General Nuclear Medicine Nuclear Medicine performs all diagnostic functional and perfusion imaging of non-cardiac structures. The most common studies include: whole body bone imaging; ventilation-perfusion pulmonary imaging with or without quantitation; renal scintigraphy (with/without Captopril); infection-inflammation whole body imaging with Gallium-67 citrate or Indium-111 labeled white cells; hepatobiliary imaging; thyroid scanning, uptake studies and therapy. Breast scintigraphy is also available. Other special studies can be arranged.
The Dual Source SOMATOM scanner speed, detail, and non-invasive nature make this one of the most exciting new technologies available today.
The SOMATOM Definition CT uses two x-ray sources simultaneously which makes it the fastest CT available. The ability of this technology to ‘freeze’ the motion of a constantly beating and moving heart is critical to capturing high quality images. The benefits include: twice the speed of other CT scanners, twice the resolution, high quality 3-D images, reliable imaging of all heart rates without medication, 50% less radiation compared with today’s single-source CT scanners, shortest breath-hold.
The Dual Source SOMATOM Definition CT provides anatomical detail not previously available, giving Deborah specialists more information to make diagnoses and treatment without invasive procedures.
The section performs single isotope cardiac studies individualized to the needs of the patient. The laboratory can perform Gated SPECT imaging to provide perfusion and functional assessment of myocardial viability. In addition to four SPECT cameras, the section has multi-crystal cameras for first pass angiography at rest or with exercise. The following studies can be done with exercise or pharmacological stress, with or without Gated SPECT imaging: thallium-201 perfusion imaging; thallium-201/technetium-99m sestamibi perfusion and functional imaging, and technetium-99m sestamibi perfusion imaging with or without functional assessment. Positron emission tomography for tumor identification or myocardial viability is available following telephone consultation with one of the physicians.
Nuclear Stress Testing A stress test, helps your doctor know how your heart works during physical activity. As your body works during any physical exertion, it requires more oxygen and energy. To meet this demand, the heart beats faster and harder.
The stress test shows if your heart gets enough blood from its own arteries to work harder, safely. Taking the stress test also helps your doctor know what type of exercise and how much is right for you. A nuclear stress test combines the treadmill portion with pictures (images) recorded on computerized gamma cameras. For the pictures the patient receives a small dose of a radioactive substance (Regadenoson), which the cameras can see. The radioactive substance can be thallium-201 or technetium-99m sestamibi (Mibi).
The basic stress test requires leads on the chest to provide the EKG signal. The EKG is the electrical signal the doctor monitors during the test. The doctor monitors your heart rate, heart rhythm, blood pressure, and looks for changes which suggest that the heart is not receiving enough blood for its needs. They will record an EKG at rest, at peak exercise, and afterwards. The doctor will ask about symptoms and how tired you feel.
At peak exercise the doctor or technologist will inject the isotope. The images are recorded and it may take 30 minutes. Then you must wait for about 4 hours. During this time your heart will rest from the exercise. After resting, you will have a second set of images. For the second set, you may require a second injection of the isotope. The doctor will compare the 2 sets of pictures to determine if the study is normal or abnormal.
Do not eat or drink after 12:00pm before the test.
Take your regular medications and your blood pressure meds.
If you are diabetic, do not take your insulin or oral medication. Bring the medicines with you.
Nuclear Stress Testing with Drugs
Some patients cannot exercise adequately. Patients with lung disease, arthritis, or disease in the leg vessels may not be able to walk. Patients with some medical conditions should not walk on the treadmill. For these patients the doctor can use a drug to effect the blood supply to the heart and simulate the effects of exercise. The drug may be persantine (dipyridamole), dobutamine, or adenosine. The drug is used with a radioactive substance (isotope) to assess the blood supply to the heart. The radioactive substance may be thallium-201 or technetium-99m sestamibi (Mibi).
For the test, you will receive the drug through a needle in your arm vein. At peak effect of the drug the doctor or technologist will inject the isotope. You will then have the images recorded. These pictures may take 30 minutes. Then you must wait for about 4 hours. During this time your heart will rest. After resting, you will have a second set of images. For the second set, you may require a "booster" injection of the isotope. The doctor will compare the 2 sets of pictures to determine if the study is normal or not.
Thallium-201 is the most commonly used isotope. It provides pictures of how good the blood supply to the heart muscle is. Mibi also provides information about blood supply. It is particularly useful in patients with larger chests. Mibi also provides pictures of heart function, which is helpful information in patients with suspected previous heart damage.
A third possibility is the use of the combination of the 2 isotopes to obtain function and blood supply pictures. This procedure does not require the 4 hour rest period, since the resting image is taken first.
Do not eat or drink after midnight before the test.
Take your regular medicine, including your blood pressure medicine. However, if you are taking theophylline, aminophylline or other medications for breathing, you must stop them 24 or preferably 48 hours, before the Persantine test. Speak with your physician.
If you are diabetic, do not take your insulin or oral agent. Bring the medication with you.
Common Questions About Nuclear Stress Testing with Drugs
Is it safe?
There is little risk and medical professionals are present to respond to any unusual happening.
What about the radiation?
The risk from radiation exposure is comparable to that of an x-ray.
Will I need other tests?
The results of the exercise test may suggest to your doctor that you need further studies. The results may also eliminate the need for further studies.
How long will it take?
The test takes about 5 hours total.
When will my doctor have the results?
Reports are mailed the next working day. Your physician should have the results within a few days.
I take persantine routinely. Will that interfer?
Persantine tablets will not interfer with the intravenous dose used. The intravenous dose is much higher than the tablets.