[Checklist for understanding magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS)].

Overview on informations which are necessary to interpret MRI and MRS. The approach is related rather to application than it is a physical one. The central steps in comprehending MR are presented, e.g. frequency decomposition in order to obtain local information with MRI or chemical information with MRS, the spin echo in order to differentiate instrumental dephasation from dephasation by molecular interference, perfusion in MRI, and the components of sensitivity in measuring different nuclei etc. The report terminology is based on the description of grey scale pictures, but one has to consider that the information is not one-dimensional but multiparametric. Therefore new terms have to be developed, a problem similar to that of describing scintigraphic time sequences in nuclear medicine.