Unmasking Covid-19: Cerebral consequences from a neuroimaging perspective

The aim of this thesis was to investigate intracerebral abnormalities using imaging techniques,
specifically the prevalence and incidence of cerebrovascular MRI markers and vessel wall abnormalities
in hospitalized COVID-19 patients. Additionally, we examined the structural white matter (WM) integrity
in relation to blood pressure variability (BPV) and long-term clinical outcomes, and explored PET/CT
tracer uptake by αvβ3 integrins as a marker for carotid endothelial activation. Brain MRI analyses
revealed a higher prevalence of white matter hyperintensities (WMH) but no significant impact of
COVID-19 on cerebrovascular markers. Intracranial vessel wall enhancement was observed in 21% of
patients, yet its causal link to COVID-19 remains unclear. Furthermore, BPV was associated with
decreased WM integrity. If a causal relationship is established, continuous monitoring during
hospitalization could help identify patients at risk for cerebral damage. PET/CT imaging showed no
significant carotid endothelial activation but indicated an inflammatory response in the
cardiopulmonary system. In conclusion, this thesis demonstrated that COVID-19 has a limited impact
on cerebrovascular MRI and PET/CT markers shortly after hospitalization, with observed abnormalities
primarily explained by pre-existing cardiovascular risk factors. We recommend establishing research
readiness in advance to avoid wasting valuable time during the early phases of future pandemics.