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jws-mds.20484.vid.mpg13273K The patient has a masked face. He is unable to look up and can look down only a few degrees during vertical pursuit testing. Horizontal saccades are slow and hypometric. When looking to the left, eye movements become dissociated because abduction of the left eye is slower than adduction of the right eye, which is explained by previous surgery (shortening of the medial rectus muscle on the left). When he attempts to look up, there is brief convergence retraction nystagmus. During vertical vestibulo-ocular reflex testing, there are only minimal up or down shifts of the eyes. Speech is slow and dysarthric, with lack of prosody. There is axial rigidity during both flexion/extension movements and rotation of the neck. Finger movements are slow, and there is some fatiguing. His handwriting is slow but large. He also walks slowly and somewhat wide-based, but stride length and arm swing is normal. His head and neck are held in a fixed straightened position. Postural stability on backward pull test is markedly impaired. This video presentation has been abbreviated. The full version will appear on theMovementDisorders DVD Supplement, which is issued bi-annually.

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