EINFLUSS TRANSIENTER VORGÄNGE IM DYNAMISCHEN KONTRASTMITTELVERSTÄRKTEN MAGNETRESONANZ IMAGING

S l i M M A K V l'hc purposc of this work was lo assess thc d \namic inllucncc of contrast agent adminislralion on iho signal mtcnsi ty in dynamic contrast enhanced magnetic resonance iinaging (DCE-MRI). DCE-MRi is uscil In r ilclermination of phannacokinetic parameters öl tinnors. fhcreby quantitative characterization of the Enhancement curves requires a complete appreciation of u iKle rUing physiological and MR physics mechanisms. l l o w c N c r , (he formulas applicd in quantitative analyses are derived froin steady state (SS) conditions. Using the partilion method the signal inlensity was calculated for the fü l l evolving inagnetization for different parameter sethngs and contrast courses. Performed simulations have been \ alidated by phantom measurements of the iransicnt response ai the beginning of data acquisition. C'ompanson of signal intensities calculated by SS Solutions and the partilion method showed a difference up t o 10° o especially at fast injections of contrast media. Knowledge of the signal behavior diiring contrast agent administration shows that analyses of measured signal intensities vvith SS Solutions are affected with extra errors additional to measuring errors.