QSM venography measurement of regional cerebral blood oxygenation in PASC and ME/CFS

Motivation: Patients with long COVID share many symptoms, such as fatigue and cognitive issues, with individuals with ME/CFS. Studying the similarities and differences between these related conditions can deepen our understanding of their disease mechanisms. Goal(s): This study aims to measure regional cerebral oxygen extraction fraction (OEF) in ME/CFS patients with and without long COVID and compare them to controls. Approach: Using QSM venography, we established a calibration curve and quantified oxygenation in major brain-draining veins. Results: We found significantly lower oxygenation in the straight sinus in PASC patients compared to controls, suggesting elevated OEF in the deep brain regions. Impact: This research reveals altered cerebral oxygenation in PASC ME/CFS patients compared to healthy controls, highlighting differences in oxygen extraction. These findings support further studies on brain oxygen metabolism in post-viral fatigue, with potential diagnostic and therapeutic implications.