title: Fractional anisotropy in three variants of primary progressive aphasia.
abstract: OBJECTIVE
  Our aim was to report diffusion tensor imaging (DTI) patterns in three patients, each with a different primary progressive aphasia (PPA) variant.
  
  
  METHODS
  One agrammatic PPA, one semantic PPA, and one logopenic PPA subject underwent a magnetic resonance imaging examination including DTI sequences. The fractional anisotropy (FA) value was calculated in regions of interest (ROIs) involved in these three variants (perisylvian region, temporal pole, and parietotemporal junction) for each patient. Left-right FA ratios in each ROI were compared between PPA subjects and a group of three amnestic mild cognitive impairment patients with a cerebrospinal fluid biomarker profile of the Alzheimer type.
  
  
  RESULTS
  The FA values were lower in the left hemisphere (p=0.03). The lowest FA values were observed in the left perisylvian region for the non-fluent/agrammatic subtype PPA patient, in the left anterior temporal lobe for the semantic subtype PPA patient, and in the left parietotemporal junction for the logopenic patient (p=0.028). The left-right FA ratio in these specific ROIs for each PPA variant was significantly lower than in the amnestic mild cognitive impairment group (p=0.009).
  
  
  CONCLUSIONS
  DTI patterns could be an effective new tool for diagnosing PPA and classifying the three variants.
authors.affiliation: Memory Center of Research and Resources (CMRR), Department of Neurology, INSERM CIT 808, University Hospital of Besançon, and EA 481 Neuroscience, IFR 133, University of Franche-Comte, Besançon, France. eloi.magnin@laposte.net
authors.forename: Eloi
authors.initials: E
authors.lastname: Magnin
authors.forename: Françoise
authors.initials: F
authors.lastname: Cattin
authors.forename: Pierre
authors.initials: P
authors.lastname: Vandel
authors.forename: Jean
authors.initials: J
authors.lastname: Galmiche
authors.forename: Thierry
authors.initials: T
authors.lastname: Moulin
authors.forename: Lucien
authors.initials: L
authors.lastname: Rumbach
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016880:Anisotropy; D018888:Aphasia, Primary Progressive / Q000175:diagnosis* / Q000503:physiopathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male