Published online by Cambridge University Press: 10 March 2009
Positron emission tomography (PET) is a new nuclear medicine technique that has recently entered the clinical realm of medicine. Although it is a technique that can be utilized for assessment of biochemical and physiological parameters of any organ in the body, it has particular utility in the investigation of the brain. PET poses unique advantages over previous imaging devices. For the first time, it is feasible to investigate directly various biological parameters of the brain in a noninvasive way. PET allows for investigating the functional, biochemical, physiological, and pharmacological characteristics of various areas within the brains of normal and psychiatric or neurological patients. Although it has already started to give promising results, it is too new a technique to obtain an accurate appraisal of its true potentials. This is a problem that seems always to surface when one tries to evaluate the utility of a new technique in a new area of research. The problem is accentuated in the case of PET where there is no other technique available with which to compare results. This paper will discuss the basic principles of PET, its relationship to other existing imaging devices, and the issues to be considered when making a technological assessment of positron emission tomography.