Marek Tarčák, Veronika Vajdová
Sclerosis multiplex (SM) is a disease of the central nervous system (CNS) characterized with the inflammation, demyelination and neurodegeneration and it is very often a non-traumatic cause of neurological disability in young people(1). Episodes of focal infiltration of nervous issues with lymphocytes with subsequent destruction of myelin and axons are typical(2). The disease presents in each patient individually and while one group of patients reaches through their life a low score of disability (expressed with Kurtze scale of disability, Expand Disability Status Score - EDSS), others suffering from aggressive SM form reach a high EDSS in a relatively short time. In the pathogenesis of the disease many mechanisms are applied, which do not cause just local damage of the tissue but also lead to an important reduction of the parenchyma in the brain and spinal cord and finally to a permanent disability of a patient.
At present, brain and spinal cord imaging with magnetic resonance (MRI) has a significant role in the differential SM diagnosis, in monitoring of the activities of the disease itself, in the choice of a suitable therapy for a patient and evaluation of its effectiveness, in early detection of adverse effects of the treatment and in determination of the diagnosis. MRI examination is characterized by high sensitivity for early detection of the disease. However, the specificity of the examination is low. In patients with Clinically Isolated Syndromes (CIS) as optic neuritis, the syndrome of the brain stem or syndrome of the spinal cord, MRI might support or replace clinical manifestations based on the evaluation of the presence of demyelination lesions in the development of the disease. Not each CIS progresses to SM; however, the presence of T2 hyper intensive lesions on the MRI examination is related to the higher risk of SM origination and gradual disability. The MRI examination is also a key one in the exclusion of other diseases, which might simulate SM in the clinical picture(3,4).