Abstract: In the pharmaceutical industry, there is currently increasing interest in noninvasive functional imaging techniques as potential early indicators of drug effects in patients. PET allows one to monitor absolute concentrations of radiolabeled drugs and metabolites, or of ligands to specific receptors, in tissues, and to visualize their distribution three-dimensionally. MRS is capable of monitoring metabolic conversions in vivo without labeling. DCE-MRI shows the distribution of small-molecular, hydrophilic weight contrast agents between blood plasma and interstitial space in tissue in real time and can be used to detect effects of antivascular or anti-angiogenic compounds.

Key words: PET, in vivo, MRS, DCE-MRI