title: False lateralization of seizure onset by scalp EEG in neocortical temporal lobe epilepsy.
abstract: False lateralization of ictal onset by scalp EEG has been reported in patients with severe hippocampal sclerosis associated with hemispheric lesions or atrophy. There has been no report of cases of false lateralization by scalp EEG in patients without detectable structural abnormalities on MRI, or in patients with neocortical temporal lobe epilepsy. We report a case of false lateralization of ictal onset by scalp EEG in a patient with neocortical temporal lobe epilepsy and a normal MRI examination, investigated by intracranial EEG recordings. The ictal activity failed to propagate in the ipsilateral temporal lobe, but was strongly propagated to the contralateral temporal lobe resulting in a false lateralization of seizure onset by scalp EEG. It is possible that the poor homolateral propagation and evolution of ictal activity in this patient may be due to a functional rather than structural abnormality of the ipsilateral hippocampus, causing reduced synchrony and amplitude in the ipsilateral temporal cortex.
authors.affiliation: Department of Neurology, University of Tennessee Health Science Center, 415 Link Building, 855 Monroe Avenue, Memphis, TN 38163, USA. badamole@uthsc.edu
authors.forename: Bola
authors.initials: B
authors.lastname: Adamolekun
authors.forename: Pegah
authors.initials: P
authors.lastname: Afra
authors.forename: F A
authors.initials: FA
authors.lastname: Boop
mesh_terms: D000654:Amobarbital; D004569:Electroencephalography; D017029:Epilepsy, Complex Partial / Q000150:complications; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality; D018757:GABA Modulators; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019579:Neocortex / Q000503:physiopathology*; D012307:Risk Factors; D012640:Seizures / Q000175:diagnosis / Q000503:physiopathology*
chemical_list: D018757:GABA Modulators; D000654:Amobarbital