INFANTILE SPASMS WITH PREDOMINANTLY UNILATERAL CEREBRAL ABNORMALITIES

To investigate the pathogenesis of infantile spasms, 12 children under went a combination of neurophysiologic and neuroimaging studies includ ing brainstem evoked potentials and single photon emission computed to mography with (99m)TcHMPAO. Three of the children had localized cerebr al abnormalities on neuroimaging, i. e. right frontotemporal cortical microdysgenesis, left frontotemporal polymicrogyria, and right parieto occipitotemporal porencephalic cyst. Neurophysiologic studies also ind icated that a single cerebral hemisphere was predominantly involved, w hile the other hemisphere and the brainstem were relatively spared, a result compatible with the clinical findings of hemiparesis and hemico nvulsion. In these three patients, administration of carbamazepine was followed by marked improvement of the clinical and electroencephalogr aphic findings. Our results suggest that a combination of noninvasive examinations can distinguish a particular subtype of infantile spasms associated with a localized cerebral abnormality and responsive to car bamazepine.