How is multiple sclerosis (MS) diagnosed?

The diagnosis of MS is based on the association of neurological symptoms associated with the presence of inflammatory plaques on MRI, which respond to spatial dissemination (brain, spinal cord, optic nerve) and temporal dissemination (inflammatory plaques of different ages or which appear over time).
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The diagnosis of MS is based on the observation by MRI of inflammatory plaques visible as a hypersignal in the brain and spinal cord, disseminated over time (recent and old lesions) and space (lesions involving at least two regions between 4 possible locations in the central nervous system).

Two MRI scans of the same subject showing dissemination in space (left) with inflammatory lesions of the periventricular and juxtacortical white matter and dissemination in time (right) with lesions of different ages (contrast).

The course of multiple sclerosis

The symptoms of the disease vary greatly from one patient to another. Similarly, the progression and time to onset of irreversible disability vary according to the ability of each sufferer to “repair” his or her brain lesions.

Whatever the type of multiple sclerosis, there are criteria for defining the activity of the disease and monitoring its progress. The existence of relapses, the progression of the EDSS (Expended Disability Status Scale) score and the appearance of new lesions visible on MRI are recognised as markers of disease activity.


At the Paris Brain Institute

The team led by Profs Catherine Lubetzki and Bruno Stankoff has shown that the activation of microglia, the brain’s resident immune cells, in lesions is a promising biomarker of the progression of disability in patients. These results offer great hope for adapting the treatment of patients suffering from multiple sclerosis, evaluating new therapies and preventing the progression of disability as far as possible.


Last updated May 2024.