title: High-level gait disorder: associations with specific white matter changes observed on advanced diffusion imaging.
abstract: OBJECTIVE
  High-level gait disorder (HLGD) is a debilitating disorder causing mobility decline in the elderly. Although its clinical characteristics are well described, its anatomical and pathophysiological underpinnings are poorly understood. This study examined the anatomical distribution of white matter (WM) changes in patients with mild to moderate HLGD of the cautious/disequilibrium type, using advanced magnetic resonance imaging (MRI) methods.
  
  
  METHODS
  Thirteen patients with HLGD, 9 elderly and 13 middle-aged healthy controls were scanned using diffusion tensor imaging, Q-space imaging, and conventional MRI. The regions of significant differences between the HLGD group and the elderly control group were defined, and the mean fractional anisotropy and displacement values of these areas were extracted.
  
  
  RESULTS
  The HLGD patients had lower fractional anisotropy and higher displacement values in regions related to the motor system, including those along the corticospinal tract and the superior cerebellar peduncles, as well as in cognitive and affective-related areas, including the anterior limbs of the internal capsule and the genu of the corpus callosum.
  
  
  CONCLUSIONS
  The anatomical distribution associated with HLGD of the cautious/disequilibrium type involves WM pathways that convey motor-related, cognitive and affective-related functions. The underlying pathological process leading to these changes most probably includes demyelination.
authors.affiliation: Functional Brain Center, Wohl Institute for Advanced Imaging, Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Kafri
authors.forename: Efrat
authors.initials: E
authors.lastname: Sasson
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Assaf
authors.forename: Yaacov
authors.initials: Y
authors.lastname: Balash
authors.forename: Orna
authors.initials: O
authors.lastname: Aiznstein
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Hausdorff
authors.forename: Nir
authors.initials: N
authors.lastname: Giladi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001921:Brain / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D020233:Gait Disorders, Neurologic / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity