Mechanical Stiffness and Anisotropy Measured by MR Elastography during Brain Development in the Minipig

The relationship between brain development and mechanical properties of brain tissue is important but remains incompletely understood. Here we use data from magnetic resonance elastography (MRE) and diffusion tensor imaging (DTI) to estimate anisotropic mechanical properties in six female Yucatan minipigs at ages from 3 to 6 months with a transversely- isotropic nonlinear inversion (TI-NLI) algorithm. Our results show that white matter is more dissipative and anisotropic than gray matter, and reveal effects of brain development on brain stiffness and structural anisotropy. Changes in brain mechanical properties may be a fundamental biophysical signature of brain development.