Acoustic neuroma

Synonyms

Vestibular schwannoma
Acoustic neurilemoma
Acoustic neurinoma
Cerebellopontine angle tumor
Neurinoma of the acoustic nerve
Acoustic tumor

Overview

Acoustic neuroma is an uncommon, noncancerous (benign) and usually slow-growing tumor that develops on the main nerve leading from your inner ear to your brain. Because branches of this nerve directly influence your balance and hearing, pressure from an acoustic neuroma can cause hearing loss, ringing in your ear and unsteadiness.

It is also known as vestibular schwannoma and it usually grows slowly or not at all. However, in a few cases, it may grow rapidly and become large enough to press against the brain and interfere with vital functions.

Symptoms

  • Gradual hearing loss
  • Ringing (tinnitus) in the affected ear
  • Loss of hearing in one ear
  • Symptoms of the tumor pressing on other nerve areas
  • Unsteadiness
  • Loss of balance
  • Dizziness (vertigo)
  • Facial numbness and
  • Weakness very rarely

Causes

The cause of acoustic neuromas — tumors on the main balance nerves leading from your inner ear to your brain (eighth cranial nerve) — appears to be a malfunctioning gene on chromosome 22. Normally, this gene produces a protein that helps control the growth of Schwann cells covering the nerves. What makes this gene malfunction isn't clear, and currently there are no known risk factors for getting an acoustic neuroma.

Scientists do know the faulty gene is inherited in neurofibromatosis type 2, a rare disorder that usually involves the growth of tumors on balance nerves on both sides of your head (bilateral vestibular schwannomas).

Diagnosis

Acoustic neuroma can be difficult to diagnose, because the symptoms are similar to those of middle ear problems. Ear exams, hearing tests, and scans can show if you have this disease.

Treatment

There are three treatment options available and which observation (if the tumor stays small), microsurgical removal (surgery) and radiation (radiosurgery or radiotherapy).

Resources

  • NIH