Clinical magnetic resonance spectroscopy: A critical evaluation

The present status of magnetic resonance spectroscopy (MRS) in the clinical radiology setting is discussed critically. The number of groups reporting clinical MRS results has increased, indicating the feasibility of performing localized MRS studies on current 1.5 T whole body MR imagers. However the lack of high quality radiofrequency (RF) coils for MRS and proven user-independent methods for the analysis of spectral data is still hampering further development. At present there is no consensus as to the optimal localization scheme which should be employed for phosphorus (³¹P) MRS. For proton MRS the stimulated echo sequence is gaining wide acceptance. The minimum voxel sizes achievable for proton and³¹P MRS in the brain are calculated to be 2 and 30 cm³, respectively. The recent results obtained with proton decoupling for³¹P clearly demonstrate that there is a great deal of improvement possible in the quality of localized³¹P spectra at 1.5 T. Both the instrument manufacturers and researchers in the field face important challenges in translating methods which have proven feasibility in the research environment into routine clinical protocols.