Acoustic neuromas are noncancerous tumors. They grow on the nerve that connects the brain and ear. Because these tumors are benign, they do not spread to other body parts. However, they can grow large enough to damage important nerves.
According to the Acoustic Neuroma Association, acoustic neuromas appear in one out of every 50,000 people.
There is only one known risk factor for acoustic neuroma – having a parent with the genetic disorder neurofibromatosis type 2. However, the vast majority of these tumors appear spontaneously. They occur in people with no family history of the disease.
Scientists still do not understand why some people get these tumors. Some risk factors might include:
- loud noises.
- a parathyroid neuroma. This is a benign tumor of the thyroid.
- exposure to low levels of radiation during childhood
Small neuromas rarely have symptoms. Symptoms typically appear only when the tumor gets large enough to press on surrounding nerves. One of the most common symptoms of this condition is a gradual loss of hearing on one side of the head. This hearing loss usually happens slowly over time, but it can also start very suddenly. Vertigo, or dizziness, and ringing in the ears are common. These tumors can also cause facial numbness, weakness, and problems with balance.
Some less common symptoms include:
- problems with vision
- difficulty understanding speech
- pain in the face or ear
- numbness in the face or ear
If you experience hearing loss or other neurologic symptoms, it is important to keep track of them. This can help your doctor diagnose your problem.
The first step in diagnosis is a detailed history of your symptoms. If you have a neuroma, you will probably need a hearing test. You may need other tests as well.
- Brain stem auditory evoked response tests can check both neurological and hearing function.
- Electronystagmography detects changes in eye movement that may be caused by inner ear problems.
- MRIs and CT scans can give your doctor an image of the inside of your head.
Your age, level of health and tumor size will all affect your treatment.
Treatment is not always necessary. If you have a small acoustic neuroma, your doctor may just monitor its growth with regular MRIs. However, a lack of treatment can sometimes lead to a buildup of fluid within the brain. This life threatening condition is called hydrocephalus.
If you have a relatively small tumor, your doctor may try to stop its growth. This is done with stereotactic radiosurgery. In this procedure, radiation is applied to a small, specific area of your head. It is not invasive, but it is also very slow. It can take months or years to get rid of a tumor. That is why this procedure is usually only used for very small tumors. It can also be used when surgery is too risky or if residual tumors remain after surgery.
Surgery may be necessary if your tumor is very large or fast growing. You may also need surgery if your tumor is starting to approach a vital part of the brain. During surgery, the tumor can be removed either through the skull or through the ear itself. Recovery time ranges from a few days to several weeks.
This surgery can have many complications and risks. These include:
- complete loss of hearing
- weakened facial muscles
- ringing in the ears
- cerebrospinal fluid leaking from the incision
- problems with balance
- persistent headaches
It is important to talk to your doctor as soon as you start experiencing neuroma symptoms. That is the only way to preserve your hearing. Once lost, hearing will not return after treatment.