Quantitative high-field imaging of sub-cortical gray matter in multiple sclerosis.
BACKGROUND
In addition to neuronal injury, inflammatory, and demyelinating processes, evidence suggests multiple sclerosis (MS) is also associated with increased iron deposition in the basal ganglia. Magnetic resonance imaging (MRI), particularly at very high field strengths, is sensitive to iron accumulation and may enable visualization and quantification of iron associated with MS.


OBJECTIVE
To investigate the sub-cortical gray matter in patients with early-stage relapsing-remitting MS using multiple, and novel, quantitative MRI measures at very high field.


METHODS
In total, 22 patients with relapsing-remitting MS and 22 control subjects were imaged at 4.7 Tesla. Transverse relaxation rates (R₂ and R₂*) and susceptibility phase were quantified in four basal ganglia nuclei, the thalamus, and the red nuclei. Parameters in patients with MS were compared with those in healthy subjects and correlated with clinical scores.


RESULTS
Significant abnormalities were observed in most structures, most notably in the pulvinar sub-nucleus. Significant correlations with disability were observed in the pulvinar; marginally significant correlations were also observed in the thalamus and red nucleus. No significant correlations were observed with duration since index relapse.


CONCLUSIONS
Widespread abnormalities are present in the deep gray matter nuclei of patients recently diagnosed with MS; these abnormalities can be detected via multi-modal high-field MRI. Imaging metrics, particularly R₂*, relate to disease severity in the pulvinar and other gray matter regions.
Department of Biomedical Engineering, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. mlebel@gmail.com
R Marc
RM
Lebel
Amir
A
Eissa
Peter
P
Seres
Gregg
G
Blevins
Alan H
AH
Wilman
D000328:Adult; D001479:Basal Ganglia / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007501:Iron / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000378:metabolism / Q000473:pathology*; D012012:Red Nucleus / Q000378:metabolism / Q000473:pathology; D013788:Thalamus / Q000378:metabolism / Q000473:pathology
D007501:Iron