Positron emission tomography (PET) is a diagnostic imaging technique of nuclear medicine that is used preferentially for clinical purposes in oncology, cardiology and  neurology.

It is a a non-invasive method through which functional images are taken after the administration to the patient of specific radiopharmaceuticals that comprise molecules (sugars, amino acids, metabolic precursors, hormones, etc) marked with positron emission radioactive isotopes.

The aim of this technique is to study biological functions like the metabolic activity, blood flow, cell viability, cell proliferation, the transport of amino acids, the density and occupation of neuro-receptors, etc.

This technique has a high capacity to distinguish benignancy from malignancy in primary lesions, it can establish the extension and scope of a malign tumor (staging), the detection of recidivations and the response to treatment as well as the diagnosis of diseases present without structural change that only show biochemical changes, as is the case of psychiatric diseases. Finally, it can identify the viable myocardic tissue and suitably select the patients who could benefit from myocardic revascularization procedures.

The equipment required for a PET exploration comprises:

• PET Gamma camera: for the detection and reproduction of the image after administration to the patient, intravenously, of the radiopharmaceutical. The radionuclides emit positrons during their passage through the organism (particles with positive charge) that collide with negatively charged particles, giving rise to two high-energy photons in opposing directions (180º angle). The positron camera detects these two photons simultaneously (detection by coincidence) to create images that we visualize in the tomograph.

• High-tech computer equipment: allows storage of data, reconstruction of the image and its visualization.