[Axonal damage in multiple sclerosis]

The presence of axonal lesions in plaques of demyelination in patients with multiple sclerosis (MS) has been known for many years. Traditionally it was believed that axonal loss occurred in chronic lesions. However, demonstration of pathological degeneration in active plaques, use of new resonance techniques such as spectroscopy or the transfer of magnetization, showing axonal damage in white matter of apparently normal aspect, and the presence of axonal neurofilaments in the cerebrospinal fluid during the episode has made it necessary to reconsider the contribution made by axonal damage to the pathogenesis of MS. Besides, recent studies have shown that a factor present in the cerebrospinal fluid of patients with MS may contribute to the induction of neuronal apoptosis. These facts, apart from their pathogenic implications and consequent clinical repercussions, will affect investigation of alternative treatments for this disorder, and by means of clinico-immunoradiological correlation will help to define the prognosis of the course of the disorder in these patients.