Acoustic neuroma, also known as a vestibular schwannoma, is a rare condition when a tumor develops on the main nerve leading from the inner ear to the brain. It can cause hearing problems and, if left untreated, serious medical conditions.
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There are two types of acoustic neuromas: a sporadic form which is the most common, and NF2 which is an inherited disorder. The cause of an acoustic neuroma is unknown and there are no risk factors, except in a very small number of cases, so we can say it appears spontaneously.
What we do know, is that exposure to high doses of radiation, especially to the head and neck, is one factor that causes an acoustic neuroma, that it affects women more often than men, between the ages of 30 and 60, and it can be rarely found in children. Acoustic neuromas affect 1 in 100,000 people.
Talking about symptoms, hearing loss in one ear is the first symptom in 90 percent of cases, and other symptoms are ringing in the ears and dizziness. Those, early symptoms usually associated with aging, can be similar to those that usually appear in older people and the real condition may go unnoticed at first.
The good news is that this type of tumor doesn't spread to other organs. Another good news is that if someone has a small tumor that doesn't press the nerve too much, there may be no symptoms at all.
However, if the pressure is too strong, hearing can fluctuate and be better then worse then better again, and it can be followed by a feeling of fullness. In some cases, the patient can have hard time understanding speech. When talking about balance, our body is smart enough to adapt to problems with the nerve and since the tumor grows slowly it learns how to compensate and the patient stays in balance.
Since there is almost always the bad news present, that's the case in acoustic neuromas too. If an acoustic neuroma becomes too large, it can press cranial nerves and that leads to complications such as facial numbness, weakness or even paralysis. Numbness or tingling can come and go but a very unpleasant condition may be swallowing difficulty.
If an acoustic neuroma grows so big to press the brainstem, it can prevent the normal flow of cerebrospinal fluid. Since the fluid can't flow between the brain and spinal cord, the effect is hydrocephalus and then the patient has a number of symptoms, from headaches to bad movement coordination to mental confusion. If an acoustic neuroma presses against the little brain, the vital body functions such as blood pressure or heart rhythm regulation can be compromised, and that can be deadly.
When to see the doctor? If you have hearing loss in one ear, ringing, or trouble with your balance, you should go and make some tests. With simple hearing test, magnetic resonance imaging (MRI) or computerized tomography (CT) scans, the doctor can confirm what is going on and prevent more serious complications.
The treatment goes in three directions: it can be simple observation if the tumor does not cause major health problems, or the doctor may recommend surgical removal of the tumor, and radiation can be used to stop the tumor from growing.
Now, surgery and radiation are serious procedures and they may have some side effects and bad sides. Radiation therapy may take from weeks to years and tumor can start to grow again after the therapy is done.
In a case of surgery, the facial nerve may be damaged and sometimes the surgeon must remove portions of the facial nerve and that results in facial paralysis that can be temporary or permanent. Facial weakness is a problem because it leaves an eye vulnerable to damage of the cornea and that can lead to blindness. In that case, the patient should use artificial tears to keep the eye moist.
However, with modern surgical procedures, the outcomes of surgery for acoustic neuromas have improved greatly and if the condition is diagnosed early it can be treated very successfully. ■