Absence of seizures or mirror foci in experimental epilepsy after excision of alumina and astrogliotic scar.

In 15 rhesus monkeys (Macaca mulatta) made epileptic by the sensorimotor cortical injection of alumina, the roles of alumina and of "mirror foci" were investigated by serial surgical excisions of the granuloma, surrounding epileptic focus, and contralateral homotopic sensorimotor cortex. Electroencephalographic and electrocorticographic recordings documented foci and transmitted contralateral epileptic activity. After the granuloma was removed, seizures continued but without alumina. After the epileptic cortex was removed, no seizure activity remained and no contralateral independent foci occurred. These findings indicate that the epilepsy incident to alumina injection into the sensorimotor cortex in monkey is not dependent on the continual presence of alumina and is not associated with independent or "mirror foci."