A computer uses the data gathered by the detectors to create multi-dimensional (normally 3-dimensional volumetric or 4-dimensional time-varying) images that show the distribution of the radiotracer in the brain following the time.

Especially useful are a wide array of ligands used to map different aspects of neurotransmitter activity, with by far the most commonly used PET tracer being a labeled form of glucose, such as fluorodeoxyglucose (18F).

[2] The greatest benefit of PET scanning is that different compounds can show flow and oxygen, and glucose metabolism in the tissues of the working brain.

PET scanning is also useful in PET-guided stereotactic surgery and radiosurgery for treatment of intracranial tumors, arteriovenous malformations and other surgically treatable conditions.

PET is probably most useful in early cases of certain dementias (with classic examples being Alzheimer's disease and Pick's disease) where the early damage is too diffuse and makes too little difference in brain volume and gross structure to change CT and standard MRI images enough to be able to reliably differentiate it from the "normal" range of cortical atrophy which occurs with aging (in many but not all) persons, and which does not cause clinical dementia.

[11C]PMP (N-[11C]methylpiperidin-4-yl propionate) is a novel radiopharmaceutical used in PET imaging to determine the activity of the acetylcholinergic neurotransmitter system by acting as a substrate for acetylcholinesterase.

[12] Avid Radiopharmaceuticals has developed and commercialized a compound called florbetapir that uses the longer-lasting radionuclide fluorine-18 to detect amyloid plaques using PET scans.

[13] In 2019 Catana et al.[14] published an overview article about the "Development of Dedicated Brain PET Imaging Devices: Recent Advances and Future Perspectives".