title: Asymptomatic carotid stenosis is associated with gray and white matter damage.
abstract: BACKGROUND
  Cognitive deficits in patients with asymptomatic carotid stenosis have been reported. The ultimate mechanism of cognitive deficits remains unclear and might be related to subtle structural brain damage.
  
  
  OBJECTIVE
  The aim of the present study was to evaluate the presence of subtle white and grey matter abnormalities associated with asymptomatic carotid stenosis.
  
  
  METHODS
  Twenty-five patients with asymptomatic ≥70%/occlusion carotid stenosis and 25 healthy controls, matched for gender and age, underwent 3 Tesla brain magnetic resonance imaging. Gray and white matter macrostructural abnormalities were evaluated with voxel-based morphometry using spm8 software. White matter microstructural abnormalities were evaluated with diffusion tensor images with the Diffusion Toolbox package and tract-based spatial statistics from FMRIB Software Library.
  
  
  RESULTS
  We observed significant macro- and microstructural white matter abnormalities, and these findings were diffuse and symmetrical in both hemispheres. In contrast, gray matter atrophy was observed in the areas corresponding to the anterior circulation of the hemisphere ipsilateral to the carotid stenosis.
  
  
  CONCLUSIONS
  Patients with asymptomatic carotid stenosis have different patterns of gray and white matter abnormalities. While the white matter damage is diffuse, the gray matter atrophy is localized in the territory of anterior circulation ipsilateral to the stenosis. The role of asymptomatic carotid stenosis in the gray matter damage must be further investigated with longitudinal studies and comparison with neuropsychological evaluation.
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Wagner M
authors.initials: WM
authors.lastname: Avelar
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Anelyssa
authors.initials: A
authors.lastname: D'Abreu
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Coan
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Fabrício Oliveira
authors.initials: FO
authors.lastname: Lima
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Rachel
authors.initials: R
authors.lastname: Guimarães
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Clarissa L
authors.initials: CL
authors.lastname: Yassuda
authors.affiliation: Department of Surgery, University of Campinas, Campinas, SP, Brazil.
authors.forename: Germano P
authors.initials: GP
authors.lastname: Oliveira
authors.affiliation: Department of Surgery, University of Campinas, Campinas, SP, Brazil.
authors.forename: Ana T
authors.initials: AT
authors.lastname: Guillaumon
authors.affiliation: Department of Radiology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Augusto A
authors.initials: AA
authors.lastname: Filho
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Li L
authors.initials: LL
authors.lastname: Min
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, SP, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: Cendes
mesh_terms: D000368:Aged; D001284:Atrophy / Q000150:complications / Q000473:pathology; D001921:Brain / Q000473:pathology*; D016893:Carotid Stenosis / Q000150:complications* / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012984:Software; D066127:White Matter / Q000473:pathology*
keywords: DTI; MRI; brain atrophy; carotid stenosis; voxel based morphometry