[Positron emission tomography: foundations and applications].

Positron emission tomography (PET) is a non-invasive biomedical imaging technique whereby the distribution of biological tracer molecules, labelled by positron emitting isotopes, in the living body can be studied quantitatively. As theoretically an metabolically active molecule can be labelled, the technique is applicable to the measurement of any biochemical or physiological process in proper anatomical context. The introduction of PET has revolutionised the exploration of normal physiological functions. With the help of technique, among others, anatomical structures underlying mental functions can be localised in the human brain, the receptor architecture of the nervous system can be mapped, or the kinetics of pharmacons can be properly measured and modelled. In the clinical practice, PET has proven to be a uniquely useful diagnostic technique in neurology, psychiatry, cardiology, and oncology in establishing primary diagnosis and differential diagnosis, designing therapeutic interventions as well as assessing their efficacy. Hungary's and Central European region's first PET center has been established at the University Medical School in Debrecen.