The objective of this study was to demonstrate the feasibility of 3D
proton MR spectroscopic imaging (MRSI) of the prostate using a standard spine instead of a dedicated endorectal coil at 1.5 T. Twenty-eight patients (25 with biopsy proven
prostate cancers and three patients with a benign prostate
hyperplasia) were examined. MRI and MRSI were conducted with commercial array surface coils at 1.5 T. Ratios of
choline (Cho),
creatine (Cr) and
citrate (Ci) were calculated for tumour, central and peripheral zone retrospectively, based on axial T2 weighed MR images and histology reports.
Prostate cancer was characterized by significantly elevated (Cho+Cr)/Ci ratio compared with non-tumourous prostate tissue. The quality of all
proton MR spectra was considered to be good or acceptable in 17/28 patients (61%) and poor in 11/28 (39%) examinations. In 20/25 patients with proven
malignancy (80%), MRSI was considered to be helpful for the detection of
prostate cancer. In 4/25 patients with proven
malignancy (16%) who underwent seed implantation,
radiotherapy or
hormone deprivation before MR examination spectroscopy was of poor and non-diagnostic quality. MRSI of the prostate is feasible within clinical routine using the spine array surface coil at 1.5 T. It can consequently be applied to patients even with
contraindications for endorectal coils. However, spectral quality and signal-to-noise ratio is clearly inferior to 3D MRSI examinations with endorectal coils.