Selective excitation localized by the Bloch-Siegert shift and a B1+ gradient.

ABSTRACT:

Purpose

To perform B1+$$ {B}_1^{+} $$ -selective excitation using the Bloch-Siegert shift for spatial localization.

Theory and methods

A B1+$$ {B}_1^{+} $$ -selective excitation is produced by an radiofrequency (RF) pulse consisting of two summed component pulses: an off-resonant pulse that induces a B1+$$ {B}_1^{+} $$ -dependent Bloch-Siegert frequency shift and a frequency-selective excitation pulse. The passband of the pulse can be tailored by adjusting the frequency content of the frequency-selective pulse, as in conventional B0$$ {B}_0 $$ gradient-localized excitation. Fine magnetization profile control is achieved by using the Shinnar-Le Roux algorithm to design the frequency-selective excitation pulse. Simulations analyzed the pulses' robustness to off-resonance, thei

SUBMITTER: Martin JB 

PROVIDER: S-EPMC9246893 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature