T2* Measurement bias due to concomitant gradient fields.

ABSTRACT:

Purpose

To demonstrate that concomitant magnetic fields can cause significant spatially dependent biases in T2* relaxometry measurements with implications for clinical applications such as BOLD and dynamic susceptibility contrast-enhanced MRI.

Theory and methods

After developing a theoretical framework for intravoxel dephasing and signal loss from concomitant magnetic fields, this framework and the effect of concomitant fields on T2* are validated with phantom experiments and numerical simulation. In lower leg and renal T2* mapping, we quantify measurement bias for imaging protocols with high gradient amplitude multiecho readouts, comparable to those used in clinical applications.

Results

Concordance between phantom experiment and numerical simulation validate the the

SUBMITTER: Hofstetter LW 

PROVIDER: S-EPMC5266676 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature