When you or a loved one faces a catastrophic disease, you want to make sure you leave no stone unturned when it comes to getting the right diagnosis. One extremely reliable test is the PET (positron emission tomography) scan. Every year, nearly two million PET scans are performed on patients to check for diseases such as cancer, heart problems, brain orders, and conditions with the central nervous system. PET scans are very similar to CT (computed tomography) scans in that they provide detailed images of the body. However, unlike a CT scan which shows the size and shape of organs and tissue, PET scans provide data at the cellular level, indicating with pinpoint accuracy the exact location of the issues with the body.
Doctors use PET scans, together with CT scans, X-rays and/or MRI (magnetic resonance imaging) to get a complete picture of what is wrong, where, and how. It’s a very intricate process, so it’s always good to know how these tests work so you can better understand your PET scan results.
How PET Scans Work
A form of nuclear medicine, PET scans are a radiology procedure often used or recommended by oncologists (cancer doctors), neurologists and neurosurgeons to detect abnormalities in the metabolism of an organ or tissue. PET scans use a special dye containing radioactive “tracers” that are injected into a vein and absorbed by certain organs and tissues. This enables doctors to examine a patient’s blood flow, oxygen intake, and how well their organs and tissues are functioning. The tracers collect in areas of higher chemical activity, making it easier to detect disease or concerning activity.
What PET Scans Can Reveal
While CT scans, MRIs and X-rays can detect changes in shape or mass, PET scans can detect actual physiological changes in the tissues and organs. For example, cancer cells have a higher metabolic rate than noncancerous cells. Because of their high level of chemical activity, the cells appear as bright spots on the PET scan. When such abnormalities are detected, doctor can determine whether the cancer has spread or if cancer treatment is working.
PET scans can evaluate brain trauma by detecting presence of bleeding or hematoma to the brain’s tissue. Neurologists recommend PET scans to diagnoses for dementia – particularly Alzheimer’s disease; as well as neurological conditions such as Huntington’s disease, epilepsy, and Parkinson’s disease.
Likewise, PET scans can reveal areas of decreased blood flow to the heart and which areas of the brain are utilizing glucose at the highest rate, thus revealing how well the brain is working and if there are any abnormalities.
I have been referred for a PET Scan. Now what?
Preparation for your PET scan begins 24-48 hours prior to your appointment; during that time you will be asked to drink a “barium” liquid contrast agent. It doesn’t taste great, but the more you are able drink the better the likelihood of more detailed images. You will have been provided with other special instructions beforehand to help you get ready. These instructions might discuss whether you are nursing, what clothes to wear, what medications you should or should not take, and eating instructions. The entire procedure generally takes three hours to perform. That includes registration, injection of the radioactive tracer, waiting period, and the time it takes to scan your body. Of course, actual scanning times may vary depending on the type of procedure ordered by your physician. However, 30 minutes is typically the average.
After you have been injected with the tracer, you will rest comfortably in a quiet room for up to one hour to allow the tracer time to distribute through your body. Just before the procedure begins, you will be asked to empty your bladder. Most of the radioisotope (the tracer) will collect in your bladder. After the test, you’ll be encouraged to drink plenty of fluids to flush it from your body.
Your PET/CT technologist will prepare your images for the radiologist, who will then forward the results to your physician within 24-48 hours after the procedure. Your doctor will then meet with you to discuss the results and answer any questions you may have.
Standardized, quantified PET scan results provide your doctor with insight into your condition so that appropriate treatment can be established. In the case of diagnosing or monitoring cancer, for instance, a PET scan helps to provide rapid and accurate information about tumor size, location, and rate of growth. By supplying functional data on cellular metabolism, a PET scan enables your physician to facilitate and optimize your individual health management.
At Independent Imaging, we provide state-of-the-art PET that offers superior image quality and performance. To learn more about our services, call Independent Imaging at (561) 795-5558 to request an appointment, or use our online request an appointment form.