Metabolic Recovery in Caudate Nucleus

I n 3 children who had undergone cerebral hemispherectomy (hemidecortication) between the ages of 1 year 5 months and 4 years for the alleviation of intractable epilepsy, cerebral glucose utilization was studied serially with positron emission tomography. Three to 7 months after hemispherectomy, glucose utilization i n the caudate nuclei on the side of hemispherectomy had decreased to below preoperative values, presumably due to total deprivation of ipsilateral cortical input. O n e to 2.5 years after surgery, complete restoration of glucose metabolic activity to preoperative levels was seen i n 2 patients and partial recovery was seen i n 1 patient. These alterations of cerebral glucose utilization are believed to reflect microscopic anatomical reorganizational changes (e.g., collateral sprouting) that have been documented following similar lesions i n several animal models. O u r findings suggest that positron emission tomography may provide a sensitive measure of developmental brain plasticity in vivo.