the development of these tumors have been identified.
A variety of potential risk factors for acoustic neuroma have been studied including prior exposure to radiation to the head and neck area (as is done to treat certain cancers) or prolonged or sustained exposure to loud noises (as in an occupational setting). Acoustic neuromas occur as part of a rare disorder known as neurofibromatosis type II. T
An acoustic neuroma arises from a type of cell known as the Schwann cell. These cells form an insulating layer over all nerves of the peripheral nervous system (i.e., nerves outside of the central nervous system) including the eighth cranial nerve. The eighth cranial nerve is separated into two branches the cochlear branch, which transmits sound to the brain and the vestibular branch, which transmits balance information to the brain.
More about Treatment
An acoustic neuroma is a noncancerous growth that develops on the eighth cranial nerve. Also known as the vestibulocochlear nerve, it connects the inner ear with the brain and has two different parts. One part is involved in transmitting sound; the other helps send balance information from the inner ear to the brain.
Acoustic neuromas -- sometimes called vestibular schwannomas or neurilemmoma -- usually grow slowly over a period of years. Although they do not actually invade the brain, they can push on it as they grow. Larger tumors can press on nearby cranial nerves that control the muscles of facial expression and sensation. If tumors become large enough to press on the brain stem or cerebellum, they can be deadly.
There are three main courses of treatment for acoustic neuroma:
- Observation is also called watchful waiting. Because acoustic neuromas are not cancerous and grow slowly, immediate treatment may not be necessary. Often doctors monitor the tumor with periodic MRI scans and will suggest other treatment if the tumor grows a lot or causes serious symptoms.
- Surgery for acoustic neuromas may involve removing all or part of the tumor.
- Radiation therapy is recommended in some cases for acoustic neuromas. State-of-the-art delivery techniques make it possible to send high doses of radiation to the tumor while limiting expose and damage to surrounding tissue.