Diagnostic criteria and definition of the clinical course of multiple sclerosis

This paper reviews the validity of clinical diagnostic criteria and clinica l course classification. Validation based on the pathological verification is not available. MS diagnosis remains clinical based on the objective demo nstration of dissemination of lesions suggestive of MS in both time and spa ce. Also clinical features are not specific and sensitive enough. MRI is pr imordial. MRI diagnosis criteria are discussed. Clinical course classificat ion is difficult in regard to the extreme heterogeneity of the disease. Cla ssical distinction between recurrent and progressive forms is reviewed from natural history studies and recent MRI and pathological findings. Recent s tudies focus on presentation including monosymptomatic disease and primary progressive forms.