SEIZURE SYMPTOMATOLOGY IN INFANTS WITH LOCALIZATION-RELATED EPILEPSY

The clinical characteristics of seizures in adults and children with l ocalization-related epilepsy have been clearly described and classifie d, but few data are available based on video EEG studies of postneonat al infants under 2 years of age. We analyzed 125 videotaped seizures f rom 23 infants aged 2 to 24 months with localization-related epilepsy defined by localized ictal EEG or localized lesion on neuroimaging wit h seizure-free surgical outcome. Seizure symptomatology was classified based on observable behavioral and motor manifestations and then corr elated with location of the epileptogenic zone. Seizures characterized by decrease in behavioral motor activity with indeterminate level of consciousness and minimal or no automatisms (''hypomotor'' seizures) a rose from temporal, temporoparietal, or parieto-occipital regions (7 p atients). Seizures with localized or bilateral clonic, tonic, or atoni c motor phenomena arose predominantly from frontal, frontocentral, cen tral, or frontoparietal areas (12 patients). One patient had versive s eizures arising from the contralateral occipital lobe, 2 patients had infantile spasms (one with a frontal tumor, one with temporo-parieto-o ccipital dysplasia), and one patient had unclassifiable seizures. Disr uption of temporal or temporoparietal function resulted primarily in d iminution of behavioral activity, whereas ictal activation of motor ar eas during frontal or central onset seizures resulted mainly in locali zed or generalized motor phenomena. Infantile spasms occurred because of lesions in either location. Using an approach based on easily obser vable behavioral and motor phenomena, it was possible to classify the seizures in all but one infant.