Vestibular neuronitis

Question 1

What causes vesibular neuronitis?

Answer 1

• Inflammation of vestibular portion of CN8 🡪 vertigo (hearing unaffected)
• Aetiology unknown; may be viral
• May be preceded or occur currently w/ a viral illness
• Resolution occurs gradually over wks, w/ slow compensation

Question 2

What are the symptoms of vesibular neuronitis?

Answer 2

• Sudden onset vertigo lasting for 1 day or more
• Important negatives -> no hearing loss, no tinnitus, no aural fullness, no neurological impairment
• (if SNHL also present, then = labyrinthitis)

Question 3

What are the signs of vestibular neuronitis?

Answer 3

• Nystagmus 🡪 horizontal w/ torsional, suppressed by visual fixation, fast phase away from side of lesion
• Normal ear examination, neurological examination (including hearing test)

Question 4

What are the investigations required for vestibular neuronitis?

Answer 4

• Audiogram (PTA) 🡪 no hearing loss
• +/- VNG (videonystagmography) 🡪 reduction in caloric response
• +/- MRI brain 🡪 r/o brainstem or cerebellar infarction/haemorrhage

Question 5

How is vestibular neuronitis managed?

Answer 5

• Supportive care: vestibular suppressants (e.g. Prochlorperazine, Cinnarizine. Reserved only for acute conditions because they can have extramedullary effects, e.g. Parkinsonism) and vestibular rehab (key)
• Steroids (for anti-inflammatory action) and consider acyclovir