Comparative Characterisation of Susceptibility Weighted MRI for Brain White Matter Lesions in MS

Abstract

MR Images of the brain in Multiple Sclerosis (MS) show regions of signal abnormalities that can provide information for the diagnosis and for the pathogenesis of the disease. Two very commonly used MRI contrasts in this context are the T ₁ weighted (T ₁-w) and the FLAIR. This study shows that additional information can be extracted from the Susceptibility Weighted MRI (SWI) contrast. In particular, the signal and the contrast of white matter lesions in SWI are examined and compared to T ₁-w and FLAIR contrasts. The lesions are analysed into hypo- and hyper-intense. Additionally, the spatial distributions for the two lesion types are computed and summarised with their expected distance from the ventricles. The data from 19 MS patients and 23 controls have been acquired and examined. The results show the presence of two lesion classes in SWI for MS patients, while T ₁-w and FLAIR contrast mechanisms present only a single class each. The hypo-intense SWI lesions appear closer to the ventricles and are more correlated to the T ₁-w signal rather than the FLAIR signal.

We acknowledge the funding support of the European Commission through the MIBISOC project (Marie Curie Initial Training Network, FP7 PEOPLE-ITN-2008, GA n. 238819).