PET scan

American  

[pet skan] / ˈpɛt ˌskæn /

noun

Computers, Medicine/Medical.

1. an image obtained by positron emission tomography, using a PET scanner.

2. an examination performed with a PET scanner.

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PET scan Scientific  

/ pĕt /

1. Short for positron emission tomography scan. A cross-sectional image of a metabolic process in a human or animal body produced by positron emission tomography.

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PET scan Cultural  

1. Acronym for p ositron e mission t omography, a medical test that is especially useful in showing how tissue or an organ is functioning, as opposed to just showing structure. In a PET scan, radioactive atoms are introduced into the body, where their chemical behavior is exactly the same as similar nonradioactive atoms. The positrons emitted when these nuclei decay collide with electrons in surrounding tissue, producing gamma rays that can then be detected by instruments outside the body.

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Discover More

A PET scan can show the blood flow through the brain, areas of high metabolic activity that indicate potential tumors, as well as areas of damaged heart tissue.

Etymology

Origin of PET scan

First recorded in 1975–80; PET ( def. ) + scan ( def. )

Example Sentences

I spent the next several days trotting to back-to-back appointments for procedures and tests, including a breathing test, a PET scan and a lung biopsy.

From The Wall Street Journal • Feb. 13, 2026

All the volunteers will have the current gold-standard tests for Alzheimer's which involve a specialised brain PET scan using a radioactive tracer, or a lumbar puncture to remove a sample of cerebrospinal fluid.

From BBC • Jan. 18, 2026

To observe brain changes, researchers used a specialized PET scan and tracer that makes cholinergic reserves visible, allowing them to measure activity before and after the training period.

From Science Daily • Oct. 29, 2025

Other questioners wondered if Galleri’s performance had been inflated, because the study followed up an initial positive blood test with a full-body PET scan.

From Barron's • Oct. 22, 2025

The chemical is also a radioactive isotope, which means it can be visualized using a PET scan.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel