1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands; 2Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen, Germany; 3Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
We assessed T1 relaxation times of 31P metabolites in the human prostate and evaluated the nuclear Overhauser effect (NOE) as signal enhancement strategy for 31P MRSI of the prostate at 7T. T1 relaxation times were found to be relatively long compared to other human tissues at 7T. To obtain a 3D 31P MRSI dataset within a clinically acceptable measurement time (TR ≤ 1.5s) with optimal SNR per unit time, a strongly reduced flip angle (≤ 45) is required. Signal enhancement by irradiating the water resonance to obtain NOE was successful, yielding up to 42% more signal for PE.