Acoustic Neuroma

Treatment

The treatment of acoustic neuromas is complex and requires a sophisticated, experienced and well-coordinated team of medical providers. At Mayo Clinic, the team may include these physicians:

• A neurologist (a doctor who specializes in diseases of the nervous system)
• An otologist (a doctor who specializes in the treatment of ear diseases)
• A neurotologist (a surgeon who specializes in diseases of the ear)
• A neurosurgeon (a brain surgeon)
• A radiologist (a doctor who specializes in interpreting medical images)
• A radiation oncologist (a doctor who specializes in radiation therapy)
• A neuro-oncologist (a physician who specializes in the treatment of brain tumors and other types of nervous system tumors)

At Mayo Clinic, specific treatments are determined by a patient's medical team based on:

• The patient's age, overall health and medical history
• The size and location of the tumor
• Information obtained from imaging tests or scans
• The patient's tolerance for specific procedures or therapies
• The patient's opinion or preference

Three treatment options are available for acoustic neuromas:

• Observation
• Microsurgical removal or reduction of the tumor
• Stereotactic radiation therapy (radiosurgery)

Observation

Acoustic neuromas are sometimes discovered by physicians while evaluating a patient for another medical condition, or when the tumor is very small with subtle symptoms. Because the tumors are slow-growing, if discovered when they are very small, careful observation over time may be appropriate for some patients.

A small tumor diagnosed in an elderly patient may require only observation of its growth rate, if disabling symptoms are not present. If the tumor likely will not need to be treated during the patient's normal life expectancy, treatment and its potential risks and complications can be avoided. Some tumors don't appear to grow at all.

Observation also may be the preferred therapy for those who have a tumor in their only hearing ear or better-hearing ear. In such cases, growth is monitored and treatment is considered only if hearing is lost or the tumor size becomes life-threatening.

In these patients, magnetic resonance imaging (MRI) of the head is done periodically to monitor tumor growth. If there is no growth, observation is continued. If the tumor is growing, however, treatment may become necessary.

Microsurgical Removal

The goal of surgery is to remove the tumor and avoid any new neurologic deficits such as facial weakness or hearing loss. Success in achieving these goals depends a great deal on the tumor's size and configuration and the patient's hearing status prior to surgery.

Microscopic surgery for acoustic neuromas is done under general anesthesia. Usually, patients stay in the hospital four to five days after surgery.

Several surgical approaches can be used to remove acoustic neuromas. The choice depends on the location, tumor size, the patient's hearing level and the surgeon's skill and experience.

Each approach has advantages and disadvantages, but excellent results have been achieved in all approaches. The surgeon and patient should have a thorough discussion before selecting the approach.

Partial Tumor Removal

Some patients and their surgeons prefer partial removal of an acoustic neuroma, especially if the tumor is large. This decision includes the understanding that more surgery or stereotactic radiosurgery may be needed in the future.

The resulting smaller tumor may not threaten the patient's health and may preserve hearing in the affected ear. The probability of any facial nerve dysfunction also may be reduced as a result of partial removal. However, hearing loss is a risk with partial removal. Periodic MRI scans are important to detect potential growth of the remaining tumor.

Stereotactic Radiosurgery

Stereotactic radiosurgery precisely delivers radiation to a tumor in one session, usually performed as an outpatient procedure using local anesthesia. No restrictions follow radiosurgery, and most patients can return to work or normal activities within 48 hours. The goal of stereotactic radiosurgery is to stop tumor growth.

Sometimes, during brain surgery to treat acoustic neuromas, not all of the tumor can be safely removed and some remains. Radiosurgery is often used after surgery to treat remaining tumor tissue.

Sometimes during brain surgery to treat acoustic neuromas not all of the tumor can be safely removed and some must be left behind. Radiosurgery is often used after surgery to treat remaining tumor tissue.

Treatment Results

See summaries of Mayo Clinic published reports on results of Gamma Knife™ treatment (one method of stereotactic radiosurgery) on the following topics:

• Comparison of microsurgical resection and stereotactic radiosurgery
• Enlargement of acoustic neuromas after stereotactic radiosurgery
• Patient choice in treatment of acoustic neuromas
• Lower radiation dose lowers risk of facial neuropathy