In-silico study of internal gradient distribution effects on diffusion-weighted signals of white matter tracts models at 9.4 T

Motivation: Non-invasively detecting tissue microstructure changes associated with pathologies holds immense diagnostic promise. Our approach complements conventional DWI methods by capturing distinct microstructural information. Goal(s): We investigate the relationship between axon microstructure parameters and Internal Gradients distributions' influence on MRI signals. Approach: We employed the Finite Perturber Method (FPM) to calculate intravoxel magnetic gradients and MonteCarlo simulations to simulate the spins diffusion using a MGSE sequence. Results: Our findings demonstrate up to 2.5 % signal variations when incorporating Internal Gradient Distribution terms, offering insights into signal behavior with varying microstructure parameters. Impact: The complementary findings of addressing non-invasive tissue-microstructure changes based on probing internal gradients paves the way for early pathological detection. This empowers clinicians to in-depth investigations, transforming our approach to diagnostics and enhancing healthcare outcomes.