PET/CT & Nuclear Medicine

btn
PET/CT

PET/CT

What is Positron Emission Tomography?

Positron emission tomography, also called a PET scan, is a nuclear medicine exam that produces a three dimensional image of functional processes in the body. A PET scan uses a small amount of a radioactive drug to show differences between healthy and diseased issue. The diagnostic images produced by PET are used to evaluate a variety of diseases.

What are some common uses of PET?

  • most commonly, to assess cancer, or to assess the risk of cancer in a lung nodule
  • to evaluate the brain in some patients for memory disorders, brain tumors, or seizure disorders
  • to evaluate the heart for blood flow and ischemic heart disease

How should I prepare for this procedure?

PET is usually done on an outpatient basis. You should:

  • wear comfortable clothes and dress warmly, try not to arrive feeling chilled
  • not eat for six hours before your scan
  • drink plenty of water
  • consult with your doctor regarding the use of medications before the test

What should I expect during this exam?

  • You receive an intravenous (IV) injection of the radioactive substance.
  • The radioactive substance will typically then take approximately 60 minutes to travel through your body and be absorbed by the tissue under study. During this time, you will be asked to rest quietly and avoid significant movement or talking, which may alter the localization of the administered substance.
  • You will be positioned on the PET scanner table and be asked to lie still during your exam.
  • Scanning takes about 30 to 45 minutes.
  • Usually, there are no restrictions on daily routine after the test. You should drink plenty of fluids that help flush the radioactive substance from your body.

What will I experience during the procedure?

  • If given an intravenous injection, you will feel a slight prick. However, you will not feel the substance in your body.
  • You will be made as comfortable as possible on the exam table before you are positioned in the PET scanner for the test.
  • You will hear buzzing or clicking sounds during the exam.
  • Patients who are claustrophobic may feel some anxiety while positioned in the scanner.
  • Some patients find it uncomfortable to hold still in one position for more than a few minutes.

For more information on this topic, please visit www.Radiologyinfo.org.

Web Resources

What is PET?

Nuclear Medicine

PET/CT

What is Nuclear Medicine?

Nuclear medicine, or scan, uses a small amount of a radioactive substance to produce two or three-dimensional images of body anatomy and function. The diagnostic images produced by a nuclear scan are used to evaluate a variety of diseases. Sometimes a nuclear scan is combined with a CT scan.

What are some common uses of Nuclear Medicine?

Nuclear medicine images can assist the physician in viewing, monitoring, or diagnosing:

  • tumors, for example assessing for spread
  • blood flow and function of the heart and lungs
  • sites of possible infection
  • organ function – of the kidney, bowel, gallbladder, thyroid/parathyroid glands, and others

How should I prepare for this procedure?

Usually, no special preparation is needed. You may be asked to refrain from eating immediately before the test. If the exam is done to evaluate the kidneys, you may need to drink plenty of water before the test. 

What should I expect during this exam?

Although the studies vary, the imaging time generally takes 20 to 45 minutes.

  • A radiopharmaceutical, known as a tracer, is usually administered either intravenously or by mouth. What radiopharmaceutical is used and when the imaging will be done - immediately, a few hours later, or even several days after the injection, is dependent upon the type of exam you’re having.  
  • For most nuclear scans, you will lie down on a table and a nuclear imaging camera will be used to capture the image of the area being examined. The camera is either suspended over or below the exam table or in a large donut-shaped machine similar to a CT scanner. While the images are being obtained, you must remain as still as possible.
  • Most of the radioactivity is expelled out of your body in urine or stool. The rest simply disappears through over time.

What will I experience during the procedure?

Although usually done with a small needle, some patients experience some minor discomfort from the intravenous injection, or IV. Also, lying still on the examining table may be uncomfortable for some patients. You will hear low-level clicking or buzzing noises from the machine.

For more information on this topic, please visit www.Radiologyinfo.org.

Web Resources

About your nuclear imaging test

Medline Plus: Nuclear Scans

Download Patient Handouts

Cardiac Nuclear Medicine

English | Spanish

General Nuclear Medicine

English | Spanish

Radioactive Iodine (I-131) Therapy

English | Spanish

Thyroid Scan and Uptake

English | Spanish

[to top]

 


RagiologyInfo.org - Current and accurate patient information about diagnostic radiology procedures, interventional radiology and radiation therapy.