title: Regional Frontal Perfusion Deficits in Relapsing-Remitting Multiple Sclerosis with Cognitive Decline.
abstract: OBJECTIVE
  Cortical dysfunction, quantifiable by cerebral perfusion techniques, is prevalent in patients with MS, contributing to cognitive impairment. We sought to localize perfusion distribution differences in patients with relapsing-remitting MS with and without cognitive impairment and healthy controls.
  
  
  METHODS
  Thirty-nine patients with relapsing-remitting MS (20 cognitively impaired, 19 nonimpaired) and 19 age- and sex-matched healthy controls underwent a neurocognitive battery and MR imaging. Voxel-based analysis compared regional deep and cortical GM perfusion and volume among the cohorts.
  
  
  RESULTS
  After we adjusted for localized volumetric differences in the right frontal, temporal, and occipital lobes, progressive CBF and CBV deficits were present in the left middle frontal cortex for all cohorts and in the left superior frontal gyrus for patients with cognitive impairment compared with patients without impairment and controls. Compared with healthy controls, reduced CBF was present in the limbic regions of patients with cognitive impairment, and reduced CBV was present in the right middle frontal gyrus in patients with cognitive impairment and in the temporal gyrus of relapsing-remitting MS patients without cognitive impairment.
  
  
  CONCLUSIONS
  Consistent regional frontal cortical perfusion deficits are present in patients with relapsing-remitting MS, with more widespread hypoperfusion in those with cognitive impairment, independent of structural differences, indicating that cortical perfusion may be a useful biomarker of cortical dysfunction and cognitive impairment in MS.
authors.affiliation: Medical Imaging (R.V., S.-P.H., L.Z., R.I.A.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada rita.vitorino@sunnybrook.ca.
authors.forename: R
authors.identifier: http://orcid.org/0000-0001-6416-6278
authors.initials: R
authors.lastname: Vitorino
authors.affiliation: Medical Imaging (R.V., S.-P.H., L.Z., R.I.A.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.|Medical Imaging (S.-P.H., R.I.A.), University of Toronto, Toronto, Ontario, Canada.
authors.forename: S-P
authors.identifier: http://orcid.org/0000-0003-0188-1578
authors.initials: SP
authors.lastname: Hojjat
authors.affiliation: Departments of Biomedical Engineering (C.G.C., T.J.C).
authors.forename: C G
authors.identifier: http://orcid.org/0000-0003-0559-8681
authors.initials: CG
authors.lastname: Cantrell
authors.affiliation: From the Departments of Psychiatry (A.F.).|Psychiatry (A.F.).
authors.forename: A
authors.identifier: http://orcid.org/0000-0002-0132-0909
authors.initials: A
authors.lastname: Feinstein
authors.affiliation: Medical Imaging (R.V., S.-P.H., L.Z., R.I.A.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
authors.forename: L
authors.identifier: http://orcid.org/0000-0002-5882-6070
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Neurology (L.L.).|Departments of Medicine (L.L., P.O.).
authors.forename: L
authors.identifier: http://orcid.org/0000-0001-7322-9672
authors.initials: L
authors.lastname: Lee
authors.affiliation: Departments of Medicine (L.L., P.O.).
authors.forename: P
authors.identifier: http://orcid.org/0000-0002-5632-8385
authors.initials: P
authors.lastname: O'Connor
authors.affiliation: Departments of Biomedical Engineering (C.G.C., T.J.C).|Radiology (T.J.C.), Northwestern University, Chicago, Illinois.
authors.forename: T J
authors.identifier: http://orcid.org/0000-0002-5149-8377
authors.initials: TJ
authors.lastname: Carroll
authors.affiliation: Medical Imaging (R.V., S.-P.H., L.Z., R.I.A.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.|Medical Imaging (S.-P.H., R.I.A.), University of Toronto, Toronto, Ontario, Canada.
authors.forename: R I
authors.identifier: http://orcid.org/0000-0003-0259-970X
authors.initials: RI
authors.lastname: Aviv