Open AccessChanges in structural network are associated with cortical demyelination in early multiple sclerosis
Author(s) -
Mangeat Gabriel,
Badji Atef,
Ouellette Russell,
Treaba Constantina A.,
Herranz Elena,
Granberg Tobias,
Louapre Céline,
Stikov Nikola,
Sloane Jacob A.,
Bellec Pierre,
Mainero Caterina,
CohenAdad Julien
Publication year - 2018
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.23993
Subject(s) - multiple sclerosis , white matter , myelin , diffusion mri , analysis of variance , correlation , neuroscience , medicine , psychology , pathology , magnetic resonance imaging , central nervous system , radiology , mathematics , immunology , geometry
The aim of this study was to investigate the interplay between structural connectivity and cortical demyelination in early multiple sclerosis. About 27 multiple sclerosis patients and 18 age‐matched controls underwent two MRI scanning sessions. The first was done at 7T and involved acquiring quantitative T 1 and T 2 * high‐resolution maps to estimate cortical myelination. The second was done on a Connectom scanner and consisted of acquiring high angular resolution diffusion‐weighted images to compute white matter structural connectivity metrics: strength, clustering and local efficiency. To further investigate the interplay between structural connectivity and cortical demyelination, patients were divided into four groups according to disease‐duration: 0–1 year, 1–2 years, 2–3 years, and >3 years. ANOVA and Spearman's correlations were used to highlight relations between metrics. ANOVA detected a significant effect between disease duration and both cortical myelin ( p = 2 × 10 −8 ) and connectivity metrics ( p < 10 −4 ). We observed significant cortical myelin loss in the shorter disease‐duration cohorts (0–1 year, p = .0015), and an increase in connectivity in the longer disease‐duration cohort (2–3 years, strength: p = .01, local efficiency: p = .002, clustering: p = .001). Moreover, significant covariations between myelin estimation and white matter connectivity metrics were observed: Spearman's Rho correlation coefficients of 0.52 ( p = .0003), 0.55 ( p = .0001), and 0.53 ( p = .0001) for strength, local efficiency, and clustering, respectively. An association between cortical myelin loss and changes in white matter connectivity in early multiple sclerosis was detected. These changes in network organization might be the result of compensatory mechanisms in response to the ongoing cortical diffuse damage in the early stages of multiple sclerosis.