Longitudinal MR Imaging of iron in multiple sclerosis:
An imaging marker of disease
This study investigated the relationship between MRI markers (phase imaging and transverse relaxation (R2*) mapping at 4.7T) of iron content and disease severity in 17 people with MS and 17 controls over a two-year period. The researchers found that R2* mapping using two-year-difference measurements had the highest correlation to disease severity compared with R2* mapping using single-time measurements and phase imaging. There were significant increases in R2* during two years in the substantia nigra and globus pallidus, which are both predictors of disease in regression analysis.
This study demonstrates that there are significant changes in deep grey matter iron content in MS during two years measured with MR imaging, and the changes strongly correlate with physical disability. Also longitudinal measurements may produce a higher correlation to disease severity than single-time measurements as baseline iron is variable among subjects.