Untangling the R2* contrast in multiple sclerosis: A combined MRI-histology study at 7.0 Tesla

PLoS One. 2018 Mar 21;13(3):e0193839. doi: 10.1371/journal.pone.0193839. eCollection 2018.

Abstract

T2*-weighted multi-echo gradient-echo magnetic resonance imaging and its reciprocal R2* are used in brain imaging due to their sensitivity to iron content. In patients with multiple sclerosis who display pathological alterations in iron and myelin contents, the use of R2* may offer a unique way to untangle mechanisms of disease. Coronal slices from 8 brains of deceased multiple sclerosis patients were imaged using a whole-body 7.0 Tesla MRI scanner. The scanning protocol included three-dimensional (3D) T2*-w multi-echo gradient-echo and 2D T2-w turbo spin echo (TSE) sequences. Histopathological analyses of myelin and iron content were done using Luxol fast blue and proteolipid myelin staining and 3,3'-diaminobenzidine tetrahydrochloride enhanced Turnbull blue staining. Quantification of R2*, myelin and iron intensity were obtained. Variations in R2* were found to be affected differently by myelin and iron content in different regions of multiple sclerosis brains. The data shall inform clinical investigators in addressing the role of T2*/R2* variations as a biomarker of tissue integrity in brains of MS patients, in vivo.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Brain / diagnostic imaging*
  • Brain / metabolism
  • Brain / pathology*
  • Contrast Media
  • Female
  • Humans
  • Imaging, Three-Dimensional
  • Immunohistochemistry
  • Iron / metabolism
  • Magnetic Resonance Imaging* / instrumentation
  • Magnetic Resonance Imaging* / methods
  • Male
  • Middle Aged
  • Multiple Sclerosis, Chronic Progressive / diagnostic imaging*
  • Multiple Sclerosis, Chronic Progressive / metabolism
  • Multiple Sclerosis, Chronic Progressive / pathology*
  • Myelin Sheath / metabolism

Substances

  • Contrast Media
  • Iron