Fluoroscopy is a medical imaging test that uses X-rays to obtain still and moving images of structures and processes inside the body, often with use of a contrast agent. Since the procedure is done in real-time, the movement of different organs and structures can be visualized. This allows doctors to evaluate body functions, such as the heart pumping, swallowing mechanisms, or joint motion.
The images produced by fluoroscopy can be digitalized and stored on a computer to be viewed at any time and remotely.
Fluoroscopy is essentially a continuous X-ray that creates a moving image of your body. When X-rays are transmitted through the body, a fluorescent screen captures them and transmits the information to a computer which generates images. The result is a shadow-like representation of the bones or organs being examined. Sometimes it is used to illuminate details of the part of the body being examined and it is also used to watch certain body processes in real time, giving radiologists a wealth of information.
Fluoroscopy is sometimes the imaging tool chosen by interventional radiologists, allowing them to guide tiny tools through your body to diagnose and treat conditions using minimally invasive techniques.
The radiation exposure during fluoroscopy is greater than with standard X-ray. Any radiation exposure may increase the chances for developing a cancer later in life. However, the risk of cancer due to fluoroscopy alone is statistically very small. In every case, the benefit of the study must outweigh the risks. For example, if you have a debilitating joint condition, being able to view the joint in motion with fluoroscopy is more much important than avoiding a small amount of radiation exposure.
During some longer fluoroscopy exams, the X-rays may cause burns to the skin. However, modern techniques such as pulsed radiation and image intensifiers have greatly reduced the risk of skin burn. Typically, the only procedures that are long enough to cause burns are done in life-saving situations.
Other risks depend on whether contrast material is used and the specific type of procedure. Please refer to the About Contrast section below for more information about the risks of contrast material.
If you are, or think you are pregnant, be sure to notify your provider or technologist before undergoing fluoroscopy. In general, fluoroscopy is not recommended for pregnant women. In every case, the mother’s health must be considered as well. When compared to fluoroscopy, an undiagnosed illness during pregnancy might be even more dangerous to the baby and mother.
Only when the benefits significantly outweigh the risks of the procedure should pregnant women undergo fluoroscopy. The radiation received by the unborn baby during the procedure may increase the risk for developing cancer later in life. Your medical provider and/or your radiologist may recommend another type of exam (ultrasound or MRI) to avoid exposing your baby to radiation.
Contrast agent, or “dye,” is sometimes used to improve the detail seen in fluoroscopy images. This allows radiologists to distinguish normal from abnormal conditions. Like bones, contrast material blocks the ability of X-rays to pass through the body and appears white on images. The use of contrast allows radiologists to better visualize blood vessels, internal organs, or other structures.
Side effects have been reported when using fluoroscopy contrast; however, the overall risk is very low. Your technologist is fully trained to address any side effects or allergic reactions. Talk to your medical provider about the risks of fluoroscopy contrast. If your physician recommends a CT scan, it is because the potential benefits (diagnosing or detecting disease) far outweigh the risk of side effects.
Barium is taken as a liquid which you drink to provide contrast for exams of the esophagus (throat), stomach, or small intestine. It has a chalky but not unpleasant taste.
Barium sulfate can also be given as an enema inserted into your rectum to enhance exams of the rectum or colon (large intestine). It can make you feel bloated and uncomfortable.
Occasionally, side effects happen with barium and these include cramps, diarrhea, nausea, vomiting, or constipation. In rare cases, barium sulfate can cause more serious side effects. Tell your doctor immediately if you have hives, itching, red skin, throat swelling, trouble breathing/swallowing, hoarseness, agitation, fast heartbeat, or blue skin discoloration.
Intravenous (IV) contrast using iodine
To help radiologists see certain organs, joints, or blood vessels in more detail, you may be given iodine-based contrast through an intravenous (IV) injection in a vein in your hand or arm, or an injection directly into a joint. During the injection, you may feel a sensation of warmth, a metallic taste in your mouth, or the urge to urinate. These symptoms are temporary and usually go away quickly.
Rarely, iodine-based contrast material may cause nausea, vomiting, headache, itching, flushing, skin rash, or hives, which is easily treatable with allergy medication such as Benadryl. More severe reactions are very rare and may include severe rash, breathing difficulty, abnormal heart rhythm, blood pressure abnormality, body swelling, convulsions, or cardiac arrest. Please let your medical provider and technologist know if you have had an allergic reaction to iodine in the past.
If you are to have fluoroscopy with contrast, be sure to inform your physician of all medications and allergies you may have. If you have a known allergy to contrast material, make sure you inform your medical provider before scheduling your fluoroscopy. You may be instructed to take medication (usually a steroid) up to 12 hours before the test to reduce the risk of an allergic reaction.
Inform your radiologist about any chronic medical condition or recent illness especially if you have a history of heart disease, asthma, diabetes, kidney disease, sickle cell anemia, or thyroid problems. If you have significant kidney disease or renal dysfunction, you may not be able to receive IV contrast. Discuss these issues with your medical provider as an alternative test may be recommended.
If you have kidney (renal) disease or dysfunction, you may be at higher risk for contrast-induced nephropathy (CIN). This condition occurs in patients with preexisting kidney disease that gets worse after receiving iodine-based contrast. Most cases of CIN appear to have occurred with older contrast materials that are no longer used. Some recent studies have not found an increased risk of CIN due to iodine-based contrast. If you have impaired kidney/renal function, be sure to discuss the risks of receiving contrast with your medical provider.
The American College of Radiology (ACR) says that current information suggests that breastfeeding is safe after the use of intravenous contrast. Please discuss your breastfeeding options with your medical provider.