Neuroimaging Modalities in Neuroimmunology

Magnetic resonance imaging (MRI) plays a central role in the diagnostic workup and clinical management of neuroimmunological diseases, including multiple sclerosis (MS). MRI is highly sensitive to visualize white matter signal abnormalities on T2-weighted images, and the characteristic appearance of demyelinating lesions has become well recognized. However, MRI is not pathologically specific, and differentiating MS from other (non-MS) conditions remains a challenge in the field. This chapter reviews the role of MRI in diagnosing and monitoring MS patients over time and discusses promising MR techniques that may increase the specificity of MRI for demyelination, including central vein imaging and cortical lesion detection, to help distinguish MS from other diagnoses. We also discuss possible applications of volumetric MRI as a way to monitor patients over time, and we highlight positron emission tomography (PET) methods that have been used in MS and may further our understanding of the biology of the disease, with particular focus on PET measures of microglial activation and remyelination.