Vestibular schwannoma Flashcards
What is a vestibular schwannoma (AKA acoustic neuroma)?
A benign tumour of the Schwann cells surrounding the auditory nerve (vestibulocochlear nerve) that innervates the inner ear.
Which cranial nerve is the vestibulocochlear nerve?
CN VIII
Which portion of the vestibulocochlear nerve does a vestibular schwannoma predominantly affect?
Vestibular portion - hearing loss, tinnitus & balance issues.
What cells does a VS arise from?
Schwann cells
Acoustic neuromas are usually unilateral.
What condition are bilateral vestibular schwannomas seen in?
Neurofibromatosis type 2
Where are Schwann cells found?
PNS
What is role of Schwann cells?
Provide myelin sheath around neurones
Where in the brain do VS occur?
At the cerebellopontine angle (sometimes referred to as cerebellopontine angle tumours).
Typical age of presentation of VS?
40-60 y/o
What clinical features are seen in VS?
1) Unilateral sensorineural hearing loss (often the first symptom)
2) Unilateral tinnitus
3) Dizziness or imbalance
4) A sensation of fullness in the ear
5) Facial nerve palsy (if the tumour grows large enough to compress the facial nerve)
6) Headache, N&V (increased intracranial pressure in large tumours)
What is the most common presenting symptom of VS?
Unilateral sensorineural hearing loss
Who should patients with a suspected vestibular schwannoma be referred urgently to?
ENT
Investigations in VS?
1) Audiometry
2) Brain imaging: MRI
Role of audiometry in VS?
Used to assess hearing loss. There will be a sensorineural pattern of hearing loss.
What is the gold standard imaging for diagnosing VS?
MRI
