Focal seizure propagation illustrated by fMRI.

We report the pattern of seizure propagation as detected by functional MRI (fMRI) in a 24-year-old man with frequent recurrent electrographic seizures. The EEG seizure onset was left occipital with later spread to the left hemisphere and, to a lesser extent, the right hemisphere. The fMRI showed initial increase in blood oxygen level-dependent (BOLD) signal in the left occipital pole. The increased signal then propagated to the right occipital-posterotemporal region, and subsequently, the right and left mesial temporal regions. fMRI can be an effective tool to study seizure onset localization and seizure propagation in patients with frequent recurrent seizures.