Acoustic neuromas

An acoustic neuroma is a benign (non-cancerous) tumour of the nerve that connects the inner ear to the brain. Acoustic neuromas usually grow slowly and do not spread to other parts of the brain. The most common symptoms are:

  • loss of hearing in the affected ear
  • a buzzing or ringing noise (tinnitus)
  • feeling dizzy
  • problems with balance.

You will have some hearing tests and a brain MRI (magnetic resonance imaging) scan to diagnose the tumour. Your treatment will depend on the size of the tumour and how symptoms affect you. If they are mild, you may not need treatment immediately, but you will have regular scans to monitor the tumour.

People are often treated with a type of radiotherapy called stereotactic radiotherapy. Surgery is used for bigger tumours. Surgery may cause hearing loss and other side effects. Your doctors will discuss these with you and will explain how to cope with them.

Understanding acoustic neuromas

This information is about acoustic neuroma and its symptoms, diagnosis and treatments. It should be read with our general information about brain tumours, which has more detailed information on tests, treatments and side effects.

An acoustic neuroma is a benign (non-cancerous) tumour that usually grows slowly. A benign tumour can cause problems as it grows by pressing on surrounding tissue. But, unlike a malignant (cancer) tumour, it can’t spread from where it started to other parts of the brain.

Acoustic neuroma develops from the lining of the main nerve that connects the inner ear to your brain. This is called the acoustic or hearing nerve. It controls your hearing and balance. The facial nerve runs next to it. Although acoustic neuromas are a type of brain tumour, they do not spread into (invade) the brain. But if a tumour grows large enough, it can interfere with nearby nerves or important functions of the brain.

Acoustic neuromas start in Schwann cells, which cover the hearing nerve, so they are sometimes called a vestibular schwannoma. They are most likely to be found in people aged in their 40s to 60s.


Causes of acoustic neuromas

The cause of acoustic neuromas is unknown. In a small number of people, acoustic neuroma is linked to an inherited (genetic) condition called neurofibromatosis type 2 (NF2). In this situation, acoustic neuromas usually develop on the hearing nerves on both sides of the head (bilateral tumours).

Having hadradiation for head and neck conditions as a child may increase the risk of developing acoustic neuroma.


Symptoms of acoustic neuromas

Acoustic neuromas are usually slow-growing tumours and symptoms often develop gradually over several years. The most common symptoms are:

  • loss of hearing in the affected ear
  • a buzzing or ringing noise (tinnitus)
  • feeling dizzy
  • problems with balance.

If the tumour presses on nearby nerves affecting the face, it can cause numbness, tingling or weakness on one side of the face. Rarely, larger tumours may lead to increased pressure on the brain, causing headaches and changes to your eyesight.


Tests for acoustic neuromas

Your doctors need to find out as much as possible about the type, position and size of the tumour so they can plan your treatment. You may have a number of different tests.

You will have tests to check your hearing (audiometry) and sometimes to check your sense of balance. The doctor will examine you thoroughly and also test your reflexes and the power and feeling in your arms and legs.

MRI scan

This scan uses magnetism to build up a detailed picture of areas of your body. You may be given an injection of dye, into a vein, to improve the images from the scan. We have more detailed information about having an MRI scan.

CT scan

A CT (computerised tomography) scan uses x-rays to build a three-dimensional picture of the inside of the body. You may be given either a drink or injection of dye. This is to make certain areas of the body show up more clearly. We have more detailed information about having a CT scan.


Treatment for acoustic neuromas

The treatment you have will depend on the size of the tumour, how the symptoms are affecting you and your general health. The main treatments are radiotherapy or surgery.

A team of specialists will plan your treatment. This will usually include:

  • a neurosurgeon – a doctor who specialises in operating on the brain or nervous system
  • a neuro-otologist – an ear, nose and throat (ENT) doctor who specialises in treating illnesses affecting the skull base and nearby nerves
  • a clinical oncologist – a doctor who specialises in treating cancer with radiotherapy and chemotherapy
  • a specialist nurse – who gives information and support to people with brain tumours.

Your specialist will explain the aims of your treatment. They will tell you about the benefits and disadvantages and possible risks. You will have time to talk this through with them before you make any treatment decisions. You may be given a choice of treatment options. Let your specialist know if you need more information or time.

