References for this review were identified by searches of MEDLINE between January 1, 1996 and April 1, 2004 and references from relevant articles; numerous articles were also identified through searches of the extensive files of the authors. The search terms “myoclonus”, “myoclonic epilepsy”, “myoclonic seizures”, “treatment”, “piracetam”, “levetiracetam”, “diagnosis”, “therapy” were used. Abstracts and reports from meetings were also included. Only papers published in English were
ReviewMyoclonus: current concepts and recent advances
Section snippets
Epidemiology
Only a few large inclusive clinical series have been reported. Among these series, the demographics and relative proportions of different diagnostic categories varies substantially.3 Even so, these studies show that symptomatic (secondary) causes of myoclonus are most common, epileptic seizures and myoclonus are intertwined, and essential (primary and non-progressive) myoclonus only constitutes a small proportion of patients with myoclonus. The only epidemiological study on myoclonus due to any
Clinical presentation and aetiology
The best possible clinical presentations of myoclonus are best organised by use of the major clinical syndrome categories of Marsden and colleagues1 and their corresponding lists of known causes (panel 1). The myoclonus presenting from the causes under a given category will share syndrome properties corresponding to that category. However, the same category may contain forms of myoclonus with various physiological properties. Furthermore, the same causal factor may produce vastly different
Assessment and clinical neurophysiology
The guidelines for the assessment of a patient with myoclonus may be broken up into four parts (panel 3).
Pathophysiology
Results from clinical neurophysiology testing give important insight into the generation of the myoclonus. However, other considerations should be realised about the pathophysiology of myoclonus. The clinical features of myoclonus are largely determined by the nature of the affected motor systems. Thus, cortical myoclonus predominantly affects those body parts with the biggest cortical representations, the hands and face, and, as the motor areas of the cerebral cortex are most involved in
Treatment
The best strategy for the treatment of myoclonus is, of course, the treatment of the underlying disorder. Some causes of myoclonus can be reversed partially or totally, such as an acquired abnormal metabolic state, a medication or toxin, or an excisable lesion. There is some evidence that psychogenic jerks respond to psychotherapy and pharmacological psychiatric treatment.50, 59 However, in most myoclonus cases, such treatment of the underlying disorder is not possible. Ideally, an approach to
Conclusion
Myoclonus has seen tremendous progress in recent years with regard to description of myoclonus syndromes, clinical neurophysiology, and pathophysiology. Despite this progress, this disabling movement disorder still awaits more major advances before better treatments are more widely available. Physicians desperately need treatments specifically designed for myoclonus rather than those intended for other disorders. Further discovery of genetic mutations will yield more specific information with
Search strategy and selection criteria
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