A diffusion model-free framework with echo time dependence for free-water elimination and brain tissue microstructure characterization.

ABSTRACT:

Purpose

The compartmental nature of brain tissue microstructure is typically studied by diffusion MRI, MR relaxometry or their correlation. Diffusion MRI relies on signal representations or biophysical models, while MR relaxometry and correlation studies are based on regularized inverse Laplace transforms (ILTs). Here we introduce a general framework for characterizing microstructure that does not depend on diffusion modeling and replaces ill-posed ILTs with blind source separation (BSS). This framework yields proton density, relaxation times, volume fractions, and signal disentanglement, allowing for separation of the free-water component.

Theory and methods

Diffusion experiments repeated for several different echo times, contain entangled diffusion and relaxation compartme

SUBMITTER: Molina-Romero M 

PROVIDER: S-EPMC6790970 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature