Acoustic Neuroma Flashcards
What is the definition of acoustic neuroma?
Rare, benign tumour of CN VIII sheath that arises in internal auditory meatus.
What are some risk factors for acoustic neuroma?
May be associated with extensive exposure to loud noise
Neurofibromatosis type 2 (if bilateral and young)
(however 95% are sporadic and unilateral)
What is the pathophysiology of acoustic neuroma?
Associated with vestibular portion of CN VIII and occurs within temporal bone
Represent 80-90% of cerebellopontine angle tumours
What is the gross appearance of acoustic neuroma?
Circumscribed tan/white/yellow mass
What is the histological appearance of acoustic neuroma?
Encapsulated
Two growth patterns (Antoni A and Antoni B)
What are some clinical features of acoustic neuroma?
Progressive sensorineural unilateral hearing loss and tinnitus
Imbalance in larger tumours
Facial numbness due to compression of trigeminal nerve as tumour enlarges
What are some investigations for acoustic neuroma?
MRI
What is the management of acoustic neuroma?
Surgical excision (definitive)
Monitoring with MRI at 6 month interval for small lesions that are not growing