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Signal quality as Achilles' heel of graph theory in functional magnetic resonance imaging in multiple sclerosis.

ABSTRACT: Graph-theoretical analysis is a novel tool to understand the organisation of the brain.We assessed whether altered graph theoretical parameters, as observed in multiple sclerosis (MS), reflect pathology-induced restructuring of the brain's functioning or result from a reduced signal quality in functional MRI (fMRI). In a cohort of 49 people with MS and a matched group of 25 healthy subjects (HS), we performed a cognitive evaluation and acquired fMRI. From the fMRI measurement, Pearson correlation-based networks were calculated and graph theoretical parameters reflecting global and local brain organisation were obtained. Additionally, we assessed metrics of scanning quality (signal to noise ratio (SNR)) and fMRI signal quality (temporal SNR and contrast to noise ratio (CNR)). In accordance with the literature, we found that the network parameters were altered in MS compared to HS. However, no significant link was found with cognition. Scanning quality (SNR) did not differ between both cohorts. In contrast, measures of fMRI signal quality were significantly different and explained the observed differences in GTA parameters. Our results suggest that differences in network parameters between MS and HS in fMRI do not reflect a functional reorganisation of the brain, but rather occur due to reduced fMRI signal quality.

SUBMITTER: Baijot J

PROVIDER: S-EPMC8016888 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Signal quality as Achilles' heel of graph theory in functional magnetic resonance imaging in multiple sclerosis.

Baijot Johan J Denissen Stijn S Costers Lars L Gielen Jeroen J Cambron Melissa M D'Haeseleer Miguel M D'hooghe Marie B MB Vanbinst Anne-Marie AM De Mey Johan J Nagels Guy G Van Schependom Jeroen J

Scientific reports 20210401 1

Graph-theoretical analysis is a novel tool to understand the organisation of the brain.We assessed whether altered graph theoretical parameters, as observed in multiple sclerosis (MS), reflect pathology-induced restructuring of the brain's functioning or result from a reduced signal quality in functional MRI (fMRI). In a cohort of 49 people with MS and a matched group of 25 healthy subjects (HS), we performed a cognitive evaluation and acquired fMRI. From the fMRI measurement, Pearson correlatio ...[more]

PMID: 33795779

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Signal quality as Achilles' heel of graph theory in functional magnetic resonance imaging in multiple sclerosis.

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Signal quality as Achilles' heel of graph theory in functional magnetic resonance imaging in multiple sclerosis.

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