title: Characteristics of lesional and extra-lesional cortical grey matter in relapsing-remitting and secondary progressive multiple sclerosis: A magnetisation transfer and diffusion tensor imaging study.
abstract: BACKGROUND
  In multiple sclerosis (MS), diffusion tensor and magnetisation transfer imaging are both abnormal in lesional and extra-lesional cortical grey matter, but differences between clinical subtypes and associations with clinical outcomes have only been partly assessed.
  
  
  OBJECTIVE
  To compare mean diffusivity, fractional anisotropy and magnetisation transfer ratio (MTR) in cortical grey matter lesions (detected using phase-sensitive inversion recovery (PSIR) imaging) and extra-lesional cortical grey matter, and assess associations with disability in relapse-onset MS.
  
  
  METHODS
  Seventy-two people with MS (46 relapsing-remitting (RR), 26 secondary progressive (SP)) and 36 healthy controls were included in this study. MTR, mean diffusivity and fractional anisotropy were measured in lesional and extra-lesional cortical grey matter.
  
  
  RESULTS
  Mean fractional anisotropy was higher and MTR lower in lesional compared with extra-lesional cortical grey matter. In extra-lesional cortical grey matter mean fractional anisotropy and MTR were lower, and mean diffusivity was higher in the MS group compared with controls. Mean MTR was lower and mean diffusivity was higher in lesional and extra-lesional cortical grey matter in SPMS when compared with RRMS. These differences were independent of disease duration. In multivariate analyses, MTR in extra-lesional more so than lesional cortical grey matter was associated with disability.
  
  
  CONCLUSIONS
  Magnetic resonance abnormalities in lesional and extra-lesional cortical grey matter are greater in SPMS than RRMS. Changes in extra-lesional compared with lesional cortical grey matter are more consistently associated with disability.
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/MS Center, University Hospital Basel, Switzerland o.yaldizli@ucl.ac.uk.
authors.forename: Özgür
authors.initials: Ö
authors.lastname: Yaldizli
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Pardini
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK.
authors.forename: Varun
authors.initials: V
authors.lastname: Sethi
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/School of Psychology and Cardiff University Brain Research Imaging Centre, Cardiff University, UK.
authors.forename: Nils
authors.initials: N
authors.lastname: Muhlert
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/Department of Neurology, Xuanwu Hospital of Capital Medical University, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Tozer
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Samson
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK.
authors.forename: Claudia Am
authors.initials: CA
authors.lastname: Wheeler-Kingshott
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/National Institute for Health Research (NIHR), University College London Hospitals (UCLH) Biomedical Research Centre, UK/Brain Repair and Rehabilitation, UCL Institute of Neurology, UK/Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, UK.
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Yousry
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/National Institute for Health Research (NIHR), University College London Hospitals (UCLH) Biomedical Research Centre, UK.
authors.forename: David H
authors.initials: DH
authors.lastname: Miller
authors.affiliation: Queen Square MS Centre, UCL Institute of Neurology, UK/National Institute for Health Research (NIHR), University College London Hospitals (UCLH) Biomedical Research Centre, UK.
authors.forename: Declan T
authors.initials: DT
authors.lastname: Chard
mesh_terms: D000328:Adult; D016880:Anisotropy; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000473:pathology* / Q000503:physiopathology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology* / Q000503:physiopathology; D012008:Recurrence
keywords: MRI; Multiple sclerosis; diffusion tensor imaging; grey matter lesions; magnetisation transfer imaging; normal-appearing grey matter