title: Juvenile myoclonic epilepsy--neuroimaging findings.
abstract: Juvenile myoclonic epilepsy (JME) has been classified as a syndrome of idiopathic generalized epilepsy and is characterized by specific types of seizures, showing a lack of pathology using magnetic resonance imaging (MRI) and computed tomography scanning. However, JME is associated with a particular personality profile, and behavioral and neuropsychological studies have suggested the possible involvement of frontal lobe dysfunction. The development of highly sensitive neuroimaging techniques has provided a means of elucidating the underlying mechanisms of JME. Positron emission tomography demonstrated metabolic and neurotransmitter changes in the dorsolateral prefrontal cortex reflecting the particular cognitive and behavioral profile of JME patients. (1)H-magnetic resonance spectroscopy has shown evidence of thalamic dysfunction, which appears to be progressive. Such techniques provide evidence of multi-focal disease mechanisms, suggesting that JME is a frontal lobe variant of a multi-regional, thalamocortical 'network' epilepsy, rather than a generalized epilepsy syndrome. Quantitative MRI revealed significant abnormalities of cortical gray matter in medial frontal areas close to the supplementary motor area and diffusion abnormalities with increased functional coupling between the motor and prefrontal cognitive systems. This altered structural connectivity of the supplementary motor area provides an explanatory framework for the particular imaging findings, seizure type, and seizure-provoking mechanisms in JME.
authors.affiliation: Department of Clinical Experimental Epilepsy, Institute of Neurology, University College London, London, UK. m.koepp@ucl.ac.uk
authors.forename: Matthias J
authors.initials: MJ
authors.lastname: Koepp
authors.forename: Friedrich
authors.initials: F
authors.lastname: Woermann
authors.forename: Ivanka
authors.initials: I
authors.lastname: Savic
authors.forename: Britta
authors.initials: B
authors.lastname: Wandschneider
mesh_terms: D000927:Anticonvulsants / Q000494:pharmacology / Q000627:therapeutic use; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D001931:Brain Mapping; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020190:Myoclonic Epilepsy, Juvenile / Q000175:diagnosis* / Q000188:drug therapy; D059906:Neuroimaging; D011877:Radionuclide Imaging
chemical_list: D000927:Anticonvulsants