Simultaneous EEG-fMRI in drug-naive children with newly diagnosed absence epilepsy.
OBJECTIVE
In patients with idiopathic generalized epilepsy (IGE), blood oxygen level dependent (BOLD) EEG during functional MRI (EEG-fMRI) has been successfully used to link changes in regional neuronal activity to the occurrence of generalized spike-and-wave (GSW) discharges. Most EEG-fMRI studies have been performed on adult patients with long-standing epilepsy who were on antiepileptic medication. Here, we applied EEG-fMRI to investigate BOLD signal changes during absence seizures in children with newly diagnosed childhood absence epilepsy (CAE).


METHODS
Ten drug-naive children with newly diagnosed CAE underwent simultaneous EEG-fMRI. BOLD signal changes associated with ictal EEG activity (i.e., periods of three per second GSW) were analyzed in predefined regions-of-interests (ROIs), including the thalamus, the precuneus, and caudate nucleus.


RESULTS
In 6 out of 10 children, EEG recordings showed periods of three per second GSW during fMRI. Three per second GSW were associated with regional BOLD signal decreases in parietal areas, precuneus, and caudate nucleus along with a bilateral increase in the BOLD signal in the medial thalamus. Taking into account the normal delay in the hemodynamic response, temporal analysis showed that the onset of BOLD signal changes coincided with the onset of GSW.


CONCLUSIONS
In drug-naive individuals with CAE, ictal three per second GSW are associated with BOLD signal changes in the same striato-thalamo-cortical network that changes its regional activity during primary and secondary generalized paroxysms in treated adults. No BOLD signal changes in the striato-thalamo-cortical network preceded the onset of three per second GSW in unmediated children with CAE.
Moeller
Friederike
F
Department of Neuropediatrics, Christian-Albrechts-University, Kiel, Germany. f.moeller@pedneuro.uni-kiel.de
Siebner
Hartwig R
HR
Wolff
Stephan
S
Muhle
Hiltrud
H
Granert
Oliver
O
Jansen
Olav
O
Stephani
Ulrich
U
Siniatchkin
Michael
M
D001921:Brain / Q000033:anatomy & histology* / Q000503:physiopathology*; D002421:Caudate Nucleus / Q000503:physiopathology; D002648:Child; D004569:Electroencephalography; D004832:Epilepsy, Absence / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D009415:Nerve Net / Q000503:physiopathology; D010100:Oxygen / Q000097:blood; D012720:Severity of Illness Index; D013788:Thalamus / Q000503:physiopathology
D010100:Oxygen