An acoustic neuroma, also known as a vestibular schwannoma, is a tumor of the hearing and balance nerve complex in the brain. They are rare, and account for less than 10% of all brain tumors. The tumor involves an area of the brain and ear called the lateral skull base; an acoustic neuroma can range in size, and it can cause a variety of troublesome symptoms related to hearing and balance.
It is important to note that although the diagnosis of a brain tumor can cause significant anxiety, acoustic neuromas are noncancerous and grow very slowly. This means that immediate treatment is rarely necessary.
What are the most common symptoms?
Acoustic neuromas can cause you to experience a variety of symptoms. In general, the first thing you may notice is hearing loss in one ear greater than the other, ringing in the ears (tinnitus), and/or dizziness or imbalance (acute or chronic). These symptoms can range from mild to very distressing and bothersome. It is important to note that these symptoms are not related to the size of the tumor. Some people can have a very small tumor with significant hearing loss and imbalance, while other people can have very large tumors with few symptoms. If you are experiencing any or all of these symptoms, you should seek the attention of your physician.
How are acoustic neuromas diagnosed?
If symptoms of hearing loss, tinnitus, or imbalance are present, you will likely be referred to an ear, nose, and throat specialist (ENT) for evaluation. Commonly, with these symptoms you will be asked to undergo a hearing test. If you are dizzy, additional balance testing may be performed. If there are any abnormalities on either of these tests that demonstrate unequal function (asymmetrical hearing loss), you may undergo imaging of the inner ears and head with an MRI to check for an acoustic neuroma. An MRI can help accurately diagnose an acoustic neuroma because the characteristics of these tumors look particularly unique compared to other brain tumors.
What if the MRI doesn’t show an acoustic neuroma?
Because acoustic neuromas are rare, MRI scans are often normal in patients with symptoms of hearing loss, tinnitus, and dizziness, and it is very unlikely that you have an acoustic neuroma with a normal MRI. However, this does not mean that you do not have the symptoms, and additional testing of these symptoms may be necessary. Talking to your doctor about symptom management is important, no matter what the MRI scan reveals.
What is the next step if I am diagnosed with an acoustic neuroma?
If you are diagnosed with an acoustic neuroma, the amount of information you receive can seem overwhelming. It is important to know that decisions for treatment rarely need to be made immediately. After diagnosis, your next step may involve referral to a specialist.
You should expect a team of specialist doctors to be involved in your care,