title: The Contribution of Cortical Lesions to a Composite MRI Scale of Disease Severity in Multiple Sclerosis.
abstract: OBJECTIVE
  To test a new version of the Magnetic Resonance Disease Severity Scale (v.3 = MRDSS3) for multiple sclerosis (MS), incorporating cortical gray matter lesions (CLs) from 3T magnetic resonance imaging (MRI).
  
  
  BACKGROUND
  MRDSS1 was a cerebral MRI-defined composite scale of MS disease severity combining T2 lesion volume (T2LV), the ratio of T1 to T2LV (T1/T2), and whole brain atrophy [brain parenchymal fraction (BPF)]. MRDSS2 expanded the scale to include cerebral gray matter fraction (GMF) and upper cervical spinal cord area (UCCA). We tested the contribution of CLs to the scale (MRDSS3) in modeling the MRI relationship to clinical status.
  
  
  METHODS
  We studied 51 patients [3 clinically isolated syndrome, 43 relapsing-remitting, 5 progressive forms, age (mean ± SD) 40.7 ± 9.1 years, Expanded Disability Status Scale (EDSS) score 1.6 ± 1.7] and 20 normal controls by high-resolution cerebrospinal MRI. CLs required visibility on both fluid-attenuated inversion-recovery (FLAIR) and modified driven equilibrium Fourier transform sequences. The MACFIMS battery defined cognitively impaired (n = 18) vs. preserved (n = 33) MS subgroups.
  
  
  RESULTS
  EDSS significantly correlated with only BPF, UCCA, MRDSS2, and MRDSS3 (all p < 0.05). After adjusting for depressive symptoms, the cognitively impaired group had higher severity of MRI metrics than the cognitively preserved group in regard to only BPF, GMF, T1/T2, MRDSS1, and MRDSS2 (all p < 0.05). CL number was not significantly related to EDSS score or cognition status.
  
  
  CONCLUSIONS
  CLs from 3T MRI did not appear to improve the validity of the MRDSS. Further studies employing advanced sequences or higher field strengths may show more utility for the incorporation of CLs into composite scales.
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Fawad
authors.initials: F
authors.lastname: Yousuf
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Gloria
authors.initials: G
authors.lastname: Kim
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Shahamat
authors.initials: S
authors.lastname: Tauhid
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Partners Multiple Sclerosis Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Bonnie I
authors.initials: BI
authors.lastname: Glanz
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Renxin
authors.initials: R
authors.lastname: Chu
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Subhash
authors.initials: S
authors.lastname: Tummala
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Partners Multiple Sclerosis Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Healy
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Laboratory for Neuroimaging Research, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Partners Multiple Sclerosis Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Bakshi
keywords: MRI; brain; brain atrophy; cognition; cortical lesions; multiple sclerosis; physical disability; spinal cord