Bilateral spike-and-wave discharges in a hemi-deafferented cortex.

We studied a patient with a history of absence attacks in childhood in whom an absence status with bilateral spike-and-wave discharges developed after a top-of-the-basilar syndrome. Surprisingly, even though the ischemic lesion involved the left thalamus alone, spike-and-wave discharges were recorded from the two hemispheres. Three days after antiepileptic treatment (sodium valproate 500mg 3 times a day) began, electroenceplalographic recordings and consciousness became normal.