Structural and Functional Connectivity Substrates of Cognitive Impairment in Multiple Sclerosis
Jian Zhang1, Rosa Cortese1, Nicola De Stefano1
1Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy.
Frontiers in Neurology
|July 26, 2021
Summary
Cognitive impairment (CI) in multiple sclerosis (MS) is linked to changes in brain connectivity. Advanced magnetic resonance imaging (MRI) techniques reveal structural and functional alterations underlying CI in MS patients.
Area of Science:
- Neuroimaging
- Neurology
- Medical Physics
Background:
- Cognitive impairment (CI) affects 43-70% of multiple sclerosis (MS) patients, impacting attention, memory, processing speed, and executive functions.
- Altered structural connectivity (SC) and functional connectivity (FC) are increasingly recognized as key substrates of CI in MS.
- Advanced magnetic resonance imaging (MRI) techniques offer novel insights into these connectivity alterations.
Purpose of the Study:
- To review recent advances in MRI techniques for assessing SC and FC in MS.
- To explore the potential of these techniques in understanding the pathological substrates of CI in MS.
Main Methods:
- Review of diffusion tensor imaging (DTI) and advanced diffusion MRI techniques (DKI, DSI, HARDI, NODDI) for SC assessment.
- Analysis of task-based and resting-state functional MRI (fMRI) methods (seed-based, ICA, graph analysis) for FC assessment.
- Exploration of SC-FC relationships using novel MRI analysis methods.
Main Results:
- Traditional DTI measures and novel diffusion MRI techniques provide insights into white matter tract alterations in MS-related CI.
- fMRI methods reveal adaptive and maladaptive functional reorganization mechanisms associated with CI in MS.
- Emerging MRI analyses highlight the importance of SC-FC relationships in understanding CI pathogenesis.
Conclusions:
- Advanced MRI techniques, including novel diffusion methods and sophisticated fMRI analyses, are crucial for elucidating the complex connectivity alterations in MS-related CI.
- Understanding SC and FC alterations, and their interrelationships, is key to deeper insights into the pathological substrates of CI in MS.
- Continued development and application of these MRI techniques hold significant potential for future research and clinical applications in MS.
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