The effects of basis sets on magnetic resonance spectroscopy quantification for stock PRESS sequences, a simulation study
Karl Landheer1, Martin Gajdošík1, and Christoph Juchem1,2
1Biomedical Engineering, Columbia University, New York City, NY, United States, 2Radiology, Columbia University, New York City, NY, United States
The effect that using a realistic
basis set (i.e., simulation which involves proper shaped RF pulses and timings)
versus a basis set at the same echo but different exact details is investigated
here via simulation with realistic PRESS spectra.
Figure 2: The synthesized
GE spectra at the three different echo times along with the fits for the four
different basis sets. The synthesized spectra are given in black, the fit in red
and the residual in grey. Perfect fits can be observed with the GE basis, as
expected, since these particular spectra were synthesized from the GE basis, while
non-perfect fits were obtained with the other three basis sets. Similar results
were obtained for the synthesized Philips and Siemens spectra (results not
shown).
Figure 1: The synthesized
spectra for TE = 30 ms, A, TE = 80 ms, B, and TE = 144 ms, C, across the three
different vendor implementations of PRESS with blue depicting the Siemens
implementation, red depicting the GE implementation and black depicting the
Philips implementation. Spectra have been normalized to account for differences
in voxel profile due to different pulses (i.e., different transition widths).