Fast Multipole Method-Enhanced Boundary Element Modeling for Total Field Inversion in Quantitative Susceptibility Mapping

Motivation: The study aims to improve quantitative susceptibility mapping (QSM) precision at region of interest (ROI) boundaries where background field interference affects accuracy. Goal(s): To introduce a novel boundary element method total field inversion (BEM-TFI) enhanced by the fast multipole method (FMM) for high-resolution QSM. Approach: A comparative assessment of BEM-TFI technique was performed with traditional QSM methods, utilizing in-vivo data and simulated field maps to determine inversion quality and background field removal efficiency. Results: Enhanced by FMM, the BEM-TFI method demonstrated significant improvements in accurately discerning tissue susceptibility from background noise, indicating a substantial advancement in the outcomes of QSM. Impact: The BEM-TFI enhancement in QSM accuracy allows for more detailed characterization of the brain's cortex, potentially enriching neuroscientific research and elevating the quality of neuroimaging data.