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Research Article| Volume 163, ISSUE 1, P58-60, February 01, 1999

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Idiopathic cortical myoclonus restricted to the lower limbs: correlation between MEPs and 99mTc-ECD single photon emission computed tomography activation study

      Abstract

      We report a 63-year-old woman with cortical reflex myoclonus restricted to the bilateral lower limbs. Somatosensory evoked cortical potentials to posterior tibial nerve stimulation were enlarged with C-responses. Jerk-locked back averaging of the EEG identified a cortical spike related to myoclonic jerks. Motor evoked potentials recorded from the abductor hallucis muscle showed an exaggerated late response. These findings suggest hyperexcitability of the sensorimotor cortex. 99mTc-ECD single photon emission computed tomography (SPECT) after stimulation of the posterior tibial nerve showed increased perfusion in the contralateral peri-Rolandic area which corresponded to the hyperexcitable region. A SPECT activation study as well as MEPs therefore can be employed to determine the hyperexcitable region in cortical myoclonus.

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      References

        • Brown P.
        • Ridding M.C.
        • Werhahn K.J.
        • Rothwell J.C.
        • Marsden C.D.
        Abnormality of the balance between inhibition and excitation in the motor cortex of patients with cortical myoclonus.
        Brain. 1996; 119: 309-317
        • Ibanez V.
        • Deiber M-P.
        • Sadato N.
        • Toro C.
        • Grissom J.
        • Woods R.P.
        • Mazziotta J.C.
        • Hallet M.
        Effect of stimulus rate on regional cerebral blood flow after median nerve stimulation.
        Brain. 1995; 118: 1339-1351
        • Ikeda A.
        • Shibasaki H.
        • Nagamine T.
        • Xu X.
        • Terada K.
        • Mima T.
        • Kaji R.
        • Kawai I.
        • Tatsuoka Y.
        • Kimura J.
        Peri-rolandic and fronto-parietal components of scalp-recorded giant SEPs in cortical myoclonus.
        Electroenceph Clin Neurophysiol. 1995; 96: 300-309
        • Kakigi R.
        • Shibasaki H.
        Somatosensory evoked potentials following stimulation of the lower limb in cortical reflex myoclonus.
        J Neurol Neurosurg Psychiatry. 1987; 50: 1641-1646
        • Kanouchi T.
        • Yokota T.
        • Kamata T.
        • Ishii K.
        • Senda M.
        Central pathway of photic reflex myoclonus.
        J Neurol Neurosurg Psychiatry. 1997; 62: 414-417
        • Shibasaki H.
        • Yamashita Y.
        • Neshige R.
        • Tobimatsu S.
        • Fukui R.
        The pathogenesis of giant somatosensory evoked potentials in progressive myoclonic epilepsy.
        Brain. 1985; 108: 225-240
        • Thompson P.D.
        • Day B.L.
        • Rothwell J.C.
        • Brown P.
        • Britton T.C.
        • Marsden C.D.
        The myoclonus in corticobasal degeneration. Evidence for two forms of cortical reflex myoclonus.
        Brain. 1994; 117: 1197-1207
        • Toro C.
        • Pascual-Leone A.
        • Deuschl G.
        • Tate E.
        • Pranzatelli M.R.
        • Hallett M.
        Cortical tremor. A common manifestation of cortical myoclonus.
        Neurology. 1993; 43: 2346-2353
        • Valeriani M.
        • Restuccia D.
        • Lazzaro V.D.
        • Pera D.L.
        • Tonali P.
        The pathophysiology of giant SEPs in cortical myoclonus: a scalp topography and dipolar source modelling study.
        Electroenceph Clin Neurophysiol. 1997; 104: 122-131