It’s likely that hearing loss can just be a part of aging. But, sometimes it could be due to a more serious issue like an acoustic neuroma.

To learn more, we reached out to Rick A. Friedman, MD, PhD, the director of the USC Acoustic Neuroma Center at Keck Medicine of USC.

Dr. Friedman explained the most important things you need to know about acoustic neuroma:

What is acoustic neuroma?

An acoustic neuroma, more correctly called a vestibular schwannoma, is a rare benign tumor originating from the outer sheath of the balance nerve. They are usually slow growing and account for approximately 7.5 percent of brain tumors.

How do you get it?

The cause of acoustic neuroma is not well understood. For most acoustic neuromas, the cause at the level of the cellular machinery is the failure of a “governor” gene to exert its effect in suppressing the growth of Schwann cells – those cells responsible for coating nerve fibers with insulation. The result is “wart-like” growth of these cells to produce the neuroma.

The only environmental exposure that has been definitively associated with an increased incidence is radiation exposure to the head. No evidence currently exists for an association between cell phone use and the development of these tumors.

For the most part it is not an inherited disease; however, 5 percent of cases are associated with a genetic disorder called neurofibromatosis type 2. The vast majority of tumors are sporadic (nonhereditary).


Symptoms can be associated with the size of the tumor but this is not always consistent. The most common first symptom is one-sided hearing loss and ringing or fullness in the ear. Individuals may also experience balance issues, dizziness and numbness or tingling on one side of their face.

When to consider treatment:

If you have been diagnosed with an acoustic neuroma, the most important thing is to first consult with a highly experienced program that can assess your unique needs and identify the care plan that is right for you. This is based on multiple factors such as tumor size, existing level of hearing, symptoms and age. After a thorough review of your individual case with an AN expert, you can then make an informed decision on how to treat your tumor.

Treatment options:

Depending on the size of the tumor, the age and medical condition of the patient, various procedures may be done.

  • Microsurgery

Surgery is done in an operating room where our skull-based team uses the latest microsurgical approaches and equipment. There are three main microsurgical approaches for the removal of an acoustic neuroma. The approach used for each individual patient is based on factors such as tumor size, location, skill and experience of the surgeon. The surgeon and the patient should thoroughly discuss the reasons for a selected approach.

  • Radiosurgery

With radiosurgery, the goal is to stop the growth of your tumor without injuring important structures around the tumor. This does not lead to removal of the tumor, but may potentially stop further growth or shrink it over time. At medical centers like Keck Medicine of USC, we use the gamma knife or the cyberknife to perform these radiation treatments. Radiosurgery is generally reserved for tumors under 2.5cm in diameter. For young, healthy candidates with active lifestyles and a desire to preserve their hearing, we typically recommend surgery as opposed to radiation.

  • Watch and Wait or Observation

A “watch and wait” strategy can be a good start for you if your tumor is small and you are experiencing very minimal symptoms. This approach generally involves a second MRI in 6 months and annually provided there is no growth, and /or symptoms have not changed.

What treatment does:

The goal of treatment is to stop the degeneration of surrounding cranial nerves. If you are a candidate for hearing preservation, the goal is to preserve your hearing to the level it is at when you are first diagnosed, but it does not recover your hearing to a prior state. Additionally, our top priority is always on maintaining facial nerve function and drastically minimizing the need for any future treatment.

Why Keck Medicine of USC:

According to the University Health System Consortium (UHC), at the USC Acoustic Neuroma Center at Keck Medicine of USC, we are ranked number one in volume and outcomes for academic centers. We also demonstrate the shortest hospital stays in the nation. While the average hospital stay is at 2.8 days, ours is at a little over two days. Full recovery takes anywhere from 6-8 weeks but can vary with each patient. This is why our program provides full support and resources to our patients for as long as they need it!

When you choose the USC Acoustic Neuroma Center, our patient navigator contacts you to provide assistance throughout your treatment. She is an experienced former patient who will be able to share details of what to expect throughout the process, how you will feel and she can help coordinate the logistics of your multi-disciplinary care. She is also there to provide emotional support.

Patients who go through treatment tend to experience a variety of symptoms and at times a very emotional response as they adjust to their new normal, but one of the beauties of the USC Acoustic Neuroma Center is our multidisciplinary approach and the commitment that the hospital, the university and the school of medicine have made to our program. We help our patients psychologically and physiologically with early intervention, education and ongoing support from our team of experts.

After surgery, our patients are up and out of bed early with a physical therapy team that works with acoustic neuroma patients on a daily basis. This team specializes in vestibular disorders and are experts at helping to restore balance function. Their help will allow you to be discharged earlier. We then follow up with postoperative physical therapy sessions and patient education to help you get back on track to your normal daily routines in life.

Our team remains in contact with our patients for life if necessary, or for as long as they need us. We have created a program with an infrastructure that supports multiple disciplines being involved in the treatment of our patients. We are completely invested at all levels in the care of acoustic neuroma patients, research and setting the standard of care for patient outcomes.

If you suffer from hearing loss or ringing of the ears, make an appointment with a neurologist. To learn more about USC Acoustic Neuroma Center, visit

To schedule an appointment, call (800) USC-CARE (800-872-2273) or visit