Disorders of auditory nerve

What is vestibular schwannoma?

a benign tumor (Schwann cells) in the internal auditory pathway (brain) that can compress the auditory nerve (8) and affect parts of the brain

VS is the most common tumor of the skull base

yes, it accounts for 8-10% of all cranial tumors and affects those typically 30 - 60

is VS hereditary?

no but it can be linked to a genetic mutation

most common VS symptoms

unilateral hearing loss and unilateral tinnitus and headaches

least common VS symptoms

imbalance and facial numbness/weakness

why is early diagnosis important for VS?

earlier diagnosis and monitoring is essential to avoid life threatening symptoms but typically people only notice it when something isn’t right so this ideal diagnosis time is not always an option and common symptoms are also common with middle and inner ear disorders

how do audiological tests fair for VS?

word rec poor

acoustic reflexes elevated or absent

retro screen ABR

Treatment types for VS

Observation

Surgery

Radiation

what is the kicker with observation treatment?

good when tumor is small and slow growing but needs to happen frequently and tumor can grow fast

what is the kicker with surgical treatment?

it’s such a small place and it’s hard to preserve the integrity of the hearing mechanism. Paitents are expected to go deaf.

what is the kicker with radiation therapy?

can reduce or limit size but is typically good for small tumors and older or poor health patients

ANSD hearing thresholds

can vary from mild to profound

hearing thresholds typically worse than would be expected

ANSD test results

present OAEs

absent or abnormal ABRs

near normal cochlear function

ANSD diagnosis

normal OHC function in present of abnormal ABR

medical imaging to rule out cochlear nerve deficiency

ANSD treatment

some may benefit from hearing aids or CI but it’s really dependent on each person. Consider ASL