Case 5. Acute vertigo and unsteadiness
What is the lesion?
There are many causes of acute vestibulopathy (box).
Vestibular neuritis
Labyrinthitis
Toxic
Labyrinthine artery infarction (branch of AICA)
Meniere’s disease
Vestibular migraine
Cogan syndrome (rare, autoimmune disorder against inner ear epithelium)
The strict lateralisation in this case is helpful and implies a structural cause. There is also no hearing loss – which goes against many more serious pathologies. There are no toxic exposures suggested either.
The most likely cause is vestibular neuritis - acute inflammation in the nerve.
This is a clinical diagnosis without any specific investigation available. It’s not visible on imaging for example.
It may reflect a viral cause, similar to Bell’s palsy in nerve VII, and like Bell’s palsy, it comes on acutely, peaks, then gradually resolves in the following weeks.
Vestibular neuritis is common and is the major cause of acute peripheral vertigo, but it is important to make a solid clinical diagnosis. The diagnostic criteria are strict and do not allow central or audiological abnormalities. They also require the presence of peripheral-pattern HINTS findings.
All of the following must be present:
A. Acute/subacute sustained vertigo (rotatory or non-rotatory); moderate-severe, lasting > 24 hours
B. Spontaneous peripheral-type nystagmus (horizontal-torsional, direction unchanging, enhanced by fixation suppression)
C. Reduced VOR on the side opposite to the fast phase of nystagmus
D. No central neurological, audiological (hearing/tinnitus) or otologic (e.g. ear pain) symptoms
E. No central neurological signs (including skew deviation) or audiological signs
F. Not otherwise explained by an alternative cause