title: Longitudinal features of STIR bright signal in FSHD.
abstract: BACKGROUND
  Magnetic resonance imaging of muscle shows short tau-inversion recovery (STIR) brightness in autosomal dominant facioscapulohumeral muscular dystrophy (FSHD1) suggestive of active inflammation/injury. We measured the longitudinal stability/progression of this potential disease biomarker.
  
  
  METHODS
  Nine subjects underwent calf MRI imaging over 2 years. Two radiologists evaluated qualitative muscle changes.
  
  
  RESULTS
  In 3/9 subjects, calf muscles demonstrated moderate/severe STIR hyperintensity at Time 1 that had progressed to fatty replacement 2 years later (Time 2). In the remaining subjects, moderate/severe muscle STIR abnormalities, when present, were consistent between exams. Mild STIR+ elevations had roughly similar patterns between exams.
  
  
  CONCLUSIONS
  Moderate/severe STIR hyperintensities often foreshadow fatty replacement over a 2-year interval. Whether longer time courses are required to observe muscle degeneration and fatty replacement in some subjects remains to be explored.
authors.forename: Seth D
authors.initials: SD
authors.lastname: Friedman
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Poliachik
authors.forename: Randolph K
authors.initials: RK
authors.lastname: Otto
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Carter
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Budech
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Bird
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Miller
authors.forename: Dennis W W
authors.initials: DW
authors.lastname: Shaw
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020391:Muscular Dystrophy, Facioscapulohumeral / Q000175:diagnosis*