Diagnostic imaging lets your healthcare provider see what may be happening inside your body. The different types of tests include:
- Computed tomography (CT) scans
- Magnetic resonance imaging (MRI scans)
- Nuclear medicine scans
The tests are recommended based on your health condition and symptoms, what part of your body your provider needs to examine, and how urgently the test needs to be done.
Diagnostic imaging may be used to:
- Find tumors, infections, or blood clots
- Examine fractures or internal injuries due to an accident or trauma
- Determine the location and size of bleeding in the brain or another organ
- Understand what may be causing headaches, weakness, or a change in personality
- Help surgeons navigate during a procedure
In some cases, contrast (dye) is put into the blood stream or other area of the body to highlight an area of concern. A patient may also need to drink a special liquid containing contrast to show changes in the digestive tract (gut).
Some imaging tests are done with a thin tube called a scope. The scope contains a tiny light and camera and is put inside your body. This allows the doctor to get a close-up view of your blood vessels, ducts, or organs.
Diagnostic imaging tests are usually fast, painless, and accurate. In general, risks of diagnostic imaging include:
- Radiation exposure. Some imaging tests, such as x-ray, use ionized radiation to capture an image. Repeated exposure to ionizing radiation can cause cancer, but the risk is small. The benefits of the test far outweigh the risks. Ask you healthcare provider to help you understand your risk for radiation exposure.
- Allergic reaction. Contrast is a dye that is used to highlight the area being examined during certain tests. Contrast contain iodine, which can cause some people to have an allergic reaction. This is rare, but be sure to tall your healthcare provider if you’ve ever had a reaction to iodine before you have an imaging test.
Each exam is different. In general, you can expect the following:
- You may be given specific instructions on eating, drinking, or going to the bathroom before your test.
- A technician will give you instructions or help position your body during the test.
- If contrast is being used, it will be injected into a vein in your arm or into the area to be examined (your spine, for example).
- You may be asked to hold your breath. This is to help your body stay still so that clear images can be taken.
- Most tests take 10 to 60 minutes to complete.
Follow all instructions from your healthcare provider. Wear loose, comfortable clothing to your exam. You may be asked to wear a gown and to remove jewelry, piercings, eyeglasses, dentures, hearing aids, hairpins, underwire bras, or anything that may affect the quality of the image.
Tell your healthcare provider and your imaging technician about any hardware (screws, pins, or plates) you have in your body. You may be told not to eat or drink for a few hours before your test. If you have an allergy to contrast, you may need to have a steroid injection before your test to prevent a reaction.