Gregory T. Baxter1, Lawrence R. Frank1
1Radiology, UCSD, La Jolla, CA, United States
Sen and Basser developed a theoretical model for diffusion in white matter in the brain in the long-time limit. Their model represents white matter fascicles as coated cylinders in periodic arrays, with distinct axonal core, myelin sheath, and surrounding medium. We implement this white matter model in a Monte Carlo diffusion simulator to find results in the context of DTI. Anisotropy calculated from numerical simulations matches the theoretical model in the long-time limit, but anisotropy is significantly understated when diffusion time is short. Anisotropy is also sensitive to the concentration of spins in the myelin sheath.