An Introduction to Acoustic Neuroma (Vestibular Schwannoma)

Article contributed by a medical advisory panel member of the British Acoustic Neuroma Association (BANA)

For some people, sudden sensorineural hearing loss (SSNHL) may be caused by an acoustic neuroma (also known as vestibular schwannoma).

What is an Acoustic Neuroma?

An acoustic neuroma is a non-cancerous (benign) tumour that grows on the hearing and balance nerve. This nerve is located in a small channel in the skull that runs from the inner ear to the brain.

Acoustic Neuroma and Hearing Loss

Eighty-five per cent of patients with acoustic neuroma have hearing loss in the ear containing the tumour when they first present. This hearing loss is most commonly in the high frequencies.

The degree of hearing loss is often variable and it is common for the hearing to deteriorate gradually over time. For patients who still have functioning hearing when they first present, around half will lose their hearing over the first 5 years following diagnosis. Hearing may also become distorted.

Although most people affected have gradual hearing loss, around 10% of patients with acoustic neuroma experience a sudden hearing loss.

Acoustic Neuroma and Sudden Hearing Loss

There are several reasons why someone with an acoustic neuroma might develop hearing loss, including sudden hearing loss.

The tumour may put pressure on the hearing nerve, causing hearing problems, ringing in your ears (tinnitus), and unsteadiness. This pressure can also affect the blood supply to the the part of the inner ear involved in hearing, known as the cochlea.

Very occasionally, the tumour can grow into the cochlea, causing damage resulting in hearing loss.

Sometimes people with an acoustic neuroma may develop Meniere’s Disease, which can also cause hearing loss.

Sudden hearing losses are most likely to result from sudden blockage of the blood supply to the inner ear.

Treatment for Sudden Hearing Loss Due to Acoustic Neuroma

Sudden hearing losses due to acoustic neuroma can be treated with steroids. Treatment needs to take place as soon as possible after its onset to increase the chances of success.

Ideally, steroid treatment should be started within 2 weeks of onset of the sudden hearing loss, although some doctors treat people up to 6 weeks after onset.

There are two main ways to give the steroids. They can be given by mouth (orally) or via an injection into the ear (also known as intratympanic steroids).

Oral Steroids vs Steroid Injections

There are several types of oral steroids, the most common being Prednisolone. These are usually given over a 5 days.

Studies suggest that the amount of steroids reaching the inner ear is much higher if it is given as an injection. The steroid is injected into the space behind the eardrum (called the middle ear). It then gets absorbed by the membranes separating the middle ear from the inner ear. This process takes half an hour or so.

The steroid injections are given in different ways by different doctors but most offer 2 or 3 injections over a few days.

Studies suggest that steroids should be used, but it is unclear if oral steroids are more effective than steroid injections. Some doctors treat with both. Others use oral steroids and if that fails, treat with injections. Others just treat with injections.

More Information

The British Acoustic Neuroma Association supports people and their networks who have had a diagnosis of acoustic neuroma and the symptoms associated with it. We offer in-person and virtual support groups around the UK.

We have a Listening Ear Service where other’s affected by acoustic neuroma are happy to provide peer-to-peer support. Lots of leaflets on the varying symptoms are available on our website.

Our Headline magazine is available three times a year; along with online forums and a closed Facebook page; with access to a medical advisory panel of experts who give their time freely.

Acknowledgements:

Thank you to Julie Dixon, Chief Executive of British Acoustic Neuroma Association (BANA), and the medical advisory panel member for this contribution.