A realistic in-silico brain phantom for magnetic susceptibility-separation algorithm validation

Motivation: Positive and negative susceptibility mapping is an emerging method that can benefit from the availability of validation tools. Goal(s): To create an in-silico brain phantom for positive and negative susceptibility and to assess the impact of white matter’s anisotropic susceptibility on susceptibility-separation techniques. Approach: Simulate positive and negative susceptibility maps and gradient-echo data with/without anisotropy. Process simulated data with different susceptibility-separation algorithms. Compare the results with the ground truth. Results: The error associated with negative susceptibility measurements is ~9% greater when anisotropy effects are present in the phantom, suggesting that a new susceptibility-separation algorithm that considers myelin’s anisotropic susceptibility may be warranted. Impact: Researchers developing novel magnetic susceptibility-separation methods can use our proposed phantom to test different aspects of their technique, ranging from the biophysical model to image processing methods and imaging protocol parameters.