Gamma Knife Treatment for Acoustic Neuromas

Effective acoustic neuroma treatment with gamma knife

When symptoms from an acoustic neuroma, also called a vestibular schwannoma, such as dizziness, ringing, and hearing loss become severe, Gamma Knife treatment may be the best option. Despite its name, Gamma Knife is not a surgical procedure. During this type of stereotactic radiosurgery, surgeons use highly focused beams of radiation to kill the tumor cells and stop them from growing — without causing damage to surrounding tissue. For some acoustic neuroma patients, early intervention with Gamma Knife can alleviate the risks of hearing loss associated with a fast-growing acoustic neuroma, as well as the worry and follow-ups that are part of observation. Gamma Knife treatment provides 92 to 97 percent tumor control rates for acoustic neuroma patients after five years. The experienced Gamma Knife-certified neurosurgeons and radiation oncologists at Rocky Mountain Gamma Knife Center have treated more than 5,300 patients using this noninvasive procedure.


Watch a video to learn more about Gamma Knife treatment for acoustic neuromas and continue reading below to learn more.



What Is Gamma Knife Treatment?

How Gamma Knife Treats Acoustic Neuromas

Latest Research on Gamma Knife Treatment for Acoustic Neuromas

Outcomes and Benefits of Gamma Knife Treatment

Who Is a Candidate for Gamma Knife Treatment?

Preparing for Gamma Knife Treatment

Recovery From Gamma Knife Treatment

Follow-up After Gamma Knife Treatment

Why Choose Rocky Mountain Gamma Knife Center?

Does Insurance Cover Gamma Knife Treatment for Acoustic Neuromas?

How to Get Gamma Knife Treatment for Acoustic Neuromas



What is Gamma Knife Treatment?

Sometimes referred to as Gamma Knife surgery or stereotactic radiosurgery (SRS), Gamma Knife treatment is actually a noninvasive procedure that consists of a precisely targeted delivery of radiation beams. It has been used to successfully treat brain disorders since its introduction in 1967.

Gamma Knife treatment is often used for noninvasively treating acoustic neuromas. The treatment delivers one concentrated dose of irradiation to a small, acutely located intracranial volume through the skull, to the brain. Gamma Knife is preferred over other treatments for its accuracy, efficiency, and the exceptional responses generated from the therapy.

The precision of the Gamma Knife treatment ensures that only the targeted section of the brain is subject to radiation. Unlike other treatments, Gamma Knife allows the healthy tissue surrounding the area to remain unharmed. Because this is a noninvasive procedure, there is no incision, which significantly reduces the chance of infection, risk of bleeding, and recovery time — making it ideal for patients suffering from an acoustic neuroma.

Gamma Knife treatment is performed in many of the world’s top hospitals and clinics. Doctors perform around 50,000 Gamma Knife treatments each year. The treatment has been researched in thousands of peer-reviewed medical articles and garnered more acceptance than any other noninvasive treatment in this field.


How Gamma Knife Treats Acoustic Neuromas

Because acoustic neuromas are not cancerous, it is usually not necessary to remove the patient’s tumor unless it is causing symptoms. The goal of Gamma Knife treatment for acoustic neuromas is to kill the tumor cells by cutting off the blood supply to them. This stops them from growing and causing problems, such as permanent hearing loss. For acoustic neuromas up to 3 centimeters, treatment with Gamma Knife is usually recommended for long-term tumor control. (While Rocky Mountain Gamma Knife Center has treated a handful of lesions between 3 and 4 centimeters, these were carefully selected patients for whom other treatments were not an option.)

Latest Research on Gamma Knife Treatment for Acoustic Neuromas

Various studies have found that Gamma Knife treatment is effective in stopping acoustic neuromas from growing in 92 to 97 percent of cases. The most relevant research studies include:

Boari, N.; Bailo, M.; Gagliardi, F.; Franzin, A.; Gemma, M.; del Vecchio, A.; Bolognesi, A.; Picozzi, P.; Mortini, P. Gamma Knife radiosurgery for vestibular schwannoma: Clinical results at long-term follow-up in a series of 379 patients. Journal of Neurosurgery. December 2014.

Kaylie, D.M.; Gilbert, E.; Horgan, M.A.; Delashaw, J.B.; McMenomey, S.O. Acoustic neuroma surgery outcomes. Otology & Neurotology. September 2001.

Timmer, F.C.; Hanssens, P.E.; van Haren, A.E.; Mulder, J.J.; Cremers, C.W.; Beynon, A.J.; van Overbeeke, J.J.; Graamans, K. Gamma Knife radiosurgery for vestibular schwannomas: Results of hearing preservation in relation to the cochlear radiation dose. The Laryngoscope. June 2009.

Kang-Min Kim, MD; Chul-Kee Park, MD; Hyun-Tai Chung, PhD; Sun Ha Paek, MD; Hee-Won Jung, MD; Dong Gyu Kim, MD. Long-term outcomes of Gamma Knife stereotactic radiosurgery of vestibular schwannomas. Journal of Korean Neurosurgical Society. October 2007.

Rowe, J.G.; Radatz, M.W.R.; Walton, L.; Hampshire, A.; Seaman, S.; Kemeny, A.A. Gamma Knife stereotactic radiosurgery for unilateral acoustic neuromas. Journal of Neurology, Neurosurgery, and Psychiatry. November 2003.

Toshinori Hasegawa, MD; Shigeru Fujitani, MD; Shun Katsumata, MD; Yoshihisa Kita, MD; Masayuki Yoshimoto, MD; Joji Koike, MD. Stereotactic radiosurgery for vestibular schwannomas: Analysis of 317 patients followed more than 5 years. Neurosurgery. August 2005.

Myrseth, E.; Møller, P.; Pedersen, P.H.; Vassbotn, F.S.; Wentzel-Larsen, T.; Lund-Johansen, M. Vestibular schwannomas: Clinical results and quality of life after microsurgery or Gamma Knife radiosurgery. Neurosurgery. May 2005.

Yamakami, I.; Uchino, Y.; Kobayashi, E.; Yamaura, A. Conservative management, Gamma Knife radiosurgery, and microsurgery for acoustic neurinomas: A systematic review of outcome and risk of three therapeutic options. Neurological Research. October 2003.


Outcomes and Benefits of Gamma Knife Treatment

Various studies have documented that Gamma Knife treatment for acoustic neuromas controls tumor growth in 92 to 97 percent of patients after five years. Two of the first patients treated at Rocky Mountain Gamma Knife Center in 1994 still receive regular MRI scans that show their tumors shrank after treatment and have not grown larger since.

Benefits of Gamma Knife treatment for acoustic neuromas include:

  • Extreme precision: Allows a powerful dose of radiation to be delivered with no or minimal damage to healthy surrounding tissue and cranial nerves.
  • No incision: No incision means there is virtually no risk of bleeding or infection, and no risk of leakage of cerebrospinal fluid.
  • Few side effects: Low risk of permanent facial weakness and rare need for follow-up surgery to restore proper facial functioning, including eyelid closing, excessive tearing, or dry eye.
  • One-time treatment: Performed in a single session, typically on an outpatient basis and only rarely requiring an overnight stay.
  • No downtime: Patients can return to their normal activities almost immediately, with no rehabilitation necessary.
  • Repeatable: Treatment potentially can be repeated without risk if the tumor did not respond as expected.
  • Low cost: Gamma Knife treatment is covered by Medicare and most insurance plans, and Gamma Knife treatment costs much less than traditional treatments.


Who Is a Candidate for Gamma Knife Treatment?

The majority of acoustic neuroma tumors up to 3 centimeters qualify for Gamma Knife treatment. Gamma Knife treatment is a good option for many acoustic neuroma patients because no general anesthesia is required.

Gamma Knife radiosurgery has long been recognized as the only option for many patients who, for health reasons, may not be candidates for conventional open surgeries. It also is a good option for patients who want a noninvasive treatment with little to no recovery time or side effects, or who cannot tolerate general anesthesia.

