Learning you may have a brain tumor can be overwhelming. However, educating yourself about your condition and treatment options enables you to play an active role throughout the process. This can help you feel more confident in conversations with your doctor, setting your mind at ease as you move forward.
If your doctor suspects you have an acoustic neuroma, he or she will likely recommend an MRI to aid in finalizing your diagnosis. You may wonder why this is necessary or what information an MRI can provide about your condition. The following will help you better understand the cause of acoustic neuroma and how an MRI can help doctors make a definitive diagnosis.
Understanding Acoustic Neuroma
An acoustic neuroma (also called a vestibular schwannoma) is a benign brain tumor that develops from the vestibulocochlear nerve, or the eighth cranial nerve. Cranial nerves are paired, which means you have one on each side of the brain. However, most acoustic neuromas only occur on one side of the body. The vestibulocochlear nerve transmits information about hearing and balance, which accounts for the symptoms you may be experiencing.
Symptoms of Acoustic Neuroma
Though an acoustic neuroma is benign, this does not mean it is harmless. These tumors can grow large enough to impinge on surrounding structures, like nerves and blood vessels. Symptoms can also vary depending on the location of the tumor along the vestibulocochlear nerve. Common symptoms of acoustic neuroma include:
- Hearing loss or ringing in one ear
- Double vision
- Difficulty with balance and/or walking
- Facial weakness or numbness
- Hoarseness or difficulty swallowing
- Fluid build-up on the brain (hydrocephalus)
Diagnosing Acoustic Neuroma
If your doctor suspects an acoustic neuroma, he or she may test your hearing and examine your ear to evaluate any hearing loss. However, that only provides so much information. A definitive diagnosis will typically require some sort of diagnostic imaging, such as a computed tomography (CT) scan or magnetic resonance imaging (MRI). A CT scan uses multiple x-rays to create an image, while an MRI uses magnetic fields and radio waves. Each provides different types of images and, as a result, different information.
According to a recent study published in the American Journal of Neuroradiology, MRIs are now the standard of care for diagnosing acoustic neuroma, though a CT can be helpful to diagnose changes to bony tissues. However, MRIs provide higher contrast resolution, making them a more helpful tool for diagnosing an acoustic neuroma, surgical planning, and follow-up after treatment.
What Does a Doctor Look For in an Acoustic Neuroma MRI?
When your doctor reviews your MRI, it will help provide information about the size, location, and characteristics of your tumor. This includes whether your tumor is pressing on other structures like the brain stem and whether there is extra fluid on the brain (hydrocephalus). This information will help your doctor determine an appropriate treatment plan for your individual case.
A trained specialist will interpret your MRI, which will be what’s called T1 or T2 weighted. These are different imaging modalities where different substances, like fat cells (which surround nerves) or air, show up as dark or bright. An acoustic neuroma will have a certain appearance that differentiates it from other pathologies. This appearance, the tumor location, and your symptoms will all help lead to a formal diagnosis.
Treating Acoustic Neuroma
Not every acoustic neuroma requires treatment. If your tumor is very small and not causing any symptoms, your doctor may recommend monitoring your condition until any changes occur. However, if your tumor is causing (or may cause) issues, your doctor will likely recommend treatment.
Surgery for Acoustic Neuroma
Some patients may require surgery to remove all or part of an acoustic neuroma. This could be the case if an acoustic neuroma is very large or if a patient is young. Most patients will spend up to a week in the hospital following surgery and 6-8 weeks recovering at home. However, not all patients are good surgical candidates, and sometimes the risk of acoustic neuroma surgery outweighs the benefits.
Gamma Knife Radiosurgery for Acoustic Neuroma
Gamma Knife radiosurgery isn’t actually a surgery at all. Rather, it’s an advanced form of radiation therapy that can treat an acoustic neuroma without any incisions or hospital stay. This makes it a great option for people who cannot undergo surgery, whose acoustic neuroma is hard to reach or who simply prefer a minimally invasive treatment option. Gamma Knife radiosurgery can also be used as an adjunct therapy following surgery to eliminate any remaining tumor cells. There’s no hospital stay after Gamma Knife radiosurgery. In fact, most people are back to work and normal activities within a day or two.
Continue the Discussion
Now that you understand a little more about acoustic neuroma, including using an MRI during the diagnosis process, it’s important to continue the discussion with your personal doctor. He or she will have the most intimate knowledge of your specific situation. Consider the information you’ve learned and be sure to ask any new or lingering questions you may have. It’s important you are comfortable as you move through the diagnosis and treatment process and, ultimately, recovery.