Multiple system atrophy with macrosquare-wave jerks.

Macrosquare-wave jerks consist of high-amplitude saccadic intrusions occurring mainly during fixation that are observed in several disease entities, e.g., multiple sclerosis or parkinsonian syndromes, but very rarely in patients with multiple system atrophy. We present here a patient with multiple system atrophy exhibiting the oculomotor feature of macrosquare-wave jerks.