Accurately detecting and diagnosing a variety of injuries and illnesses cannot always be left to a physical examination and/or a traditional x-ray alone. In some cases, a doctor may recommend that a patient undergo a PET scan, which utilizes state-of-the-art imaging to display organ and tissue function.
What is a PET Scan?
PET stands for positron emission tomography. A PET scan uses imaging to show how particular parts of the body are functioning. A PET scan utilizes a tracer to reveal the unique inner workings of the body. The tracer is a small radioactive drug that is swallowed, injected, or inhaled by the patient. The tracer material is drawn to – and gathers in – those areas of the body that have evidence of increased chemical activity which can signify the presence of disease. A PET scan can be enormously effective in revealing a variety of conditions that may have otherwise gone undiagnosed.
Why a PET Scan?
A PET scan is used to detect a variety of conditions including heart disease and some types of cancer. Because a PET scan specifically shows chemical activity in the body, it provides another level of information than that which is provided by a traditional x-ray, a CT scan, or MRI. For instance, a PET scan can help uncover cancer – or determine if cancer has spread – because cancer cells show up brightly during a scan. While not all cancers show up clearly on a PET scan, there are many that do including breast, lung, pancreatic, prostate, and brain cancer, among others. PET scans can also uncover heart disease by revealing a decrease in blood flow.
Undergoing a PET Scan
Preparation instructions will be given to you by your doctor prior to your PET scan. You will likely be asked to avoid exercise and stop eating prior to the testing. Patients are asked to remove their clothing and put on a hospital gown after which they will be given the tracer. This small radioactive drug may be injected, swallowed, or inhaled. Once the tracer has been completely absorbed – which can take up to an hour – you are ready to begin your PET scan.
Like a CT scan, a PET scan machine is shaped like a large ring. You lie on a small table and get comfortable. Once you are settled, the table itself will move into the scanner. The technicians will ask you to remain as still as possible so that the clearest pictures can be taken. The scanner moves around you so that pictures can be taken from all directions. While the procedure itself is painless, some patients may experience some anxiety connected to the loud clicking and banging noise of the machine or some claustrophobia if you become anxious in small spaces. Let your doctor know if you are concerned about this – or if you begin feeling anxious during the procedure. There is medication that may be available to help you relax.
The time spent in a PET scanner is approximately 30 minutes. Once complete, you are free to resume your regular activities although you will need to increase your fluid intake to flush the tracer material from your body. A radiologist will review the findings from your PET scan and then share them with your doctor. In some cases, your doctor may elect to combine a PET scan with a CT (computerized tomography) scan or MRI (magnetic resonance imaging) which can produce a clearer, more comprehensive diagnostic picture.