Brain Alterations in Covid Recovered Revealed by Susceptibility-Weighted Magnetic Resonance Imaging

The increasing number of reports of mild to severe psychological, behavioral, and cognitive sequelae in COVID-19 survivors motivates a need for a thorough assessment of the neurological effects of the disease. In this regard, we have conducted a neuroimaging study to understand the neurotropic behavior of the coronavirus. We hypothesize that the COVID-recovered subjects have developed alterations in the brain which can be measured through susceptibility differences in various regions of the brain when compared to healthy controls (HCs). Hence, we performed our investigations on susceptibility-weighted imaging (SWI) volumes. Fatigue, being of the most common symptoms of Long COVID, has also been studied in this work. SWI volumes of 46 COVID and 30 HCs were included in this study. The COVID patients were imaged within six months of their recovery. We performed an unpaired two-sample t-test over the pre-processed SWI volumes of both groups and multiple linear regression was performed to observe group differences and the correlation of fatigue with SWI values. The group analysis showed that COVID-recovered subjects had significantly higher susceptibility imaging values in regions of the frontal lobe and the brain stem. The clusters obtained in the frontal lobe primarily show differences in the white matter regions. The COVID group also demonstrated significantly higher fatigue levels than the HC group. The regression analysis on the COVID group yielded clusters in the anterior cingulate gyrus and midbrain, which exhibited negative correlations with fatigue scores. This study suggests an association of Long COVID with prolonged effects on the brain and indicates the viability of the SWI modality for analysis of post-COVID symptoms.