At Rocky Mountain Gamma Knife Center, our specialists review each case individually to determine the best course of treatment. By looking at your medical history and discussing symptoms and treatment goals, the team can assess whether you are a candidate for this procedure.


Preparing for Gamma Knife Treatment

After the initial consultation, eligible acoustic neuroma patients will undergo pre-procedure imaging to establish exactly where the radiation dose will be targeted. Most patients will be able to schedule an appointment to meet with one of Rocky Mountain Gamma Knife Center’s neurosurgeons within two to three weeks of contacting the office. Prior to the Gamma Knife treatment, patients are asked not to eat or drink anything after midnight the day before the treatment.

Due to the noninvasive nature of the procedure, Rocky Mountain Gamma Knife Center patients are usually able to go home the same afternoon as their procedure.

Some important information about the Gamma Knife treatment procedure:

  • A box-shaped frame will be put around the patient’s head to prevent any movement. The frame will be attached to the patient’s head, and a topical numbing medication may be used.
  • The patient will be awake throughout the entire procedure, and no general anesthesia is required. Patients may request a light sedative for relaxation if desired.
  • The patient will not be aware of the administration of radiation, as it is not visible, audible, or painful.

The duration of the actual Gamma Knife treatment depends on the size, shape, and location of the tumor. But it typically takes an hour.


Recovery From Gamma Knife Treatment

When the Gamma Knife radiosurgery is complete, the box-shaped frame will be removed and a sterile dressing will be applied to the targeted area. Then the patient will be transferred to UCHealth Hospital to be observed for a few hours. In the hours following the procedure, the local anesthetic will wear off and the patient may experience pain comparable to a headache. Headache medication will be recommended to the patient shortly after arriving to UCHealth Hospital. Before the patient is discharged, the team will ensure that he or she is experiencing relatively low pain and can tolerate food without nausea.

Patients receiving Gamma Knife treatment for an acoustic neuroma spend eight to 10 hours at the center and hospital. Occasionally, a patient may be admitted to the hospital for an overnight stay based on his or her physician’s orders.

All patients must have a designated driver to take them home after the procedure. Little recovery is needed. While many patients are able to return to work and resume normal activities the next day, some may feel tired and want to rest afterward. 

Learn more about recovery from Gamma Knife radiosurgery for acoustic neuromas in this video featuring an experienced Gamma Knife nurse.


Follow-up After Gamma Knife Treatment

Many patients can return to work the next day and resume normal activities. The Rocky Mountain Gamma Knife team will decide how many follow-up appointments are necessary on a case-by-case basis.


Why Choose Rocky Mountain Gamma Knife Center?

Since carrying out the region’s first Gamma Knife surgery in 1993, the center has been a leader in offering Gamma Knife treatment for more than 30 brain conditions, including acoustic neuromas, as well as benign and metastatic brain tumors. After treating more than 5,300 patients, Rocky Mountain Gamma Knife Center has established itself as the most experienced center in the region for stereotactic radiosurgery.

Rocky Mountain Gamma Knife Center has an expert team of neurosurgeons and radiation oncologists with more than 200 combined years of experience in treating malignant and benign brain diseases and neurovascular disorders. The center also is a recognized national leader in treating the debilitating facial pain known as trigeminal neuralgia.



Learn more about Rocky Mountain Gamma Knife Center here.


Does Insurance Cover Gamma Knife Treatment for Acoustic Neuromas?

Radiosurgery with Gamma Knife is covered by most insurance plans, and our staff can help you coordinate preauthorizations and understand other coverage questions.


How to Get Gamma Knife Treatment for Acoustic Neuromas

If you have questions about Gamma Knife treatment for acoustic neuromas or would like to schedule an appointment with one of our neurosurgeons to see if you qualify for Gamma Knife radiosurgery, please fill out our online form or call 303-366-0099 to speak with one of our expert Gamma Knife nurses.


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Learn more about acoustic neuromas: click on links below

Overview of Acoustic Neuromas

Treatment Options for Acoustic Neuromas



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