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

• Published in: Multiple sclerosis Vol. 15; no. 9; pp. 1048 - 1054
• Main Authors: Khalil, M, Enzinger, C, Langkammer, C, Tscherner, M, Wallner-Blazek, M, Jehna, M, Ropele, S, Fuchs, S, Fazekas, F
• Format: Journal Article
• Language: English
• Published: England 01.09.2009
• Subjects: 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
• ISSN: 1352-4585
• DOI: 10.1177/1352458509106609

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. 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. 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. 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. 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.