title: Neonatal white matter abnormalities an important predictor of neurocognitive outcome for very preterm children.
abstract: BACKGROUND
  Cerebral white matter abnormalities on term MRI are a strong predictor of motor disability in children born very preterm. However, their contribution to cognitive impairment is less certain.
  
  
  OBJECTIVE
  Examine relationships between the presence and severity of cerebral white matter abnormalities on neonatal MRI and a range of neurocognitive outcomes assessed at ages 4 and 6 years.
  
  
  METHODS
  The study sample consisted of a regionally representative cohort of 104 very preterm (≤32 weeks gestation) infants born from 1998-2000 and a comparison group of 107 full-term infants. At term equivalent, all preterm infants underwent a structural MRI scan that was analyzed qualitatively for the presence and severity of cerebral white matter abnormalities, including cysts, signal abnormalities, loss of white matter volume, ventriculomegaly, and corpus callosal thinning/myelination. At corrected ages 4 and 6 years, all children underwent a comprehensive neurodevelopmental assessment that included measures of general intellectual ability, language development, and executive functioning.
  
  
  RESULTS
  At 4 and 6 years, very preterm children without cerebral white matter abnormalities showed no apparent neurocognitive impairments relative to their full-term peers on any of the domain specific measures of intelligence, language, and executive functioning. In contrast, children born very preterm with mild and moderate-to-severe white matter abnormalities were characterized by performance impairments across all measures and time points, with more severe cerebral abnormalities being associated with increased risks of cognitive impairment. These associations persisted after adjustment for gender, neonatal medical risk factors, and family social risk.
  
  
  CONCLUSIONS
  Findings highlight the importance of cerebral white matter connectivity for later intact cognitive functioning amongst children born very preterm. Preterm born children without cerebral white matter abnormalities on their term MRI appear to be spared many of the cognitive impairments commonly associated with preterm birth. Further follow-up will be important to assess whether this finding persists into the school years.
authors.affiliation: Canterbury Child Development Research Group, Department of Psychology, University of Canterbury, Christchurch, New Zealand. lianne.woodward@canterbury.ac.nz
authors.forename: Lianne J
authors.initials: LJ
authors.lastname: Woodward
authors.forename: Caron A C
authors.initials: CA
authors.lastname: Clark
authors.forename: Samudragupta
authors.initials: S
authors.lastname: Bora
authors.forename: Terrie E
authors.initials: TE
authors.lastname: Inder
mesh_terms: D000328:Adult; D001921:Brain / Q000002:abnormalities* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000473:pathology*; D002658:Developmental Disabilities / Q000473:pathology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007360:Intelligence; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests