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. 2018 Feb 20;90(8):e647-e657.
doi: 10.1212/WNL.0000000000004996. Epub 2018 Jan 19.

Electrophysiologic testing aids diagnosis and subtyping of myoclonus

Rodi Zutt  1 , Jan W Elting  1 , Jonathan C van Zijl  1 , J Han van der Hoeven  1 , Christiaan M Roosendaal  1 , Jeannette M Gelauff  1 , Kathryn J Peall  1 , Marina A J Tijssen  2
Affiliations

Electrophysiologic testing aids diagnosis and subtyping of myoclonus

Rodi Zutt et al. Neurology. .

Abstract

Objective: To determine the contribution of electrophysiologic testing in the diagnosis and anatomical classification of myoclonus.

Methods: Participants with a clinical diagnosis of myoclonus were prospectively recruited, each undergoing a videotaped clinical examination and battery of electrophysiologic tests. The diagnosis of myoclonus and its subtype was reviewed after 6 months in the context of the electrophysiologic findings and specialist review of the videotaped clinical examination.

Results: Seventy-two patients with myoclonus were recruited. Initial clinical anatomical classification included 25 patients with cortical myoclonus, 7 with subcortical myoclonus, 2 with spinal myoclonus, and 15 with functional myoclonic jerks. In 23 cases, clinical anatomical classification was not possible because of the complexity of the movement disorder. Electrophysiologic testing was completed in 66, with agreement of myoclonus in 60 (91%) and its subtype in 28 (47%) cases. Subsequent clinical review by a movement disorder specialist agreed with the electrophysiologic findings in 52 of 60; in the remaining 8, electrophysiologic testing was inconclusive.

Conclusions: Electrophysiologic testing is an important additional tool in the diagnosis and anatomical classification of myoclonus, also aiding in decision-making regarding therapeutic management. Further development of testing criteria is necessary to optimize its use in clinical practice.

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Figures

Figure 1
Figure 1. Overview of the stages of clinical assessment and diagnosis undertaken in this study
CM = cortical myoclonus; FJ = functional jerks; MD = movement disorder; MMS = multiple myoclonus subtypes; SCM = subcortical myoclonus; SM = spinal myoclonus.
See this image and copyright information in PMC

References

    1. van der Salm SM, de Haan RJ, Cath DC, van Rootselaar AF, Tijssen MA. The eye of the beholder: inter-rater agreement among experts on psychogenic jerky movement disorders. J Neurol Neurosurg Psychiatry 2013;7:742–747. - PubMed
    1. Erro R, Bhatia KP, Edwards MJ, Farmer SF, Cordivari C. Clinical diagnosis of propriospinal myoclonus is unreliable: an electrophysiologic study. Mov Disord 2013;28:1868–1873. - PubMed
    1. Esposito M, Edwards MJ, Bhatia KP, Brown P, Cordivari C. Idiopathic spinal myoclonus: a clinical and neurophysiological assessment of a movement disorder of uncertain origin. Mov Disord 2009;24:2344–2349. - PubMed
    1. Shibasaki H, Nakamura M, Nishida S, Kakigi R, Ikeda A. Wave form decomposition of “giant SEP” and its computer model for scalp topography. Electroencephalogr Clin Neurophysiol 1990;77:286–294. - PubMed
    1. Shibasaki H, Hallett M. What is the Bereitschaftspotential? Clin Neurophysiol 2006;117:2341–2356. - PubMed

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