ARRT Nuclear Medicine Practice Test 2026 – The Complete All-in-One Guide to Exam Success!

After the administration of F-18 FDG for PET scans, instructing patients to rest quietly in a waiting area until the scan begins is crucial for ensuring the accuracy of the imaging results. The reason for this instruction lies in the nature of the positron emission tomography (PET) scans.

F-18 FDG is a radiopharmaceutical that mimics glucose in the body and is taken up by active tissues, particularly those that are metabolically active like tumors. By having patients remain calm and still, you help minimize muscle activity that could lead to increased FDG uptake in muscles rather than in the areas of interest (such as tumors). Movement or activity can result in artifacts or less clear images, as it might lead to an increase in background activity in the scan.

Therefore, allowing the radiotracer time to distribute and be absorbed by the tissues of interest while the patient is at rest contributes to obtaining high-quality images that more accurately reflect the metabolic processes occurring in the body.