Acoustic neuroma

An acoustic neuroma grows on the nerve that handles hearing and balance. The most common symptoms include: 

• hearing loss that gets worse over time (90% of patients experience unilateral hearing loss as a first symptom)

• tinnitus 

• ear fullness

• unsteadiness and loss of balance 

• dizziness/vertigo

• facial numbness, weakness, tingling or pain

Less common symptoms include:

• frequent headaches

• earache

• visual problems 

• fatigue and lack of energy

The cause of an acoustic neuroma is unknown, and the condition is rare and generally affects only a small proportion of the population. As with other brain tumours, there are several risk factors - such as age, family history and any head injuries - which can increase the possibility of a tumour developing.

Around 7% of cases are caused by a rare genetic disorder known as neurofibromatosis type 2 (NF2). This condition typically causes acoustic neuromas that affect both ears at the same time.

Diagnosing an acoustic neuroma can be difficult, as many symptoms mimic a range of other conditions. Similarly, as the first indication is generally hearing loss, an acoustic neuroma is often misdiagnosed and minimised to this particular symptom. 

Acoustic neuromas are generally diagnosed with:

• A physical examination: a doctor will examine both the patient’s body and inner ear to check for any other underlying issues.

• A hearing test (audiogram): generally the first specific test used to diagnose an acoustic neuroma, an audiogram determines how well patients can hear sounds and speech.

• Balance testing (electronystagmography or ENG): an ENG records electrical activity and is used to measure the brain, eyes and inner ear's response to balance and positioning.

• Imaging (typically an MRI or CT scan): used to determine the size and placement of the tumour, and the best course of action.

There are three treatment options for patients with an acoustic neuroma. These depend on factors such as the size of the tumour, whether or not it’s growing, any underlying medical conditions, the patient's age and the severity of symptoms.
Treatment options include: 

• Monitoring the tumour: acoustic neuromas aren’t generally life-threatening; if the tumour doesn’t appear to be growing, immediate and invasive treatment isn’t always necessary. In these cases, doctors will typically monitor the tumour with regular MRI scans and will treat any symptoms as they occur.

• ​​Brain surgery: a neurosurgeon or EMT surgeon will operate if the tumour is large or if it’s continuing to grow and causing a range of other symptoms. Depending on the size of the tumour, either all or part of it will be removed. While surgery can’t reverse hearing loss, removing the tumour aims to maintain nerve function in the face and preserve existing hearing.

• Stereotactic radiosurgery: a non-invasive procedure directly targeting the tumour without damaging the surrounding tissue. Stereotactic surgery aims to slow the growth of the tumour, rather than to remove it.