Thiele Kobus1, Jack Van Asten1, Alan Wright1, Arend Heerschap1, Tom Scheenen1
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands
PRESS and semi-LASER based 1H MRSI was performed in 17 patients with highly aggressive prostate cancer. The maximum choline plus creatine over citrate ratio and the maximum choline over creatine ratio were determined. Both metabolite ratios were very abnormal in all patients. The absence of frequency-selective lipid suppression in the semi-LASER sequence enables detection of metabolites in a broader frequency range. This enabled detection of an unassigned peak at 2.05 ppm. Although the identity of this resonance remains unknown, it was excluded that this resonance belonged to either spermine, glutamate or glutamine.