What is a PET Scan?
Positron Emission Tomography, or PET scanning, is one of the most advanced imaging tests available today. The test combines PET and CT (computerized tomography) images, to produce a traditional three-dimensional x-ray of the internal body structures allowing better evaluation and visualization of your body.
The PET scanner detects which cells in your body are using a large amount of sugar and then interprets this information to show areas of increased metabolic activity. Since cancers are overactive cells, the PET scanner is an excellent tool for determining if a suspicious area is cancerous or benign. It can also identify if cancer has spread to other locations, something not always possible with traditional x-rays.
What to Expect
When you arrive, an intravenous (IV) line will be started. You will receive an injection of a small amount of radioactive glucose (sugar) that has been prepared in advance for the specific time of your appointment. You will then rest quietly for one to two hours as your body starts to absorb the sugar. When you are ready for your scan you will lie on a table that will move slowly through a doughnut-shaped machine similar to a CT scanner. The scan itself is painless and will take between 15 and 30 minutes.
24 hours prior to your appointment:
- Discontinue or avoid strenuous exercise, sugar, tobacco products, and caffeine
- Drink 48 ounces of water 24 hours before your appointment
- On the day of your appointment, drink 24 to 48 ounces of water
- Continue to take any medications prescribed by your physician
For an appointment time between 7 a.m. and noon:
- Do not eat or drink anything for 12 hours before your appointment, except water.
For an appointment time between 1 and 4 p.m.:
- Do not eat or drink anything 4 hours before your appointment, except water. You may have a light breakfast with no sugar or coffee.
The total time you will spend at the hospital will be approximately 3 to 4 hours
After Your Scan
- You can leave immediately, and can resume normal activities
- You can resume your normal diet. Drink 24 to 48 ounces of water over the next 24-hour period
- The injection you receive loses its radioactivity very quickly, but as a precaution avoid being in close contact with infants or pregnant women for 24 hours following your PET scan
- It is recommended that breastfeeding be discontinued for 24 hours after this procedure and that someone else feeds the infant
- If you have diabetes, discuss this with your physician and call PET scheduling two days before your exam for further instructions.
- If you think you may be pregnant, or if you are breastfeeding, please call PET scheduling least 24 hours prior to your appointment.