Combining quantitative susceptibility mapping (QSM) with R2* mapping is useful for characterizing heterogeneity in multiple sclerosis (MS) lesions, according to a study of 306 MS lesions from 24 MS patients who underwent 7T MRI.
Investigators calculated maps of R2*, frequency, and qualitative susceptibility using acquired multiecho gradient echo (GRE) phase data and found:
• 93% of lesions showed hypointensity on R2*.
• Susceptibility contrast in lesions varied with 40% being isointense and 58% hyperintense in the lesion core.
• Correlations between R2* and susceptibility were found in hyperintense lesions but not in isointense ones.
• 74% of periventricular, 53% of subcortical, and 38% of juxtacortical lesions were found to be susceptibility hyperintense.
Citation: Li X, Harrison DM, Liu H, et al. Magnetic susceptibility contrast variations in multiple sclerosis lesions. J Magn Reson Imaging. 2015. doi: 10.1002/jmri.24976. [Epub ahead of print]