Background: Deep gray matter (DGM) is affected in relapsing-remitting multiple sclerosis (RRMS) and may be studied using short-term longitudinal MRI.
Objective: To investigate two-year changes in spin-echo transverse relaxation rate (R2) and atrophy in DGM, and its relationship with disease severity in RRMS patients.
Methods: Twenty six RRMS patients and 26 matched controls were imaged at 4.7 T. Multiecho spin-echo R2 maps and atrophy measurements were obtained in DGM at baseline and two-year follow-up. Differences between MRI measures and correlations to disease severity were examined.
Results: After two years, mean R2 values in the globus pallidus and pulvinar increased by ~4% (p<0.001) in patients and <1.7% in controls. Two-year changes in R2 showed significant correlation to disease severity in the globus pallidus, pulvinar, substantia nigra, and thalamus. Multiple regression of the two-year R2 difference using these four DGM structures as variables, yielded high correlation with disease severity (r=0.83, p<0.001). Two-year changes in volume and R2 showed significant correlation only for the globus pallidus in multiple sclerosis (MS) (p<0.05).
Conclusions: Two-year difference R2 measurements in DGM correlate to disease severity in MS. R2 mapping and atrophy measurements over two years can be used to identify changes in DGM in MS.
Keywords: MS Severity Score; Multiple sclerosis; R2; atrophy; brain volume; deep gray matter; iron.
© The Author(s), 2015.