title: MRI, volumetry, 1H spectroscopy, and cerebropetal blood flowmetry in childhood idiopathic anatomic megalencephaly.
abstract: OBJECTIVE
  To evaluate cerebral abnormalities in childhood idiopathic anatomic megalencephaly (MC) by means of different magnetic resonance (MR) modalities.
  
  
  METHODS
  MRI, volumetry, spectroscopy, and cerebropetal blood flowmetry were performed in six children with idiopathic anatomic MC, and seven volunteers.
  
  
  RESULTS
  MRI revealed an increased ventricular system in five of six patients. A thalamic hamartoma was found in one patient and a Chiari I malformation was found in two. Volumetric analysis showed a disproportional increase of ventricular volume but normal subarachnoid cerebrospinal fluid (CSF) volume. Supratentorial volume was disproportionally increased compared to cerebellar volume. Intracranial volume correlated significantly with skull circumference. MR spectroscopy (MRS) N-acetyl aspartate/choline (NAA/Cho) peak ratios in WM were significantly higher in patients than in controls. Choline/creatine (Cho/Cr) peak ratios in WM were significantly lower in patients. Cortical gray matter (GM) MRS ratios were unaltered. Cerebropetal flow was increased in MC, possibly related to increased brain volume.
  
  
  CONCLUSIONS
  This study reveals associated developmental anomalies for idiopathic anatomic MC. A relative ventriculomegaly was found, which should not be misinterpreted as true hydrocephalus. In contrast to metabolic MC, MRS showed no severe disturbances. Total intracranial volume is correlated to skull circumference and cerebropetal blood flow.
authors.affiliation: Department of Child Neurology, University Medical Centre Utrecht, Utrecht, The Netherlands. s.m.koudijs@umcutrecht.nl
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Koudijs
authors.forename: Jeroen
authors.initials: J
authors.lastname: van der Grond
authors.forename: Mechteld L C
authors.initials: ML
authors.lastname: Hoogendoorn
authors.forename: Hilleke E
authors.initials: HE
authors.lastname: Hulshoff Pol
authors.forename: Hugo G
authors.initials: HG
authors.lastname: Schnack
authors.forename: Theo D
authors.initials: TD
authors.lastname: Witkamp
authors.forename: Rob H J M
authors.initials: RH
authors.lastname: Gooskens
authors.forename: Onno
authors.initials: O
authors.lastname: van Nieuwenhuizen
authors.forename: Kees P J
authors.initials: KP
authors.lastname: Braun
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001783:Blood Flow Velocity; D001921:Brain / Q000002:abnormalities*; D001927:Brain Diseases / Q000378:metabolism / Q000473:pathology*; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D002648:Child; D002675:Child, Preschool; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D005260:Female; D006801:Humans; D006984:Hypertrophy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D009929:Organ Size; D018709:Statistics, Nonparametric
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline