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jws-mds.20725.mpg13421K Segment 1. Shown is the propositus, a 45-year-old man presenting asymmetric postural and action distal myoclonic tremor. Standing and outstretched posture are impaired. Segment 2. The same patient improved by sodium valproate and levetiracetam. There remains a slight myoclonic tremor. Segment 3. The sister of the propositus, a 44-year-old woman. Examination shows a postural tremor without evidence of myoclonus, under sodium valproate. Segment 4. The brother of the propositus, a non-treated 42-year-old man. Examination shows a few myoclonic jerks and a slight postural tremorThis video presentation has been abbreviated. The full version will appear on theMovementDisorders DVD Supplement, which is issued bi-annually.

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