Comparison of independent aura, ictal and interictal cerebral perfusion.

Technetium-HMPAO cerebral SPECT was performed interictally, immediately after an independent aura and ictally in a patient with complex partial seizures. Interictally there was a left inferior frontoparietal region of decreased perfusion. Ictally there were a number of foci of increased perfusion. The aura study showed focal hyperperfusion in the left frontal region and decreased perfusion in the adjacent cortex posteriorly, suggesting a zone of suppression. This may be the cause or effect of the nonprogression of the aura. The case raises the possibility that cerebral perfusion studies performed immediately after independent auras may localize seizure foci if ictal studies are nonfocal.