PET
What Is PET?

PET (positron emission tomography is a powerful diagnostic tool that, in many cases, renders answers that no other imaging tests can provide. This non-invasive procedure helps physicians in their diagnosis and treatment of certain diseases. Biochemical changes caused by certain diseases are detected by the PET scanner after a radioactive element, bound to a sugar like substance is injected into the blood. The distribution of this "tracer" is mapped by the scanner. Areas of abnormally high or low metabolism are seen on the image.

PET is fundamentally different than x-ray, CT, or MRI examinations in that PET produces an image of tissue metabolism. X-ray, CT and MRI exams are useful in producing images of structure, or anatomy. Metabolic abnormalities may be seen with PET prior to changes which are apparent with standard x-ray exams. For example, in Alzheimer's disease, where there is no major structural abnormality, PET is able to show a reduction in metabolism.