title: Comparison of non-invasive MRI measurements of cerebral blood flow in a large multisite cohort.
abstract: Arterial spin labeling and phase contrast magnetic resonance imaging provide independent non-invasive methods for measuring cerebral blood flow. We compared global cerebral blood flow measurements obtained using pseudo-continuous arterial spin labeling and phase contrast in 436 middle-aged subjects acquired at two sites in the NHLBI CARDIA multisite study. Cerebral blood flow measured by phase contrast (CBFPC: 55.76 ± 12.05 ml/100 g/min) was systematically higher (p < 0.001) and more variable than cerebral blood flow measured by pseudo-continuous arterial spin labeling (CBFPCASL: 47.70 ± 9.75). The correlation between global cerebral blood flow values obtained from the two modalities was 0.59 (p < 0.001), explaining less than half of the observed variance in cerebral blood flow estimates. Well-established correlations of global cerebral blood flow with age and sex were similarly observed in both CBFPCASL and CBFPC CBFPC also demonstrated statistically significant site differences, whereas no such differences were observed in CBFPCASL No consistent velocity-dependent effects on pseudo-continuous arterial spin labeling were observed, suggesting that pseudo-continuous labeling efficiency does not vary substantially across typical adult carotid and vertebral velocities, as has previously been suggested.
  
  
  
  Although CBFPCASL and CBFPC values show substantial similarity across the entire cohort, these data do not support calibration of CBFPCASL using CBFPC in individual subjects. The wide-ranging cerebral blood flow values obtained by both methods suggest that cerebral blood flow values are highly variable in the general population.
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA Center for Functional Neuroimaging, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Sudipto
authors.initials: S
authors.lastname: Dolui
authors.affiliation: Center for Cognition and Brain Disorders and the Affiliated Hospital, Hangzhou Normal University, Hangzhou, China Departments of Psychiatry and Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Ze
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Neurology, University of California, Los Angeles, CA, USA.
authors.forename: Danny J J
authors.initials: DJJ
authors.lastname: Wang
authors.affiliation: Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Raghav
authors.initials: R
authors.lastname: Mattay
authors.affiliation: School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Mack
authors.initials: M
authors.lastname: Finkel
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Elliott
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Desiderio
authors.affiliation: Henry H. Wheeler Jr. Brain Imaging Center, University of California, Berkeley, CA, USA.
authors.forename: Ben
authors.initials: B
authors.lastname: Inglis
authors.affiliation: Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Bryon
authors.initials: B
authors.lastname: Mueller
authors.affiliation: Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Randall B
authors.initials: RB
authors.lastname: Stafford
authors.affiliation: Laboratory of Epidemiology and Population Science, National Institute on Aging, Bethesda, MD, USA.
authors.forename: Lenore J
authors.initials: LJ
authors.lastname: Launer
authors.affiliation: Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: R Nick
authors.initials: RN
authors.lastname: Bryan
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA Center for Functional Neuroimaging, University of Pennsylvania, Philadelphia, PA, USA detre@mail.med.upenn.edu.
authors.forename: John A
authors.initials: JA
authors.lastname: Detre
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D002536:Cerebral Arteries / Q000000981:diagnostic imaging* / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D015331:Cohort Studies; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media
keywords: Cerebral blood flow; labeling efficiency; phase contrast magnetic resonance imaging; pseudo-continuous arterial spin labeling; semi-automated vessel segmentation