A PET/CT scan is a powerful imaging tool that incorporates two types of scans—positron emission tomography (PET) and computed tomography (CT)—to provide detailed pictures of your body. This scan is often used for cancer screening, as it helps doctors detect and monitor cancerous tissues and other abnormalities. If your doctor recommended a PET/CT scan, you’re probably wondering what to expect. This guide will walk you through the process, from how to prepare for the scan to what happens during and how long it takes.
What Happens During a PET/CT Scan?
A PET/CT scan involves two imaging techniques to create a comprehensive view of your body. The CT scan uses X-rays to produce detailed images of your body’s internal structures, while the PET scan tracks how your cells are functioning. This is done by detecting metabolic activity with a small amount of radioactive material, called a tracer.
Let’s look at the process in detail:
- Injection of the tracer: Before the scan begins, a technician will inject the radioactive tracer into a vein, usually in your arm. This tracer helps highlight areas of high metabolic activity, which can indicate the presence of cancer cells.
- Waiting period: After the injection, you will need to wait about 30-60 minutes for the tracer to travel through your body and accumulate in the areas being examined. During this time, you may be asked to relax in a quiet room and avoid movement.
- The scan: Once the waiting period is over, you will lie down on a table which moves into the PET/CT scanner. The machine is shaped like a large donut, and it takes images of your body as you pass through. The scan itself is painless, and you’ll be able to communicate with the technician throughout the process.
Imaging: The PET scan detects the tracer’s radiation to measure cellular activity, while the CT scan captures detailed structural images. Together, these images provide your doctor with valuable information about potential abnormalities in your body, such as cancerous growths.
How Long Does a PET/CT Scan Take?
The entire PET/CT scan process can take anywhere from 1.5 to 3 hours, depending on the specifics of your procedure and the area being examined. The actual scanning process typically lasts around 20 to 40 minutes, but you should allow extra time for the waiting period after the tracer injection.
How to Prepare for a PET/CT Scan
Proper preparation can help ensure accurate results from your PET/CT scan. It can also help you feel calm and relaxed, which is always important! Here are a few key things to keep in mind:
Fasting
You will likely be asked to fast for at least 4 to 6 hours before your scan. This is because certain foods, especially those high in sugar, can interfere with the results by affecting the tracer’s distribution.
Avoid strenuous activity
Intense physical activity before the scan can also affect the accuracy of the results, as it increases the metabolic activity in your muscles. It’s best to avoid exercise for 24 hours before the scan.
Wear comfortable clothing
You should wear loose, comfortable clothing with no metal (ex: zippers or underwire bras) on the day of your appointment. You may also be asked to change into a hospital gown for the procedure.
Inform your doctor
Let your radiologist know if you are pregnant, breastfeeding, or have any allergies, especially to contrast dyes or other materials that might be used during the scan.
Your PET/CT Scan: What to Expect
A PET/CT scan is a highly effective imaging tool for cancer screening and other diagnostic purposes. Understanding the process, from the injection of the tracer to the scanning itself, can help ease any concerns you may have, making the process as smooth as possible!
The scan is painless, and while it can take a few hours from start to finish, it provides your doctor with critical information to guide your diagnosis and treatment. Always follow your radiologist’s instructions for preparing for the scan.
Don’t hesitate to ask any questions about the procedure beforehand! Contact Southwest Diagnostic Center for Molecular Imaging at (214) 345-8300 today.
Sources:
https://radiology.ucsf.edu/patient-care/prepare/pet-ct
https://www.mayoclinic.org/tests-procedures/pet-scan/about/pac-20385078