Accoustic neuroma

Question 1

What are the clinical features of accoustic neuroma?

Answer 1

• Typically unilateral SNHL: may be gradual or sudden (uncommon, haemorrhage into a cyst)
• Tinnitus
• Possible vestibular disturbance (not as common as tumour is slow growing and the brain can compensate): giddiness/imbalance but NOT RLY vertigo
• Larger tumours may cause intracranial symptoms -> e.g. headache, confusion, neurologic symptoms

Question 2

What are the signs of acoustic neuroma?

Answer 2

• Signs of ↑ ICP
• CN palsies (CN5 dysfunction more common than CN7)
• CN5: paresthesia (numbness), hypoesthesia (decreased sensation), and/or unilateral facial pain
• Brun’s nystagmus (characteristic of large CPA tumours (> 3.5 cm acc to EyeWiki))

Question 3

What are the investigations for acoustic neuroma?

Answer 3

• PTA: unilateral SNHL
• Vestibular tests 🡪 may have reduced or absent caloric responses
• **MRI IAM (gold std): CPA angle tumour

Question 4

What is the management of acoustic neuroma?

Answer 4

In small and slow growing tumours, consider watchful waiting w serial MRI scans (4-6 months)

Definitive:

• Stereotactic (highly-focused) RT for small tumours or poor surgical candidates (called gamma knife)
• Sx excision

If hearing improves on PTA in Dx’ed acoustic neuroma -> MRI IAM TRO r/o ruptures