Robust 3D Bloch-Siegert based B1+ mapping using multi-echo general linear modeling.

ABSTRACT:

Purpose

Quantitative MRI applications, such as mapping the T₁ time of tissue, puts high demands on the accuracy and precision of transmit field ( B1+ ) estimation. A candidate approach to satisfy these requirements exploits the difference in phase induced by the Bloch-Siegert frequency shift (BSS) of 2 acquisitions with opposite off-resonance frequency radiofrequency pulses. Interleaving these radiofrequency pulses ensures robustness to motion and scanner drifts; however, here we demonstrate that doing so also introduces a bias in the B1+ estimates.

Theory and methods

It is shown here by means of simulation and experiments that the amplitude of the error depends on MR pulse sequence parameters, such as repetition time and radiofrequency spoiling increment, but mor

SUBMITTER: Corbin N 

PROVIDER: S-EPMC6771691 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature