Single-voxel oversampled J-resolved spectroscopy of in vivo human prostate tissue.

Abstract

Single-voxel J-resolved spectroscopy with oversampling in the F1 dimension was used to obtain water unsuppressed 1H spectra of in situ human prostate tissue in 40 previously untreated prostate cancer patients. Based on T2-weighted MRI and previous biopsy information, voxels were placed in regions of benign or malignant peripheral zone tissue, or in regions of predominantly glandular or stromal benign prostatic hyperplasia (BPH) within the central gland. The addition of a second J-resolved dimension allowed for the observation of the J-modulation of citrate, as well as the resolution of polyamines from overlapping choline and creatine signals. Regions of healthy peripheral zone tissue and glandular BPH all demonstrated high levels of citrate and polyamines, with consistent coupling and J-modulation patterns. Conversely, regions of malignant peripheral zone tissue and stromal BPH demonstrated low levels of citrate and polyamines consistent with prior in vivo and ex vivo studies. Moreover, water T2 relaxation times determined for healthy peripheral zone tissue (mean 128 +/- 15.2 msec) were significantly different than for malignant peripheral zone tissue (mean 88.0 +/- 14.2 msec, P = 0.005), as well as for predominantly glandular (mean 92.4 +/- 12.2 msec, P = 0.009) and stromal BPH (mean 70.9 +/- 12.1 msec, P = 0.003). This preliminary study demonstrates that J-resolved spectroscopy of the in situ prostate can be acquired, and the information obtained from the second spectral dimension can provide additional physiologic information from human prostate tissue in a reasonable amount of time (< 10 min).