White matter (WM) disease is a relatively common finding in Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) studies in adults.When we think about this large group of disease we instinctively focus on multiple esclerosis, but there is a vast heterogeneous group with a wide spectrum of appearances and presentations. The interpretation of those diseases is complex and the way that the normal myelination shows alterations remains poorly understood in many cases. In this review we try to determine notable patterns in CT and MRI...

To understand the demylinating disorders, first we have to know about normal WM: myelination begins early in the third month postpartum and the most rapid period of myelination occurring in the first two years of life, the oligodendrocytes produce the myelin that covers the axons of neurons wich join the glial cells to be the main components of the normal WM. The lipid content of myelin is extraordinarily high and in less quantity water, a fact to consider in the MRI studies. The diseases that...

AUTOINMUNE DEMYELINATION Inmune-mediated events can cause myelin loss and oligodendrocyte death leading to axonal degeneration, this complex phatology remains unclear: some investigations theorice about genetically susceptible individuals and if environmental factors can contribute to triggered the disease [1][2]. Neuromyelitis optica (NMO): The mean age at presentation is in the fourth decade of life, with a stronger female predilection (F:M ratio 3:1) and more frequently found in caucasian patients.The classic presentarion is optic neuritis with WM nonspecific lesions and longitudinally extensive myelitis, with a relapsing course...

WM diseases show similar presentation patterns in very different aetiologies. The radiologist must know the normal myelination and recognice the possible injuries to know what type of disease should consider to establish the differential diagnosis: this can avoid delays in treatment and unnecessary testing.

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