Multiple System Atrophy

Ataxia of the limbs generally occurs first, predominantly in patients with olivopontocerebellar-type of multiple system atrophy. This leads to gait disturbance. Ataxia in these patients is of cerebellar origin and this can progress to other cerebellar signs, which include dysarthria (speech impairment), and myoclonus (jerking movement of muscles). Abnormalities of eye movements of the cerebellar origin also occur, such as nystagmus (involuntary movements of the eyeball). Examination of the eye movements is important in terms of diagnosis because supranuclear vertical gaze abnormalities, that is, inability to move eyes voluntarily, particularly downward, would be consistent with a diagnosis of progressive supranuclear palsy rather than multiple system atrophy.