Abstract

Positional/positioning nystagmus occurs predominantly with specific head positions. The nystagmus can be attributed to either peripheral or central vestibular dysfunction. Benign paroxysmal postional vertigo (BPPV) is by far the most common cause of the nystagmus, accounting for about 90% of patients. Most central forms of positional vertigo involve the region around the vestibular nuclei and a neuronal loop to the cerebellar vermis. Positional/positioning tests should be performed in all patients with vertigo.