Monitoring (watch and wait)

If the tumour is small and causing only mild symptoms, you may decide not to have treatment at first. Instead, you will see your specialist regularly and have tests to check the tumour (monitoring). This can help your doctor know if and when to recommend treatment.

Treatment can cause side effects and some of these may be permanent. Acoustic neuromas are often slow-growing and it may be a long time before your symptoms change.

Stereotactic radiotherapy and radiosurgery

Radiotherapy treatment uses high-energy rays to destroy the tumour cells. You may have this treatment to shrink an acoustic neuroma and stop it growing.

Acoustic neuromas are usually treated with a specialised type of radiotherapy called stereotactic radiotherapy. Several beams of radiation are given from different angles, overlapping at the tumour. This gives a high dose to the tumour and very low doses to surrounding healthy tissue, which helps reduce side effects.

You may have this treatment over 3–10 sessions spread over two weeks. Sometimes treatment is given as daily sessions from Monday to Friday for 5–6 weeks.

Stereotactic radiotherapy can also be given in one session of high-dose treatment. This is called stereotactic radiosurgery (or sometimes gamma knife treatment). This treatment is often used to treat smaller tumours. Despite the name, stereotactic radiosurgery doesn’t involve any surgery.

Radiotherapy for acoustic neuroma has a lower risk of permanent side effects, such as hearing loss and nerve damage, than surgery. But some people may still have some hearing loss and occasionally some damage to the nerves that affect the face.

Rarely, some people will need further treatment in the future because the acoustic neuroma starts growing again.

Surgery

Surgery is likely to have more side effects than stereotactic radiotherapy or radiosurgery. So it’s usually only used to remove larger tumours.

Your surgeon will explain what it involves and the possible complications and risks. The operation is done through the skull. Sometimes the surgeon leaves a tiny part of the tumour to try to avoid damaging the facial nerve. This can be treated with stereotactic radiosurgery if needed.

Surgery will usually cause hearing loss in the affected ear. Your surgeon may talk to you about being fitted with a special type of hearing aid, which diverts sounds from the affected ear to your other ear. You will usually see a hearing specialist for expert help and advice.

Doctors may delay surgery, if possible, in people who have large tumours of both acoustic nerves, because of the risk of total hearing loss. You will have MRI scans to monitor the tumours. Occasionally, they operate on one side first. If you can hear with this ear after surgery, they will then operate on the other side. If hearing is lost during the first operation, it may be possible to delay surgery on the second tumour, or to use radiotherapy.

Sometimes, surgery damages the facial nerve. This can cause drooping (palsy) of one side of the face, which is sometimes permanent. It can affect actions like chewing and blinking. A physiotherapist will show you exercises and massage that you can do to help improve this. Some people also get a dry eye. Eye drops will help with this. If necessary, your doctor can refer you to an eye specialist. The British Acoustic Neuroma Association has more information.


Driving

You may not be allowed to drive for a period of time. Although this can be upsetting, it’s important to follow the advice you are given.

You will need to contact the Drivers and Vehicle Licensing Association (DVLA) if you live in England, Scotland or Wales. If you live in Northern Ireland you will need to contact the Driver and Vehicle Agency (DVA). They will advise you of any restrictions on your right to drive:

  • The Drivers and Vehicle Licensing Agency (DVLA) has information about driving with a medical condition if you live in England, Scotland or Wales. Visit GOV.UK or call 0300 790 6806.
  • The Driver and Vehicle Agency (DVA) has information about driving with a medical condition if you live in Northern Ireland. Visit nidirect or call 0845 4024 000.

If you’re not sure what you should do, check with your cancer doctor or specialist nurse. They will explain things to you.


Follow-up for acoustic neuromas

After your treatment has finished, you’ll have regular check-ups, tests and scans. These appointments are a good opportunity to discuss with your doctor about any worries or problems you have.

Many people find they get very anxious before appointments. This is natural. It may help to get support from family, friends or the specialist organisations listed below.

British Acoustic Neuroma Association

The British Acoustic Neuroma Association gives information and support for people with acoustic neuroma. It has a network of local branches throughout the UK.

The Neuro Foundation

The Neuro Foundation offers information and advice about neurofibromatosis.