Positron Emission Tomography
Positron Emission Tomography (PET) and Computerized Tomography (CT) are both standard imaging tools that allow physicians to pinpoint the location of cancer within the body before making treatment recommendations.
The highly sensitive PET scan detects the metabolic signal of actively growing cancer cells in the body and the CT scan provides a detailed picture of the internal anatomy that reveals the location, size and shape of abnormal cancerous growths.
Alone, each imaging test has particular benefits and limitations but when the results of PET and CT scans are “fused” together, the combined image provides complete information on cancer location and metabolism.
The bottom line is that you can have both scans – PET and CT – done at the same time.
In one continuous full-body scan (usually about 30 minutes), PET captures images of miniscule changes in the body’s metabolism caused by the growth of abnormal cells, while CT images simultaneously allow physicians to pinpoint the exact location, size and shape of the diseased tissue or tumor. Essentially, small lesions or tumors are detected with PET and then precisely located with CT.
While a CT scan provides anatomical detail (size and location of the tumor, mass, etc.), a PET scan provides metabolic detail (cellular activity of the tumor, mass, etc.). Combined PET/CT is more accurate than PET and CT alone!
Preparation and Special Instructions
Instructions will be given to you at the time of scheduling, whether by our office or by your physician. For most PET procedures, you will be asked to take in only water for 4-6 hours prior to your appointment. Consuming any substance other than water may interfere with the results of your exam. Avoid exercise and unnecessary physical activity on the day of your appointment.
What to Expect
Depending on the type of nuclear medicine exam you are undergoing, the dose of radiotracer is then injected intravenously.
It will take approximately 60 minutes for the radiotracer to travel through your body and to be absorbed by the organ or tissue being studied. You will be asked to rest quietly, avoiding movement and talking.
You will then be moved into the PET/CT scanner and the imaging will begin. You will need to remain still during imaging. The CT exam will be done first, followed by the PET scan. The actual CT scanning takes less than two minutes. The PET scan takes 20-30 minutes.
Total scanning time is approximately 30 minutes.
You may leave after the scan is complete. If you normally drive, you should have no trouble driving yourself home. You may resume eating and drinking, unless otherwise instructed differently. Drinking plenty of fluids will help you excrete the radiotracer from your system.
After being injected it is advisable that you stay at least 10 feet away from children 18 years of age or younger and/or pregnant family members for a period of 24 hours.