PET-CT: Positron Emission Tomography


As the first center in the region to provide advanced molecular imaging services with a combined PET-CT scanner, today we continue to provide advanced PET-CT cancer imaging, bone imaging, brain metabolic imaging, and cardiac metabolic imaging. We are a fully Accredited PET-CT Facility, awarded by the ICANL division of the Intersocietal Accrediation Commission. We are an approved facility for the National Oncologic PET Registry, for both cancer imaging and bone imaging.

Combined PET-CT units increase patient comfort and convenience and have been proven to increase diagnostic accuracy.

Our PET-CT services are available for diagnosis, staging, and restaging of multiple types of cancers. Brain metabolic imaging can provide early diagnosis of Alzheimer's disease and other dementias, as well as pre-surgical evaluation for certain seizures. PET-CT imaging of the heart provides information on the distribution of metabolically functioning heart muscle in patients with myocardial infarction.

Stockton MRI is an approved and registered accredited participating PET facility with:

ICANL Accredited PET Lab Sealj

What is PET? Positron Emission Tomography, or PET, is a type of medical imaging test that provides your doctor with information about specific physiologic functions within your body. Patients who will undergo a PET scan will first be injected with a small amount of a specific radioactive tracer that emits charged subatomic particles called positrons. The interactions of these positrons in the body are detected by the scanner and allow an image to be recorded and processed in a computer. These images are then interpreted by an experienced physician. The type of radioactive tracer used depends on which physiologic function needs to be evaluated. The most common radiotracer in use today is FDG, which is helpful in evaluating metabolic activity throughout your body.

What is PET - CT? PET-CT is the combination of a Positron Emission Tomography (PET) scanner and a Computed Tomography (CT) scanner. A CT scan uses x-rays to create images that provide anatomic structural information about the organs within your body. Combining a CT scan with a PET scan improves overall image quality as well as the accuracy of the test. Stockton MRI & Molecular Imaging uses the GE Discovery ST PET-CT system.

What is FDG? FDG is basically a radioactive sugar. FDG refers to Fluorine-18 FluoroDeoxyGlucose, the most common radiotracer used in clinical PET-CT imaging today. An FDG molecule consists of two parts - the radioactive component Fluorine-18, and glucose, the sugar component that is recognized by your body. Fluorine-18 is a radionuclide that emits positrons, and therefore can be detected by a PET-CT scanner. Prior to your PET-CT scan, a small amount of FDG is injected intravenously into your body. Because it is made from a sugar molecule, FDG distributes throughout your body based on the metabolic activity of the various organs and tissues. Fluorine-18 decays quickly, and within a few hours is no longer significantly radioactive. For this same reason, it is very important that you arrive for your scan at your scheduled appointment time.

What information can a PET-CT scan provide to my doctor?

Cancer (Oncology PET-CT): Evaluation of cancers is the most common use of PET-CT scans today. Using FDG, a PET-CT scan provides information about the distribution of metabolic activity in various parts of your body. Certain cancer tissue (but not all) is known to be more metabolically in comparison to normal body tissue. Ongoing worldwide research has shown PET-CT to be useful in the evaluation of lung cancer, colon cancer, lymphoma, melanoma, breast cancer, esophageal cancer, cervical cancer, and certain thyroid and other neck cancers. For other types of cancer, research is continuing every day to help determine how PET-CT can provide useful information to your doctor. In most cases (but not all), a PET-CT scan can be used to provide helpful diagnostic information when cancer is not yet certain. More commonly, PET-CT scans are used when cancer is already diagnosed to determine the extent or spread (metastasis) of the cancer (also known as staging the cancer). After a patient has received treatment for the cancer, a PET-CT scan is useful in monitoring response to treatment, or evaluation for possible further progression or recurrence of the cancer over time (also known as re-staging the cancer).

Brain (Neurologic PET-CT): Your brain uses glucose, a sugar, for its energy. Using FDG, which is a radiolabelled glucose, a PET-CT scan can help to identify the regions of your brain that have more or less metabolic activity. In certain patients who have seziures, and surgery or other treatment is being considered, a brain PET-CT scan can be helpful in localizing the parts of the brain involved. Timing of the scan in relation to the seizure activity is important - metabolic activity in the brain will be altered during a seizure and between seizures. Another exciting use of brain PET-CT is in the evaluation of patients with signs or symptoms of dementia (such as changes in memory, language function, personality, or behavior), especially when your doctor is considering Alzheimer's disease as a possible diagnosis. Brain PET-CT scans of patients with certain types of dementias are known to show common patterns of metabolic activity within the cerebral cortex. Evaluation of patients for Alzheimer's diease with a brain PET-CT scan can help to identify which patients may benefit from treatment intended to slow progression of the disease, with the potential to provide benficial cost savings in the long run. 

Heart (Cardiac PET-CT): If you have heart disease and a history of prior myocardial infarction, the injury to the heart muscles can cause the overall function of your heart to decrease. In general, your primary physician, cardiologist, and/or cardiothoracic surgeon always weigh the potential risks versus the expected benefits for any possible therapy being considered for you. In selected cases, information about the metabolic activity of your heart muscles can help your physicians decide if certain therapy, including surgery, has the potential to improve the functionality of your heart. Using FDG, a PET-CT scan can help determine which areas of your heart muscle are viable. 

How do I prepare for my PET-CT scan? Do NOT eat or drink for at least 6 hours prior to your scheduled appointment. You may drink only water and your medications if they can be tolerated on an empty stomach. Other foods and drinks will affect the distribution of FDG in your body and will decrease the accuracy of your test.

We will contact you prior to the day of your test for further detailed instructions on how to prepare for your scan. These include additional steps you can take in order to make the test more optimal - including following a limited carbohydrate diet 24 hours prior to your test (click here), and avoiding strenuous exercise the day before your test.

What should I expect on the day of my PET - CT scan?

Please arrive at your scheduled appointment time. The radiotracer dose (FDG) you will receive will have been ordered in advance and prepared specifically for you hours before you arrive, and will be calibrated to your scheduled appointment time in order to maximize image quality.

Let the front desk know that you have arrived. We will ask you to provide us with more information about yourself, including your medical and surgical history.

You may be given a small medication in the form of a pill (Xanax, or alprazolam). This will help to optimize your scan by helping to temporarily reduce the amount of metabolic activity in various muscles of your body, including in your shoulders.

A Nuclear Medicine technologist will meet with you, who will check your blood glucose level. The technologist will then administer a small injection of the radiotracer (FDG) to you intravenously, usually into a vein in your arms.

You will then be allowed to relax in a quiet room for about one hour. During this hour the radiotracer is circulating throughout your body and is distributing into your tissues. Relaxation optimizes your scan by reducing the amount of metabolic activity in your muscles. Avoid talking, chewing gum, or any similar activity during this hour.

After one hour, the nuclear medicine technologist will take you to the scanner. You will be allowed to use the restroom in order empty your urinary bladder prior to the scan.

In the scanner room, you will lie down on a moveable bed which automatically positions you inside of the circular (doughnut-shaped) scanner. The entire procedure, which consists of a quick CT scan followed by a longer PET scan, will take about half an hour. You may be asked to position your arms above your head for the duration of the scan, depending on the images needed. Remain still during the scan in order to increase the quality of the images. The technologist will be monitoring you in an adjacent room at all times.

The technologist will inform you when your scan is completed. Once you are free to leave, you may resume your diet as before or as instructed by your doctor.

The images from your scan will be interpreted by an experienced physician. Your doctor will be informed of the results typically within 1 to 2 days.

PET-CT scan

Forms for PET-CT patients:

Patients may download, view, and print these PDF forms to complete prior to their scheduled PET-CT scan:


Our combined PET-CT unit brings together two advanced imaging technologies, providing patients with a single scan which improves patient comfort and convenience, as well as diagnostic accuracy.

Office Staff

Patty is one of our office staff who may greet you when you arrive for your scan.

Click here to meet the rest of our staff.

More PET-CT Information

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