What is acoustic neuroma?

Acoustic neuroma is a rare noncancer tumor. It grows slowly from an overproduction of Schwann cells and is also called a vestibular schwannoma. The tumor then presses on the hearing and balance nerves in the inner ear. Schwann cells normally wrap around and support nerve fibers. A large tumor can press on the facial nerve, which controls facial muscles and sensation. Or it can press on brain structures.

There are 2 types of acoustic neuromas:

• Unilateral acoustic neuromas. This type affects only one ear. It's the most common type of acoustic neuroma. This tumor may develop at any age. It most often happens between ages 30 and 60. Acoustic neuroma may be the result of nerve damage caused by environmental factors. The only certain environmental risk factor is past radiation to the head. It's unclear if prolonged exposure to loud noises is a cause of acoustic neuromas.

• Bilateral acoustic neuromas.  This type affects both ears and is inherited. It's caused by a genetic problem called neurofibromatosis-2 (NF2).

What causes acoustic neuroma?

Acoustic neuroma can be caused by:

• Neck or head radiation. This can lead to acoustic neuroma many years later.

• Neurofibromatosis type 2 (NF2). People with this disease are at higher risk. NF2 can run in families.

What are the symptoms of acoustic neuroma?

These are the most common symptoms of acoustic neuroma:

• Hearing loss on one side, can’t hear high-frequency sounds

• Feeling of fullness in the ear

• A ringing in the ear (tinnitus), on the side of the tumor

• Dizziness

• Balance problems or unsteadiness

• Facial numbness and tingling with possible paralysis of a facial nerve (this is rare)

• Headaches, a clumsy walk, and mental confusion

The symptoms of acoustic neuroma may look like other conditions or health problems. Always talk with your healthcare provider for a diagnosis.

How is acoustic neuroma diagnosed?

Acoustic neuromas look like other middle and inner ear problems. They may be hard to diagnose. An ear exam and a hearing test are often done first. A CT scan and MRI can help to find and measure the tumor.

How is acoustic neuroma treated?

Treatment will depend on your symptoms, age, and general health. It will also depend on how severe the condition is.

Treatment may include watching and waiting, surgery, or radiation. Surgery for larger tumors can damage hearing, balance, and facial nerves. Another treatment choice is radiosurgery, often called the gamma knife. This uses focused radiation to reduce the size or blunt the growth of the tumor.

What are possible complications of acoustic neuroma?

If the tumor gets big enough, it can press against the brain stem. This can affect neurological function or even become life-threatening.

Key points about acoustic neuroma

• Acoustic neuroma is a noncancer tumor. It affects hearing and balance when the tumor presses on the nerves in the inner ear.

• It's a rare tumor that affects middle-aged people.

• It can be caused by radiation exposure to the head and neck. Some types are inherited.

• It's diagnosed using hearing tests and imaging tests.

• Treatment can include watching and waiting, surgery, or radiation.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.

• Before your visit, write down questions you want answered.

• Bring someone with you to help you ask questions and remember what your provider tells you.

• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.

• Ask if your condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if you do not take the medicine or have the test or procedure.

• If you have a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your provider if you have questions.