Epileptic seizures and structural abnormalities in a patient with holoprosencephaly.

In a patient with holoprosencephaly, partial seizures had various initial ictal symptoms, and ictal EEGs showed epileptogenic foci in the right and left brain. Partial seizures did not culminate in secondary generalized tonic-clonic convulsions. Characteristic malformed structures contribute to the absence of secondary generalization and the presence of Jacksonian-type propagation.