What is a PET scan?
PET is a nuclear imaging test that allows doctors to see how your body tissues absorb and use different chemicals in real time. The PET scan allows doctors to evaluate a variety of diseases anywhere in the body, including the heart and brain.
What conditions does a PET scan help diagnose?
PET scans are most often used to:
- Detect cancer and to examine the effects of cancer therapy by characterizing biochemical changes in the cancer
- Determine whether a growth is malignant (cancerous) or benign (non-cancerous)
- Evaluate the progression of disease
- Assess the effects of clinical therapies
PET can also measure blood flow, blood volume, oxygen usage, tissue pH (acidity), glucose (sugar) metabolism, and drug activity.
In addition, PET/CT is used to evaluate patients who have memory disorders such as Alzheimer's Disease, seizure disorders that are not responsive to medical therapy and for the assessment of cardiovascular disease.
Since PET measures the chemical activity of tissues some diseased such as diabetes or other metabolic disorders may give false results.
How should I prepare for a PET scan?
Your provider will give you detailed instructions on how to prepare for your scan. A general rule is:
- Do not eat anything for 4 to 6 hours before the exam
- Avoid strenuous exercise for a couple of days before the study
- Wear comfortable clothing
- Be prepared to stay for 2-3 hours
If you have any of the items listed below, please let us know so we can make arrangements for you before your appointment.
- Had a bad allergic reaction
- Have medical condition, such as diabetes
- Taking any medicines, vitamins or herbal supplements
- Pregnancy
- Breastfeeding
- Claustrophobia
What should I expect during a PET scan?
The PET/CT scanner is a large machine that looks similar to a CT scanners. From start to finish, the procedure takes about two hours to complete. You might receive contrast intravenously to enhance the images produced by the machine. You rest and remain silent in a reclining chair for 30 to 60 minutes while the radioactive substance takes affect. When you are ready, you lie on a narrow, padded table that slides into the scanner. During the scan, lie as still as you can. It takes about 30 minutes to complete a PET/CT scan. You won't feel anything, so please relax comfortably while the table moves throughout your exam.
After the test you can carry on with your day as usual unless your provider tells you otherwise. You'll need to drink plenty of fluids to help flush the tracer from your body.
What happens after a PET scan?
After your PET/CT scan, the images are reviewed by a trained radiologist. They interpret the images to diagnose any abnormalities or conditions. Your doctor will then discuss the results with you and recommend any necessary follow-up actions or treatments based on the findings.