Increase in the iron content of the substantia nigra and red nucleus in multiple sclerosis and clinically isolated syndrome: a 7 Tesla MRI study.
OBJECTIVE
To study iron deposition in the substantia nigra (SN) and red nuclei (RN), in patients with clinically isolated syndrome (CIS) and relapsing remitting MS (RRMS) and healthy controls (HC).


METHODS
Iron deposition was assessed using susceptibility maps and T2*-w images acquired at high resolution MRI at 7 Tesla (T). Mean intensities were calculated within circular regions of interest in the SN (d/v, dorsal/ventral) and RN on high resolution T2*-w, quantitative susceptibility maps and their product for: RRMS, CIS and HC (N = 14, 21, 27, respectively).


RESULTS
Magnetic susceptibility was significantly greater in SNd and RN in RRMS compared with HC (P = 0.04 [0.001, 0.48] and P = 0.01 [0.005, 0.05]), with intermediate values for the CIS group. 1/T2*-w did not show significant inter-group differences (for SNv, SNd, RN, respectively: P = 0.5 [-0.352, 0976], P = 0.35 [-0.208, 0.778], P = 0.16 [-0.114, 0.885] for RRMS versus HC) and the T2*-susceptibility product maps showed the difference only for RN (P = 0.01, [0.009, 0.062]). Changes were independent of EDSS and disease duration.


CONCLUSIONS
MR changes consistent with iron accumulation occurring in the SN and RN of CIS patients can be identified using susceptibility mapping; this may provide an additional method of monitoring early MS development.
Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, United Kingdom.
Anna I
AI
Blazejewska
Ali M
AM
Al-Radaideh
Sam
S
Wharton
Su Yin
SY
Lim
Richard W
RW
Bowtell
Cris S
CS
Constantinescu
Penny A
PA
Gowland
D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D003711:Demyelinating Diseases / Q000378:metabolism*; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000378:metabolism* / Q000473:pathology; D012012:Red Nucleus / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013378:Substantia Nigra / Q000378:metabolism* / Q000473:pathology; D014018:Tissue Distribution; D015854:Up-Regulation
D015415:Biomarkers; D007501:Iron
clinically isolated syndrome; gray matter; magnetic resonance imaging; multiple sclerosis; red nucleus; substantia nigra