PET scanning

The abbreviation for positron emission tomography, a diagnostic technique based on the detection of positrons (a type of subatomic particle) that are emitted by radioactively labelled substances introduced into the body. PET scanning produces 3-dimensional images of the metabolic and chemical activity of tissues. Substances used in biochemical processes in the body are labelled with radioisotopes and then injected into the bloodstream. The substances are taken up in greater concentrations by tissues that are more metabolically active. The substances emit positrons, which release photons that are detected by the scanner. PET scans are used to detect brain tumours, locate epileptic activity within the brain, and examine brain function.


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