What is a primary source of radiation exposure to a technologist during PET imaging?

In the context of PET imaging, a primary source of radiation exposure to a technologist is Compton scatter from the patient. During a PET scan, positrons emitted from a radiopharmaceutical interact with electrons in the patient's body, resulting in the emission of gamma rays when the positrons annihilate. These gamma rays can undergo Compton scattering, which involves the deflection of the gamma rays as they interact with matter, such as the tissues of the patient.

Technologists may be exposed to these scattered gamma rays, which can lead to increased radiation dose in the work environment. Proper shielding and techniques are essential in minimizing this exposure. While other radiation sources can be present, the scattering of gamma rays from the patient's tissues is particularly relevant to the technologist's occupational exposure during PET imaging procedures.