title: Prevalence of grey matter pathology in early multiple sclerosis assessed by magnetization transfer ratio imaging.
abstract: The aim of the study was to assess the prevalence, the distribution and the impact on disability of grey matter (GM) pathology in early multiple sclerosis. Eighty-eight patients with a clinically isolated syndrome with a high risk developing multiple sclerosis were included in the study. Forty-four healthy controls constituted the normative population. An optimized statistical mapping analysis was performed to compare each subject's GM Magnetization Transfer Ratio (MTR) imaging maps with those of the whole group of controls. The statistical threshold of significant GM MTR decrease was determined as the maximum p value (p<0.05 FDR) for which no significant cluster survived when comparing each control to the whole control population. Using this threshold, 51% of patients showed GM abnormalities compared to controls. Locally, 37% of patients presented abnormalities inside the limbic cortex, 34% in the temporal cortex, 32% in the deep grey matter, 30% in the cerebellum, 30% in the frontal cortex, 26% in the occipital cortex and 19% in the parietal cortex. Stepwise regression analysis evidenced significant association (p = 0.002) between EDSS and both GM pathology (p = 0.028) and T2 white matter lesions load (p = 0.019). In the present study, we evidenced that individual analysis of GM MTR map allowed demonstrating that GM pathology is highly heterogeneous across patients at the early stage of MS and partly underlies irreversible disability.
authors.affiliation: Pôle de Neurosciences Cliniques, Service de Neurologie, Assistance Publique Hôpitaux de Marseille, CHU Timone, Marseille, France.
authors.forename: Lydie
authors.initials: L
authors.lastname: Crespy
authors.forename: Wafaa
authors.initials: W
authors.lastname: Zaaraoui
authors.forename: Mathias
authors.initials: M
authors.lastname: Lemaire
authors.forename: Audrey
authors.initials: A
authors.lastname: Rico
authors.forename: Anthony
authors.initials: A
authors.lastname: Faivre
authors.forename: Françoise
authors.initials: F
authors.lastname: Reuter
authors.forename: Irina
authors.initials: I
authors.lastname: Malikova
authors.forename: Sylviane
authors.initials: S
authors.lastname: Confort-Gouny
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Cozzone
authors.forename: Jean
authors.initials: J
authors.lastname: Pelletier
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Ranjeva
authors.forename: Bertrand
authors.initials: B
authors.lastname: Audoin
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D003952:Diagnostic Imaging; D018450:Disease Progression; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D055815:Young Adult