Nonsusceptibility frequency shift reveals subtypes of multiple sclerosis lesions and predicts 5-year disappearance of paramagnetic rim

Multiple sclerosis lesions have different types and stages that are challenging to distinguish by conventional MRI. We recently presented DEEPOLE QUASAR, a reconstruction technique that yields nonsusceptibility frequency maps as a novel MRI contrast. In this study, we translate the novel contrast into a tool for multiple sclerosis lesion assessment. We discuss the time course of nonsusceptibility frequency throughout different lesion stages. Within different paramagnetic rim lesions that are typically indistinguishable by conventional MRI, the nonsusceptibility frequency contrast showed hypo-, iso-, and hyperintense subtypes. At a 5-year follow-up, paramagnetic rims disappeared at significantly different proportions between these subtypes.