A positron emission tomography (PET) scan is an imaging test that helps reveal how your tissues and organs are functioning. These scans use radiation and a radioactive tracer drug that shows activity.
PET scans sometimes detect disease before it shows up on other imaging tests and is most commonly used in cancer treatment, neurology, and cardiology. These scans are used to diagnose, treat, and manage diseases and medical conditions.
When combined with a CT or MRI, PET scans can produce multidimensional, color images of the inner workings of the human body.
Before a PET scan, depending on which organ or tissue needs an examination, the tracer drug may be injected, swallowed or inhaled. The radioactive drugs in the tracer collect in areas of your body that have higher levels of chemical activity, including infected areas. On a PET scan, these areas show up as bright spots.
PET scan photos provide different information different from other types of scans. A PET scan or a combined CT-PET scan enables your doctor to better diagnose illness and assess your condition.
Here is how PET scans are used for cancer, cardiology, and neurology.
Cancer
Cancer cells higher metabolic rate than do normal cells. This causes them to show up as bright spots on PET scans. For cancer treatment, PET scans are useful for:
- Cancer detection
- Revealing whether your cancer has spread
- Evaluating treatment
- Finding a cancer recurrence
PET scans require careful interpretation. Many noncancerous conditions can look like cancer, and some cancers do not appear on PET scans. The following types of tumors do appear on PET scans:
- Brain
- Cervical
- Colorectal
- Esophageal
- Head and neck
- Lung
- Lymphoma
- Melanoma
- Pancreatic
- Prostate
- Thyroid
Heart disease
PET scans reveal areas of decreased blood flow in and to the heart. The results of your scan can help your doctor determine treatment such as angioplasty to remove clogged arteries or coronary artery bypass surgery.
When receiving a PET scan for a cardiac health issue, the tracers can help identify injured cardiac tissue to determine if the tissue is alive or dead, and if the tissue can be restored by increasing blood flow.
PET scans are used for managing many cardiac conditions and procedures:
- Coronary Artery Disease (CAD)
- Percutaneous Coronary Intervention (PCI)
- Heart damage and function
Brain
PET scans can be used to evaluate certain brain disorders:
- cancer
- Determining if cancer has spread to the brain
- Dementia
- Epilepsy
- Alzheimer’s
- Parkinson’s disease
- Differentiating between different conditions
