Abnormal Eye Movements and the Underlying Pathophysiology Central Vertigo

Abstract

　Differentiation of central from peripheral lesions is important when examining patients with dizziness or vertigo. Nystagmus is one of the most important clues to the differential diagnosis between central and peripheral lesions. It is not rare in patients with central lesions to have no neurologic symptoms other than nystagmus in the acute phase. Direction-changing gaze-evoked nystagmus, upbeat nystagmus, downbeat nystagmus and direction-changing apogeotropic positional nystagmus are known as characteristic findings of central vertigo. In this article, we report a case with direction-changing gaze-evoked nystagmus, a case with upbeat nystagmus, a case with downbeat nystagmus, and a case with direction-changing apogeotropic positional nystagmus, and explain/speculate on the mechanism of nystagmus in each case.