Identify a common imaging procedure that employs PET radiopharmaceuticals.

Fluorodeoxyglucose (FDG) is a radiopharmaceutical commonly used in positron emission tomography (PET) scans. PET scans are specialized imaging techniques that visualize metabolic processes in the body. FDG is a glucose analog that is taken up by cells, particularly those that are metabolically active, such as cancer cells. When FDG is administered and subsequently decays, it emits positrons which can be detected to create detailed images of how glucose is utilized in various tissues.

This is particularly useful in oncology, as cancerous tissues often demonstrate increased glucose metabolism, allowing for the identification and staging of tumors. Additionally, PET imaging can assist in monitoring treatment efficacy and detecting recurrences. Other imaging modalities listed, such as MRI, X-ray, and ultrasound, do not utilize PET radiopharmaceuticals and function based on different principles, making them less relevant to the context of PET imaging.