128-channel EEG source imaging in epilepsy: clinical yield and localization precision.
The authors evaluated the feasibility, clinical yield, and localization precision of high-resolution EEG source imaging of interictal epileptic activity. A consecutive series of 44 patients with intractable epilepsy of various causes, who underwent a comprehensive presurgical epilepsy evaluation, were subjected to a 128-channel EEG recording. A standardized source imaging procedure constrained to the individual gray matter was applied to the averaged spikes of each patient. In 32 patients, the presurgical workup identified a focal epileptogenic area. The 128-channel EEG source imaging correctly localized this area in 30 of these patients (93.7%). Imprecise localization was explained by simplifications of the recordings and analysis procedure, which was accepted for the benefit of speed and standardization. In a subgroup of 24 patients who underwent operations, the sublobar precision of the 128-channel EEG source imaging was evaluated by calculating the distance of the source maximum to the resected area. This analysis revealed zero distance in 19 cases (79%). The authors conclude that high-resolution interictal EEG source imaging is a valuable noninvasive functional neuroimaging technique. The speed, ease, flexibility, and low cost of this technique warrant its use in clinical practice.
Functional Brain Mapping Laboratory, Neurology Clinic, University Hospital, Geneva, Switzerland. christoph.michel@hcuge.ch
Christoph M
CM
Michel
Göran
G
Lantz
Laurent
L
Spinelli
Rolando Grave
RG
De Peralta
Theodor
T
Landis
Margitta
M
Seeck
D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001931:Brain Mapping / Q000295:instrumentation / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004569:Electroencephalography / Q000295:instrumentation / Q000379:methods*; D004827:Epilepsy / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome