title: Evaluation of deep gray matter volume, cortical thickness and white matter integrity in patients with typical absence epilepsy: a study using voxelwise-based techniques.
abstract: BACKGROUND
  The objective of this study was to evaluate the cortical thickness and the volume of deep gray matter structures, measured from 3D T1-weighted gradient echo imaging, and white matter integrity, by diffusion tensor imaging (DTI) in patients with typical absence epilepsy (AE).
  
  
  METHODS
  Patients (n = 19) with typical childhood AE and juvenile AE, currently taking antiepileptic medication, were compared with control subjects (n = 19), matched for gender and age. 3D T1 magnetization-prepared rapid gradient echo-weighted imaging and DTI along 30 noncolinear directions were performed using a 1.5-T MR scanner. FreeSurfer was used to perform cortical volumetric reconstruction and segmentation of deep gray matter structures. For tract-based spatial statistics analysis of DTI, a white matter skeleton was created, along with a permutation-based inference with 5000 permutations. A threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The mean, radial, and axial diffusivities were also projected onto the mean FA skeleton.
  
  
  RESULTS
  Patients with AE presented decreased FA and increased mean diffusivity and radial diffusivity values in the genu and the body of the corpus callosum and right anterior corona radiata, as well as decreased axial diffusivity in the left posterior thalamic radiation, inferior cerebellar peduncle, right cerebral peduncle, and right corticospinal tract. However, there were no significant differences in cortical thickness or deep gray matter structure volumes between patients with AE and controls.
  
  
  CONCLUSIONS
  Abnormalities found in white matter integrity may help to better understand the pathophysiology of AE and optimize diagnosis and treatment strategies.
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil. diogogoulartcorrea@yahoo.com.br.|Clínica de Diagnóstico por Imagem (CDPI), Rio de Janeiro, Brazil. diogogoulartcorrea@yahoo.com.br.
authors.forename: D G
authors.initials: DG
authors.lastname: Corrêa
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.|Clínica de Diagnóstico por Imagem (CDPI), Rio de Janeiro, Brazil.
authors.forename: N
authors.initials: N
authors.lastname: Ventura
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.|Department of Psychology, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: N
authors.initials: N
authors.lastname: Zimmermann
authors.affiliation: Clínica de Diagnóstico por Imagem (CDPI), Rio de Janeiro, Brazil.
authors.forename: T M
authors.initials: TM
authors.lastname: Doring
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.|Clínica de Diagnóstico por Imagem (CDPI), Rio de Janeiro, Brazil.
authors.forename: G
authors.initials: G
authors.lastname: Tukamoto
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.
authors.forename: J
authors.initials: J
authors.lastname: Leme
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Pereira
authors.affiliation: Department of Neurology, Epilepsy Center, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: I
authors.initials: I
authors.lastname: D'Andrea
authors.affiliation: Department of Neurology, Epilepsy Center, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: C
authors.initials: C
authors.lastname: Rêgo
authors.affiliation: Department of Neurology, Epilepsy Center, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: S V
authors.initials: SV
authors.lastname: Alves-Leon
authors.affiliation: Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rua Rodolpho Paulo Rocco 255, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, 21941-913, Brazil.|Clínica de Diagnóstico por Imagem (CDPI), Rio de Janeiro, Brazil.
authors.forename: E L
authors.initials: EL
authors.lastname: Gasparetto
mesh_terms: D016880:Anisotropy; D003430:Cross-Sectional Studies; D056324:Diffusion Tensor Imaging / Q000379:methods*; D004832:Epilepsy, Absence / Q000473:pathology*; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D066127:White Matter / Q000473:pathology*; D055815:Young Adult
keywords: Absence epilepsy; Cortical thickness; Diffusion tensor imaging; Magnetic resonance imaging