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Chemistry: Challenges and Solutions

How a PET Scan Works (animation)

To receive a PET scan, the patient ingests an unstable isotope. Inside the body, the isotope emits a positron, which collides with an electron and they annihilate, creating two photons shoot off in opposite directions exactly 180 apart from one another. The scanner detects the two photons and can map their point of origin to create an image of places where the isotope was most concentrated.

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Chemistry: Challenges and Solutions


Produced by the Harvard-Smithsonian Center for Astrophysics. 2014.
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