Detecting the health of internal tissues
Positron Emission Tomography (PET/CT) is a high-tech imaging technique that uniquely combines medical science with computer technology to see biochemical changes happening inside the body. Our PET scanner locates abnormal metabolic activity within body tissues long before anatomical changes related to a disease can be seen with other processes such as a CT or MRI. Our PET is used in conjunction with CT to provide more details, not only showing where a tumor or lesion is located, but whether it is benign (not cancer) or malignant (cancer), and whether previous treatment has been effective.
How PET works
A PET/CT scanner detects positrons (subatomic particles) given out by a radionuclide in the organ or tissue being examined. The radionuclides used in PET scans are chemical substances such as glucose (sugar), carbon, or oxygen that are used naturally by the particular organ or tissue being studied. Before you go into the scanner, a tiny amount of a radioactive substance is attached to the particular chemical required, making it visible by the PET machine. As the radionuclide breaks down, it emits positrons, which create gamma rays. The PET scanner detects the gamma rays and the attached computer analyzes the information to create an image map of the organ or tissue being studied. The amount of radionuclide collected in the tissue affects how brightly the tissue appears on the image and indicates the health of the organ or tissue studied.
How to prepare for your exam
Do not eat for at least four hours before your exam since the results of your test are affected by your blood sugar level. If you are diabetic, please notify our staff so we may give you special instructions.
Drink 24 to 32 ounces of water before your appointment time: being well-hydrated is important for your health at all times, but especially during a PET exam. Do not perform any heavy lifting or exercise the day before or the day of your PET scan. Wear comfortable clothing that may be easily removed for the scan.
If you require pain medication or relaxants to stay still during the scan, please tell our staff when your appointment is scheduled and when you arrive for your appointment, and bring the medication with you.
Please download and fill out this form and bring it in with you to your appointment. If you have had any imaging tests before this appointment, such as CT or MRI, be sure to let us know so we may review the previous images with your PET/CT scan.
What to expect at your appointment
Allow about two hours total time for your appointment, although we’ll try to take less of your time if we can. When you arrive for a PET/CT scan, you may be asked to remove any clothing, jewelry, or other objects that may interfere with the scan. (If you need one, you’ll be given a gown to wear.) You’ll then be asked to use the bathroom to empty your bladder. Your blood sugar will be tested and an IV will be started in your hand or arm.
You’ll receive a small amount of a safe, radioactive sugar via the IV. You’ll then be asked to wait very quietly in a seated area, as inactive as possible for 30 minutes to an hour. The injection will not affect others around you; the radionuclide emits less radiation than a standard x-ray.
After the radionuclide has been absorbed for the appropriate length of time, you’ll lie down on the scanner bed and the scan will begin. As you lie perfectly still, the scanner will move slowly over the body part being studied. The length of time between scans can vary depending on the body areas being studied, typically between 30 minutes to an hour. When the scan has been completed, the IV line will be removed.
After you leave, the technologist will complete the processing of your examination. When the study is complete and comparison exams are obtained, the radiologist will interpret the study and send a written report to your physician.
If you have any questions about your PET procedure that have not been answered here, please call our office at 812-333-7676.