title: Corpus callosum atrophy correlates with gray matter atrophy in patients with multiple sclerosis.
abstract: OBJECTIVE
  Atrophy of the corpus callosum is a recognized characteristic of multiple sclerosis (MS). We describe a new reliable method for measuring corpus callosum atrophy and correlate this with global cerebral atrophy measures.
  
  
  METHODS
  Whole brain 3T MRI was performed in 38 relapsing-remitting MS subjects and 21 healthy controls (HC). Brain global gray and white matter volumes were segmented with SPM8. The contour of the corpus callosum was outlined on the midline of 3-D T1-weighted images by a semiautomated edge-detection technique to determine the corpus callosum area (CCA). Normalized CCA was correlated with other brain atrophy measures in MS subjects.
  
  
  RESULTS
  CCA was disproportionately lower in MS subjects vs. HC (20.1% mean decrease; P < .001), with a large effect size (d = .62) when compared with global atrophy measures. In MS subjects, CCA correlated with brain parenchymal fraction (r = .55; P < .001) and gray matter fraction (r = .45; P = .005) but not white matter fraction (r = .18; P = .29). An inverse correlation with FLAIR hyperintense lesion volume (r = -.40; P = .01) was detected for CCA.
  
  
  CONCLUSIONS
  Measurement of atrophy of the corpus callosum can have sensitivity as a useful imaging biomarker in patients with MS, even in patients with low disability levels. Both gray and white matter involvement in MS contribute to corpus callosum atrophy.
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Klawiter
authors.forename: Antonia
authors.initials: A
authors.lastname: Ceccarelli
authors.forename: Ashish
authors.initials: A
authors.lastname: Arora
authors.forename: Jonathan
authors.initials: J
authors.lastname: Jackson
authors.forename: Sonya
authors.initials: S
authors.lastname: Bakshi
authors.forename: Gloria
authors.initials: G
authors.lastname: Kim
authors.forename: Jennifer
authors.initials: J
authors.lastname: Miller
authors.forename: Shahamat
authors.initials: S
authors.lastname: Tauhid
authors.forename: Christian
authors.initials: C
authors.lastname: von Gizycki
authors.forename: Rohit
authors.initials: R
authors.lastname: Bakshi
authors.forename: Mohit
authors.initials: M
authors.lastname: Neema
mesh_terms: D000328:Adult; D061085:Agenesis of Corpus Callosum / Q000150:complications* / Q000473:pathology*; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009103:Multiple Sclerosis / Q000150:complications* / Q000473:pathology*; D010363:Pattern Recognition, Automated / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D066127:White Matter / Q000473:pathology
keywords: Multiple sclerosis; atrophy; corpus callosum