Nuclear Medicine

Studying the function of your body

Nuclear medicine procedures, commonly called “scans,” provide information about the anatomy of the body and the function of its organs. Nuclear medicine encompasses a wide variety of diagnostic tests. With nuclear medicine, we can produce images of nearly every organ system.

Your nuclear medicine procedure has been designed and is monitored by a team of specially trained radiologists here at SIRA, pharmacists who oversee the special chemical compounds required, and technologists who perform the exams.

How does it work?

Most nuclear exams require an I.V. injection or sometimes an oral ingestion of a radiopharmaceutical. A large detector called a Gamma Camera is focused on the area we are studying, allowing us to obtain digital images.

In principle, the gamma camera can be thought of as a “reverse x-ray.” In a conventional x-ray exam, the radiation is emitted from a machine and is passed through the patient to a film or detector. In nuclear medicine, the administered radiation comes from the patient and is collected by the detector to create an image.

In general, conventional radiography is better at seeing anatomical detail, while nuclear exams are used to look at physiologic function, or how things work.

In a nuclear medicine diagnostic scan, you will be given a special chemical compound which contains a tiny amount of a radioactive isotope. You will take this either by mouth, injection, or inhalant, depending upon the sort of compound that you need. The compound will travel to the parts of your body that we need to look at and it concentrates there. When the scanner takes its pictures, it is really scanning for the radioactive isotope. The scanner itself does not emit any radiation, but your own body will!

What to expect at your appointment

Unless you are instructed otherwise by your physician, there is nothing that you have to do to prepare for the exam. Most of the exams require no preparation. You may be asked to change into a gown and your personal belongings may be kept in a locker.

You will be asked some questions about your medical history. You must tell your technologist if you are pregnant, if you may be pregnant, or if you are breastfeeding a baby.

As with any test using ionizing radiation, we avoid routine scanning of pregnant women. Any woman who is breastfeeding must refrain from nursing for at least 24 to 36 hours, depending upon the type of scan.

After the administration of the compound, you may be asked to wait a period of time before your scan begins. This waiting time will vary for different kinds of scans. Some may be performed almost immediately, while others may not take place for a number of hours or even days after you get the drug. (You don’t have to wait the whole time at our office.) This waiting period is necessary because it takes time for the compounds we use in nuclear medicine to accumulate in the part of your body being studied.

Here is a list of pre-scan procedures for some of our tests:

Bone scan: When you report, the technologist will inject the radiopharmaceutical into a vein. In 2 to 4 hours, you will return for scanning. The test itself usually takes about 45 minutes.

Cholescintigraphy (also may be called a HIDA, hepatobiliary, gallbladder ejection fraction, or biliary excretory scan): You may have nothing to eat or drink after midnight the night before your exam. Normally the exam takes about ninety minutes.

Iodine-123 thyroid uptake & scan: You must be off any thyroid medication (Synthroid, for example) for 6 weeks prior to the test) and you should not have had a recent contrast procedure using iodinated dye. These include such tests as IVP and CT with contrast. You must have nothing to eat or drink after midnight the night before your test. You will swallow a capsule and then return to the Center in about 6 hours for your scan. You must also report for more scanning the next day. If you have any questions about pre-scan procedures please call SIRA.

The risks are actually quite limited

The term “Nuclear Medicine” often awakens deep-seated fears in people, stirring up long-forgotten images of mushroom clouds and duck-and-cover drills. Because of this, many anxious patients only half-jokingly ask, “Will I glow in the dark?” The truth is that this diagnostic modality actually uses very small amounts of radiation.

The safety of nuclear medicine compares favorably to that of other diagnostic imaging tests. The amounts of radiation you get in your body from a procedure are about the same or less than that which you get from an x-ray. Our well-trained technologists and overseeing physicians make sure that everything about the procedure is as safe as possible.

Side effects to the medical compounds that you will be given are very rare and the compounds are eliminated quickly from your body.

After the exam

You may resume your normal routine of activities after your exam. If you have had to stop taking regular medicines prior to the exam, you will want to check with your doctor to see when you should start taking them again.

Results

Our nuclear medicine physician will analyze the various pictures that are taken during your scan. The physician will then compare these pictures with the results of other tests, to reach a clear diagnosis of your medical situation.