Acoustic Neuromas Flashcards
what is the other name of acoustic neuroma?
Vestibular Schwannoma
what is an acoustic neuroma?
Tumour arising from the Schwann cells of the myelin sheath
what part of the VIII nerve is often affected in acoustic neuroma?
superior vestibular portion
what is the growth pattern of acoustic neuromas?
- May develop inside auditory canal, or outside it
- Intracranial – expand into cerebellopontine angle
- Extracranial – infringe nerves, displace bone tissue
what is the histology of acoustic neuromas?
veroky bodies (long streaky cells)
what are the causes of acoustic neuromas?
95% sporadic
NF1
NF2
what are the clinical features of acoustic neuromas?
VIII: vertigo, unilateral sensorineural hearing loss, unilateral tinnitus
V: absent corneal reflex
VII: facial palsy
Large tumours – ipsilateral cerebellar signs, increased ICP signs
Sporadic – unilateral
NF – bilateral
Others: nystagmus? Bloody discharge from ear
how are acoustic neuromas diagnosed?
MRI, audiometry
what is the management of acoustic neuromas?
Surgery, stereotactic radiotherapy or observation
what are the clinical features of NF 1?
Café au lait spots Axillary/groin freckles Peripheral neurofibromas Iris hematomas Scoliosis Pheochromocytomas
what is the syndrome associated with NF 1?
Von Recklinghausens syndrome
what is the genetic mutation associated with NF1?
chromosome 17
what are the clinical features associated with NF2?
o Bilateral acoustic neuromas
o Multiple intracranial schwannomas, meningiomas, and ependymomas