Acoustic neuroma is a benign tumor that grows slowly from the vestibule-cochlear nerve, which is responsible for hearing. Acoustic neuroma is linked to an abnormal protein, and it is characterized by loss of hearing, vertigo, ringing sounds in the ears (tinnitus), difficulty with balance, feeling pressure in the ears, headaches and possible vision abnormalities. Other characteristics of acoustic neuroma is inability to understand speech and when the tumor advances in size it can cause numbness of the face and possibly could even cause facial paralysis.
Some individuals have no symptoms at all because the tumor is so small; the tumor is usually a slow growing, and sometimes they don’t know they have acoustic neuroma until their symptoms send them to the doctor for a checkup. For instance, hearing loss is usually gradual in a person with acoustic neuroma; therefore, loss of hearing might not be noticed right away.
Acoustic neuroma is usually found in women between the ages of 30 and 60. Though this disorder isn’t cancerous, it is a potentially devastating disorder if the tumor grows enough to put pressure on a nerve.
When to see a physician
You should see a physician when you notice symptoms that you didn’t have before. It is important to get an early diagnosis, to track the size of the tumor. The tumor, in a person with acoustic neuroma, could grow large enough to cause life-threatening pressure inside of the head.
Diagnostic tests for acoustic neuroma
Auditory Brainstem Response – The doctor will order diagnostic tests, such as an Auditory Brainstem Response (ABR), also known as Brainstem Evoked Response Audiometry (BSER), which evaluates the function of the cranial nerves and brain functions that are associated with hearing. Electrodes are placed on the scalp and on the ear lobes. The test generates a tone and a computer can record and measure whether or not the neurons responsible for hearing are functioning.
Magnetic resonance imaging or computerized tomography scan – An MRI or CT scan may be ordered to confirm or rule out the presence of a tumor. If an acoustic neuroma is present the MRI or CT scan will provide cross section images of the tumor. The doctor will be able to detect and record the dimension of the acoustic tumor.
Audiometry – An audiometry test is a hearing test. You put earphones on and an audiologist (hearing specialist) delivers sounds at various pitches, tones and volumes. Thus, the audiologist will be able to evaluate how well you can hear.
Electronystagmography – The ENG test is done to measure a certain type of rhythmic eye movement, called nystagmus, which is present in individuals with certain types of inner ear problems. This test takes about 90 minutes to complete. Electrodes are placed around the eyes; this test works something like an electroencephalogram, but it works to detect eye movements when warm and cold water are introduced into the ear canal. This test may also involve tracking lights or images on a computer screen.
Your doctor may elect to just watch the tumor. If the tumor’s size remains about the same or is growing very slowly, the doctor may decide to watch and wait. You may need to have scans and other tests periodically to track the growth of the tumor. Other treatment options may include gamma-knife radiosurgery and surgical removal of the tumor.
Radiosurgery – This is a noninvasive treatment that involves delivering gamma rays precisely to certain spots on the tumor. The doctor will numb your scalp and then attach a special frame to your head. This frame will allow the doctor to target the tumor without causing radiation damage to the nearby nerve.
Acoustic neuroma surgery – Surgical removal of the acoustic neuroma is done while preserving nerve function. This surgical procedure is done under general anesthesia. An incision is made on the scalp on the side of the head where the tumor is located. A small hole is drilled into the mastoid bone of the skull, so the surgeon has access to remove the tumor. After the surgery is complete, the doctor takes some adipose (fat) tissue from the abdomen and plugs the hole with it. Then the scalp is sutured back into place.
You may have some questions about the doctor who will treat you for acoustic neuroma. It’s a good idea to keep paper and pen handy to jot down the questions that come to mind. You may have questions on how experienced your doctor is with acoustic tumors. Whatever questions you have, write them down so you can ask your doctor at your next visit. Most people have questions and then forget them when they get to the doctor’s office, so write the questions down beforehand.