What's an acoustic neuroma and how is it treated?

Acoustic-neuroma_large 

An acoustic neuroma is a rare, benign tumor that forms between the ear and the brain. These tumors are also called a vestibular schwannoma. At The Ohio State Wexner Medical Center, we annually treat between 150 and 200 patients, ranging from teenagers to 90-year-olds.

What are the symptoms of an acoustic neuroma?

The classic symptom for an acoustic neuroma is hearing loss that’s worse in one ear than the other. Common hearing loss, which is caused by conditions such as noise exposure, for example, typically occurs over time and is about the same in each ear. I you experience worse hearing loss on one side—especially sudden onset—you need to seek medical attention. Other symptoms can include dizziness and balance problems. None of these symptoms should be ignored. 

How is acoustic neuroma treated?

You’ll be referred for an MRI to check for the presence of a tumor. If the tumor is small, your medical professional will go over all management options, including surgery, radiation or waiting and watching via repeated MRI scans. Small tumors that aren’t causing secondary symptoms like balance issues don’t necessarily require surgery. You’ll receive a second MRI in about six months and, if there’s no change, annual follow-up MRIs.

If the tumor is large, which sometimes occurs if left untreated, or if the follow-up MRIs reveal that the tumor is growing, there are several treatment options. Determining the best treatment is dependent on the individual patient. There is no medication that can reduce the size of the tumor in part because it’s non-cancerous, so chemotherapies are typically ineffective. 

A non-surgical treatment option that may be effective in stabilizing the tumor’s size is radiation therapy that delivers a precisely-targeted dose of radiation without damaging the tissue around it. This procedure is mostly offered for tumors that are growing, so if the follow-up MRI shows no increase in size, radiosurgery won’t be recommended. 

If the tumor is large or growing, we’ll likely discuss surgery as an option. You might consider this option sooner because you prefer removal rather than waiting, but other patients don’t want surgery. When you come to me with questions—and I sometimes advise patients seeking a second or third opinion—I’ll present all the options, including potential side effects. If the tumor is large and causing issues with brain health, removal may be the best choice. But when the tumor is small, the decision-making process is commonly more complicated.

Can my hearing be saved?

In some cases, we can preserve your hearing, but often the tumor has already caused a substantial hearing decline. Our ability to surgically preserve hearing depends on the precise location of the tumor, and our ability to access it for removal. There are three possible routes of entry: above the ear, behind the ear or through the ear bone. The process is highly individualized. We consider your overall health, age, hearing, balance issues and what you want. There’re advantages with each approach, and we’ll tailor the procedure for you with lots of testing. In some cases, we might recommend placement of a cochlear implant during the surgery to provide hearing recovery. 

I work closely with neurosurgery in these cases. The surgery for a large tumor can take from half a day to a full day in the operating room. A team approach is better for us as doctors and, most importantly, it’s better for our patients.

Oliver Adunka is an otolaryngologist and neurotologist specializing in hearing and brain disorders at The Ohio State University Wexner Medical Center, and a professor in The Ohio State University College of Medicine.