Original article Evolution of brain glucose metabolism with age in epileptic infants, children and adolescents M’hamed Bentourkia a , Christian Michel a , Gerard Ferriere b , Anne Bol a , Ann Coppens a , Merence Sibomana a , Raymond Bausart a , Daniel Labar a , Anne G. De Volder a, * a Positron Tomography Laboratory, University of Louvain, School of Medicine, Chemin du Cyclotron 2, B-1348 Louvain-La-Neuve, Belgium b Pediatric Neurology Service, St Luc Hospital, B-1200 Brussels, Belgium Received 8 December 1997; revised version received 22 May 1998; accepted 25 May 1998 Abstract During the first years of life, the human brain undergoes repetitive modifications in its anatomical, functional, and synaptic construction to reach the complex functional organization of the adult central nervous system. As an attempt to gain further insight in those maturation processes, the evolution of cerebral metabolic activity was investigated as a function of age in epileptic infants, children and adolescents. The regional cerebral metabolic rates for glucose (rCMRGlc) were measured with positron emission tomography (PET) in 60 patients aged from 6 weeks to 19 years, who were affected by complex partial epilepsy. They were scanned at rest, without premedication, in similar conditions to 20 epileptic adults and in 49 adult controls. The distribution of brain metabolic activity successively extended from sensori- motor areas and thalamus in epileptic newborns to temporo-parietal and frontal cortices and reached the adult pattern after 1 year of age. The measured rCMRGlc in the cerebral cortex, excluding the epileptic lesions, increased from low values in infants to a maximum between 4 and 12 years, before it declined to stabilize at the end of the second decade of life. Similar age-related changes in glucose metabolic rates were not observed in the adult groups. Despite the use of medications, the observed variations of rCMRGlc with age in young epileptic humans confirm those previously described in pediatric subjects. These metabolic changes are in full agreement with the current knowledge of the synaptic density evolution in the human brain.  1998 Elsevier Science B.V. All rights reserved Keywords: Positron emission tomography; [F-18]flourodeoxyglucose; Childhood epilepsy; Brain metabolism; Developing brain 1. Introduction Brain maturation in children and adolescents has been studied, among other techniques, by means of positron emission tomography (PET) [1–6] and single photon emis- sion computed tomography [7], through measurements of the regional cerebral blood flow (rCBF) and the regional cerebral metabolic rates for glucose (rCMRGlc). Quantita- tive measurements of rCMRGlc with PET in infants and children revealed post-natal changes in metabolic activity, related to the functional maturation of the brain. Cerebral glucose metabolic rates followed a triphasic evolution char- acterized by rapid increase after birth, persistent high levels during childhood and a subsequent decline, to reach the adult metabolic rates, at the end of adolescence. This increased cerebral energy demand in the developing brain was interpreted as resulting from the known transient synap- tic exuberance related to developmental brain plasticity. Since these studies could not be made on healthy children for ethical reasons, the published data [1–7] were obtained in few subjects with subtle neurological disorders who were considered to be representative of the normal state. In the present work, the mean cortical rCMRGlc was measured in 60 humans aged from 6 weeks to 19 years and affected by complex partial epilepsy. The results obtained in this epi- leptic population indicated a similar developmental evolu- tion in cerebral glucose metabolism as that described previously in ‘normal’ children without definite influence of partial epilepsy. Brain & Development 20 (1998) 524–529 0387-7604/98/$19.00  1998 Elsevier Science B.V. All rights reserved PII S0387-7604(98)00040-0 * Corresponding author. Fax: +32 10 452504; e-mail: devolder@topo.ucl.ac.be