Ictal single-photon emission computed tomography demonstrates localized epileptogenesis in cortical dysplasia.

We investigated the use of ictal single-photon emission computed tomography (SPECT) in 2 children with intractable epilepsy. Ictal scalp electroencephalographic studies failed to localize the epileptic focus and interictal data demonstrated widespread lateralized abnormalities. Ictal SPECT studies with technetium 99m-hexamethylpropyleneamineoxime demonstrated focal areas of hyperperfusion in the frontal lobes. Resection of the abnormal areas shown by SPECT was carried out despite evidence of large areas of epileptogenesis demonstrated by scalp and subdural electroencephalographic studies. Pathological material revealed cortical dysplasia. Ictal SPECT provides functional evidence for localized epileptogenesis in focal cortical dysplasia.