Differential Gray Matter Vulnerability in the 1 Year Following a Clinically Isolated Syndrome

International audienc

Microstructural analyses of the posterior cerebellar lobules in relapsing-onset multiple sclerosis and their implication in cognitive impairment.

The posterior cerebellar lobules seem to be the anatomical substrate of cognitive cerebellar processes, but their microstructural alterations in multiple sclerosis (MS) remain unclear.To correlate diffusion metrics in lobules VI to VIIIb in persons with clinically isolated syndrome (PwCIS) and in cognitively impaired persons with MS (CIPwMS) with their cognitive performances.Sixty-nine patients (37 PwCIS, 32 CIPwMS) and 36 matched healthy subjects (HS) underwent 3T magnetic resonance imaging, including 3D T1-weighted and diffusion tensor imaging (DTI). Fractional anisotropy (FA) and mean diffusivity (MD) were calculated within each lobule and in the cerebellar peduncles. We investigated the correlations between cognitive outcomes and the diffusion parameters of cerebellar sub-structures and performed multiple linear regression analysis to predict cognitive disability.FA was generally lower and MD was higher in the cerebellum and specifically in the vermis Crus II, lobules VIIb and VIIIb in CIPwMS compared with PwCIS and HS. In hierarchical regression analyses, 31% of the working memory z score variance was explained by FA in the left lobule VI and in the left superior peduncle. Working memory was also associated with MD in the vermis Crus II. FA in the left lobule VI and right VIIIa predicted part of the information processing speed (IPS) z scores.DTI indicators of cerebellar microstructural damage were associated with cognitive deficits in MS. Our results suggested that cerebellar lobular alterations have an impact on attention, working memory and IPS

First clinical inflammatory demyelinating events of the central nervous system in a population aged over 70 years: A multicentre study

International audienceFew data are available regarding patients with very late-onset inflammatory demyelinating events. (VLO-IDE).Objectives: The aim of this study was to describe the clinical, biological, and radiological characteristics and aetiological diagnosis of very late first inflammatory demyelinating events of the central nervous system.Methods: We conducted a national descriptive retrospective multicentre study on a case series of patients aged >70 years at the time of VLO-IDE. Patients were recruited from a national call on behalf of the 'Société Francophone de la Sclérose en Plaques' (French Multiple Sclerosis Society).Results: Twenty-five patients were referred (F:M sex ratio 2.1:1). The most frequent clinical impairment was a spinal cord deficit (23/25), usually severe (disability score, median EDSS 4.5 [2-9.5]). Spinal cord lesions were usually extensive, spanning at least three segments (11/25), and large brain lesions were also observed (lesions >20 mm in 6/25). The final aetiological diagnoses comprised multiple sclerosis (9/25), neuromyelitis optica spectrum disorders (7/25), neurosystemic lupus erythematosus (2/25), transverse myelitis without aetiological diagnosis (6/25) and optic neuritis (1/25).Conclusions: This study highlights a particular phenotype of first clinical inflammatory demyelinating events in predominantly female patients aged >70 years who have severe motor impairment with common longitudinal extensive myelitis and large and common very active radiological inflammatory lesions. Neuromyelitis optica spectrum disorders seem overrepresented

Correlations between MD and cognitive outcome.

<p>Correlations between MD and cognitive outcome.</p

Comparisons in MD between CIS, MS and HC.

<p>Comparisons in MD between CIS, MS and HC.</p

Multivariate analysis model 2 –Cognitive prediction and MD analysis.

<p>Multivariate analysis model 2 –Cognitive prediction and MD analysis.</p

Microstructural analyses of the posterior cerebellar lobules in relapsing-onset multiple sclerosis and their implication in cognitive impairment - Fig 1

<p>A: Detailed image processing used to obtain lobular and peduncular diffusity data. Cropping and non-linear registration of T1w images over the SUIT template and ROI delineation. B: Registration of the diffusivity map using the transformation estimated with the T1w, diffusivity estimation into ROI. C: Non-linear registration of diffusivity maps and estimation within ROI determined by the JHU-ICBM-DTI-81 WM atlas (FSL).</p

Multivariate analysis model 1 –Cognitive prediction and FA analysis.

<p>Multivariate analysis model 1 –Cognitive prediction and FA analysis.</p