What is a PET Scanner?

Positron Emission Tomography (PET) scans measure emissions from positron-emitting molecules. In the 1970s, PET scanning was introduced to the medical community. During the 1980s, the technology that underlies PET advanced greatly. Commercial PET scanners have resolution that is more precise and images that are more accurate than CT scanners. Many of the steps required for producing a PET scan are performed by a trained technician or an experienced physician, thereby reducing the cost and complexity of the procedure. The main difference between the CT and PET scans is the PET scan shows molecular function and activity instead of structure, and therefore can often differentiate between normal and abnormal tissue. A PET scan produces three dimensional images and usually compliments rather than replaces the information obtained from a CT scan. By measuring blood flow and metabolic rate within the heart, physicians using PET scans can discover areas of decreased blood flow, such as those areas with blockages, and differentiate living muscle from damaged muscle that has inadequate blood flow. This information is particularly important for patients who have had previous myocardial infarction or who are being considered for a procedure such as a coronary artery bypass surgery or angioplasty.