Gamma Knife treatment for acoustic neuroma
What to know about acoustic neuroma and Gamma Knife treatment
- An acoustic neuroma is a rare, non-cancerous tumor in the skull that affects the inner ear. As the tumor grows, it can press against nerves and cause hearing loss and balance problems. Acoustic neuromas usually grow slowly.
- Treatment for acoustic neuroma will vary depending on the size of the tumor and the age of the patient. Treatment options range from observation (watching and waiting), to removal surgically, to stopping tumor growth using Gamma Knife stereotactic radiosurgery.
- Gamma Knife is ‘brain surgery without the surgery part.’ Gamma Knife focuses multiple beams of radiation to intersect at a single target—the tumor—to effectively stop tumor growth without harming surrounding tissue.
- Gamma Knife is an excellent treatment option for people whose advanced age or other medical conditions do not make them good surgical candidates.
- Treatment for acoustic neuroma, whether surgery or radiation, can preserve hearing, but it cannot restore hearing that has been lost.
What is an acoustic neuroma?
An acoustic neuroma (also known as a vestibular schwannoma) is a non-cancerous tumor that develops from the balance and hearing nerves that supply the inner ear. As the tumor grows, it presses against the hearing and balance nerves. Acoustic neuromas generally affect only one ear. Bilateral acoustic neuromas (in both ears) can occur in neurofibromatosis type II, a hereditary disorder, and account for approximately five percent of cases. Acoustic neuromas make up about eight percent of all tumors found inside the skull. Each year, about one in every 100,000 people develops an acoustic neuroma.
Symptoms of acoustic neuroma
Signs and symptoms of acoustic neuroma come on slowly, because the tumor itself is usually slow-growing. People generally first notice symptoms between the ages of 30 and 60. Symptoms of acoustic neuroma may include:
- Hearing loss
- Tinnitus (ringing in the ear)
- Dizziness or loss of balance
- Difficulties with speech and swallowing
If the tumor grows large, it can cause facial numbness or weakness, or even paralysis, on the side of the face with the tumor. It can ultimately press against the brainstem and cause cerebrospinal fluid buildup in the brain, a dangerous condition called hydrocephalus.
What causes an acoustic neuroma?
The cause of an acoustic neuroma remains unknown in most cases. Acoustic neuromas appear related to a gene malfunction on the 22nd chromosome.
How is acoustic neuroma treated?
Treatment for acoustic neuroma will depend on the patient’s age and health condition and the tumor itself. If the tumor is small, no treatment may be necessary. Doctors may choose observation, and will monitor the acoustic neuroma to see if it grows over time. Younger patients and those with larger tumors may require traditional (open) surgery. Surgical removal carries risk of infection, spinal fluid leakage, heart complications and further damage to nearby nerves. For many patients, Gamma Knife stereotactic radiosurgery may be a preferred option to stop the growth of the tumor. Gamma Knife can also be used as a follow-up to surgical removal if it is not possible to remove the tumor completely without causing additional damage. Gamma Knife may also be used to treat regrowth after surgery, as regrowth occurs in about eight to 10 percent of cases. Neither surgery nor radiation can restore hearing already lost.
What is Gamma Knife treatment for acoustic neuroma?
Gamma Knife is a minimally invasive treatment with the precision of surgery. Gamma Knife uses highly targeted, high-dose radiation to destroy the DNA of tumor cells so they can no longer reproduce. At South Sound Gamma Knife, we perform leading-edge radiosurgery using the Leksell Gamma Knife Icon, the most current Gamma Knife technology available. The Icon uses 192 beams of Cobalt60 radiation that converge on a single, computer-mapped focal point. Surrounding tissue remains unharmed, and patients can remain awake for the procedure and go home the same day. The recovery process takes three to four months. Patients should expect hearing preservation, but not hearing improvement. No part of hearing loss will be restored.
What are the risks of Gamma Knife treatment for acoustic neuroma?
Post-treatment edema (swelling) can result in temporary hearing loss, cranial nerve damage (numbness) and fatigue.
Click here to learn more about what to expect with Gamma Knife to treat acoustic neuroma.
Please call our Gamma Knife Coordinator for more information or a referral for a patient consultation at (253) 284-2438 or toll free (866) 284-3353. We welcome out-of-town and out-of-state patients and do all we can to make your treatment visit comfortable.