Positron Emission Tomography (PET) is a non-invasive test that accurately images metabolic information in the body. PET can be performed to assist with the diagnosis and treatment of many cancer types and evaluate the function of the heart and brain.
When you arrive at our facility, you will be given an IV and your blood glucose level will be tested. You will then be taken to a recliner where the PET technologist will give you an injection through your IV. The injection is called FDG (fluorodeoxyglucose), which is basically a radioactive sugar. There are no adverse side effects or possible allergic reactions associated with this injection. FDG is a short-lived isotope that is shipped to the facility from out of state. It is for this reason that 24 hours of notice is required to schedule any patient for a PET scan. After the injection, you will rest in a recliner for approximately one hour. During this hour, it is very important that your muscles are completely relaxed. Therefore, you will only be allowed to listen to music. After that hour of relaxation, you will be asked to use the restroom to empty your bladder, and then you will be placed into the scanner. The scanner then utilizes the radiation coming from your body to take images of any cells that use sugar for energy. The scan usually images from the middle of your forehead to the middle of your upper legs in sections. For example, one 10 inch section of your head will be scanned, and then you will be moved out to scan the next 10 inches. Your head will be inside the scanner for about 20 minutes. You will be able to talk to the technologist at any time while you are in the scanner. It will take approximately one hour to complete your scan. For the PET scan described, the entire appointment will last approximately 3 hours.
Before you arrive
In order to get an accurate PET scan, we must make sure that your body will take up the sugar that we give you, and not the sugar that you eat. Therefore, you will be asked to eat protein and limited carbohydrates (and no high carbohydrate foods or sugars) the day before your scan. You will also be asked to not eat or drink anything but water 4 hours prior to your scan. Because your body metabolizes the FDG faster when you are hydrated, there are no restrictions on the amount of water that you drink, and you will be asked to drink at least 48 ounces (about 6 glasses) of water the day before, and about 12 ounces (about 2 glasses) of water the day of your scan. By staying hydrated, you will be improving the quality of your PET scan and reducing your radiation exposure from the FDG.
Examples of foods you can eat:
- Non-starchy vegetables: Lettuce, tomato, peppers, green beans, broccoli, cauliflower, mushrooms, peas, greens, spinach
- Meat (not breaded)
- Salad Dressing (less than 5 grams of carbs/serving)
Examples of foods you should avoid:
- Fruit, fruit juice, jelly, jams
- Bread, rolls, cake, tortillas
- Rice, pasta
- Soft drinks
- Yogurt, cereal, oatmeal
- Chips, crackers, popcorn
- Alcoholic drinks
- Desserts, candy
- Pizza dough, breading
- Starchy vegetables: Potatoes, corn, onion, beets, carrots
If you are diabetic
Please make sure our PET technologist knows that you are diabetic. For the same reason we give you sugar and carbohydrate restrictions the day before, we also need your blood sugar to be below 200. A blood sugar of 200 or above indicates that your cells are already saturated with sugar and will not take up the sugar we give you. If your blood sugar is normally above this value, please be sure to notify us. You must find a way to get your blood sugar below 200 before we can schedule you for a PET scan. If you take medications for your diabetes, you must not take those medications 4 hours prior to your scan.
Physicians – How to Order a PET Exam
PET has its own order form, mostly because it is very important that we get a detailed medical history on every patient. There are many medical conditions that can show FDG uptake, and an accurate read is dependent upon an accurate medical history. Therefore, if you cannot fill out the PET order form in its entirety, we ask that you send the most recent physician’s notes or history and physical with the order. We also ask that you send any recent pathology reports with every order. In order to give the patient the highest quality PET scan possible, the PET procedure is adapted to each patient. Some of the factors that can change the procedure are: tumor and cell type, patient’s renal function, patient’s weight, steroid use by the patient.
You may fax the paper order form to (208) 367-4953, or if you have web ordering, you may send the PET order through that as well. We will contact the patient to set up an appointment and go over prep instructions.
Q: What are some common uses of this procedure?
A: This procedure can be used to detect cancer, determine whether cancer has spread in the body, assess the effectiveness of a treatment plan, determine if a cancer has returned after treatment, determine the effects of a heart attack, and to map normal brain and heart functions.
Q: What are the risks?
A: The radiation risk is very low compared with the potential benefits because there is very low radiation exposure. The only real risk is an allergic reaction to radiopharmaceuticals, which is very rare and usually mild. Injection of the radiotracer may cause slight pain and redness, which should rapidly resolve.
Although IMI has several facilities, PET is only offered at the Meridian site. The address is: 2929 E. Magic View Drive, Meridian, ID 83642. This is located across the street from the St. Luke’s hospital on Eagle Road (near I-84), behind the Chevron and McDonald’s.