[Modern nuclear medical diagnosis as applied pathophysiology. Basis and outlook]

In their capacity as "image-assisted functional diagnostics", methods of nuclear medicine link morphological patterns of radiology with clinical presentation. Based on pathophysiology they supply an insight into both global and regional parameters, present as basal values or as reserves. Both, single photon emission computed tomography (SPECT) or highly defined positron ECT (PET), enabled computer-assisted topographical overlay and thus an exact comparative evaluation of regional function versus morphology. In addition, PET gives access to a true physiological, absolute quantification employing process specific, carrier-free substrates. Novel tracers (markers of metabolism or perfusion, receptors or transmitter substances, monoclonal antibodies), an intraluminal transport model and the concept of buffer or working reserves aim at conducting early diagnosis, determination of disease severity and parameters that are relevant for therapy, on a level that is pathophysiologically oriented.