title: Evolution of brain gray matter loss in Huntington's disease: a meta-analysis.
abstract: BACKGROUND
  Huntington's disease is characterized by neuronal loss throughout the disease course. Voxel-based morphometry studies have reported reductions in gray matter concentration (GMC) in many brain regions in patients with Huntington. The description of the time course of gray matter loss may help to identify some evolution markers. Here, we conducted a meta-analysis of voxel-based morphometry studies of Huntington's disease to describe the evolution of brain gray matter loss.
  
  
  METHODS
  A systematic search led to the inclusion of 11 articles on Huntington's disease (297 patients and 205 controls). We extracted data from patients with preclinical Huntington, patients with clinical Huntington, and controls. Finally, anatomical likelihood estimation analyses were conducted to identify GMC changes between preclinical patients and controls, between clinical patients and controls, and between preclinical and clinical patients.
  
  
  RESULTS
  Preclinical patients exhibited gray matter loss in the left basal ganglia and the prefrontal cortex. Clinical patients had bilateral gray matter loss in the basal ganglia, the prefrontal cortex, and the insula. The left striatum was smaller in clinical patients than in preclinical patients.
  
  
  CONCLUSIONS
  Neurodegenerative processes associated with Huntington's disease, as assessed by GMC reduction, begin in the left hemisphere and extend to the contralateral hemisphere throughout the inexorable course of the disease. Changes in gray matter, especially the volumetric side ratio of the striatum, could represent a relevant biomarker for characterizing the different progression stages of the disease.
authors.affiliation: Institut des Maladies Neurodégénératives, Centre National de la Recherche Scientifique UMR 5293, Université Victor Segalen Bordeaux 2, Bordeaux, France.
authors.forename: V
authors.initials: V
authors.lastname: Lambrecq
authors.forename: N
authors.initials: N
authors.lastname: Langbour
authors.forename: D
authors.initials: D
authors.lastname: Guehl
authors.forename: B
authors.initials: B
authors.lastname: Bioulac
authors.forename: P
authors.initials: P
authors.lastname: Burbaud
authors.forename: J-Y
authors.initials: JY
authors.lastname: Rotge
mesh_terms: D000328:Adult; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology*; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D007839:Functional Laterality; D006801:Humans; D006816:Huntington Disease / Q000175:diagnosis / Q000473:pathology*; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration / Q000473:pathology*; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology*