Theoretical study of the free water elimination model

Publication Type:

Conference Abstract

Source:

ISMRM 23th Annual Meeting, Toronto, Ontario, Canada, Volume 23, p.2757 (2015)

Abstract:

Partial volume effects caused by cerebrospinal fluid are an important issue in diffusion MRI. In this work, we study the free water elimination model by analyzing the Cramér-Rao lower bound (CRLB) of its parameters. We show that through optimizing the acquisition protocol by minimizing the trace of the CRLB, a significant gain in the precision of the parameter estimation can be achieved. Moreover, further analysis indicates that regularization and/or constraints are necessary for parameter estimation from voxels with large CSF fractions and/or low FA values. These theoretical findings are confirmed by both simulation and real data experiments.