title: Quantitative assessment of the cervical spinal cord damage in neuromyelitis optica using diffusion tensor imaging at 3 Tesla.
abstract: OBJECTIVE
  To investigate whether quantitative MRI measures of cervical spinal cord white matter (WM) using diffusion tensor imaging (DTI) in neuromyelitis optica (NMO) differed from controls and correlated with clinical disability.
  
  
  METHODS
  Ten referred patients and 12 healthy volunteers were imaged on a 3 Tesla scanner and patients were clinically assessed on the Expanded Disability Status Scale (EDSS). Two raters quantified DTI-derived indices from all participants, including fractional anisotropy (FA), mean diffusivity (MD), parallel diffusivity (lambda[parallel]) and perpendicular diffusivity (lambda[perpendicular]) at C1-C6 for lateral and dorsal columns. After the inter-rater reliability test, univariate correlations between DTI measures and disability were assessed using the Spearman's rho correlation coefficient. Multiple regression analysis was performed to investigate which DTI measures independently correlated with the clinical score.
  
  
  RESULTS
  Statistical test results indicated high reliability of all DTI measurements between two raters. NMO patients showed reduced FA, increased MD and lambda[perpendicular] compared with controls while lambda[parallel] did not show any significant difference. The former three DTI metrics also showed significant correlations with disability scores, and especially FA was found to be sensitive to mild NMO (EDSS ≤ 3)
  
  
  CONCLUSIONS
  FA is a potentially useful quantitative biomarker of otherwise normal appearing WM damage in NMO. Such damage is associated with clinical disability.
authors: Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong.
authors: Wenshu
authors: W
authors: Qian
authors: Queenie
authors: Q
authors: Chan
authors: Henry
authors: H
authors: Mak
authors: Zhongping
authors: Z
authors: Zhang
authors: Marina-Portia
authors: MP
authors: Anthony
authors: Kelvin Kai-Wing
authors: KK
authors: Yau
authors: Pek-Lan
authors: PL
authors: Khong
authors: Koon Ho
authors: KH
authors: Chan
authors: Mina
authors: M
authors: Kim