title: Brain metabolite concentrations are associated with illness severity scores and white matter abnormalities in very preterm infants.
abstract: BACKGROUND
  Magnetic resonance spectroscopy allows for the noninvasive study of brain metabolism and therefore may provide useful information about brain injuries. We examined the associations of brain metabolite ratios in very preterm infants with white matter lesions and overall health status at birth.
  
  
  METHODS
  Spectroscopy data were obtained from 99 very preterm infants (born ≤32 wk gestation) imaged shortly after birth and from 67 of these infants at term-equivalent age. These data were processed using LCModel. Multiple regression was used to examine the association of metabolite ratios with focal noncystic white matter lesions visible on conventional magnetic resonance imaging (MRI) and with at-birth illness severity scores.
  
  
  RESULTS
  Within 2 wk of birth, the ratio of N-acetylaspartate + N-acetylaspartylglutamate to creatine + phosphocreatine was significantly lower in those infants showing white matter abnormalities on conventional MRI. Increased lactate to creatine + phosphocreatine and lactate to glycerophosphocholine + phosphocholine ratios were significantly associated with increasing severity of Clinical Risk Index for Babies II and Apgar scores taken at 1 and 5 min after birth.
  
  
  CONCLUSIONS
  Both overall health status at birth and white matter injury in preterm neonates are reflected in metabolite ratios measured shortly after birth. Long-term follow-up will provide additional insight into the prognostic value of these measures.
authors.affiliation: Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario, Canada. dallas.card@gmail.com
authors.forename: Dallas
authors.initials: D
authors.lastname: Card
authors.forename: Revital
authors.initials: R
authors.lastname: Nossin-Manor
authors.forename: Aideen M
authors.initials: AM
authors.lastname: Moore
authors.forename: Charles
authors.initials: C
authors.lastname: Raybaud
authors.forename: John G
authors.initials: JG
authors.lastname: Sled
authors.forename: Margot J
authors.initials: MJ
authors.lastname: Taylor
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D004151:Dipeptides / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D012720:Severity of Illness Index
chemical_list: D004151:Dipeptides; C027172:isospaglumic acid; D001224:Aspartic Acid; C000179:N-acetylaspartate