Clinical criteria of positional vertical nystagmus in vestibular migraine.

OBJECTIVES: The goal of this study was to identify key diagnostic criteria for positional vertical nystagmus caused by vestibular migraine (VM).

MATERIALS AND METHODS: The study group included a case series of 13 subjects with VM (10 females and three males with age 38.6 ± 8.9 years); they were complaining of positional vertigo. They were subjected to thorough audiovestibular examination and treated with cinnarizine or topiramate Results: The entire study group demonstrated positional vertical nystagmus (eight patients had up-beating nystagmus and five patients had down-beating nystagmus). The vertigo and nystagmus were elicited in one or more of the following positions: the right & left Dix-Hallpike, supine with head center, head right, and head left positions. The nystagmus had no latency period. It was persistent, non-fatigable and markedly reduced by visual fixation. Prophylactic therapy of VM (topiramate or cinnarizine) cured the positional vertigo in 92% of the study group. Neither the positional vertigo nor the nystagmus recurred in a 3-6 months follow-up period.

CONCLUSIONS: VM can induce characteristic form of vertical positional nystagmus and vertigo, which would be treated by medications used for controlling the VM.