Designing 3D selective adiabatic radiofrequency pulses with single and parallel transmission.

ABSTRACT:

Purpose

To introduce a method of designing single and parallel transmit (pTx) 3D adiabatic π pulses for inverting and refocusing spins that are insensitive to transmit B₁ ( B1+) inhomogeneity.

Theory and methods

A 3D adiabatic pulse is created by replacing each piece-wise constant element (or sub-pulse) of an adiabatic full passage (AFP) by a 2D selective pulse. In this study, the parent AFP is an HS1 and each sub-pulse is a 2D pulse derived from a jinc function designed using a spiral k-trajectory. Spatial selectivity in the third direction is achieved by blipping the slab-selective gradient between sub-pulses, yielding a rectangular slab profile identical to that of the parent AFP. The slew-rate limited sub-pulse can be undersampled utilizing pTx, thus shortenin

SUBMITTER: Jang A 

PROVIDER: S-EPMC5682242 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature