• About |
• What To Expect |
• Patient Preparation |
• Common Uses for the Test |
• Risks and Benefits

About

PET (Positron Emission Tomography) and CT (Computed Tomography) scans are both standard imaging tools that physicians use to pinpoint disease states in the body. A PET scan demonstrates the biological function of the body before anatomical changes take place, while the CT scan provides information about the body's anatomy such as size, shape and location. By combining these two scanning technologies, a PET/CT scan enables physicians to more accurately diagnose and identify cancer, heart disease and brain disorders.

What To Expect

Procedure
A PET scan is completely painless and has no side effects. After fasting for 4 hours you will receive an injection of a trace amount of radioactive glucose, which is distributed throughout the body.  You will rest in a quiet room for about 90 minutes.  Then you will empty your bladder, and lie down on a scanner bed. The equipment looks much like a CT scanner and is pictured on this page.  Images will be taken of your body as you lie still on the scanner bed.  You must be able to lie flat for at least ½ hour with your arms above your head.  If you feel you will not be able to do this, please call us at 888-1180 #3.

How Long Will the Scan Take?
A scan takes approximately 30-45 minutes, depending on the type of scan you are having (i.e., whole body, brain, etc.). The results are then interpreted by a GBI Radiologist and sent to your referring physician.

Diabetics
If you are diabetic, eat and take your insulin or oral medication as directed by your physician. Generally, your blood sugar level should be 100-200 mg/dL before your PET/CT scan. Test your blood sugar level before the PET/CT scan. Make sure that the PET/CT technologist knows that you are diabetic.

Patient Preparation

Some hints to prepare you for your scan:

• Dress comfortably and warmly. Scanner rooms can sometimes be cool.
• Avoid eating anything for 4 hours (before your scan (this includes sugar-free gum, mints, candy and beverages other than water).
• No strenuous exercise the day of your exam (example: working out, jogging, etc.).
• Please bring a copy of your most recent CT, X-Ray, or MRI films with you on the day of your PET scan if done somewhere other than Great Basin Imaging.
• Be prepared to be at the center for 2-3 hours.
• If you are having a diagnostic CT in addition to your PET/CT, you will receive additional instructions from our scheduling department.

Common Uses for the Test

Because it provides detailed, cross-sectional views of all types of tissue, CT is one of the best tools for studying the body. It is often the preferred method for diagnosing many different cancers, including lung, liver and pancreatic cancer, since the image allows a physician to confirm the presence of a tumor and measure its size, precise location and the extent of the tumor's involvement with other nearby tissue. CT examinations are often used to plan and properly administer radiation treatments for tumors, to guide biopsies and other minimally invasive procedures and to plan surgery and determine surgical respectability. CT can clearly show even very small bones as well as surrounding tissues such as muscle and blood vessels. This makes it invaluable in diagnosing and treating spinal problems and injuries to the hands, feet and other skeletal structures.

PET scans are used most often to detect cancer and to examine the effects of cancer therapy by characterizing biochemical changes in the cancer. These scans can be performed on the whole body. PET scans of the heart can be used to determine blood flow to the heart muscle and help evaluate signs of coronary artery disease. PET scans of the heart can also be used to determine if areas of the heart that show decreased function are alive rather than scarred as a result of a prior heart attack, called a myocardial infarction. Combined with a myocardial perfusion study, PET scans allow differentiation of nonfunctioning heart muscle from heart muscle that would benefit from a procedure, such as angioplasty or coronary artery bypass surgery, which would reestablish adequate blood flow and improve heart function. PET scans of the brain are used to evaluate patients who have memory disorders of an undetermined cause, suspected or proven brain tumors or seizure disorders that are not responsive to medical therapy and are therefore candidates for surgery.

Risks and Benefits

Benefits:

Unlike other imaging methods, CT scanning offers detailed views of many types of tissue, including the lungs, bones, soft tissues and blood vessels.

CT scanning is painless, noninvasive and accurate.

Diagnosis made with the assistance of CT can eliminate the need for invasive exploratory surgery and surgical biopsy.

CT scanning can identify normal and abnormal structures, making it a useful tool to guide radiotherapy, needle biopsies and other minimally invasive procedures.

Risks:

CT does involve exposure to radiation in the form of x-ray, but the benefit of an accurate diagnosis far outweighs the risk. The effective radiation dose from this procedure is about 10 mSv, which is about the same as the average person receives from background radiation in three years.

Women should always inform their doctor or x-ray technologist if there is any possibility that they are pregnant.

Nursing mothers should wait for 24 hours after contrast material (iodine) injection before resuming breast feeding.

The risk of serious allergic reaction to iodine-containing contrast material is rare, and radiology departments are well-equipped to deal with them.

Benefits:

Because PET allows study of body function, it can help physicians detect alterations in biochemical processes that suggest disease before changes in anatomy are apparent with other imaging tests, such as CT or MRI.

Because the radioactivity is very short-lived, your radiation exposure is low. The substance amount is so small that it does not affect the normal processes of the body.

Risks:

The radioactive substance may expose radiation to the fetus in patients who are pregnant or the infants of women who are breast-feeding. The risk to the fetus or infant should be considered in relation to the potential information gain from the result of the PET examination. If you are pregnant, you should inform the PET imaging staff before the examination is performed.