title: Diffusion tensor imaging in multiple sclerosis: assessment of regional differences in the axial plane within normal-appearing cervical spinal cord.
abstract: OBJECTIVE
  Evaluation of the spinal cord is important in the diagnosis and follow-up of patients with multiple sclerosis. Our purpose was to investigate diffusion tensor imaging (DTI) changes in different regions of normal-appearing spinal cord (NASC) in relapsing-remitting multiple sclerosis (RRMS).
  
  
  METHODS
  Axial DTI of the cervical spinal cord was performed in 24 patients with RRMS and 24 age- and sex-matched control subjects. Fractional anisotropy (FA) and mean diffusivity (MD) were calculated in separate regions of interest (ROIs) in the anterior, lateral, and posterior spinal cord, bilaterally, and the central spinal cord, at the C2-C3 level. Patients and control subjects were compared with respect to FA and MD with the use of an exact Mann-Whitney test. Logistic regression and receiver operating characteristic (ROC) curve analysis assessed the utility of each measure for the diagnosis of RRMS.
  
  
  RESULTS
  DTI metrics in areas of NASC in MS were significantly different in patients compared with control subjects; FA was lower in the lateral (mean +/- SD of 0.56 +/- 0.10 versus 0.69 +/- 0.09 in control subjects, P < .0001), posterior (0.52 +/- 0.11 versus 0.63 +/- 0.10, P < .0001), and central (0.53 +/- 0.10 versus 0.58 +/- 0.10, P = .049) NASC ROIs. Assessing DTI metrics in the diagnosis of MS, a sensitivity of 87.0% (95% confidence interval [CI], 66.4 to 97.1) and a specificity of 91.7% (95% CI, 73.0 to 98.7) were demonstrated.
  
  
  CONCLUSIONS
  The NASC in RRMS demonstrates DTI changes. This may prove useful in detecting occult spinal cord pathology, predicting clinical course, and monitoring disease progression and therapeutic effect in MS.
authors.affiliation: Department of Radiology, New York University Medical Center, 530 First Avenue, New York, NY 10016, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Hesseltine
authors.forename: M
authors.initials: M
authors.lastname: Law
authors.forename: J
authors.initials: J
authors.lastname: Babb
authors.forename: M
authors.initials: M
authors.lastname: Rad
authors.forename: S
authors.initials: S
authors.lastname: Lopez
authors.forename: Y
authors.initials: Y
authors.lastname: Ge
authors.forename: G
authors.initials: G
authors.lastname: Johnson
authors.forename: R I
authors.initials: RI
authors.lastname: Grossman
mesh_terms: D000328:Adult; D000368:Aged; D016880:Anisotropy; D002574:Cervical Vertebrae; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology*; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000473:pathology*