title: Electroencephalogram-triggered functional magnetic resonance imaging in focal epilepsy.
abstract: The high spatial resolution and cost performance of functional magnetic resonance imaging (fMRI) is useful for estimating focus localization in epilepsy, but this is difficult in the case of ictal fMRI because this is susceptible to motion artifacts. Electroencephalogram (EEG)-triggered fMRI, which is interictal, can be performed without marked movement and is thought to be useful, but requires further investigation in order to establish a methodology. The authors studied EEG-triggered fMRI in partial epileptic patients. Six patients were examined using a Nihon Kohden digital EEG recorder and Signa Horizon High Speed LX 1.5 T MRI scanner. Six electrodes were attached in the vicinity of the focus detected by scalp EEG. The fMRI scans were recorded after the discharges (activation) and scans without spikes (baseline). Equal numbers of activation and baseline scans were collected and analyzed using SPM99. In three of the six patients, an activated area was observed near the focus, but no activated areas were found in the other three subjects who tended to have a low number of spikes and low spike amplitude. Although various approaches focusing on improvement of the activation/non-activation ratio are required, EEG-triggered fMRI is a promising technique for detecting focal epileptic brain activity.
authors.affiliation: Department of Psychiatry, Jichi Medical School, Tochigi, Japan. skikuchi@jichi.ac.jp
authors.forename: Senichiro
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Fumio
authors.initials: F
authors.lastname: Kubota
authors.forename: Koichi
authors.initials: K
authors.lastname: Nishijima
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Hirai
authors.forename: Sumio
authors.initials: S
authors.lastname: Washiya
authors.forename: Junya
authors.initials: J
authors.lastname: Fukuda
authors.forename: Akio
authors.initials: A
authors.lastname: Takahashi
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Shibata
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kato
mesh_terms: D000293:Adolescent; D000328:Adult; D002560:Cerebrovascular Circulation / Q000502:physiology; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged