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Magnetic resonance imaging (MRI) of the brain and spinal cord plays a crucial role in the diagnosis and monitoring of multiple sclerosis (MS). There is conclusive evidence that brain and spinal cord MRI findings in early disease stages also provide relevant insight into individual prognosis. This includes prediction of disease activity and disease progression, the accumulation of long-term disability and the conversion to secondary progressive MS. The extent to which these MRI findings should influence treatment decisions remains a subject of ongoing discussion. The aim of this review is to present and discuss the current knowledge and scientific evidence regarding the utility of MRI at early MS disease stages for prognostic classification of individual patients. In addition, we discuss the current evidence regarding the use of MRI in order to predict treatment response. Finally, we propose a potential approach as to how MRI data may be categorized and integrated into early clinical decision making.
Can MRI help select appropriate therapy for recently diagnosed multiple sclerosis? MS is a chronic autoimmune disease of the brain and spinal cord that causes physical and cognitive disability. Initially, most people with MS (pwMS) experience attacks of new symptoms and periods of partial recovery; this is called relapsing-remitting MS (RRMS). RRMS transitions to secondary progressive MS (SPMS), where there is a gradual worsening of disability. MS medications dampen parts of the immune system. They reduce the risk of relapses and delay transition to SPMS if started early. Once a person has SPMS, treatment can slow but not stop further deterioration. MS medications vary in their effects on the immune system, level of efficacy, and treatment risks. The course of MS is highly individual. When starting therapy, it can therefore be difficult to decide whether a drug with lower or higher efficacy is required. Some of the acute and chronic inflammatory changes in MS are shown as focal lesions ('spots') on MRI of the brain and spinal cord. They are very useful for diagnosing MS and determining disease activity. Even if there are no relapses, new lesions indicate that a MS medication is not fully effective. In addition, MRI provides a snapshot of tissue damage that has accumulated up to the examination. At the time of diagnosis, MRI reflects the natural history of MS in the individual, even before the first attack, and contains prognostic information. We review studies that investigate an association between certain MRI findings obtained early after the initial attack and the later course of MS. We propose that these metrics can be applied to a concept of grading and staging of MS as well as estimating functional reserve. We review thresholds that identify pwMS at risk of disability progression and transition to SPMS, who should be recommended highly effective therapy first line. Leveraging the prognostic capabilities of MRI may support initial treatment decisions.
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BACKGROUND: Atrophy of white and grey matter volumes occurs early in the brains of people with multiple sclerosis (pwMS) and has great clinical relevance. In clinical trials, brain atrophy can be quantified by magnetic resonance imaging (MRI) with automated software tools. METHODS: In this study, we analyze volumes of various brain regions with the software "md brain" based on routine MRI scans of 53 pwMS in a real-world setting. We compare brain volumes of pwMS with an EDSS ≥ 3.5 and a disease duration ≥ 10 years to the brain volumes of pwMS with an EDSS < 3.5 and a disease duration < 10 years as well as with or without immunotherapy. RESULTS: pwMS with an EDSS ≥ 3.5 and a disease duration ≥ 10 years had significantly lower volumes of the total brain, the grey matter and of the frontal, temporal, parietal and occipital lobe regions as compared to pwMS with an EDSS < 3.5 and a disease duration < 10 years. Regional brain volumes were significantly lower in pwMS without immunotherapy. CONCLUSIONS: The study showed that higher EDSS, longer disease duration and absence of immunotherapy was associated with lower volumes in a number of brain regions. Further real-world studies may include larger patient cohorts in longitudinal analyses.
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Genome-wide association studies identified a single nucleotide polymorphism (SNP) downstream of the transcription factor Sox8, associated with an increased risk of multiple sclerosis (MS). Sox8 is known to influence oligodendrocyte terminal differentiation and is involved in myelin maintenance by mature oligodendrocytes. The possible link of a Sox8 related SNP and MS risk, along with the role of Sox8 in oligodendrocyte physiology prompted us to investigate its relevance during de- and remyelination using the cuprizone model. Sox8-/- mice and wildtype littermates received a cuprizone diet for 5 weeks (wk). Sox8-/- mice showed reduced motor performance and weight compared to wildtype controls. Brains were histologically analysed at the maximum of demyelination (wk 5) and on two time points during remyelination (wk 5.5 and wk 6) for oligodendroglial, astroglial, microglial and myelin markers. We identified reduced proliferation of oligodendrocyte precursor cells at wk 5 as well as reduced numbers of mature oligodendrocytes in Sox8-/- mice at wk 6. Moreover, analysis of myelin markers revealed a delay in remyelination in the Sox8-/- group, demonstrating the potential importance of Sox8 in remyelination processes. Our findings present, for the first time, compelling evidence of a significant role of Sox8 in the context of a disease model.