title: 7 Tesla magnetic resonance imaging to detect cortical pathology in multiple sclerosis.
abstract: BACKGROUND
  Neocortical lesions (NLs) are an important pathological component of multiple sclerosis (MS), but their visualization by magnetic resonance imaging (MRI) remains challenging.
  
  
  OBJECTIVE
  We aimed at assessing the sensitivity of multi echo gradient echo (ME-GRE) T2*-weighted MRI at 7.0 Tesla in depicting NLs compared to myelin and iron staining.
  
  
  METHODS
  Samples from two MS patients were imaged post mortem using a whole body 7 T MRI scanner with a 24-channel receive-only array. Isotropic 200 micron resolution images with varying T2* weighting were reconstructed from the ME-GRE data and converted into R2* maps. Immunohistochemical staining for myelin (proteolipid protein, PLP) and diaminobenzidine-enhanced Turnbull blue staining for iron were performed.
  
  
  RESULTS
  Prospective and retrospective sensitivities of MRI for the detection of NLs were 48% and 67% respectively. We observed MRI maps detecting only a small portion of 20 subpial NLs extending over large cortical areas on PLP stainings. No MRI signal changes suggestive of iron accumulation in NLs were observed. Conversely, R2* maps indicated iron loss in NLs, which was confirmed by histological quantification.
  
  
  CONCLUSIONS
  High-resolution post mortem imaging using R2* and magnitude maps permits detection of focal NLs. However, disclosing extensive subpial demyelination with MRI remains challenging.
authors.affiliation: Advanced Magnetic Resonance Imaging Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America; Center for Neuroimaging Research, Kessler Foundation, West Orange, New Jersey, United States of America.
authors.forename: Bing
authors.initials: B
authors.lastname: Yao
authors.affiliation: Center for Brain Research, Medical University, Vienna, Austria.
authors.forename: Simon
authors.initials: S
authors.lastname: Hametner
authors.affiliation: Advanced Magnetic Resonance Imaging Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America.
authors.forename: Peter
authors.initials: P
authors.lastname: van Gelderen
authors.affiliation: Advanced Magnetic Resonance Imaging Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America.
authors.forename: Hellmuth
authors.initials: H
authors.lastname: Merkle
authors.affiliation: Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America.
authors.forename: Christina
authors.initials: C
authors.lastname: Chen
authors.affiliation: Center for Brain Research, Medical University, Vienna, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Lassmann
authors.affiliation: Advanced Magnetic Resonance Imaging Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America.
authors.forename: Jeff H
authors.initials: JH
authors.lastname: Duyn
authors.affiliation: Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, United States of America; Department of Radiology and Radiological Science, Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Francesca
authors.initials: F
authors.lastname: Bagnato
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D019579:Neocortex / Q000473:pathology*; D011446:Prospective Studies; D012189:Retrospective Studies