EEG–fMRI validation studies in comparison with icEEG: A review

Simultaneous EEG–fMRI is a non-invasive investigation technique developed to localize the generators of interictal epileptiform discharges (IED) in patients with epilepsy. Although the value of EEG–fMRI in epilepsy presurgical evaluation is being assessed clinically, its utility is still controversial. In this review, we considered EEG–fMRI applications in epilepsy presurgical evaluation with a focus on validation studies that compared the results of EEG–fMRI with those of the current “gold standard” intracranial EEG (icEEG) in order to assess its utility of seizure focus localization and the possibility for EEG–fMRI to reduce the need for invasive techniques such as icEEG. Since the advances of EEG–fMRI partially rely on the maturation of its data analysis, we also reviewed the methodological developments in EEG–fMRI analysis. It is possible that combining with other neuroimaging modalities such as MEG/MSI and ESI, EEG–fMRI may play a greater role in epilepsy presurgical evaluation.

► The clinical value of EEG–fMRI in epilepsy presurgical evaluation is controversial.
► EEG–fMRI validation studies have been reviewed in this paper.
► EEG–fMRI may play a greater role in epilepsy presurgical evaluation.