Nuclear medicine is specialized medical care that uses tiny amounts of radioactive material to diagnose or treat disease. Most commonly, the radioactive material is used to produce images of the inside of the body.
When nuclear medicine is used for imaging, tiny amounts of radioactive material are mixed into medicine that is injected, swallowed or inhaled. These medications are called radiopharmaceuticals or radiotracers. The medication goes to the part of the body that is being examined, where it emits a kind of invisible energy called gamma waves. Special cameras can take photographs or video of those gamma waves, so they also take an image of the body part where the medication is. Videos can show how the medicine is being processed by the body.
What makes nuclear medicine so useful is that it is extremely accurate. The images taken with nuclear medicine are incredibly precise, providing images down to the molecular level, so they can show disease at its earliest stages. Nuclear medicine can also show the function of body parts instead of just their structure: it can be used to see how well a heart is beating or how much oxygen lungs are holding. It is a way for doctors to see inside the body without the risks of surgery.
The word 'radioactive' can make some patients uneasy, but nuclear medicine is very safe. The amount of radiation used is very small, less than a person usually receives from simply standing outside during a normal year. It has been used successfully for more than sixty years, and is painless.
Sometimes nuclear medicine can be used not just to diagnose disease, but also to treat it. Hyperthyroidism is sometimes treated with radioactive iodine, and certain cancers are sometimes treated with targeted radiation or radioactive medications.
Nuclear medicine provides an enormous amount of information that is not available any other way. It helps patients avoid exploratory surgeries or unnecessary treatments, and it helps physicians quickly decide on the best care.
Radiologists are physicians who work with diagnostic imaging, such as x-rays and CT scans, or treatments that involve radiation. At first glance, these two fields may not seem related. However, many modern imaging techniques involve the use of radiation. There are also several different types of radiologist, including those that specialize in images and those that provide radiation treatment.
Diagnostic radiologists use medical imaging for diagnosing disease. Imaging procedures (such as x-rays, ultrasounds, and MRIs) use energy in the form of sound or radiation to create pictures of internal organs and structures.
Interventional radiologists use imaging for guiding certain minimally invasive medical procedures. A good example of this is the use of x-ray to guide catheters during angioplasty and the placement of stents in narrowed arteries.
Nuclear radiology involves the use of radioactive medication to diagnose or treat disease. Nuclear radiologists use medication that contains very small, safe amounts of radioactive material that can be detected by special machines. This allows them to gather information about how well the body is working. They can also use radioactive medications to treat certain illnesses, such as an overactive thyroid.
Radiation therapy or radiation oncology is the branch of radiology which uses radiation to treat cancer. The radiation is given at a higher dose, but it is very specifically targeted so that it only affects cancer cells.
Radiation, whether used in imaging or for treatment, is a powerful tool. Radiologists have the training and knowledge to use it safely.
What is Magnetic Resonance Imaging (MRI)?
Magnetic Resonance Imaging, or MRI, is a test that produces a uniquely detailed and high-quality picture of the inside of the body. It is done using a strong magnetic field along with radio waves. A computer then analyzes the signals given off by hydrogen within the tissues of the body and uses those signals to develop an image. It can be done on any part of the body: the brain, chest, heart, joints, abdomen, or extremities.
MRI uses no radiation, is painless, and is extremely safe. However the machine can be loud while it is running, and patients who don’t like the feeling of being in confined spaces might feel uncomfortable. MRI might also not be appropriate for patients who have certain types of metal inside their bodies such as pacemakers, shrapnel, or metal aneurysm clips.
When you arrive for your MRI, you will usually be instructed to remove your clothing and be given a gown to wear. Because MRI works using a strong magnetic field, it’s very important that you remove all metal objects from your body, including watches, earrings, hearing aids, and hair clips. Some tests require an injection of a contrast dye to help specific parts of the body show up better in the image. You will lay down on a table and usually be offered earplugs or headphones to cancel the noise from the machine. Then the table moves you through a ring, tube, or tunnel shaped machine that makes thumping, hammering sounds. It’s important to stay as still as possible to get as clear an image as possible. An MRI can take as little as 15 minutes or more than an hour, depending on the area being examined.