Computerized tomography (CT) was performed on 256 children with seizure disorders. The incidence of abnormal scans was closely related to seizure type, and permitted separation of patients into a low-yield and a high-yield group. Low-yield groups included children with idiopathic generalized seizures, children in whom both the neurologic examination and electroencephalogram (EEG) were normal, and children with a generalized seizure of unknown etiology in whom the neurologic examination and the EEG were normal. The high-yield groups included children with partial seizures with elementary symptomatology, partial seizures with complex symptomatology, generalized seizures with known etiology, neonates with seizures, and children whose seizures began as neonates.
The overall incidence of abnormalities in the entire group was 33 percent. An abnormal neurologic examination increased the incidence of abnormal CT scans to 64 percent. EEGs were abnormal in 65 percent of the children, but only focal slowing resulted in a significant increase in the incidence of abnormal CT scans. Seven children (2.7 percent) had intracranial abnormalities requiring surgery. If the neurologic examination and EEG were normal, the yield of abnormal CT scans was only 5 percent of the total.