Comparison of inversion recovery preparation schemes for lipid suppression in 1 H MRSI of human brain

To reduce contamination from subcutaneous lipid regions in MR spectroscopic imaging (MRSI) of whole brain, lipid signals are often suppressed using T 1 nulling methods. If a range of lipid T 1 values is present, the suppression efficiency will be improved using multiple inversion recovery (MIR) preparation. This study compared single IR (SIR) and double IR (DIR) applied with a volumetric MRSI sequence at 1.5 T based on experimental measurement of lipid T 1 and T 2 relaxation rates. At short and medium echo times (TEs), an approximately 28–47% improvement in lipid suppression was achieved with DIR compared to SIR. However, it also led to a loss of 37–43% in signal‐to‐noise ratio (SNR) for metabolites. Thus, SIR appears to be the better choice for suppressing lipid signals and maintaining metabolite sensitivity. Magn Reson Med 49:903–908, 2003. © 2003 Wiley‐Liss, Inc.