Although vestibular neuritis (VN) usually includes a single attack of prolonged vertigo (lasting more than 1 day), we have previously observed several patients with VN who experienced paroxysmal dizziness prior to onset of the continuous dizziness typical for VN. Since vertebrobasilar territory strokes may also be heralded by recurrent isolated dizziness (usually vertigo), there exists the possibility of diagnostic confusion between VN and stroke-related vertigo. We thus sought to characterise the features of transient dizziness prior to the prolonged vertigo attack of VN.

Methods

From March 2006 to August 2007, 255 consecutive patients with VN were recruited at four dizziness clinics of University Hospital in Korea. All patients met the clinical diagnostic criteria for VN including sudden onset of prolonged vertigo (more than 1 day) with unidirectional, spontaneous, horizontal nystagmus with a torsional component, absence of other auditory or neurological findings, reduced or absent caloric response and no previous history of neuro-otological diseases.1 Asymmetry of vestibular function was calculated using the Jongkees formula, and caloric paresis was defined by a response difference of 25% or more between the ears. Patients with an onset of transient dizziness within 7 days before VN attack were considered to have prodromal dizziness. On admission, all patients were carefully interviewed by authors …