If you’ve never had an exam like a PET or CAT scan, you may be a little nervous. But there is no need to be afraid, as getting a PET scan is a non-invasive and painless procedure. Knowing what to expect during your exam will help you to be prepared and feel at ease.
What Is a PET Scan?
A PET or Positron Emission Tomography, Scan uses a small amount of a radioactive tracer given as a drink, an inhalant, or intravenously through a vein (IV). The tracer spreads through your body utilizing your circulatory system into the tissues and organs. The PET Scan detects the tracer and uses these readings to gather detailed information on things like blood flow, sugar metabolism, and oxygen use. That information can be further extrapolated to give your doctors information on the functionality of various tissues and organs, or perhaps to get a read on how well a cancer treatment is proceeding. It can also help to identify conditions like heart disease or brain disorders.
Before Your Exam
You may be asked to avoid eating or drinking for 4 to 6 hours before the scan. You will be able to drink water but not other beverages like juice or coffee. If you have diabetes, your provider will most likely tell you not to take your diabetes medicine before the test. These medicines will interfere with the results.
It is important that you do not exercise in a 24-hour window before the exam. The effects of exercise on the body could alter the readings.
You should disclose any history of allergic reactions. Reactions to the tracer are very rare, but still possible. Doctors of individuals who have a history of severe reactions may choose to pursue a different type of exam, or the technician may choose to keep a nurse nearby for safety.
Women should disclose any pregnancy or potential pregnancy, or if they’re breastfeeding. While the dose of radiation is low, it could still potentially have an impact on a developing fetus or a newborn. Your doctor may choose to utilize a different type of exam or postpone the test.
You should disclose any concerns regarding claustrophobia. Like an MRI or CT Scan, a PET Scan involves lying in an enclosed space for an extended duration. Your doctor or technician may sedate you to make the process easier to endure. If this is the case, you’ll want to plan ahead and ask a friend or family member to provide transportation to and from the appointment.
It is best to wear comfortable loose fitting clothing to your exam. You may be asked to change into a gown and remove jewelry or other accessories.
If there are any other requests or requirements, you will be informed at the time that you schedule your appointment.
What to Expect During the Exam
If you have not filled out your paperwork prior to your appointment, please plan to arrive at least 15 minutes prior to your appointment time. Be sure to bring your insurance information with you. A technician will review your paperwork and ask any clarifying questions.
You will first need to have the tracer injected into your bloodstream or given as a liquid dose or inhalant. If it is an injected tracer, you will likely feel a cold sensation moving up your arm away from the injection site. This is normal and should not be painful.
The tracer then takes up to one hour to fully disperse through your system. Because of this extended timeframe, you will want to ensure that you empty your bladder before beginning the process. As the tracer is moving through your system, please alert the staff on hand of any other side effects that you notice.
After the tracer is fully absorbed, you will be asked to lie on a narrow table that will then slide into a large tunnel-shaped scanner. You will need to lie still for an extended period to ensure good quality images, and you may be asked to hold your breath at times by the technician. You may be provided with, pillows or sandbags to help ensure that you are as comfortable as possible during the exam.
The PET Scan will then use the radioactive emissions to take three-dimensional images of your body. The images are displayed in an adjacent room for the technician to monitor and save for your physician to review. This process is entirely painless, and will take up to thirty minutes.
The machine will make clicking and buzzing sounds at times. Headphones with the music of your choice are provided to help you relax. The technician will leave the room while the exam takes place, but he or she will be watching through a window and you will be able to hear and talk to each other through an intercom to help you feel at ease.
What to Expect After the PET Scan
You may return to regular activities right away in most cases. Your images will be reviewed by a trained radiologist, who will consult with your doctor. Your doctor will notify you of the results within a few days.
If you were sedated to assist with claustrophobia, then you will need to allow time for the drugs to wear off. You will not be permitted to drive, so you will need to ask a friend or family member for a ride home after the exam.
If you have taken medication to reduce anxiety during your exam, you should avoid drinking alcohol or operating a vehicle or heavy machinery for several hours.
You should drink plenty of fluids to ensure that your system is flushed of the tracer.
Nursing mothers should wait 24 hours before resuming breastfeeding – ensuring to dispose of any milk pumped within that 24-hour window of the exam. It would be advisable to pump at the 24- or 25-hour mark and dispose of that before resuming regular breastfeeding.
Allergic reactions to tracer are rare, but possible. If you feel or notice any allergenic symptoms, such as itching, sneezing, rashes, hives, nasal congestion, itchy eyes, pain, nausea, vomiting, or dizziness, then you should notify the staff before leaving the diagnostic center. If you notice these symptoms after leaving, you should contact your doctor or proceed directly to the nearest emergency room.
If you have any questions or concerns before or after your exam, call us and we will be happy to help.