Nuclear Medicine/PET Imaging Exam

Viewing Both Function and Structure

Nuclear imaging is a specialized area of diagnostic radiology that enables physicians to evaluate bones, cardiac blood flow and organ function to detect the presence of disease, infection or physiologic dysfunction. These “physiologic images” of specific body processes are used to assess a wide variety of medical conditions that cannot be seen on conventional x-rays. Furthermore, nuclear medicine imaging often identifies abnormalities very early in the progress of a disease.


This imaging technique uses small amounts of radioactive materials that are detected by a special gamma camera to produce the images. These materials, which are administered to patients either orally or intravenously, expose patients to minimal radiation-no more than they would receive from a diagnostic x-ray. The benefits of nuclear imaging are substantial, providing a non-invasive and painless test that can detect problems at the cellular level.


Common Exams Performed

  • Myocardial Perfusion Scan – Examines coronary blood flow to the heart muscle
  • Hepatobiliary (HIDA) Scan – Examines gallbladder function
  • Gastric Emptying Scan – Examines the rate of stomach emptying
  • Thyroid Uptake & Scan – Quantifies hyperthyroidism, hypothyroidism and structure abnormalities
  • Bone Scan – Detects primary cancer metastases, small fractures and infections
  • Lung Scan – Determines high or low probability of pulmonary embolism


About the Procedure

These scans involve injecting, swallowing or inhaling very small amounts of radioactive drugs called radiopharmaceuticals. The radiopharmaceutical selected for your scan is dependent on the organ being imaged. As the radiopharmaceutical travels to the area being examined, a special camera detects the photons released by this radioactive material and maps their distribution.

The nuclear medicine cameras are connected to computers that process the information to produce pictures for the Radiologist to interpret.

Within one to two days, all traces of the radiopharmaceutical disappear from the body. These procedures are safe and painless, and the amount of radiation from a nuclear medicine exam is comparable to that of a diagnostic x-ray.

Finally, there are no common side effects in nuclear medicine.



Most nuclear medicine exams require simple preparation. The most common preparations are nothing by mouth 4 to 6 hours before your exam. Occasionally, you will be asked to discontinue certain medications for a specific length of time prior to your exam. Your physician will inform you of these requirements in advance of your exam. If you have any questions, the nuclear medicine staff at CRL Imaging will be happy to help you.

Since imaging rooms can be chilly, please dress in warm, comfortable clothing. We will ask you to remove metal objects like belt buckles, coins and keys.

Please arrive at the imaging center 10-15 minutes prior to your scheduled exam time. A technologist will discuss your procedure with you, answer your questions and take other needed information.

Please bring your list of medications, x-rays, CT scans or other pertinent test results with you.

If you need to cancel your nuclear medicine exam, please notify your imaging center at least 24 hours in advance since the radioactive material is ordered specifically for you on the day of your exam and cannot be stored for future use.


During the Procedure

In the nuclear medicine room, you will sit in a chair or lie on a table where a technologist will administer the radiopharmaceutical – most often by injection into an arm vein. Depending upon your procedure, you may be under the camera during the injection. For most exams, you must wait for the radioactive material to be distributed to the organ being imaged. Waiting times vary from immediate to several hours to a day. If waiting time permits, you may walk around or even leave the imaging center.

Following the required waiting time, you will lie on an imaging table with the camera above and/or below you. The camera may move very slowly around you or remain stationary depending upon your particular exam.

You will be able to speak to the technologist at any time.

You may be asked to remain perfectly still for several minutes at a time while the image is recorded.


After the Procedure

After your exam, you will be asked to wait 10-15 minutes while the scans are finalized and then shown to the Radiologist. As soon as the scans have been reviewed for clarity, you may go home. If additional scans are needed, they will be taken at this time. Unless advised otherwise by your physician, you may resume your normal diet and activities immediately.



A board-certified Radiologist will interpret the scan and relate its information to the referring physician, who will in turn inform you of the results. All written reports will be available to the referring physician within 24 hours. Any time immediate attention is needed, the referring physician will be contacted the day of the exam.