A positron emission tomography (PET) scan uses a special camera and a substance called a tracer to look at organs in your body. These scans can help identify a range of conditions including cancer, heart disease, and brain disorders. PET scan images can detect cellular changes in organs and tissues earlier than other imaging tests such as CT scans and MRIs.
You may be prescribed a PET scan if your doctor wants to look more closely at:
Before your PET scan, you will receive an IV injection of a radioactive drug called a tracer, which is absorbed by certain organs and tissues. On PET scan images, the tracer indicates normal and abnormal activity.
FDG-PET/CT Scan
This type of scan uses a tracer called fluorodeoxyglucose (FDG) to look at the metabolic activity of cells. It can detect many types of cancer at an earlier stage than CT scans or MRIs and can show if a treatment is working even before there is a change in tumor size.
PSMA PET/CT Scan
Prostate specific membrane antigen (PSMA) PET/CT imaging looks for prostate cancer cells in the prostate gland and in other parts of the body. The PSMA PET/CT scan may also help determine if you are a candidate for treatment with a cancer-targeting drug called a radiopharmaceutical.
SSTR PET/CT Scan
A somatostatin receptor (SSTR) PET/CT scan can identify small neuroendocrine lesions and tumors that can develop anywhere endocrine cells are present but cannot be seen on CT scans or MRIs. They can also help determine if lesions are likely to progress to neuroendocrine tumors and if you may be a candidate for cancer treatment with radiopharmaceuticals.
FES PET/CT Scan
This scan uses a tracer called fluoroestradiol F18 (FES) to look for breast cancer cells that have spread to lymph nodes or other parts of the body. It can also be used to ensure your treatment is working or to determine if you are a candidate for hormone therapy.
Brain PET Scan
A brain PET scan may be ordered by your doctor to evaluate and diagnose a variety of conditions such as brain tumors, seizures, cognitive impairment, and brain injury. When evaluating brain tumors, the PET scan is conducted with a separate brain MRI. For an epilepsy diagnosis, EEG monitoring is often performed at the same time as the PET scan.
Cardiac PET Scan
Cardiac PET scans can be used in several ways to evaluate cardiovascular disease and heart function. Blood flow to the heart can be viewed at rest and during exercise to diagnose ischemia (reduced blood flow) and help choose the best treatment strategy. These scans can also help determine if damaged heart muscle is likely to recover after a heart attack and to diagnose and treat people with cardiac sarcoidosis, a rare but life-threatening heart condition.
Getting Ready for Your PET Scan
Wear warm, comfortable clothes without zippers, buttons, or metal. Depending on the part of the body being scanned and the tracer used, you may have dietary or other restrictions. Duke MyChart or your provider will give you detailed instructions on how to prepare for your scan. Following these instructions is important for getting the best images possible and helping your doctor make the most accurate diagnosis.
The PET Scan Machine
A PET scanner is shaped like a ring or a donut. You will lie on a table that glides slowly into the machine as the scan is conducted. Your doctor may order a PET scan and a CT scan at the same time. A combined PET-CT produces 3D images that can help your doctor make a more precise diagnosis.
PET Scan Safety and Comfort
Tell your doctor if being in an enclosed space makes you anxious. If needed, your doctor may be able to prescribe anxiety medicine to take for the procedure. The tracer used for the scan does not have side effects and will not make you feel different. Your body will eliminate it quickly after the test. Drinking extra fluids for 24 hours after the scan can help flush the tracer out of your body. The risks of getting a PET scan are minimal compared to the benefits of diagnosing serious medical conditions.
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The entire PET scan process takes about two hours. This allows time for IV insertion, tracer injection through your IV, tracer absorption, and the PET scan.
Tracer Injection
You will receive an injection of a tracer that contains a safe amount of a radioactive drug. This may be through an IV catheter inserted in your arm or hand. You will relax for about an hour while your body absorbs the tracer. Depending on the type of scan and the reason for your test, you may be given an oral solution (contrast) to drink.
During the Scan
You will be asked to remove metal items including jewelry and belt buckles. You may need to change into a gown. You will lie on a table, which will slowly move through the PET scan machine. You may hear clicking and whirring noises as images are generated. It is important to lie still because movement can cause blurry images. Your technologist may ask you to hold your breath for short periods or change position during the scan. Depending on your medical condition, you may have a full-body scan or a partial-body scan. Once the PET scan begins, it will take about 15 minutes to one hour to complete.
Once your PET scan is complete, your images will be interpreted by a radiologist or nuclear medicine doctor who specializes in PET imaging. Your report and images will be available through Duke MyChart for you to discuss with your doctor.
Since you will be able to access your results as soon as they are available, you may see them in MyChart before your doctor has had a chance to look at them and explain them to you. If you prefer not to see your results before your doctor, let them know. They can request a delay in sending your information to MyChart until you have the chance to talk with them.
A team of nuclear medicine doctors, radiologists, medical physicists, and specially trained technologists and nurses work together to ensure your PET scan is safe and high-quality. We are accredited by the American College of Radiology (ACR), meaning we provide the highest level of safety and image quality. Our scanners also undergo rigorous internal quality control, which exceeds even the high ACR standards. These accreditations and quality control programs demonstrate our commitment to providing you with the best experience possible.