Contributions
Abstract: P514
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 21 Imaging
Background: There is a lack of longitudinal study exploring topological organization of functional brain networks at early stages of multiple sclerosis (MS) that could help to understand cognitive compensation.
Objectives: To assess potential brain functional reorganization at rest in patients with CIS (PwCIS) in a 1-year longitudinal study and characterize the relationships between brain reorganization and cognitive functioning.
Methods: 53 patients recruited less than 6 months after a CIS and 35 matched healthy controls (HC) underwent a 3T MRI scan including 3D T1 weighted images, fluid-attenuated inversion recovery and Resting-State fMRI. 45 PwCIS and 20 HC were rescanned 1 year after the first assessment. Destrieux parcellation was obtained using FreeSurfer. Graph-based network measures such as global and local efficiency (Eloc), betweenness centrality (BCN) and degree (Deg) were calculated. Hub disruption index (k) of each parameter was then determined using the slope of the following graph : (paramsubject - paramcontrolmean) = f(paramcontrolmean). Attention, working memory (WMem), episodic memory (EMem), executive functions (EF), visuoconstruction, and information processing speed (IPS) were assessed by a neuropsychological battery. Linear regression models were used to predict cognitive changes by baseline brain functional connectivity parameters. Correlations between functional connectivity and cognitive changes during one year of follow-up were performed.
Results: No global efficiency differences were observed neither at baseline nor at 1-year of follow-up between patients and HC. kBCN was significantly negative at baseline in patients (p< 0.05). At 1 year, patients kBCN switched to a significant positive value (p< 0.0001). kEloc and kDeg did not differ between patients and controls at baseline and showed a negative value after 1 year in patients (p< 0.0001). Visuo-spatial memory changes were predicted by baseline global efficiency in patients. WMem change was predicted by initial kEloc. Verbal EMem and Visuo-construction changes were both predicted by kBCN. Regarding changes during 1 year, global efficiency was positively correlated to IPS and kEloc to WMem in PwCIS.
Conclusion: For the first time, these results suggest dynamic changes of functional brain networks in patients at early stage of MS that are clinically relevant for cognition.
Disclosure: This study was supported by TEVA, Labex Translational Research And Advanced Imaging Laboratory (TRAIL) and ARSEP.
Koubiyr I : Personal grant from TRAIL.
Deloire M : Nothing to disclose.
Charre-Morin J : Nothing to disclose.
Saubusse A : Nothing to disclose.
Coupe P : Nothing to disclose.
Dulau C : received a speaker fee from BIOGEN.
Tourdias T : Nothing to disclose.
Besson P : Nothing to disclose.
Ranjeva JP : Nothing to disclose.
Pelletier J : Consulting fees and travels from Biogen, Sanofi-Genzyme, Novartis, Teva, Merck-Serono, Roche, Medday. Unconditional research grants from Biogen, Novartis, Roche and Merck-Serono.
Audoin B : Nothing to disclose.
Brochet B : Pr Brochet has received consultancy fees, speaker fees, research grants (non-personal), or honoraria from Novartis, Biogen-Idec, Merck, Bayer Schering, Roche, Medday, Bayer, Actelion, Teva and Genzyme Sanofi outside the submitted study.
Ruet A : has received consultancy fees, speaker fees, research grants (non-personal), or honoraria from Novartis, Biogen-Idec, Roche, Teva and Merck outside the submitted study.
Abstract: P514
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 21 Imaging
Background: There is a lack of longitudinal study exploring topological organization of functional brain networks at early stages of multiple sclerosis (MS) that could help to understand cognitive compensation.
Objectives: To assess potential brain functional reorganization at rest in patients with CIS (PwCIS) in a 1-year longitudinal study and characterize the relationships between brain reorganization and cognitive functioning.
Methods: 53 patients recruited less than 6 months after a CIS and 35 matched healthy controls (HC) underwent a 3T MRI scan including 3D T1 weighted images, fluid-attenuated inversion recovery and Resting-State fMRI. 45 PwCIS and 20 HC were rescanned 1 year after the first assessment. Destrieux parcellation was obtained using FreeSurfer. Graph-based network measures such as global and local efficiency (Eloc), betweenness centrality (BCN) and degree (Deg) were calculated. Hub disruption index (k) of each parameter was then determined using the slope of the following graph : (paramsubject - paramcontrolmean) = f(paramcontrolmean). Attention, working memory (WMem), episodic memory (EMem), executive functions (EF), visuoconstruction, and information processing speed (IPS) were assessed by a neuropsychological battery. Linear regression models were used to predict cognitive changes by baseline brain functional connectivity parameters. Correlations between functional connectivity and cognitive changes during one year of follow-up were performed.
Results: No global efficiency differences were observed neither at baseline nor at 1-year of follow-up between patients and HC. kBCN was significantly negative at baseline in patients (p< 0.05). At 1 year, patients kBCN switched to a significant positive value (p< 0.0001). kEloc and kDeg did not differ between patients and controls at baseline and showed a negative value after 1 year in patients (p< 0.0001). Visuo-spatial memory changes were predicted by baseline global efficiency in patients. WMem change was predicted by initial kEloc. Verbal EMem and Visuo-construction changes were both predicted by kBCN. Regarding changes during 1 year, global efficiency was positively correlated to IPS and kEloc to WMem in PwCIS.
Conclusion: For the first time, these results suggest dynamic changes of functional brain networks in patients at early stage of MS that are clinically relevant for cognition.
Disclosure: This study was supported by TEVA, Labex Translational Research And Advanced Imaging Laboratory (TRAIL) and ARSEP.
Koubiyr I : Personal grant from TRAIL.
Deloire M : Nothing to disclose.
Charre-Morin J : Nothing to disclose.
Saubusse A : Nothing to disclose.
Coupe P : Nothing to disclose.
Dulau C : received a speaker fee from BIOGEN.
Tourdias T : Nothing to disclose.
Besson P : Nothing to disclose.
Ranjeva JP : Nothing to disclose.
Pelletier J : Consulting fees and travels from Biogen, Sanofi-Genzyme, Novartis, Teva, Merck-Serono, Roche, Medday. Unconditional research grants from Biogen, Novartis, Roche and Merck-Serono.
Audoin B : Nothing to disclose.
Brochet B : Pr Brochet has received consultancy fees, speaker fees, research grants (non-personal), or honoraria from Novartis, Biogen-Idec, Merck, Bayer Schering, Roche, Medday, Bayer, Actelion, Teva and Genzyme Sanofi outside the submitted study.
Ruet A : has received consultancy fees, speaker fees, research grants (non-personal), or honoraria from Novartis, Biogen-Idec, Roche, Teva and Merck outside the submitted study.