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Call 866-258-4738 to schedule a PET CT scan.

A PET CT scan is a noninvasive, painless imaging procedure that helps your radiologist evaluate the structure and function of your organs and tissues.

PET stands for positron emission tomography, and CT stands for computed tomography. Together, both scans provide a picture of your organ and tissue function.

A PET CT scan is a critical tool that doctors use to determine how advanced cancer is, and the best way to treat it. The scan precisely measures the extent of disease to a greater degree than any other imaging tool we currently have.

PET scans are most often used to:

  • Detect cancer or cancer recurrence
  • Detect heart disease
  • Determine if and how much the cancer has spread
  • Establish the effectiveness of your current treatment plan
  • Evaluate brain abnormalities related to dementia or seizure disorders

How PET CT Scans Work

For a PET CT scan, you will be injected with a safe amount of radioactive material, called radiotracer.

A combination of PET and CT scanners then measure the amount of radiotracer your body absorbs and produce detailed images that represent the structure and function of your organs and tissues. The PET scan measures:

  • Blood flow
  • Oxygen use
  • Sugar (glucose) metabolism

The scanners provide images that show the exact location of any abnormal metabolic activity in the body and offer a more accurate diagnosis than when the PET and CT scans are performed separately.

Why We Use PET CT Scans 

PET CT scans and other nuclear medicine imaging studies look at the processes occurring in the body, rather than just looking at images of your anatomy. Areas of your body that show greater intensity of activity are called "hot spots." Hot spots indicate that there is a high level of chemical activity occurring in that portion of your body.

PET CT scans are especially helpful in assessing:

Benefits of PET CT Scans

You will only be asked to undergo a PET CT if your doctor believes it is essential to your care. In many cases, it is the only way for your doctor to get an accurate picture of your health condition. This test can detect early onset of disease better than other imaging tests.

Because a PET CT scan provides more detailed, reliable information about your health, your treatment may be shorter and have better outcomes.

Limitations and Risks of PET CT Scans

The PET CT scan may not produce images as visually clear as those produced by a traditional CT, MRI (magnetic resonance imaging) or other imaging procedure.

Diagnostic nuclear medicine procedures like PET CT scans have been used for more than 50 years. The risks are small, and the procedure results in low radiation exposure. There are no known long-term side effects from low-dose radiation exposure.

Though allergic reactions to the radiotracer can occur, they are rare and often mild.

How to Prepare for a PET CT Scan 

Your doctor or nurse will give you specific instructions prior to your PET CT scan, particularly if you are diabetic.

During the exam, you will either wear your own clothing or be asked to change into a medical gown. You will be asked to remove jewelry, hairpins, hearing aids, eyeglasses, and dentures.

What to Expect?

What to Expect Before a PET CT Scan

Do not eat or drink anything except water for six hours before your exam because food and beverages can interfere with the scan's results. Do not chew gum for six hours prior to the scan.

Always tell your doctor or technologist:

  • If you are pregnant or breastfeeding
  • If you have any allergies
  • What medications you are taking
  • If you have had any recent illness or have been diagnosed with any medical conditions, particularly diabetes
What to Expect During a PET CT Scan
Most PET CT scans are performed in an outpatient setting. The scan itself will take about 30 minutes, but you should plan to be at your doctor's office for at least two hours.

During the exam, you will be asked to lie on an exam table. A nurse or technologist will insert an IV into your hand or arm to inject the radiotracer. You will then wait about an hour for the radiotracer to travel through your body and be absorbed by the organ or tissue your doctor wants to study. During this time, you will be asked to rest quietly and remain still. You should not feel any discomfort or pain during the scan.

Once the tracer has cycled through your body, the imaging portion of the procedure will begin, starting with a CT scan, then a PET scan. After the scans are complete, you will be asked to wait for about 15 minutes, and then your technologist will give you a CD of your images.

Unless your doctor tells you differently, you can expect to resume normal activities immediately after your PET CT scan.
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