Assessing Metabolic Dysfunction at Cerebral Microbleed Sites using Quantitative Oxygen Extraction Fraction MRI

Motivation: Cerebral microbleeds (CMBs) are hemosiderin deposits in the brain linked to multiple disease, including neurodegeneration. They are associated with vascular remodeling, blood-brain barrier dysfunction, and inflammatory processes, but their impact on neurologic function is not well understood. Goal(s): To investigate metabolic activity at CMB sites, using a recent oxygen extraction fraction (OEF) MRI technique, QQ, to characterize dysfunction compared to non-CMB brain tissue. Approach: QSM, SWI, and QQ MRI were conducted on 196 subjects. Regions of interest (ROIs) were analyzed for OEF at CMB sites versus surrounding tissue. Results: Decreased OEF at CMB locations, correlating with higher QSM values, indicating reduced metabolic function. Impact: CMB site decreased metabolic activity that worsens with increasing susceptibility suggests neurological functional damage occurrence, therapeutic targets focusing on restoring metabolic function, research directions into how CMBs disrupt local metabolism, and that QSM may serve as a biomarker for neurodegeneration.