Forty children were studied with EEG, MRI, and F-fluorodeoxyglucose (FDG)-PET, within one year of their third unprovoked partial seizure, at the Children’s National Medical Center, George Washington University School of Medicine, Washington, DC. The mean age at seizure onset was 5.8 years, mean epilepsy duration 1.1 years, and mean number of seizures 30 (range 3 to 200). An absolute asymmetry index (AI) greater than 0.15 was considered abnormal. Seizure foci were temporal lobe in 33, frontotemporal in 5, and frontal in 2. Mean AI for all regions was not different from that obtained in 10 normal young adults. Focal hypometabolism occurred in 8 (20%), all restricted to the temporal lobe, and ipsilateral to the presumed ictal focus. Cerebral metabolic dysfunction may be more related to persistent epilepsy and is uncommon at onset of a partial seizure disorder. 
COMMENT. Only 20% of children with recent-onset partial epilepsy have PET evidence of temporal hypometabolism. In adults with refractory TLE, the frequency of temporal lobe hypometabolism is 80 to 85%. A follow-up of the patient population is planned by the authors to determine long-term outcome and possible development of metabolic dysfunction with recurrence of seizures.
In a previous study, the authors had examined the effect of valproate on cerebral metabolism by use of PET. . VPA reduced regional cerebral blood flow but not cerebral metabolic rate for glucose in the thalamus. The effect was associated with control of generalized seizures. (see Progress in Pediatric Neurology III, PNB Publishers 1997;pp40-41).