Benoit Scherrer1, Simon K. Warfield2
1Department of Radiology, Computational
Radiology Laboratory , Boston, MA, United States; 2Department of Radiology,
Computational Radiology Laboratory, Boston, MA, United States
We
show that multi-tensor models cannot be properly estimated with a
single-shell HARDI acquisition because the fitting procedure admits a
infinite number of solutions, melding the estimated tensors eigenvalues and
the partial volume fractions. As a result, a uniform fiber bundle across its
entire length may appear to grow and shrink as it passes through voxels and
experiences different partial volume effects. Only the use of multiple-shell
HARDI acquisitions allows the system of equations to be better determined. We
provide numerical experiments to explore the optimal acquisition scheme for
multi-tensor imaging.