This nuclear imaging technique combines position emission tomography (PET) and computed tomography (CT) into one machine. A PET/CT scan reveals information about both the structure and function of cells and tissues in the body during a single imaging session.
During a PET/CT scan, the patient is first injected with a glucose (sugar) solution that contains a very small amount of radioactive material. The substance is absorbed by the organs or tissues being examined. The patient rests on a table that slides into a large tunnel-shaped scanner. The PET/CT scanner is then able to “see” damaged or cancerous cells where the glucose is being absorbed (cancer cells often use more glucose than normal cells) and the rate at which the tumor is using the glucose, which may help determine the tumor grade. The procedure is painless and varies in length, depending on the part of the body being evaluated.
By combining information about the body’s anatomy and metabolic function, a PET/CT scan provides a more detailed picture of cancerous tissues than either test does on its own. The images are captured in a single scan.
Most oncologists perform a CT scan and/or a bone scan prior to ordering a PET/CT scan.