Can a hearing test reveal a brain tumour?

A form of benign brain tumour known as a vestibular schwannoma grows on the hearing and balance nerve, and the first sign of its presence can be loss of hearing on one side. Audiologists know about this and if they are concerned that the audiology test suggests an atypical hearing loss requiring further investigation, they will suggest a referral to a neurosurgeon, such as Mr Patrick Grover who specialises in these types of skull based tumours. 

Hearing loss or tinnitus on one side

Vestibular schwannomas or acoustic neuromas most commonly present with hearing loss or tinnitus on one side. The tumour can also be the cause of balance problems. In his article, Treating skull based tumours, Mr Grover explains, "As they grow larger these tumours can press on the nerve that gives sensation to the face resulting in facial numbness, or shooting pains in some circumstances. If you do have hearing loss on one side, the first port of call is an audiologist who will be able to tell if this is the kind of problem that can be associated with such tumours (and requiring an MRI scan), or is due to another reason such as impacted ear wax for example.

Mr Grover goes onto explain that, "An MRI of the area known as the internal auditory meati (IAMs) is the diagnostic scan of choice if the audiology test suggests an atypical hearing loss requiring further investigation.

The comedian Vic Reeves has recently talked about how he is now completely deaf in one ear as the result of an inoperable vestibular schwannoma. Mr Grover explains, "The main difficulty with treating vestibular schwannoma is the proximity of the nerve to the face on that side. This ‘facial nerve’ is immediately adjacent to the hearing and balance nerve, and as such becomes progressively stretched by tumour growth". However, for most people these tumours are treatable, and various treatment options are available including Gamma Knife.

Gamma knife treatment for vestibular schwannomas

The majority of tumours, particularly those of a smaller size, are suitable for treatment with stereotactic radiosurgery techniques such as Gamma Knife radiosurgery. This has the benefit of being non-invasive, and has a lower risk of injury to the facial nerve (in the region of 1% of cases or less). It does not remove the tumour, but it prevents further growth in approximately 95% of tumours or more depending on the size. There are risks of exacerbating balance problems for example for a period of time, or accelerating hearing loss, but compared with ongoing tumour growth these side effects are usually well tolerated. Treatment is carried out as a day case, and normal activities including work can continue within a few days.

Mr Patrick Grover is lead for cranial neurosurgery at the National Hospital for Neurology and Neurosurgery and Postgraduate Medical Education (PGME) education lead.

His areas of expertise include:

• Meningioma
• Vestibular Schwannoma
• Cavernoma
• Aneurysm
• Arteriovenous malformations (AVMs), and
• Gamma Knife Radiosurgery