Optimized quantification of spin relaxation times in the hybrid state.

ABSTRACT:

Purpose

The optimization and analysis of spin ensemble trajectories in the hybrid state-a state in which the direction of the magnetization adiabatically follows the steady state while the magnitude remains in a transient state.

Methods

Numerical optimizations were performed to find spin ensemble trajectories that minimize the Cramér-Rao bound for T 1 -encoding, T 2 -encoding, and their weighted sum, respectively, followed by a comparison between the Cramér-Rao bounds obtained with our optimized spin-trajectories, Look-Locker sequences, and multi-spin-echo methods. Finally, we experimentally tested our optimized spin trajectories with in vivo scans of the human brain.

Results

After a nonrecurring inversion segment on the southern half of the Bloch sphere, all optimi

SUBMITTER: Asslander J 

PROVIDER: S-EPMC7301573 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature