Connectivity in ictal single photon emission computed tomography perfusion: a cortico-cortical evoked potential study

Ictal SPECT is used in presurgical evaluations of refractory epilepsy. Tousseyn et al. examine whether ictal perfusion changes correspond to electrically connected networks. Using evoked responses following direct electrical stimulation during stereo-electroencephalography as a connectivity measure, they show that ictal perfusion is not random but is supported by underlying connectivity.