title: Patterns of brain atrophy in clinical variants of frontotemporal lobar degeneration.
abstract: OBJECTIVE
  The clinical syndromes of frontotemporal lobar degeneration include behavioral variant frontotemporal dementia (bvFTD) and semantic (SV-PPA) and nonfluent variants (NF-PPA) of primary progressive aphasia. Using magnetic resonance imaging (MRI), tensor-based morphometry (TBM) was used to determine distinct patterns of atrophy between these three clinical groups.
  
  
  METHODS
  Twenty-seven participants diagnosed with bvFTD, 16 with SV-PPA, and 19 with NF-PPA received baseline and follow-up MRI scans approximately 1 year apart. TBM was used to create three-dimensional Jacobian maps of local brain atrophy rates for individual subjects.
  
  
  RESULTS
  Regional analyses were performed on the three-dimensional maps and direct comparisons between groups (corrected for multiple comparisons using permutation tests) revealed significantly greater frontal lobe and frontal white matter atrophy in the bvFTD relative to the SV-PPA group (p < 0.005). The SV-PPA subjects exhibited significantly greater atrophy than the bvFTD in the fusiform gyrus (p = 0.007). The NF-PPA group showed significantly more atrophy in the parietal lobes relative to both bvFTD and SV-PPA groups (p < 0.05). Percent volume change in ventromedial prefrontal cortex was significantly associated with baseline behavioral symptomatology.
  
  
  CONCLUSIONS
  The bvFTD, SV-PPA, and NF-PPA groups displayed distinct patterns of progressive atrophy over a 1-year period that correspond well to the behavioral disturbances characteristic of the clinical syndromes. More specifically, the bvFTD group showed significant white matter contraction and presence of behavioral symptoms at baseline predicted significant volume loss of the ventromedial prefrontal cortex.
authors.affiliation: Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA. plu@mednet.ucla.edu
authors.forename: Po H
authors.initials: PH
authors.lastname: Lu
authors.forename: Mario F
authors.initials: MF
authors.lastname: Mendez
authors.forename: Grace J
authors.initials: GJ
authors.lastname: Lee
authors.forename: Alex D
authors.initials: AD
authors.lastname: Leow
authors.forename: Hyun-Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Jill
authors.initials: J
authors.lastname: Shapira
authors.forename: Elvira
authors.initials: E
authors.lastname: Jimenez
authors.forename: Bradley B
authors.initials: BB
authors.lastname: Boeve
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Caselli
authors.forename: Neill R
authors.initials: NR
authors.lastname: Graff-Radford
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Jack
authors.forename: Joel H
authors.initials: JH
authors.lastname: Kramer
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Miller
authors.forename: George
authors.initials: G
authors.lastname: Bartzokis
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
authors.forename: David S
authors.initials: DS
authors.lastname: Knopman
mesh_terms: D000368:Aged; D000465:Algorithms; D001284:Atrophy; D001519:Behavior / Q000502:physiology; D001921:Brain / Q000473:pathology*; D003071:Cognition / Q000502:physiology; D056324:Diffusion Tensor Imaging; D018450:Disease Progression; D056344:Executive Function; D005260:Female; D057174:Frontotemporal Lobar Degeneration / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007802:Language; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology