An acoustic neuroma is a tumor that grows on the nerve leading from the brainstem to the ear. This nerve plays a role in hearing and in maintaining your balance. An acoustic neuroma grows slowly. It is a benign tumor, which means it is not cancerous. However, this condition can still cause serious problems.

The Ear

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Causes

The exact cause of acoustic neuroma is unknown.

Risk Factors

Acoustic neuroma is most common between ages 30-60. Factors that may increase your chance of an acoustic neuroma include:

Symptoms

The first symptoms of an acoustic neuroma include:

  • Gradual hearing loss in one ear with near normal hearing in the other ear
  • Decrease in sound discrimination, especially when talking on the telephone
  • Ringing in the affected ear—tinnitus

As the neuroma gradually grows larger, symptoms may include:

  • Balance problems
  • Facial numbness and tingling
  • Weakness of the facial muscles on the side of the tumor

If headaches or mental confusion occurs, the tumor may be life threatening. Call your doctor right away.

Diagnosis

The doctor will ask about your symptoms and medical history. Your ears will be examined. Your doctor will also do tests of your nervous system.

Images may be taken of your head. This can be done with:

Tests may be done on your ears. These may include:

  • Audiogram
  • Auditory brainstem response test
  • Electronystagmography
Treatment

Treatment depends on your age, general health, the size and location of the tumor, and its rate of growth. Treatment may include:

Observation

If the tumor is very small, your doctor may just monitor its growth. About half will not grow any more. This is approach is common among people over age 70.

Microsurgical Removal

As the tumor grows and/or hearing becomes impaired, removal of the tumor may be necessary. The type of surgery depends on the size and location of the tumor. Complications of surgery may include permanent hearing loss and/or paralysis of facial muscles on the affected side.

Radiation Therapy

Radiation therapy is the use of radiation to kill cells and shrink tumors. Radiation is expected to prevent further growth of the tumor. Radiation may be used when tumors are small and surgery is not possible. This method may preserve hearing. It may be given over several treatments or as one large dose. You may be treated with a procedure called stereotactic radiosurgery. This surgery uses a focused beam of radiation to destroy the tumor tissue.

Prevention

There are no current guidelines for preventing acoustic neuroma because the cause is not usually known.