title: Increased Cortical Cerebral Blood Flow in Asymptomatic Human Immunodeficiency Virus-Infected Subjects.
abstract: BACKGROUND
  Human immunodeficiency virus (HIV)-infected individuals are at high risk for ischemic stroke. To investigate the physiological basis for this risk, we used magnetic resonance imaging (MRI) to measure oxygen extraction fraction (OEF) and cerebral blood flow (CBF) in treatment-naive asymptomatic HIV-infected subjects and controls.
  
  
  METHODS
  In treatment-naive asymptomatic HIV-infected subjects and age-, gender-, and race-matched controls, OEF was measured by MRI asymmetric spin-echo echo-planar imaging sequences and CBF was measured by MRI pseudocontinuous arterial spin labeling.
  
  
  RESULTS
  Twenty-six treatment-naive HIV-infected subjects and 27 age-, gender-, race-matched controls participated. Whole-brain, gray matter (GM), and white matter OEF were not different between the groups (all P > .70). Unexpectedly, HIV-infected subjects had significantly higher CBF in cortical GM (72.9 ± 16.2 mL/100 g/min versus 63.9 ± 9.9 mL/100 g/min; P = .01) but not in subcortical GM (P = .25).
  
  
  CONCLUSIONS
  The observed increase in cortical GM CBF in treatment-naive HIV-infected subjects is unexpected, contrary to CBF decreases reported in HIV-infected subjects on treatment, and may represent an initial increase in metabolic activity due to an HIV-mediated inflammation.
authors.affiliation: Department of Neurology, University of South Carolina, Columbia, South Carolina. Electronic address: Souvik.Sen@uscmed.sc.edu.
authors.forename: Souvik
authors.initials: S
authors.lastname: Sen
authors.affiliation: Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri.
authors.forename: Hongyu
authors.initials: H
authors.lastname: An
authors.affiliation: Division of Infectious Disease, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: Prema
authors.initials: P
authors.lastname: Menezes
authors.affiliation: Division of Infectious Disease, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Oakes
authors.affiliation: Division of Infectious Disease, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: Joseph
authors.initials: J
authors.lastname: Eron
authors.affiliation: Department of Radiology, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: Weili
authors.initials: W
authors.lastname: Lin
authors.affiliation: Department of Neurology, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: Kevin
authors.initials: K
authors.lastname: Robertson
authors.affiliation: Department of Neurology, University of North Carolina, Chapel Hill, North Carolina.
authors.forename: William
authors.initials: W
authors.lastname: Powers
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology* / Q000821:virology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D005897:Glafenine / Q000008:administration & dosage / Q000031:analogs & derivatives; D015658:HIV Infections / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D013113:Spin Labels; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents; D013113:Spin Labels; D005897:Glafenine; C023803:nicafenine
keywords: Cerebral blood flow measurement; MRI; cerebrovascular disease; infectious disease; inflammation