What does PET stand for in medical imaging?

What does PET stand for in medical imaging?

• A. Positron emission tomography
• B. Positron emissions tomography
• C. Proton emission tomography
• D. Photon emission tomography

Answer: (B)

Positron Emission Tomography describes a medical imaging method that uses a radiotracer which emits positrons. When a positron encounters a nearby electron, they annihilate to produce two 511-keV photons that travel in opposite directions and are detected by the scanner to form functional images of tissue. The term “emission” is singular because it refers to the emission event of the positron per decay, not a plural process, and “tomography” means imaging by slices to create cross-sectional pictures. The other phrasing isn’t correct: using “emissions” adds an unnecessary plural form, “proton emission tomography” would imply protons are involved instead of positrons, and “photon emission tomography” omits the specific mechanism of positron emission and annihilation that defines PET.

Positron Emission Tomography describes a medical imaging method that uses a radiotracer which emits positrons. When a positron encounters a nearby electron, they annihilate to produce two 511-keV photons that travel in opposite directions and are detected by the scanner to form functional images of tissue. The term “emission” is singular because it refers to the emission event of the positron per decay, not a plural process, and “tomography” means imaging by slices to create cross-sectional pictures. The other phrasing isn’t correct: using “emissions” adds an unnecessary plural form, “proton emission tomography” would imply protons are involved instead of positrons, and “photon emission tomography” omits the specific mechanism of positron emission and annihilation that defines PET.