Causes of acoustic neuromas
Most acoustic neuromas occur sporadically with no known cause or family history. A small percentage of acoustic neuromas (5%) are inherited and associated with neurofibromatosis type 2 (NF2), a genetic disorder. Individuals with NF2 often develop tumors on both sides of the vestibulocochlear (hearing and balance) nerve at a younger age. They also typically develop other types of benign tumors in the brain and spine.
Importantly, there’s no evidence to suggest environmental concerns, such as cellphone use, noise exposure or dietary factors, are linked to the development or growth rate of acoustic neuromas.
Acoustic neuroma symptoms
Although acoustic neuromas form on the balance nerve, they most commonly affect your hearing abilities — not your balance. Symptoms include:
- One-sided or asymmetric (uneven) hearing loss
- Feeling of fullness in the ear
- Tinnitus (ringing in the ear)
- Vertigo
- Balance problems
- Facial numbness or twitching (if the tumor is very large)
With acoustic neuroma, the degree of hearing loss is not always associated with the size of the tumor. Many patients experience few hearing loss symptoms even with a large tumor, while some might not display any symptoms. Some patients lose hearing even when the tumor is very small.
How is an acoustic neuroma diagnosed?
Because symptoms usually develop slowly over time and are often ignored, it can be difficult to diagnose acoustic neuromas (vestibular schwannomas). In patients with significant asymmetric hearing loss, a magnetic resonance imaging (MRI) scan to look for an acoustic neuroma is sometimes advised.
Imaging scans are also recommended for people who experience a sudden drop in their ability to hear; however, the likelihood of having an acoustic neuroma in this case is only about 1%.
Hearing tests might also be recommended. If you have sudden hearing loss or are experiencing asymmetric hearing loss, you should contact the audiology department at the Ohio State Wexner Medical Center to start the process of diagnosing the cause of your hearing issues.