Eye Movement Abnormalities During Different Periods in Patients with Vestibular Migraine.

In patients with VM, abnormal oculomotor signs can be found during both vertigo attacks and asymptomatic intervals. Positional nystagmus is the most common of these abnormalities and can be induced in different positions. The amplitude of these patients' positional nystagmus tends to be low, and the duration tends to be long. Observing changes in eye movements by videonystagmography may be helpful in the diagnosis of VM.