A positron emission tomography, or PET, scan is an imaging test that helps reveal how your tissues and organs are functioning. When you have a PET scan in Eau Claire, a radioactive drug, or tracer, is used to show this activity. This scan sometimes can detect disease before it shows up on other imaging tests. Depending on which organ or tissue is being studied, the tracer may be injected, swallowed or inhaled. The tracer collects in areas of your body that have higher levels of chemical activity, which often correspond to diseased areas. On a PET scan, these areas show up as bright spots.

A PET scan may help identify a variety of conditions, including many cancers, heart disease and brain disorders. Images from a PET scan provide information different from that uncovered by other types of scans, such as a CT scan or MRI. A PET scan or a combined CT-PET scan enables your provider to better diagnose illness and assess your condition.

A PET scan must be interpreted carefully because noncancerous conditions can look like cancer, and some cancers do not appear on PET scans. Many types of solid tumors do appear on PET scans, including:

• Brain
• Cervical
• Colorectal
• Esophageal
• Head and neck
• Lung
• Lymphoma
• Melanoma
• Pancreatic
• Prostate
• Thyroid

PET SCAN RISKS

Talk with your provider about the benefits and risks of a PET scan. If you are scheduled for a PET scan, a radioactive drug (tracer) will be put into your body. Because the amount of radiation you're exposed to is small, the risks of negative effects are is low. However, the tracer might:

• Cause a major allergic reaction, in rare instances
• Expose your unborn baby to radiation if you are pregnant
• Expose your child to radiation if you are breastfeeding

WHAT TO EXPECT PRIOR TO A PET SCAN

Your provider will give you detailed instructions on how to prepare for your scan. The PET scanner is a large machine that looks a little like a giant doughnut standing upright and is similar to a CT machine. In some medical institutions, a combined CT-PET scanner is used.

You'll need about two hours for the procedure. When you arrive for your scan, you may be asked to change into a hospital gown and empty your bladder. You will then be given the radioactive tracer. You'll need to wait 30 to 60 minutes for the tracer to be absorbed by your body.

WHAT TO EXPECT DURING A PET SCAN

The test is painless. You'll lie on a narrow, padded table that slides into the scanner. During the scan, you'll need to lie still so the images are clear. It takes about 30 minutes to complete the test. The machine makes buzzing and clicking sounds. If you're afraid of enclosed spaces, you may feel some anxiety. Be sure to tell the nurse or technologist about anxiety that causes you discomfort, so he or she may give you a drug to help you relax.

AFTER A PET SCAN

After the test, you can carry on with your day as usual, unless your provider advises otherwise. You'll need to drink plenty of fluids to help flush the tracer from your body.

PET SCAN RESULTS

A radiologist — a doctor specially trained to interpret scan images — will report the findings to your provider. The radiologist also may compare your PET scan images with images from other tests you've recently had, such as CT or MRI, or the images may be combined to provide more detail about your condition.