Extended RF shimming: Sequence-level parallel transmission optimization applied to steady-state free precession MRI of the heart.

ABSTRACT: Cardiac magnetic resonance imaging (MRI) at high field presents challenges because of the high specific absorption rate and significant transmit field (B1+ ) inhomogeneities. Parallel transmission MRI offers the ability to correct for both issues at the level of individual radiofrequency (RF) pulses, but must operate within strict hardware and safety constraints. The constraints are themselves affected by sequence parameters, such as the RF pulse duration and TR, meaning that an overall optimal operating point exists for a given sequence. This work seeks to obtain optimal performance by performing a 'sequence-level' optimization in which pulse sequence parameters are included as part of an RF shimming calculation. The method is applied to balanced steady-state free precession cardiac MRI w

SUBMITTER: Beqiri A 

PROVIDER: S-EPMC5484304 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature