What?
Positron Emission Tomography, or PET, is a medical imaging technology that enables physicians to view how organ systems of the body are functioning at a cellular level. PET, a non-invasive test, is unsurpassed as a definitive diagnostic tool because it can help the physician detect disease (such as cancer, or Alzheimer's), determine appropriate treatment for that disease, and efficiently track the body's responses to the treatment.

Why?
PET is a medical diagnostic imaging procedure that provides physicians with information about the body’s chemistry, cell function, and location of disease – information not seen through CT, MRI, X-ray, blood test, or physical examination. While CT or MRI look at anatomy or body structure, PET studies body function or the biology of diseases. Because changes in the metabolism occur before anatomical changes are apparent, PET often reveals illness much earlier than conventional diagnostic procedures. This advantage eliminates the need for ineffective or unnecessary surgeries, treatments or other diagnostic tests, significantly reducing medical costs and patient discomfort and potential complications. In fact, some studies have shown that up to 60 percent of invasive tests or surgeries can be eliminated with PET.

How?
A PET scan is completely painless, with no side effects. After fasting for four hours, you will receive an intravenous injection of radioactive glucose, which is distributed throughout the body. About 45 minutes to one hour after the injection, you will lie on the scanner table for the duration of the test - a 15-75 minute procedure, depending on the type of test.

After the radioactive tracer is processed by the organ being studied and the scanner records the position of the tracer, the image results are interpreted by a trained nuclear radiologist. Results are reported to your referring physician within 24 hours.

Medicare covers PET scanning for many uses, including lung, colorectal, esophageal, melanoma, lymphoma, and head and neck cancers. Most private insurers cover PET scans as well. Check with your physician about your insurance coverage.

A More Complete Picture
Common Uses of PET

Oncology
• Assess tumor aggressiveness
• Monitor success of therapy
• Early detection of recurrent tumors
• Whole-body survey for cancer that may have spread
• Determine benign from malignancy in suspicious areas 

  Neurology

• Diagnose Alzheimer's and other dementia
• Epilepsy - precise location for surgery
• Parkinson's - diagnosis of movement disorders