Data acquisition and postprocessing strategies for fast quantitative sodium imaging

An efficient scheme for quantitatively mapping the threethe total data acquisition time (DAT). To compensate for T2 dimensional distribution of the sodium ion in vivo using magnetic signal modulation, TE must be much shorter than the values resonance imaging is described. To make the methodology totally typically used in proton MRI studies. Use of TE values above 1 quantitative, the data acquisition scheme is performed with very short ms, for example, can lead to significant biases in the measured echo times and negligible T1 saturation. Removal of signal variation tissue sodium concentration (TSC) owing to the sizable changes due to imperfect radiofrequency (RF) response is accomplished using in T2 that arise with the changes in the compartmentalization of RF inhomogeneity maps acquired during each study. The high effithe sodium ion [10]. ciency of the k-space trajectories allows the entire data collection To obtain short TE values, the length of the RF pulse and the process to be performed in under 10 min. The theory underlying the delay between excitation and data acquisition must be minimized. data collection and processing scheme is described along with representative examples acquired at 1.5 and 3.0 T. q 1997 John Wiley & In practice, this requires the use of nonselective RF pulses and Sons, Inc. Int J Imaging Syst Technol, 8, 544–550, 1997 three-dimensional (3D) data acquisition schemes. To keep TE as short as possible, the k-space trajectory must begin at the origin of