title: Structural changes of central white matter tracts in Kennedy's disease - a diffusion tensor imaging and voxel-based morphometry study.
abstract: OBJECTIVE
  Spinobulbar muscular atrophy [Kennedy's disease (KD)] is a rare X-linked neurodegenerative disorder of mainly spinal and bulbar motoneurons. Recent studies suggest a multisystem character of this disease. The aim of this study was to identify and characterize structural changes of gray (GM) and white matter (WM) in the central nervous system.
  
  
  METHODS
  Whole-brain-based voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) analyses were applied to MRI data of eight genetically proven patients with KD and compared with 16 healthy age-matched controls.
  
  
  RESULTS
  Diffusion tensor imaging analysis showed not only decreased fractional anisotropy (FA) values in the brainstem, but also widespread changes in central WM tracts, whereas VBM analysis of the WM showed alterations primarily in the brainstem and cerebellum. There were no changes in GM volume. The FA value decrease in the brainstem correlated with the disease duration.
  
  
  CONCLUSIONS
  Diffusion tensor imaging analysis revealed subtle changes of central WM tract integrity, while GM and WM volume remained unaffected. In our patient sample, KD had more extended effects than previously reported. These changes could either be attributed primarily to neurodegeneration or reflect secondary plastic changes due to atrophy of lower motor neurons and reorganization of cortical structures.
authors.affiliation: Department of Radiology, University of Muenster, Germany.
authors.forename: C C
authors.initials: CC
authors.lastname: Pieper
authors.forename: C
authors.initials: C
authors.lastname: Konrad
authors.forename: J
authors.initials: J
authors.lastname: Sommer
authors.forename: I
authors.initials: I
authors.lastname: Teismann
authors.forename: H
authors.initials: H
authors.lastname: Schiffbauer
mesh_terms: D000328:Adult; D000368:Aged; D016880:Anisotropy; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D001933:Brain Stem / Q000473:pathology; D055534:Bulbo-Spinal Atrophy, X-Linked / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology; D002540:Cerebral Cortex / Q000473:pathology; D056324:Diffusion Tensor Imaging; D005207:Fasciculation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration; D009413:Nerve Fibers, Myelinated / Q000473:pathology*