Quantitative assessment of brain iron by R(2)* relaxometry in patients with clinically isolated syndrome and relapsing-remitting multiple sclerosis

Mult Scler. 2009 Sep;15(9):1048-54. doi: 10.1177/1352458509106609. Epub 2009 Jun 25.

Abstract

Background: Increased iron deposition has been implicated in the pathophysiology of multiple sclerosis (MS), based on visual analysis of signal reduction on T(2)-weighted images. R(2)* relaxometry allows to assess brain iron accumulation quantitatively.

Objective: To investigate regional brain iron deposition in patients with a clinically isolated syndrome (CIS) or relapsing-remitting MS (RRMS) and its associations with demographical, clinical, and conventional magnetic resonance imaging (MRI) parameters.

Methods: We studied 69 patients (CIS, n = 32; RRMS, n = 37) with 3T MRI and analyzed regional R(2)* relaxation rates and their correlations with age, disease duration, disability, T(2) lesion load, and normalized brain volumes.

Results: Basal ganglia R(2)* relaxation rates increased in parallel with age (r = 0.3-0.6; P < 0.01) and were significantly higher in RRMS than in CIS (P < 0.05). Using multivariate linear regression analysis, the rate of putaminal iron deposition was independently predicted by the patients' age, disease duration, and gray matter atrophy.

Conclusions: Quantitative assessment by R(2)* relaxometry suggests increased iron deposition in the basal ganglia of MS patients, which is associated with disease duration and brain atrophy. This technique together with long-term follow-up thus appears suited to clarify whether regional iron accumulation contributes to MS morbidity or merely reflects an epiphenomenon.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Atrophy
  • Basal Ganglia / metabolism*
  • Basal Ganglia / pathology*
  • Brain Mapping / methods
  • Brain Stem / metabolism
  • Brain Stem / pathology
  • Demyelinating Diseases / metabolism
  • Demyelinating Diseases / pathology
  • Female
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Humans
  • Iron / metabolism*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Multiple Sclerosis, Relapsing-Remitting / metabolism*
  • Multiple Sclerosis, Relapsing-Remitting / pathology*
  • Thalamus / metabolism
  • Thalamus / pathology
  • Young Adult

Substances

  • Iron