title: Quantification of global cerebral atrophy in multiple sclerosis from 3T MRI using SPM: the role of misclassification errors.
abstract: OBJECTIVE
  We tested the validity of a freely available segmentation pipeline to measure compartmental brain volumes from 3T MRI in patients with multiple sclerosis (MS). Our primary focus was methodological to explore the effect of segmentation corrections on the clinical relevance of the output metrics.
  
  
  METHODS
  Three-dimensional T1-weighted images were acquired to compare 61 MS patients to 30 age- and gender-matched normal controls (NC). We also tested the within patient MRI relationship to disability (eg, expanded disability status scale [EDSS] score) and cognition. Statistical parametric mapping v. 8 (SPM8)-derived gray matter (GMF), white matter (WMF), and total brain parenchyma fractions (BPF) were derived before and after correcting errors from T1 hypointense MS lesions and/or ineffective deep GM contouring.
  
  
  RESULTS
  MS patients had lower GMF and BPF as compared to NC (P<.05). Cognitively impaired patients had lower BPF than cognitively preserved patients (P<.05). BPF was related to EDSS; BPF and GMF were related to disease duration (all P<.05). Errors caused bias in GMFs and WMFs but had no discernable influence on BPFs or any MRI-clinical associations.
  
  
  CONCLUSIONS
  We report the validity of a segmentation pipeline for the detection of MS-related brain atrophy with 3T MRI. Longitudinal studies are warranted to extend these results.
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Elisa
authors.initials: E
authors.lastname: Dell'Oglio
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Antonia
authors.initials: A
authors.lastname: Ceccarelli
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Bonnie I
authors.initials: BI
authors.lastname: Glanz
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Healy
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Shahamat
authors.initials: S
authors.lastname: Tauhid
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Ashish
authors.initials: A
authors.lastname: Arora
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Nikila
authors.initials: N
authors.lastname: Saravanan
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Bruha
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Vartanian
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Sheena L
authors.initials: SL
authors.lastname: Dupuy
authors.affiliation: Department of Neurology, State University of New York, Buffalo, NY.
authors.forename: Ralph H B
authors.initials: RHB
authors.lastname: Benedict
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Bakshi
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Laboratory for Neuroimaging Research, Partners MS Center, Harvard Medical School, Boston, MA.
authors.forename: Mohit
authors.initials: M
authors.lastname: Neema
mesh_terms: D000328:Adult; D000465:Algorithms; D016477:Artifacts; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009103:Multiple Sclerosis / Q000473:pathology*; D010363:Pattern Recognition, Automated / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Brain atrophy; MRI; gray matter; lesions; multiple sclerosis; segmentation