Excel Diagnostics

PET/CT: Positron Emission Tomography and Computerized Tomography

At Excel Diagnostics & Nuclear Oncology Center, we offer State of the art technology with the Siemens Biograph 16. Combination of PET and CT scan provides significant functional and anatomical information for detection, characterization and localization of the disease. This modality provides a significant contribution in the areas of oncology, neurology and cardiology for detection of disease conditions and monitoring response to therapy. The menu of agents for PET imaging will only increase in the future. PET/CT provides high contrast resolution imaging which is essential for correct diagnosis of a disease process. The study is typically completed in 2 hours after injection of the radiopharmaceuticals.  

PET/CT Applications

  • Determines the Extent of the Disease
  • Determines Location of the Disease for Biopsy, Surgery or Treatment Planning
  • Assesses the Response to and Effectiveness of Treatments
  • Detects Residual or Recurrent Disease
  • May Assist in Avoiding Invasive Diagnostic Procedures

Frequently Asked Questions

What is PET Scan?

Positron Emission Tomography (PET) and Computerized Tomography (CT) are both standard imaging tools that allow physicians to pinpoint the location of cancer within the body before making treatment recommendations. In the area of oncology, F-18 FDG PET scan  is highly sensitive for detection of increased sugar consumption also called the metabolic signal of actively growing cancer cells in the body and the CT scan provides a detailed picture of the internal anatomy that reveals the location, size and shape of abnormal cancerous growths. In one continuous full-body scan (usually about 30 minutes), the PET captures images of miniscule changes in the body’s metabolism caused by  the growth of abnormal cells, while CT images simultaneously allow physicians to pinpoint the exact location, size and shape  of the diseased tissue or tumor. In practical terms small lesions or tumors are detected with the PET and then precisely located with the CT. Alone, each imaging test has particular benefits and limitations but when the results of PET and CT scans are “fused” together, the combined image provides complete information on cancer location and metabolism. The bottom line is that you can have both scans – PET and CT – done at the same time thereby maximizing your imaging results.

What to Expect?

Some hints to prepare you for your scan:
Dress comfortably and warmly. Scanner rooms can sometimes be cool.
Avoid eating anything for at least four-six 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.

How is the procedure performed?

Be prepared to lie still for 15-75 minutes while the scan is performed.
A PET scan is completely painless and has no side effects. After fasting for 4-6 hours, you will receive an injection of a trace amount of radioactive glucose, which is distributed throughout the body.
About 30-70 minutes after the injection, you will empty your bladder, then lie down on a scanner bed. Images will be taken of your body as you lie still on the scanner bed.

How Long Will the Scan Take?

A scan takes approximately 15-90 minutes, depending on the type of scan you are having (i.e., whole body, brain, etc.) and the type of scanner being used. The results are then interpreted by a trained nuclear medicine physician or radiologist and sent to your referring physician.

How should patients with Diabetics prepare for PET scan?

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 scan. Test your blood sugar level before the PET scan. Make sure that the PET center staff knows that you are diabetic.

What do I need to do after my PET scan?

When the PET scan is done, make sure to drink plenty of water or other fluids throughout the day.

How do I receive my PET scan results?

Your PET scan results will be reported to your referring physician within 1-2 business days. Please contact your physician to discuss your PET scan results.

Is PET scan safe?

The risks associated with a PET scan are very minimal. The quantity of radiation is low and the FDG degrades quickly so that no detectable radioactivity is present after several hours. In addition to the radioactive decomposition, the remaining FDG is eliminated from the body through urine. Family members are not at risk for exposure since greater than 90% of the radioactivity has left the body or decomposed before the patient has left the center.

What is a Radiopharmaceutical?

A radiopharmaceutical is a radioactive drug. The most commonly used PET radiopharmaceutical is FDG, which is a radioactive form of glucose (sugar). Radiopharmaceuticals are produced by physicists and chemists.

What is FDG?

2-Deoxy-2-[18F]fluoro-D-Glucose, or FDG, is a type glucose (sugar) and is the most common radiopharmaceutical used in PET. To begin the PET procedure, a small amount of glucose is injected into your bloodstream. There is no danger to you from this injection. Glucose is a common substance that every cell in your body needs in order to function. Diabetic patients do not need to worry; it would take 1,000,000 doses of FDG to equal the glucose in 1 teaspoon of sugar.
FDG has a half-life of approximately 110 minutes, so it is quickly expelled from your body. FDG must pass multiple quality control measures before it is used for any patient injection.

What happens after my scan?

After your scan, you will get up from the scanner bed and check out with the receptionist. You will be notified when your results will be available to your physician.

FDG has a half-life of approximately 110 minutes, so it is quickly expelled from your body. FDG must pass multiple quality control measures before it is used for any patient injection.

Are there potential side effects to a PET scan?

No, there are no side effects to having a PET scan performed.

When will I get my results?

After the radioactive tracer is processed by the organ being studied and the scanner records the information, the images are interpreted by a trained radiologist. Your PET scan results will be sent to your physician generally within 24-48 hours of your PET scan.

How often should I have a PET scan?

If you are under a physician’s care, you should follow your physician’s recommendations for the frequency of having a PET scan.

Can I see my results?

Yes, your physician will have the PET scan results usually within 1-2 business days of your PET scan, and you may request a review of the PET scan results with your physician.

Are there alternatives to PET?

Yes and no. There are examinations that can be performed. However, there is no other metabolic (biological) scanning technique other than PET at this time. CT and MRI, for example, both examine the anatomical (physical) structure. Therefore, they can be useful in determining the size and location of a tumor; however, neither of them can determine whether a tumor is still active. No other imaging tool exists that scans for brain disorders.

Why is PET not well known? Why have I never heard of PET before?

While PET has been around for years, it has only been in the last few years that PET has moved from the research realm to the diagnostic/clinical sphere.

How many PET studies are performed per year?

Approximately 900,000 PET scans were performed in 2004. The number of PET scans are increasing dramatically, now that PET is no longer only for research. Currently the number of PET/CT scan is more than 2.5 million per year.

How does a PET scan differ from CT or MRI scans?

CT and MRI scans are anatomic imaging modalities, which means they look at the size and shape of organs and body structures. A PET scan is a metabolic imaging modality, which means it looks at function. The information collected from a PET scan is different from any other test that is available.

Is a PET scan painless?

The only pain involved is the needle prick when you receive the radiopharmaceutical injection which does not differ from any other type of injection..

What is the weight limitation of PET/CT Scan?

It is about 400 pound.