Nuclear Medicine

Common Nuclear Medicine Exams:

• Nuclear Cardiac Stress Test
• Bone Scan
• Thyroid Uptake
• Renal Scan

What is Nuclear Medicine?

Nuclear medicine is a branch of radiology that uses radioactive materials to determine if certain organs such as the heart, kidneys, liver, thyroid, brain, and lungs are working properly. It is also used to examine the bones for cancer, infection or trauma. Nuclear medicine "scans" enable our physicians to determine how much heart tissue is still alive after a heart attack, or whether a kidney is operating as an effective filter, even when there are no detectable changes in organ appearance.

A typical Nuclear Medicine examination involves injection of a radioisotope (radiopharmaceutical) into the bloodstream. Other methods could involve digestion or inhalation of radiopharmaceuticals. Gamma cameras are used to detect signals given off by the radioisotope. Specially trained technologists use sophisticated computers to analyze this data to provide valuable information about the human body.

What are Some Common Nuclear Medicine Exams?

• Nuclear Cardiac Stress Test
• Bone Scan
• Thyroid Uptake
• Renal Scan

What is a Cardiac Nuclear Stress Test?

It is a diagnostic, non-invasive means of detecting the presence of coronary artery disease through a small injection of radiopharmaceutical material. Coronary artery disease is a condition in which there is narrowing or blockage of the blood vessels supplying the heart muscle.

How is a Nuclear Stress Test Performed?

A nuclear stress test is an assessment of blood flow to the heart. This assessment is done in two parts. The rest portion is performed first, followed by the stress portion.

Rest Component:
Upon arrival the nuclear medicine technologist places an IV (a small plastic catheter) into your arm, injecting a small amount of radioactive tracer called 99m Technetium (this is the nuclear part) through the IV line. Other than the minor discomfort you may feel from the IV, this test is safe and painless. There are not any allergic reactions or side effects correlated from the radioactive injection. The compound is completely different than the dye used in CT scans and IVP's. The technologist will then begin to scan your heart with the help of a gamma camera that detects the presence of the injected compound in your heart.

Stress Component:
This component involves treadmill exercise or a chemical compound that mimics exercise. Before the stress portion begins, the technologist will place electrodes (small pads) on your chest. These electrodes are then connected to an electrocardiograph (ECG) which monitors the rhythm of your heart. A physician will be at your side the entire time you are on the treadmill monitoring any changes that may take place. At your peak heart rate, a second injection of the radioactive compound is given, and a second scan of your heart is performed. Again, this injection is not harmful.

How Long Will I be on the Treadmill? And What if I Can't Walk on a Treadmill?

Each stress component is tailored completely for each individual patient, but the average is only 5-10 minutes. In the event that walking on the treadmill is not an option, our physician may option to administer an intravenous medication through your IV line that simulates treadmill exercise.

How Long Does a Nuclear Medicine Stress Test Take?

After each injection, approximately 30-60 minutes of time is allowed for the injection to distribute in the heart. Each scan, during the resting and stress components, takes 30 minutes to acquire. You should be prepared to spend 3-4 hours at the radiology facility.

What Type of Preparation is Required for a Nuclear Stress Test?

• You should not eat or drink 3-4 hours prior to the test. No caffeine is allowed the day of the test. Please remember that even decaffeinated beverages such as decaf coffee and tea carry a small amount of caffeine.

• Your physician may determine that certain medications you are taking may have to be stopped temporarily before the test to ensure the accuracy and the effectiveness of the test. Please discuss your current medications with your physician and inform the technologist of those medications.

• Since you will be exercising on a treadmill, it will help to wear comfortable clothing and footwear.

What Does the Nuclear Stress Test Show?

• If the scan is normal during both exercise and rest, then blood flow through the coronary arteries is most likely to be normal as well. Therefore, no significant coronary artery blockage would be suspected.

• If the scan is normal at rest but abnormal following exercise, (a reversible perfusion defect), then the heart is not receiving enough blood under stress. This may be due to blockage in one or multiple coronary arteries.

• Depending on the reason for your test, look to your physician to explain the results.

What is a Bone Scan?

A Nuclear Medicine Bone Scan is a diagnostic test used to detect infection, bone lesions, degenerative bone disorders or factures.

How do I Prepare for the Exam?

There is no preparation for this exam. If you have an outside imaging films or X-Rays, please bring them with you. It is helpful to have them to compare with your Bone Scan.

What Will Happen During the Exam?

This is a 2-part exam. You will receive an injection of a radioactive tracer into a vein. Pictures will be taken immediately following the injection. In some cases, you will be asked to return in 2-4 hours after the injection for more imaging. During this time, please drink 2-4 glasses of fluid. Empty your bladder as frequently as possible. When you return a scan will be taken from head to toe, using a gamma camera. You will lie comfortably on a scan table during the exam.

How Long Will the Procedure Take?

The first portion of the exam, when you receive your injection, will take approximately 15 minutes. The second part will take about 30 minutes to 1 hour.

What Will Happed After the Exam?

After the exam, the technologists will process your images using a computer. Radiographs may be requested after the scan. A Radiologist will evaluate the images within 24 hours and dictate a report. The report will then be forwarded to the ordering physician. You will get the results of the exam from your doctor.

If there is any possibility that you are PREGNANT or NURSING a baby, please speak with your referring physician before your scheduled appointment.

What is Thyroid Uptake and Scan?

A thyroid uptake and scan is a commonly performed nuclear medicine procedure that evaluates the structure of the gland and assesses its function. Radioiodine more accurately evaluates thyroid function, and it is the compound of our choice for routine applications. It is a 2-day procedure and it is performed using a small amount of radioiodine in a capsule form, which is given on the first day. In certain circumstances, you will be asked to return 6 hours later for thyroid uptake measurements using a probe. However, in most cases, thyroid uptake and scan is usually performed the next day.

Why is Thyroid Uptake and Scan Useful?

The goal of thyroid uptake and scan is to evaluate the function of the thyroid gland. Imaging procedures such as MRI, ultrasound and CT scans cannot provide this information.

How Long Does it Take to Perform Thyroid Uptake and Scan?

It usually takes approximately 60 minutes to perform thyroid uptake and scan.

What Type of Preparation is Required for Thyroid Uptake and Scan?

Thyroid medications interfere with the thyroid scan. If you are taking any thyroid medications, it is very important that you discuss it with your physician before scheduling the test. Depending on the information desired and the type of thyroid medication you are taking, you may have to discontinue the medications for a few days to a few weeks before the test.

What is a Renal Scan?

A renal scan is performed to evaluate the kidneys' blood flow and function looking for blockage, scars and infections. Renal scans can also determine if there is a narrowing in the artery of your kidneys.

How is a Renal Scan Performed?

During the renal scan you will be given a low dose radioactive compound injection that will enter the bloodstream, and is carried to your kidneys.

What Preparation do I Need for a Renal Scan?

No preparation is required.

How do I get my Results?

At NVRA, our radiologists will interpret your images promptly and the results will be forwarded to your physician either by phone, fax, and mail and or delivered electronically. Your referring physician will share the results with you.

Where can I Schedule my Nuclear Medicine Exam?

At NVRA, Nuclear Medicine services are available at:
(click on the facility for more info i.e. Hours, services, directions)

• NVRA @ 500 Chase Parkway in Waterbury
• Diagnostic Imaging of Southbury