Gaze-evoked horizontal (“sidebeat”) nystagmus, which has its fast phase in the direction of gaze (“direction changing”), as opposed to peripheral vestibular nystagmus, which has its fast phase always directed opposite to the side of the lesion (“unidirectional”)
Increase in nystagmus amplitude when fixation is eliminated by occluding one eye is occluded and the other examined with a direct ophthalmoscope (“fixation suppression”) (See
Eye Movement Examination
)
Tinnitus, hearing loss
Absence of ataxia or diplopia
If you are unable to make a firm diagnosis, order brain MRI/MRA and consider ordering formal electronystagmography
For any type of acute peripheral vestibulopathy, prescribe oral antihistamines and anti-emetics to reduce acute vertigo and nausea
For suspected acute vestibular neuritis/neuronitis, prescribe a 10-day course of prednisone 1m/kg (there is evidence for reactivation of herpes simplex virus type 1; a large trial of showed shortening of disease course with steroid but no benefit of anti-viral therapy)
For BPPV, prescribe otoconial repositioning maneuvers
Clinical manifestations of viral/post-viral labyrinthitis/vestibular neuritis/vestibular neuronitis usually resolve almost completely within days/weeks with low chance of recurrence (but rigorous testing often shows chronic residual dysfunction)
Clinical manifestations of other acute peripheral vestibulopathies have variable duration, depending on the cause
Otoconial repositioning maneuvers often cure BPPV; various options are effective in Ménière disease; anti-migrainous remedies are variably effective in preventing vestibulopathy of migraine; autoimmune causes may be effectively treated with disease-modifying agents
Clinical manifestations of central lesions may recover slowly, but often worsen, endure, and become permanent, depending on the cause
