Clinical evaluation of acute phase nystagmus associated with cerebellar lesions.

To determine the characteristics of acute phase nystagmus in patients with cerebellar lesions, and to identify a useful indicator for differentiating central lesions from peripheral lesions.Acute phase nystagmus and the appearance of neurological symptoms were retrospectively investigated in 11 patients with cerebellar stroke.At the initial visit, there were no patients with vertical nystagmus, direction-changing gaze evoked nystagmus or pure rotatory nystagmus. There were four cases with no nystagmus and seven cases with horizontal nystagmus at the initial visit. There were no neurological symptoms, except for vertigo and hearing loss, in any cases at the initial visit. The direction and type of nystagmus changed with time, and neurological symptoms other than vertigo appeared subsequently to admission.It is important to observe the changes in nystagmus and other neurological findings for the differential diagnosis of central lesions.