title: Cerebral blood flow measurements in infants using look-locker arterial spin labeling.
abstract: OBJECTIVE
  To measure cerebral blood flow (CBF) using Look-Locker arterial spin labeling (ASL) in children under 1 year of age and to investigate the advantages of using subject-specific estimates of ASL model parameters in this population.
  
  
  METHODS
  Of 12 scanned infants, we successfully acquired CBF maps in 7 (postmenstrual age: 32 to 78 weeks) using a Look-Locker ASL scheme and both adult literature-derived and subject-specific model parameters. ASL global CBF measurements were compared with independent global CBF measurements obtained in the same scanning session using phase-contrast angiography.
  
  
  RESULTS
  Measured global CBF values ranged from 24 to 56 mL/100g/min in the scanned infants, increasing significantly with postmenstrual age (ρSpearman  = 0.89, P-value = 0.01). Using subject-specific model parameters yielded CBF estimates in significantly better agreement with phase-contrast angiography values (P-value: 0.80) than when standard adult parameters were used (P-value: 0.04).
  
  
  CONCLUSIONS
  Look-Locker ASL can be used to measure CBF in infants and its accuracy is improved with the use of infant-specific auxiliary parameters, particularly blood and tissue T1 , which were much more variable in the imaged infants in than adults.
authors.affiliation: Department of Biomedical Engineering, Division of Imaging Sciences, King's College London, London, UK.|Imaging Sciences Department, MRC Clinical Sciences Centre, Imperial College London, London, UK.
authors.forename: Marta
authors.initials: M
authors.lastname: Varela
authors.affiliation: Department of Radiology, University Medical Center, Utrecht, The Netherlands.
authors.forename: Esben T
authors.initials: ET
authors.lastname: Petersen
authors.affiliation: UCL Institute of Neurology, University College London, London, UK.
authors.forename: Xavier
authors.initials: X
authors.lastname: Golay
authors.affiliation: Department of Biomedical Engineering, Division of Imaging Sciences, King's College London, London, UK.|Imaging Sciences Department, MRC Clinical Sciences Centre, Imperial College London, London, UK.
authors.forename: Joseph V
authors.initials: JV
authors.lastname: Hajnal
mesh_terms: D001927:Brain Diseases / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D012680:Sensitivity and Specificity; D013113:Spin Labels
chemical_list: D013113:Spin Labels
keywords: Cerebral perfusion measurements; blood flow quantification; magnetic resonance imaging; neonatal imaging; pediatric neurology and hemodynamics; phase contrast angiography