Keywords: Contrast mechanisms: Susceptibility
QSM and subvoxel QSM methods have facilitated the quantification of brain iron and myelin in neuroimaging research. These quantitative imaging techniques offer valuable insights into neurodegenerative diseases such as Parkinson's and the potential for studying tissue subvoxel susceptibilities outside of the brain. However, accurately quantifying susceptibility values and distinguishing between different sources of susceptibility pose significant challenges that necessitate robust modeling and analysis techniques. Validating susceptibility measurements against histological or other reference standards and establishing standardized protocols for data acquisition, processing, and validation are crucial steps to ensure the reliability and reproducibility of results across various studies.