Microstructural and susceptibility alterations in white matter and cerebellum are linked to fatigue and cognitive dysfunction in long COVID

Motivation: The biological mechanisms of impactful symptoms of the long-COVID syndrome such as fatigue and cognitive dysfunction, are still unknown. Goal(s): The goal of this study was to understand the correlation between microstructural and susceptibility MRI metrics with fatigue and cognitive scores voxel-wise to identify the most involved regions and networks. Approach: A multimodal MRI protocol was acquired in healthy controls, people recovered from COVID19 or with long-COVID, together with clinical assessments. Results: The relationship between MRI metrics and the clinical scores was analyzed. Results showed that white matter and cerebellar regions are the most involved, with inflammation and iron-myelin dysregulation explaining the symptoms. Impact: This work impacts on our understanding of fatigue and cognitive impairment, impactful symptoms of the long-COVID syndrome, emphasizing the role of diffusion MRI and susceptibility mapping models in detecting microstructural and susceptibility alterations voxel-wise.