Background: Structural cortical networks (SCNs) represent patterns of coordinated morphological modifications in cortical areas, and they present the advantage of being extracted from previously acquired clinical magnetic resonance imaging (MRI) scans. SCNs have shown pathophysiological changes in many brain disorders, including multiple sclerosis.
Objective: To investigate alterations of SCNs at the individual level in patients with clinically isolated syndrome (CIS), thereby assessing their clinical relevance.
Methods: We analyzed baseline data collected in a prospective multicenter (MAGNIMS) study. CIS patients (n = 60) and healthy controls (n = 38) underwent high-resolution 3T MRI. Measures of disability and cognitive processing were obtained for patients. Single-subject SCNs were extracted from brain 3D-T1 weighted sequences; global and local network parameters were computed.
Results: Compared to healthy controls, CIS patients showed altered small-world topology, an efficient network organization combining dense local clustering with relatively few long-distance connections. These disruptions were worse for patients with higher lesion load and worse cognitive processing speed. Alterations of centrality measures and clustering of connections were observed in specific cortical areas in CIS patients when compared with healthy controls.
Conclusion: Our study indicates that SCNs can be used to demonstrate clinically relevant alterations of connectivity in CIS.
Keywords: Magnetic resonance imaging; clinically isolated syndrome; graph theory; gray matter; multicenter study; multiple sclerosis; structural cortical networks.
Disrupted subject-specific gray matter network properties and cognitive dysfunction in type 1 diabetes patients with and without proliferative retinopathy.Hum Brain Mapp. 2016 Mar;37(3):1194-208. doi: 10.1002/hbm.23096. Epub 2015 Dec 23. Hum Brain Mapp. 2016. PMID: 26700243
Impaired small-world efficiency in structural cortical networks in multiple sclerosis associated with white matter lesion load.Brain. 2009 Dec;132(Pt 12):3366-79. doi: 10.1093/brain/awp089. Brain. 2009. PMID: 19439423 Free PMC article.
Structural covariance networks relate to the severity of epilepsy with focal-onset seizures.Neuroimage Clin. 2018;20:861-867. doi: 10.1016/j.nicl.2018.09.023. Epub 2018 Sep 26. Neuroimage Clin. 2018. PMID: 30278373 Free PMC article.
The association of cognitive impairment with gray matter atrophy and cortical lesion load in clinically isolated syndrome.Mult Scler Relat Disord. 2016 Nov;10:14-21. doi: 10.1016/j.msard.2016.08.008. Epub 2016 Aug 16. Mult Scler Relat Disord. 2016. PMID: 27919482
Resting state networks change in clinically isolated syndrome.Brain. 2010 Jun;133(Pt 6):1612-21. doi: 10.1093/brain/awq058. Epub 2010 Mar 30. Brain. 2010. PMID: 20356855