Demyelinating Disorders of the Adult Central Nervous System: A Pictorial Review of MR Imaging Findings

CNS demyelinating disorders encompass a wide spectrum of syndromes affecting the integrity of myelin in the brain. These disorders can be classified into primary and secondary processes with secondary causes being further subclassified into infectious, alcohol-related, iatrogenic/toxic, and vascular, depending on the etiology. Unfortunately, the imaging appearances of the resulting white matter lesions are often nonspecific in nature. An understanding of the clinical features and parenchymal patterns of involvement of demyelinating diseases is essential to permit the radiologist to generate a narrow differential diagnosis, which the clinician can refine further with knowledge of the patient's history and laboratory testing. This pictorial review presents the imaging features of demyelinating disorders. Imaging features allowing their optimal differentiation will be discussed.