title: Localization of ictal and interictal bursting epileptogenic activity in focal cortical dysplasia: agreement of magnetoencephalography and electrocorticography.
abstract: Focal cortical dysplasia (FCD) is often associated with severe partial epilepsy. In such cases, interictal frequent rhythmic bursting epileptiform activity (FBREA) on both scalp electroencephalography (EEG) and electrocorticography (ECoG) is generally accepted to be identical to the ictal epileptiform activity. We used magnetoencephalography (or Magnetic Source Imaging (MSI)) to determine the epileptogenic zone in a 6-year-old patient with histopathologically proven FCD and normal magnetic resonance imaging (MRI). MSI was used to localize the sources of both ictal activity and FRBEA, which was then compared with ECoG findings. The intracranial sources of both types of activity co-localized in the left inferior frontal and superior temporal gyri. The location and extent of the epileptogenic area determined by MSI was essentially identical to that determined directly through extra-operative ECoG. In the absence of structural abnormalities detectable on MRI, the noninvasive method of MSI provided valuable information regarding the location and extent of the primary epileptogenic area. This was critical for pre-surgical planning regarding placement of intracranial electrodes and for risk-benefit evaluation.
authors.affiliation: Department of Neurosurgery, Vivian L Smith Center for Neurologic Research, The University of Texas Health Science Center at Houston, 77030, USA. Hideaki.Ishibashi@uth.tmc.edu
authors.forename: Hideaki
authors.initials: H
authors.lastname: Ishibashi
authors.forename: Panagiotis G
authors.initials: PG
authors.lastname: Simos
authors.forename: James W
authors.initials: JW
authors.lastname: Wheless
authors.forename: James E
authors.initials: JE
authors.lastname: Baumgartner
authors.forename: Howard L
authors.initials: HL
authors.lastname: Kim
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Castillo
authors.forename: Robert N
authors.initials: RN
authors.lastname: Davis
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Papanicolaou
mesh_terms: D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology*; D002648:Child; D004569:Electroencephalography; D004827:Epilepsy / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography; D015203:Reproducibility of Results