title: Patterns of white matter atrophy in frontotemporal lobar degeneration.
abstract: BACKGROUND
  Structural magnetic resonance imaging (MRI) has been used to investigate the in vivo pathology of frontotemporal lobar degeneration. However, few neuroimaging studies have focused on white matter (WM) alterations in this disease.
  
  
  OBJECTIVE
  To use volumetric MRI techniques to identify the patterns of WM atrophy in vivo in 2 clinical variants of frontotemporal lobar degeneration-frontotemporal dementia (FTD) and semantic dementia-and to compare the patterns of WM atrophy with those of gray matter (GM) atrophy in these diseases.
  
  
  METHODS
  Structural MRIs were obtained from patients with FTD (n = 12) and semantic dementia (n = 13) and in cognitively healthy age-matched controls (n = 24). Regional GM and WM were classified automatically from high-resolution T1-, T2-, and proton density-weighted MRIs with Expectation-Maximization Segmentation and compared between the groups using a multivariate analysis of covariance model that included age and WM lesion volumes as covariates.
  
  
  RESULTS
  Patients with FTD had frontal WM atrophy and frontal, parietal, and temporal GM atrophy compared with controls, who had none. Patients with semantic dementia had temporal WM and GM atrophy and patients with FTD had frontal GM atrophy. Adding temporal WM volume to temporal GM volume significantly improved the discrimination between semantic dementia and FTD.
  
  
  CONCLUSIONS
  These results show that patients with frontotemporal lobar degeneration who are in relatively early stages of the disease (Clinical Dementia Rating score, 1.0-1.2) have WM atrophy that largely parallels the pattern of GM atrophy typically associated with these disorders.
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, San Francisco Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA. linda.chao@ucsf.edu
authors.forename: Linda L
authors.initials: LL
authors.lastname: Chao
authors.forename: Norbert
authors.initials: N
authors.lastname: Schuff
authors.forename: Erin M
authors.initials: EM
authors.lastname: Clevenger
authors.forename: Susanne G
authors.initials: SG
authors.lastname: Mueller
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Rosen
authors.forename: Maria L
authors.initials: ML
authors.lastname: Gorno-Tempini
authors.forename: Joel H
authors.initials: JH
authors.lastname: Kramer
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Miller
authors.forename: Michael W
authors.initials: MW
authors.lastname: Weiner
mesh_terms: D000368:Aged; D001284:Atrophy; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000473:pathology*; D003704:Dementia / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009457:Neuroglia / Q000473:pathology*; D013045:Species Specificity