title: Aetiology of cognitive impairment in children with frontal lobe epilepsy.
abstract: OBJECTIVE
  Cognitive impairment is frequent in children with frontal lobe epilepsy (FLE), but its aetiology is unknown. MRI scans often reveal no structural brain abnormalities that could explain the cognitive impairment. This does not exclude more subtle morphological abnormalities that can only be detected by automated morphometric techniques.
  
  
  OBJECTIVE
  With these techniques, we investigate the relationship between cortical brain morphology and cognitive functioning in a cohort of children with FLE and healthy controls.
  
  
  METHODS
  Thirty-four children aged 8-13 years with FLE of unknown cause and 41 healthy age-matched controls underwent neuropsychological assessment and structural brain MRI. Patients were grouped as cognitively impaired or unimpaired. Intracranial volume, white matter volume, lobular cortical volume, cortical thickness and volumes of cortex structures were compared between patients and controls, and potential correlations with cognitive status were determined.
  
  
  RESULTS
  The group of cognitively impaired children with FLE had significantly smaller left temporal cortex volumes, specifically middle temporal grey matter volume and entorhinal cortex thickness. In addition, cognitively impaired children with FLE had smaller volumes of structures in the left and right frontal cortex, right temporal cortex and the left subcortical area.
  
  
  CONCLUSIONS
  Cognitively impaired children with FLE have smaller volumes of various cortex structures within the frontal lobes and in extra-frontal regions, most notably temporal cortex volumes. These findings might well explain the broad scale of cognitive domains affected in children with FLE complicated by cognitive impairment and highlight that FLE impacts on areas beyond the frontal lobe.
authors.affiliation: Department of Neurology, Maastricht University Medical Centre, Maastricht, the Netherlands; Research School for Mental Health & Neuroscience, Maastricht University Medical Centre, Maastricht, the Netherlands; Department of Research and Development, Epilepsy Centre Kempenhaeghe, Heeze, the Netherlands.
authors.forename: H M H
authors.initials: HM
authors.lastname: Braakman
authors.forename: M J
authors.initials: MJ
authors.lastname: Vaessen
authors.forename: J F A
authors.initials: JF
authors.lastname: Jansen
authors.forename: M H J A
authors.initials: MH
authors.lastname: Debeij-van Hall
authors.forename: A
authors.initials: A
authors.lastname: de Louw
authors.forename: P A M
authors.initials: PA
authors.lastname: Hofman
authors.forename: J S H
authors.initials: JS
authors.lastname: Vles
authors.forename: A P
authors.initials: AP
authors.lastname: Aldenkamp
authors.forename: W H
authors.initials: WH
authors.lastname: Backes
mesh_terms: D000293:Adolescent; D001921:Brain / Q000473:pathology*; D002648:Child; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology*; D017034:Epilepsy, Frontal Lobe / Q000150:complications* / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests
keywords: MRI; all epilepsy/seizures; all paediatric; neuropsychological assessment; volumetric MRI