Fiber Density Estimation from Single Q-Shell DWI by Tensor Divergence

Marco Reisert¹, Elias Kellner¹, Henrik Skibbe¹, Valerij Kiselev¹

Diffusion-sensitized magnetic resonance imaging provides information about the nerve fiber bundle geometry of the human brain. While the inference of the underlying fiber bundle orientation only requires single q-shell measurements, the absolute determination of their volume fractions is much more challenging. This work uses a conservation law for fiber orientation densities that can infer the absolute fraction. In this study we show by simulations on a pseudo ground truth phantom that for complex, brain-like geometries the method is able to infer the densities correctly. In-vivo results with 81 healthy volunteers scanned with a clinical feasible protocol are plausible and consistent.