Clinical application of BASING and spectral/spatial water and lipid suppression pulses for prostate cancer staging and localization by in vivo 3D H-1magnetic resonance spectroscopic imaging

In previous in situ point-resolved spectroscopy (PRESS) three-dimensional ( 3D) H-1 magnetic resonance (MR) spectroscopic imaging studies, it has been demonstrated that the ratio of prostatic metabolites can noninvasively disc riminate prostate cancer from surrounding normal tissue. However, in these studies, conventional chemical shift selective suppression (CHESS) and shor t-time inversion recovery (STIR) techniques often resulted in inadequate wa ter and lipid suppression. To improve suppression and spatial coverage, the newly developed T-1 insensitive dual band selective inversion with gradien t dephasing (BASING) Bandstop Filter and dual phase-compensating spectral/s patial spin-echo pulses have been implemented in a clinical setting. In pha ntom studies, no change in metabolic profiles was observed with application of either BASING or spectral/spatial pulses. In a study of 17 prostate can cer patients, the use of either BASING or spectral/spatial pulses allowed f or suppression of water (BASING 99.80 +/- 0.14% and spectral/spatial 99.73 +/- 0.47%) and lipid (BASING 98.56 +/- 1.03% and spectral/spatial 98.44 +/- 1.90%) without a significant difference in the prostatic metabolite ratios . Spectral/spatial suppression has the added advantage of reducing the chem ical shift dependence of the PRESS volume, but optimal performance requires high-speed gradients with negligible eddy current effects. BASING suppress ion is less reliant on accurate pulse and gradient timings and can be imple mented easily with no loss in performance on clinical MR scanners with conv entional gradients. Magn Reson Med 43:17-22, 2000, (C) 2000 Wiley-Liss, Inc .