Acoustic Neuroma Flashcards
What are acoustic neuromas?
benign tumours of the Schwann cells surrounding the auditory nerve (vestibulocochlear nerve) that innervates the inner ear
What are acoustic neuromas also called?
Vestibular schwannomas, as they originate from the Schwann cells
Schwann cells are found in the peripheral nervous system and provide the myelin sheath around the neurones
Where are acoustic neuromas located?
at the cerebellopontine angle
are sometimes referred to as cerebellopontine angle tumours
Are acoustic neuromas usually unilateral or bilateral?
Usually unilateral
Bilateral acoustic neuromas are associated with?
Neurofibromatosis type II
TOM TIP: Bilateral acoustic neuromas almost certainly indicate neurofibromatosis type II. This is a popular association in exams, so worth remembering.
Typical presentation of acoustic neuromas?
The typical patient is aged 40-60 years presenting with a gradual onset of:
Unilateral sensorineural hearing loss (often the first symptom)
Unilateral tinnitus
Dizziness or imbalance
A sensation of fullness in the ear
They can also be associated with a facial nerve palsy if the tumour grows large enough to compress the facial nerve.
Investigations for auditory neuromas?
Audiometry is used to assess hearing loss. There will be a sensorineural pattern of hearing loss.
Brain imaging (MRI or CT) is used to establish the diagnosis and features of the tumour. MRI provides more detail than CT.
Management of auditory neuromas?
ENT specialist management options include:
- Conservative management with monitoring may be used if there are no symptoms or treatment is inappropriate
- Surgery to remove the tumour (partial or total removal)
- Radiotherapy to reduce the growth
Notable risks associated with treatment are?
Vestibulocochlear nerve injury, with permanent hearing loss or dizziness
Facial nerve injury, with facial weakness
