Nuclear Medicine

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
• Blood flow and function of the heart 
• Respiratory and blood-flow problems in the lungs
• Organ function – of the kidney, bowel, gallbladder and others
• Tumor and infection involving bones and other organs

How should I prepare for this procedure?

Usually, no special preparation is needed. However, if the exam is done to evaluate the stomach, 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 imaging time can vary, the exam generally takes 20 to 45 minutes.

• A radiopharmaceutical, known as a tracer, is usually administered either intravenously or by mouth. Which 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 by means of your 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.

Nuclear Cardiac Imaging

What Is Nuclear Cardiology?

Nuclear medicine, or scan, uses a small amount of a radioactive substance to produce two or three dimensional images of the heart. These diagnostic images are used to evaluate Cardiac Anatomy and provide images of the structure and function of the heart.

What are some common uses of the procedure?

Physicians use nuclear cardiology studies to help diagnose cardiac disease. The symptoms include:

• Unexplained chest pain
• Chest pain brought on by exercise (called angina)

Cardiac nuclear medicine imaging is also performed:

• To visualize blood flow patterns to the heart walls, called a myocardial perfusion scan
• To evaluate the presence and extent of suspected or known coronary artery disease
• To determine the extent of injury to the heart following a heart attack, or myocardial infarction
• To evaluate the results of bypass surgery or other revascularization procedures designed to restore blood supply to the heart
• In conjunction with an electrocardiogram (ECG), to evaluate heart-wall movement and overall heart function with a technique called cardiac gating

What should I expect during this procedure?

You will be positioned on an examination table. A nurse or technologist will insert an intravenous (IV) line into a vein in your hand or arm.

The exam will begin with a stress test, which requires you to exercise either by walking on a treadmill or pedaling a stationary bicycle for a few minutes. While you exercise, the electrical activity of your heart will be monitored by electrocardiography (ECG) and your blood pressure will be frequently measured. When blood flow to the heart has reached its peak, you will be given the radiotracer through your IV. About a minute later, you will stop exercising and you will be positioned on a moveable examination table.

If you are unable to use a treadmill or bicycle, you will not exercise but you will be given a drug that will increase blood flow to the heart.

Approximately one half-hour later, the imaging will begin. Once the technologist has positioned the gamma camera, it will move slowly in an arc over your chest.

This same heart scan will be performed at another time, when you have not been exercising (called a resting scan). Images of your heart obtained after you exercise will be compared with images of your resting heart.

Actual scanning time for each heart scan varies from 16-30 minutes, depending on the type of scanner used. Total time in the nuclear medicine department will be approximately two to four hours.

When the examination is completed, you may be asked to wait until the technologist checks the images in case additional images are needed.