title: Dynamic susceptibility contrast perfusion MR imaging of multiple sclerosis lesions: characterizing hemodynamic impairment and inflammatory activity.
abstract: OBJECTIVE
  Perfusion measurement in multiple sclerosis (MS) may cast light on the disease pathogenesis and lesion development since vascular pathology is frequently demonstrated in the disease. This study was performed to investigate the perfusion characteristics in MS lesions using dynamic susceptibility contrast MR imaging (DSC-MRI) to better understand the hemodynamic changes in MS.
  
  
  METHODS
  Seventeen patients with relapsing-remitting MS were studied with DSC-MRI. Perfusion measurements included cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT), were obtained in enhancing, non-enhancing lesions covered by DSC-MRI and contralateral normal appearing white matter (NAWM) in patients as well as normal white matter in seventeen control subjects.
  
  
  RESULTS
  DSC-MRI data demonstrated reduced perfusion with significantly prolonged MTT (P < 0.001) in lesions and NAWM in patients compared with normal white matter in controls. Compared to contralateral NAWM, enhancing lesions demonstrate increased CBF (P = 0.007) and CBV (P < 0.0001), indicating inflammation-mediated vasodilatation. A K means cluster analysis was performed and identifies approximately 63.8% of non-enhancing lesions (Class 1) with significantly decreased perfusion (P < or = 0.0001) when compared with contralateral NAWM. In contrast, the remainder 36.2% non-enhancing lesions (Class 2) show increased CBV (P = 0.02) in a similar fashion to enhancing lesions and can be observed on quantitative color-coded maps even without blood-brain barrier breakdown.
  
  
  CONCLUSIONS
  DSC-MRI measurements demonstrate potential for investigating hemodynamic abnormalities that are associated with inflammatory activity, lesion reactivity and vascular compromise in MS lesions. Non-enhancing lesions showed both low and high perfusion suggesting microvascular abnormalities with hemodynamic impairment and inflammatory reactivity that cannot be seen on conventional MRI.
authors.affiliation: Department of Radiology, New York University School of Medicine, NY 10016, USA.
authors.forename: Yulin
authors.initials: Y
authors.lastname: Ge
authors.forename: Meng
authors.initials: M
authors.lastname: Law
authors.forename: Glyn
authors.initials: G
authors.lastname: Johnson
authors.forename: Joseph
authors.initials: J
authors.lastname: Herbert
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.forename: Lois J
authors.initials: LJ
authors.lastname: Mannon
authors.forename: Robert I
authors.initials: RI
authors.lastname: Grossman
mesh_terms: D000328:Adult; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology