Acoustic Neuroma: Causes, Symptoms, Diagnosis, Treatment, and Prevention
An acoustic neuroma is a noncancerous tumor that grows on the vestibular nerve, which connects the inner ear with the brain, which is called the vestibular nerve. Hearing loss, ringing in the ear, and balance problems can result from pressure from an acoustic neuroma.
Causes of Acoustic Neuroma
In some cases, acoustic neuromas may be caused by a problem with a gene on chromosome 22 that produces a tumor suppressor protein that controls the growth of Schwann cells covering the nerves. It is inherited in people with a rare disease called neurofibromatosis type 2. It is common for patients with neurofibromatosis type 2 to grow tumors on the hearing and balance nerves.
Symptoms of Acoustic Neuroma
Acoustic neuroma symptoms are often easy to miss and can take years to develop. They can be caused by the tumor's effects on the hearing and balance nerves. An acoustic neuroma can also affect nearby nerves that control facial muscles, the facial nerve, and sensation, the trigeminal nerve. An acoustic neuroma can also affect blood vessels or brain structures.
Common symptoms of an acoustic neuroma include:
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Hearing loss, usually gradually over months to years. In rare cases, hearing loss can be sudden. Hearing loss usually occurs on one side or is worse on one side.
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Tinnitus: ringing in the affected ear.
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Loss of balance or not feeling steady.
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Dizziness.
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Facial numbness and, very rarely, weakness or loss of muscle movement.
Rarely, an acoustic neuroma may grow large enough to compress the brainstem and become life-threatening.
Diagnosis of Acoustic Neuroma
A thorough physical examination, including an ear exam, is often the first step in diagnosing and treating acoustic neuroma. Acoustic neuromas can be difficult to diagnose in the early stages because their symptoms may be easy to miss and develop slowly over time. In addition to hearing loss, many other middle and inner ear problems may also cause similar symptoms.
After asking questions about your symptoms, a member of your health care team conducts an ear exam. You may need one or more tests to confirm the condition:
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This type of hearing test is performed by an audiologist, who specializes in hearing. It involves directing sounds to one ear at a time. The audiologist then presents sounds of various tones. Each tone is repeated at faint levels to determine when you are barely able to hear it. The audiologist may also present different words to test your hearing.
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An acoustic neuroma can be diagnosed using magnetic resonance imaging (MRI) with contrast dye. If an MRI scan is not available or you cannot have an MRI scan, you may be able to undergo a computerized tomography (CT) scan. CT scans may miss small tumors, however.
Treatment of Acoustic Neuroma
Acoustic neuroma treatment depends on several factors:
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The size and growth rate of the tumor
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Your overall health
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Your symptoms
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Your preferences
There are three main treatment options for acoustic neuroma: monitoring, surgery or radiation therapy.
Monitoring
You and your health care team may decide to monitor an acoustic neuroma if it is small and isn't growing or if it is growing slowly. This may be an option if you're over 60 years old or if you aren't a good candidate for more aggressive treatment. To determine if your tumor is growing or causing worse symptoms or other problems, you will have regular imaging and hearing tests every 6 to 12 months. If needed, surgery or radiation therapy may be needed.
Surgery
You may need surgery to remove an acoustic neuroma if it’s continuing to grow rapidly; very large; causing severe symptoms; compressing vital structures; affecting your vision; causing facial weakness; causing severe dizziness; causing severe tinnitus; causing severe hearing loss; causing severe balance problems; causing severe facial numbness; causing severe facial weakness; causing severe dizziness; causing severe tinnitus; causing severe hearing loss; causing severe balance problems; causing severe facial numbness; causing severe facial weakness; affecting your vision; compressing vital structures; affecting your vision.
Prevention of Acoustic Neuroma
There is no sure way to prevent acoustic neuroma, but some steps may help reduce your risk or slow down its growth. These include:
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Avoiding exposure to high-dose ionizing radiation, such as from X-rays or nuclear accidents. Radiation may damage the DNA of the cells that form the tumor.
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Avoiding smoking, which may increase your risk of developing acoustic neuroma and other types of cancer.
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Eating a healthy diet that includes plenty of fruits, vegetables, whole grains, lean proteins and healthy fats. A balanced diet may help lower your risk of developing acoustic neuroma and other chronic diseases.
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Getting regular check-ups and screenings for any signs or symptoms of acoustic neuroma or other ear, nose and throat problems. Early detection and treatment may improve your chances of recovery and prevent complications.
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Following your doctor’s advice and recommendations for managing your condition if you have an acoustic neuroma. This may include taking medications, undergoing surgery or radiation therapy, or having regular monitoring tests.
Conclusion
Hearing and balance nerves are affected by a benign tumor known as acoustic neuroma. The exact cause of acoustic neuroma is not known, but it may be related to a genetic mutation or exposure to radiation. It can cause various symptoms, including hearing loss, tinnitus, dizziness, facial numbness, and weakness. Acoustic neuroma can be difficult to diagnose because it mimics other ear conditions. Acoustic neuromas can be treated using monitoring, surgery, or radiation therapy, depending on the size, growth rate, and location of the tumor.
If you notice any changes in your hearing or balance abilities, it is important to seek medical attention. Acoustic neuroma is generally not life-threatening, but it can affect your quality of life and daily activities. By avoiding harmful factors such as radiation and smoking, you can also lower your risk of developing acoustic neuroma or slow down its progression.
