Nuclear Medicine

WHAT IS NUCLEAR MEDICINE?

Nuclear Medicine is imaging following the administration of a small amount of a radioisotope. It is like x-ray except that instead of an x-ray beam passing through your body from outside, this very small dose of radiation (radioisotope) is delivered internally via injection or capsule and is absorbed by the body. Various organs in the body can be imaged with this modality. These scans can provide information that is not obtainable through other imaging exams about physiologic processes within the body and how well organs are functioning as opposed to just the body’s structure. Some radioisotopes can be utilized as a treatment for certain medical diseases.

CAN I HAVE A NUCLEAR MEDICINE SCAN? WHAT ARE THE RISKS?

Nuclear Medicine scans are safe because only small amounts of radioactive material that have a short half life are used. The radiation risk is very low for these scans, which carry about the same risk as an x-ray. There are no known long-term adverse effects, and allergic reactions are extremely rare.

Radioisotopes should not be given to women who are pregnant or breast-feeding. Please tell your physician if you are pregnant or breast-feeding. The risks and benefits of having a Nuclear Medicine scan should then be discussed with your doctor to determine the best course of action. Also, please tell the technologist if you are allergic to iodine, shellfish or any medications.

HOW DOES NUCLEAR MEDICINE WORK?

Depending on the type of Nuclear Medicine exam that you are having, you will receive radioactive material either by IV, direct injection into the vein in your arm, or by swallowing a capsule. The radioisotope is absorbed by the target organ and gives off energy in the form of gamma rays. These gamma rays are detected by the nuclear camera or probe, which work together with the help of a computer to measure the amount of radioisotope absorbed by your body and to produce images that reveal detailed information about the structure and function of organs and tissues.

These images may be taken with various types of equipment. Stationary gamma cameras are large cameras that are positioned close to the patient while the patient lies on the imaging table. SPECT (single photon emission computed tomography) or rotating gamma camera heads, move around the patient as the patient lies still on the imaging table. As part of thyroid imaging, a probe is used to measure the amount of radioactivity in the thyroid gland. This probe is placed in front of the patient’s neck and readings are taken.

PREPARATION FOR YOUR SCAN

Bone scans and Triple phase bone scans:
No fasting is required. An injection is given at the appointment time and you are required to return approximately three hours later for imaging. During those three hours you must drink extra fluids.

Biliary scan (Hida scan) or Gastric emptying study:
Nothing to eat or drink for 6 hours prior or overnight. These studies take approximately 1½ hours to complete.

Thyroid scan:
This scan is a two-day test and no prep is required. On the first day, you will fill out a history sheet and take a radioactive iodine capsule. Bloodwork will be drawn if necessary. This will take approximately 15 minutes. If you are hyperthyroid, you may need to return in the afternoon. On the second day, you will return in the morning for imaging.

Meckels diverticulum:
Fasting is required on the day of the test. In addition, you must take Cimitadine (Tagamet) in 200 mg tablets. One tablet is taken the day before the test and one tablet is taken the morning of the test.

Renal scan with Lasix:
Fasting is required for this test except for two glasses of water that should be consumed before arrival to the hospital. This test will take about 45 minutes. No Lasix, (furosemide) or any other diuretic should be taken the day of the test.

Renal scan with Captopril:
Fasting is required. This test will take approximately 1 ½ to 2 hours.

Cardiac perfusion stress test:
Fasting is required for this test and you should not consume any caffeinated drinks or food the morning of the scan. Wear loose-fitting clothing and comfortable walking shoes. Female patients are asked to wear a bra and no pantyhose for this procedure. It is important that you bring in a list of all medications including the milligram amounts. Medications may be taken the day of the test unless your doctor has instructed otherwise. This test will take approximately 3 ½ -4 hours.

Lymphoscintagraphy:
No fasting is required for this procedure unless surgery or a biopsy is to be performed immediately after the scan. The procedure will take approximately 1 to 1½ hours to perform.

WHEN TO ARRIVE/WHAT TO EXPECT WHEN YOU DO

You should arrive in the Nuclear Medicine Department on the ground floor at your appointment time. You are already registered for the scan, so there is no need to stop at Outpatient Registration. The Nuclear Medicine technologist will interview you to obtain a medical history, as well as to provide an explanation about the test and answer any questions you may have.

If you are receiving an injection of radioisotope, you may feel a cold sensation moving up your arm, but there are generally no other side effects. If you are swallowing a capsule, there will be little or no taste. It is important that you remain still while the images are being taken so that the best quality images can be obtained.

WHAT TO EXPECT AFTER THE NUCLEAR MEDICINE SCAN

There are no side effects, after-effects or restrictions after the scan. You may perform all activities and may take all medications after the scan is completed. The small amount of radioisotope in your body will lose its radioactivity and may also pass out of your body through urine or stool. You may drink extra fluids after the scan and void more frequently to help remove the radioisotope from your body.

WHAT ABOUT MY RESULTS?

A board-certified radiologist or a cardiologist who is certified in Nuclear Cardiology will interpret the films and a written report will be sent to the ordering physician within 48 hours. The results will also be available via internet as soon as the final report is dictated. A copy of the final report will be forwarded to the ordering physician and/or primary care physician who will discuss the results with you.

SCHEDULING TESTS

An appointment is needed for all testing in Nuclear Medicine. All scans except for cardiac perfusion stress test and lymphoscintigraphy are scheduled through Central Scheduling at extension 2006. Cardiac perfusion stress test and lymphoscintigraphy studies are booked in the Nuclear Medicine department by calling extension 2136.