Phantom Study on the Dependency of the MRI Phase Contrast on the Underlying Micro Structure

Jan Sedlacik¹, Ferdinand Schweser²

Signal-phase contrast in gradient echo imaging delineates anatomic brain structures in great detail. While the phase contrast in the deep gray matter nuclei has been attributed to iron, the origin of the phase contrast between gray and white matter is not yet fully understood. He and Yablonskiy proposed a Lorentzian cylinder approximation which predicts phase effects due to the (sub-)cellular diffusion anisotropy in the vicinity of myelin bundles. Liu et al. found considerable anisotropy of the magnetic susceptibility of myelin-lipids. Purpose of this work was to investigate both phenomena more closely using phantom experiments with well-defined magnetic and structural properties.