title: Unique Distribution of Benzodiazepine Receptors in the Brain during the First Two Years of Life.
abstract: BACKGROUND
  123I-iomazenil (IMZ) single-photon emission computed tomography (SPECT) is a tool for evaluating epileptic foci and brain damage. To apply the method to children, information regarding the age-specific expression of benzodiazepine receptors (BDZ-Rs) is required. Unfortunately, there is no information currently available for children <2 years of age.
  
  
  METHODS
  We used IMZ SPECT once in infants aged 3-8 months and again at 2 years of age in order to describe the maturational changes in BDZ-R distribution.
  
  
  RESULTS
  No neurological deficits were found in any of the infants at the first examination. The BDZ-Rs were more dominantly distributed in the occipital lobe than in the frontal lobe before the age of 2 years. The frontal-occipital gradients of the distribution were obvious in children <8 months of age. Magnetic resonance imaging showed a spreading of myelination toward the frontal lobes simultaneously with BDZ-R expression.
  
  
  CONCLUSIONS
  Information regarding the alteration in the BDZ-R distribution pattern is useful when assessing infantile epilepsy and brain injury. The age-related pattern of BDZ-R distribution could correspond with myelination, cerebral blood flow, metabolism and behavioral development.
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi University, Ube, Japan.
authors.forename: Sadahiro
authors.initials: S
authors.lastname: Nomura
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Koizumi
authors.forename: Eiichi
authors.initials: E
authors.lastname: Suehiro
authors.forename: Hidekatsu
authors.initials: H
authors.lastname: Kiya
authors.forename: Michiyasu
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D001345:Autoradiography / Q000379:methods; D001569:Benzodiazepines / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002675:Child, Preschool; D005260:Female; D005442:Flumazenil / Q000031:analogs & derivatives / Q000378:metabolism; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D007223:Infant; D007457:Iodine Radioisotopes / Q000378:metabolism; D008297:Male; D009778:Occipital Lobe / Q000000981:diagnostic imaging / Q000378:metabolism; D011963:Receptors, GABA-A / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D007457:Iodine Radioisotopes; D011963:Receptors, GABA-A; D001569:Benzodiazepines; D005442:Flumazenil; C063038:iomazenil