Papers Published

1. EW Hsu, SB Reeder, JR MacFall, Single-shot, variable flip-angle slice-selective excitation with four gradient-modulated adiabatic half-passage segments., Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine, UNITED STATES, vol. 40 no. 2 (August, 1998), pp. 334-40 .
   (last updated on 2003/08/22)

   Abstract:
   Adiabatic pulses, although useful in generating uniform spin nutation in the presence of inhomogeneous B1 fields, are limited for NMR imaging applications due to the lack of slice-selective excitation capability. Selective excitation techniques using gradient modulation have been introduced; however, present methods require either a minimum of two excitations or eight adiabatic segments. Here, a scheme is presented that allows single-shot, arbitrary flip-angle, and slice-selective excitation with only four adiabatic half-passage segments. The technique is demonstrated via computer simulation and experimental tests on a phantom. Furthermore, issues associated with the implementation of these gradient-modulated adiabatic pulses are discussed.

   Keywords:
   Computer Simulation • Fourier Analysis • Humans • Magnetic Resonance Imaging* • Magnetic Resonance Spectroscopy* • Phantoms, Imaging • Sensitivity and Specificity