Positron Emission Tomography (PET)
Positron emission tomography (PET) is a nuclear medicine procedure that produces pictures of the body’s biological function.
How do I prepare for a PET scan?
Your physician will advise you, but typically, patients are asked not to eat or drink anything besides water for four to six hours prior. Take any prescribed medications on exam day unless the physician instructs otherwise. Diabetic patients should ask about specific diet guidelines to control glucose levels during the day of the test. You may wear comfortable clothes during the exam.
What can I expect during the PET scan?
Before the scan, you will be injected with a radioactive tracer, which is a compound such as glucose, labeled with a short-lived radioisotope. You then will be asked to rest for approximately 30 to 45 minutes while the radioactive compound distributes throughout your body and is processed by the organs being evaluated. Different colors or degrees of brightness on a PET image represent different levels of tissue or organ function. The radiation exposure associated with PET is safe and much lower than that associated with conventional CT scanning. You will lie on the scanner table, which will then slowly pass through the PET scanner. The scanner detects and records the emitted tracer signals. The signals are then reassembled into actual images through a computer.
How long will my PET scan take?
Every PET exam is different, but most patients are at the clinic for at least two hours. This includes the time needed for the injected tracer to distribute throughout your body, as well as the time actually spent moving through the PET scanner. The exact length is determined by the type of study being performed.
What will happen following my PET scan?
You should feel fine following your PET scan. There are no known side effects from the injected tracer.
How do I find out the results of my PET scan?
Your PET scan will be reviewed by a radiologist. Your health care provider will receive a copy of the results to review with you. It usually takes one to three days to interpret, report and deliver the results. In order to facilitate interpretations, you may be asked to bring any previous radiologic images with you, such as recent CT or MRI images.