| Cross-sectional case-control studies  

Multimodal neuroimaging in post-COVID syndrome and correlation with cognition

86 patients with post-COVID syndrome (PCS) and 36 healthy controls with no exposure to SARS-CoV-2 were enrolled in the study. MRI imaging and cognitive assessment were perfomed 11 months after SARS-CoV-2 infection. Whole-brain functional connectivity (FC), voxel-based morphometry (VBM) and diffusion tensor imaging analyses were performed. PCS patients showed hypoconnectivity between left and right parahippocampal areas, and between bilateral orbitofrontal and cerebellar areas compared to controls.

VBM analysis did not show any significant grey matter (GM) atrophy if corrected for multiple comparisons, but exploratory analyses revealed atrophy in parahippocampal gyrus, frontal gyrus, anterior cerebellum, occipital lobe, and bilateral superior temporal lobe. PCS patients had increased white matter hyperintensities, with increased total lesion volume and number. They also had reduced mean diffusivity and axial diffusivity in the Corpus Callosum, Forceps Minor, Middle Longitudinal Fasciculus, Uncinate tract, and Fronto-Occipital fasciculus compared to controls. GM atrophy showed significant relationships with cognitive impairment, especially between attention, processing speed and working memory and left parahippocampus, left superior temporal gyrus, and anterior cerebellum. FC alterations between bilateral frontal superior orbital cortex and cerebellar vermis correlated with memory (free and delayed recall). Cognitive and imaging deficits were higher in hospitalized patients compared to non-hospitalized patients.

Díez-Cirarda M

doi: 10.1093/brain/awac384