North Pittsburgh Imaging Specialists



Positron Emission Tomography (PET) is a Nuclear Medicine technique that is used to detect abnormal biological activity in tissues throughout the body. Glucose (sugar) is combined with a radioactive tracer and injected into the bloodstream. Detectors are then used to locate areas of increased accumulation of the tracer compared to normal tissues. PET images supplement the information obtained from conventional studies such as CT, MRI, and Ultrasound.

PET can often detect small cancers before they are apparent on other types of exams because many cancers use glucose as their primary fuel. PET imaging can also be used to detect neurological disorders such as Alzheimer’s disease, Parkinson’s disease, and epilepsy. It also has a role in the diagnosis of coronary artery disease.

A new and powerful tool, PET Fusion, is now available that allows PET images to be digitally superimposed or fused to other imaging modalities (CT, MRI, and Ultrasound). This fusion process allows direct comparison of detailed anatomic information with molecular function. This additional information can help your doctor plan appropriate radiation therapy, biopsy, or surgery.

What Should I Expect?

We will evaluate you blood glucose level with a finger-stick. After this, a small intravenous catheter will be inserted into a vein in your arm. A radioactive tracer will be injected. The tracer, Fluorine 18-fluorodeoxyglucose (FDG), is a radioactive sugar that is used by your cells as fuel. The FDG is allowed to circulate throughout your body during a 45-60 minute uptake period. The small amounts of tracer that are used do not have any side effects. You will then be placed on a table in the PET scanner, where you will rest comfortably for the remainder of the study. The scanner makes very little noise. Depending on the particular type of exam, you may be required to place your arms above your head during the imaging process. Scan times vary depending upon your doctor’s request; the average scan time is 60 minutes. You should expect to be at the imaging center for a total of 3 to 4 hours.

How Should I Prepare?

You will need to fast for 6 hours before your scheduled exam. Tell your doctor if you are diabetic, as you will need to fast for 4 hours before the exam. Avoid nicotine, caffeine, sugar, and vigorous exercise for 24 hours before your exam and try to drink extra water. You should continue all other medications prescribed by your doctor unless informed otherwise.

You should wear comfortable clothing and avoid any clothing with metal. Any metal objects such as earrings, eyeglasses, or hairpins should also be removed. Women should always inform their technologist if there is any possibility of pregnancy.

How Do I Get the Results?

After your study is over, a radiologist will review and evaluate your exam. Both a preliminary and final report will be sent to your doctor, who can then discuss the results with you in detail. Often, for more immediate situations, our radiologists will speak directly with your referring physician to discuss the results of your procedure.

At any time before or after your procedure, our radiologists are happy to provide one-on-one consultations with you.