title: 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.
authors.affiliation: Department of Neurology, Neurological Institute, Fukuoka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: R
authors.initials: R
authors.lastname: Suga
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.forename: S
authors.initials: S
authors.lastname: Tobimatsu
authors.forename: M
authors.initials: M
authors.lastname: Sasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Kuwabara
authors.forename: H
authors.initials: H
authors.lastname: Furuya
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: J
authors.initials: J
authors.lastname: Kira
mesh_terms: D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives*; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D007866:Leg; D008475:Median Nerve / Q000503:physiopathology; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology*; D009207:Myoclonus / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow; D013979:Tibial Nerve / Q000503:physiopathology; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine