Acoustic Neuroma | vestibular schwannoma | Ear, Nose, and Throat Disorders

 

Acoustic neuroma is an ear, nose, and throat disorder which can be generally called vestibular schwannoma that can be noncancerous and it can be a slow-growing tumor that typically develops on the vestibular nerve which is leading from your inner ear to your brain. 

These main nerve branches will directly attack your balance and hearing levels and also they give a lot of pressure from an acoustic neuroma(tumor) which can cause loss of hearing sense, ringing in your ear and unsteadiness.

Acoustic neuroma or vestibular schwannoma typically arises from the cells called Schwann which are covering this nerve and it starts to grow slowly or not at all. In some rare cases, it might grow faster and become huge enough to press against the brain, then it might interfere with your more vital functions of your body.

Generally, treatments for this acoustic neuroma disorder such as regular monitoring, radiation and surgical removal.

Causes

Typically, the cause of acoustic neuromas will be directly linked to a problem in a gene on chromosome 22. Generally, this type of gene in your body naturally produces a tumor suppressor protein which can be helpful to the growth of Schwann cells which are covering the main nerves in your body.

Researcher’s do not know the exact cause of this problem with genes. Most of the cases with acoustic neuroma, there can be no known cause of it. This problematic gene can also be inherited in neurofibromatosis type 2, which is a rare type of disorder that generally involves the growth of tumors on the main nerves of hearing and balance on both sides of your head called bilateral vestibular schwannomas.

Symptoms

One of the common symptoms of this disorder is hearing loss in one ear called unilateral. This can happen to about 90% of people with acoustic neuroma disorder.

Some symptoms that can occur in early stages are:

• Tinnitus means Ringing in the ears

• Loss of balance

• Vertigo which means you feel sensation that you or your environment is moving

If the tumor grows, you might experience some other symptoms which includes:

• Blurry or double vision.

• Facial numbness, weakness, spasms, pain, or paralysis.

• Taste changes.

• Headaches.

• Nausea and vomiting.

• Swallowing difficulty.

Symptoms of this disorder might be similar symptoms of other ear problems. This similarity makes it challenging you to diagnose this disorder. Talk to your doctor if you notice any changes in your hearing level.

Diagnosis

Your healthcare professional asks about your symptoms and then does a physical examination. Followed this, you will have a series of hearing and balance tests and scans which includes:

• Audiogram which helps to check hearing ability.

• Electronystagmography, which helps to test the balance and record your eye movement  to check how your nerves of ears and eyes are functioning.

• Auditory brainstem response - which measures how your hearing nerves respond to outside sound and helps to check your brainstem function.

• MRI and CT scans which helps to locate the tumor and measure its size.

Treatment

Typically, treatments depend on the tumor’s size and its location and your age and also your overall health. You and your healthcare professional should make a decision, if you want to watch the tumor without treatment, and you can use a  radiation treatment to stop it growing or trying to remove it by surgery.

Usually, many of the acoustic neuromas are small and grow very slowly. Small tumors will have few symptoms or not at all. You might be watched for changes particularly in aged people. And also suggest you do regular MRI scans.

If you not treat the acoustic neuromas, it may:

• Damage the main nerves which can be involved in hearing and balance

• Give you more pressure on brain tissues

• Harm the main nerves which is responsible for both movement and feeling in the face

• Hydrocephalus which is leading to a buildup of fluid in the brain for very large tumors

Acoustic neuroma can be removed for 

• Larger tumors

• Tumors that are causing severe symptoms

• Slow growing tumors 

• Tumors which is pressing on the brain

Surgery or a radiation treatment will be done to remove the tumor and it can prevent other nerve damages. Hearing loss can be preserved sometimes which can depend on the type of surgery performed.

Removing an acoustic neuroma will damage the nerves. This will lead to hearing loss or weakness in the face muscles. When the tumor is large, this damage will likely occur more.

Post-Surgical Complications

Your provider will discuss with you about your post complications and how to treat and manage them. Some of the issues that might be arise after the surgery which includes:

• Due to tumor removal surgery, Hearing loss in one ear can happen.

• Tumor growing back.

• Tinnitus means ringing in the ear.

• CSF means Cerebrospinal fluid leaks.

• Infection of the incision or meningitis.

• Dizziness, balance problems, headaches.

• Weaken your facial nerves, or it may lead to temporary or permanent facial paralysis.

• Eye issues which include dry eyes, double vision, difficulty closing eyelids.

• Taste issues, dry mouth, trouble swallowing.

Frequently Asked Questions

Q1. What was your first symptom of acoustic neuroma?

Ans: The most common presenting symptom was a unilateral hearing loss.

Q2. How is acoustic neuroma caused?

Ans: For most acoustic neuromas, the cause at the cellular level is the failure of a "governor" gene to suppress the growth of Schwann cells.

Q3. Is acoustic neuroma curable?

Ans: Many acoustic neuromas can be completely removed by surgery. 

Q4. Who is at risk for acoustic neuroma?

Ans: The only known risk factor for acoustic neuroma is having a parent with the genetic disorder neurofibromatosis 2 (NF2).

Q5. Is acoustic neuroma a brain tumor?

Ans: An acoustic neuroma, also known as a vestibular schwannoma, is a tumor of the hearing and balance nerve complex in the brain.