What is a PET-CT?Positron emission tomography and computed tomography (PET-CT) have revolutionized cancer care by providing detailed scans for diagnosis, surgical planning, treatment planning as well as treatment monitoring. With PET-CT, doctors can detect tumors nearly three times smaller than masses visible on traditional scans. It also enables them to better determine whether a mass is malignant (cancerous) or benign (not cancerous). What doctors see in a PET-CT image that distinguishes cancer from healthy tissue is the accumulation of a radioactive substance called a radiotracer in the cancerous tissue. This radiotracer is glucose-based and is injected prior to the scan.
Before Your Exam
To assure that your body absorbs the radioactive sugar properly, please follow these instructions.
- Do not eat or drink anything except water for four hours before your exam. You may want to bring a snack with you to eat after the exam, once the nurse or technologist gives you permission to do so.
- No alcohol, chewing gum or caffeine 12 hours before your exam.
- No nicotine two hours before your exam.
- No vigorous exercise 24 hours prior to scan.
- Unless instructed otherwise, take all prescribed medication(s) on the day of your appointment. If you have been advised not to take medication(s) on an empty stomach, please wait until after the exam is complete to take your medication(s). If you are diabetic or insulin dependent, you may take your medication or insulin four hours prior to the scan with a low-carbohydrate meal.
- You may be asked to change into a hospital gown for the scan. Otherwise, wear loose, comfortable clothing without zippers, buckles, buttons, wires or any metal. It is best not to wear jewelry, since you will most likely be asked to remove it.
- If you are or think you might be pregnant or are currently breastfeeding, let your doctor and our imaging-services staff know.
- If you have any iodine allergies, please let our imaging-services staff know.
How is a PET-CT performed?
Prior to your exam, a technologist will inject a small amount of radioactive glucose into your arm.
You will then be directed to sit alone quietly and very still for 60 minutes, which gives the tracer ample time to circulate through your body.
For the scan, you will be asked to lie very still on a padded table, which moves slowly through the scanner’s chamber as it captures the information needed to generate diagnostic images.
A technologist will be stationed in a nearby room. They are present throughout the exam and able to communicate with you through an intercom.
While the actual scan takes approximately 20 minutes, the entire process can take up to three hours, so plan your day accordingly.
After Your Exam
You may leave as soon as your exam is completed. Unless you have received special instructions, you may eat, drive, resume normal activity, exercise and take all prescribed medication(s). Drink plenty of water and fluids throughout the day after the exam and empty your bladder frequently to flush the glucose tracer from your system. If you took a sedative for anxiety before the scan, please arrange to have someone drive you home. Due to the type of radiation used for this study, you should not be in close contact — maintain a distance of five feet — with children or pregnant women for the remainder of the day.
Results from the procedure will be sent to your ordering physician within two business days. You may also access your medical records online by creating an account at FloridaHospital.com. If you have any questions regarding your exam, please don’t hesitate to ask your technologist.
Many people who suffer from claustrophobia are able to tolerate our exam due to the openness of our scanner. However, if you are concerned that this could be an issue, please contact your ordering physician to obtain medication to bring to your appointment.