title: Quantitative susceptibility mapping-based cerebral metabolic rate of oxygen mapping with minimum local variance.
abstract: OBJECTIVE
  The objective of this study was to demonstrate the feasibility of a cerebral metabolic rate of oxygen (CMRO2) mapping method based on its minimum local variance (MLV) without vascular challenge using quantitative susceptibility mapping (QSM) and cerebral blood flow (CBF).
  
  
  METHODS
  Three-dimensional multi-echo gradient echo imaging and arterial spin labeling were performed in 11 healthy subjects to calculate QSM and CBF. Minimum local variance was used to compute whole-brain CMRO2map from QSM and CBF. The MLV method was compared with a reference method using the caffeine challenge. Their agreement within the cortical gray matter (CGM) was assessed on CMRO2and oxygen extraction fraction (OEF) maps at both baseline and challenge states.
  
  
  RESULTS
  Mean CMRO2(in µmol/100 g/min) obtained in CGM using the caffeine challenge and MLV were 142 ± 16.5 and 139 ± 14.8 µmol/100 g/min, respectively; the corresponding baseline OEF were 33.0 ± 4.0% and 31.8 ± 3.2%, respectively. The MLV and caffeine challenge methods showed no statistically significant differences across subjects with small ( < 4%) biases in CMRO2and OEF values.
  
  
  CONCLUSIONS
  Minimum local variance-based CMRO2mapping without vascular challenge using QSM and arterial spin labeling is feasible in healthy subjects. Magn Reson Med 79:172-179, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA.|Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Jingwei
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA.|Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Junghun
authors.initials: J
authors.lastname: Cho
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Dong
authors.initials: D
authors.lastname: Zhou
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Thanh D
authors.initials: TD
authors.lastname: Nguyen
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Pascal
authors.initials: P
authors.lastname: Spincemaille
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Ajay
authors.initials: A
authors.lastname: Gupta
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA.|Department of Radiology, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping / Q000379:methods*; D002110:Caffeine / Q000737:chemistry; D002560:Cerebrovascular Circulation; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging*; D064368:Healthy Volunteers; D006801:Humans; D000860:Hypoxia; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D010100:Oxygen / Q000737:chemistry*; D012016:Reference Values; D055815:Young Adult
chemical_list: D002110:Caffeine; D010100:Oxygen
keywords: OEF; QSM; quantitative CMRO2