Acoustic neuroma

Most common intracranial schwannoma.

80% of all cp angle tumours.

it's benign. B/l acoustic neuroma is diagnostic of NF2. 

Most common age group is 40 to 60 yrs of age. 

Tumour is radioresistant.90 % of cases are u/l. 

Most schwannomas are sporadic.

Earliest symptom: Deafness, tinnitus .retrocochlear hearing loss, true vertigo not seen due to central adaptation. Marked difficulty in speech understanding.earliest nerve involved is 5th cranial nerve.2nd nerve is facial.

Earliest sign: corneal reflex is impaired.

Histelberger sign and teal's sign +ve .

recruitment is negative.

BERA: delay in 5th wave.

MRI is gold standard investigation.

Vertebral angiography is done for differentiation from other CP tumours.

Surgery is TOC.

For hearing rehabilitation in b/l acoustic neuroma: Auditory brain stem implant.