title: White matter hemodynamic abnormalities precede sub-cortical gray matter changes in multiple sclerosis.
abstract: BACKGROUND
  Hypoperfusion has been reported in lesions, normal-appearing white (NAWM) and gray matter (NAGM) of patients with clinically definite multiple sclerosis (MS) by using perfusion MRI. However, it is still unknown how early such changes in perfusion occur. The aim of our study was to assess the presence of hemodynamic changes in the NAWM and subcortical NAGM of patients with clinically isolated syndrome (CIS) in comparison to healthy controls and to patients with early relapsing-remitting (RR) MS.
  
  
  METHODS
  Absolute cerebral blood flow (CBF), blood volume (CBV) and mean transit time (MTT) were measured in the periventricular and frontal NAWM, thalamus and putamen nuclei of 12 patients with CIS, 12 with early RR-MS and 12 healthy controls using dynamic susceptibility contrast enhanced (DSC) T2*-weighted MRI.
  
  
  RESULTS
  Compared to controls, CBF was significantly decreased in the periventricular NAWM of CIS patients and in the periventricular NAWM and putamen of RR-MS patients. Compared to CIS, RR-MS patients showed a significant CBF decrease in the putamen.
  
  
  CONCLUSIONS
  CBF was decreased in the NAWM of both CIS and RR-MS patients and in the subcortical NAGM of RR-MS patients suggesting a continuum of tissue perfusion decreases beginning in white matter and spreading to gray matter, as the disease progresses.
authors.affiliation: Department of Radiology, New York University, New York, NY, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Varga
authors.forename: Glyn
authors.initials: G
authors.lastname: Johnson
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.forename: Joseph
authors.initials: J
authors.lastname: Herbert
authors.forename: Robert I
authors.initials: RI
authors.lastname: Grossman
authors.forename: Matilde
authors.initials: M
authors.lastname: Inglese
mesh_terms: D000328:Adult; D017668:Age of Onset; D001783:Blood Flow Velocity; D001810:Blood Volume; D001921:Brain / Q000098:blood supply* / Q000473:pathology* / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D015331:Cohort Studies; D003711:Demyelinating Diseases / Q000473:pathology / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology* / Q000503:physiopathology*; D009413:Nerve Fibers, Myelinated; D012039:Regional Blood Flow; D013997:Time Factors; D055815:Young Adult