MR angiography (MRA) is a diagnostic test that uses magnetic resonance imaging (MRI) to detect major blood vessel disease and abnormality in nearly any organ or body part. MRA uses a strong magnetic field, radio frequency waves, and a computer to create images that radiologists use to diagnose problems. MRA does not use ionizing rays (X-rays), so it does not expose you to radiation. Contrast material may or may not be required for MRA, and when contrast is used it is administered intravenously.
MR angiography can detect many kinds of arterial disorders such as aneurysm, plaques, arteriovenous malformations, embolism, arterial narrowing, and other anatomic abnormalities.
Physicians also frequently order MRA in preparation for other exams or procedures to evaluate the blood supply to a specific body part, for example, in order to:
- Map arteries in preparation for arterial bypass, reconstructive surgery, or stent placement.
- Visualize the extent of arterial damage after trauma.
- Establish tumor blood supply for chemoembolization or surgical resection.
- Evaluate blood supply in preparation for organ transplant.
- MRA uses a magnetic field and radio frequency waves instead of ionizing radiation (X-rays).
- MRA is less invasive than conventional angiograms which require placing a catheter deep into the arterial blood supply. MRA eliminates the risk of artery damage. If contrast is required, it is administered through a small vein in the arm.
- The recovery time for MRA is minimal. After the scan is completed, you can resume your normal daily activities.
- An MRA exam may help you avoid exploratory surgery.
- When iodinated contrast material is not recommended, MRA can be used as a substitute exam.
- For patients with liver or kidney problems, certain MRA exams may be performed successfully without the use of any contrast material.
- Any medical devices implanted into your body may be at risk of malfunction due to the strong magnetic field. See Can I have an MRI if I have metal in my body?
- In very rare cases, in patients with poor kidney function, nephrogenic systemic fibrosis is a possible complication when contrast is used. Please refer to the About MRI Contrast section for more details.
- Gadolinium-based contrast has a very slight risk of causing an allergic reaction which can usually be easily treated.
- Pregnant women should consult with their physician prior to an MRI exam. However, there have been no documented negative effects of MRI in the many years of its medical usage, and MRI is often the method of imaging chosen for pregnant women and fetuses. It should be noted that MRI contrast agents are not recommended to be used during pregnancy unless the benefits far outweigh the risks.
- The ACR states that current information suggests breastfeeding is safe after the use of intravenous contrast. Please discuss your breastfeeding options with your medical provider.
- MRA is provided in multiple ARA imaging centers and takes a total of approximately 60 minutes.
- You will change into a gown and remove all jewelry and metal from your body.
- You’ll be placed on a moveable exam table which may have straps or bolsters to help keep your body from moving.
- A special coil that enhances the MRI signal will be placed near the parts of the body to be examined.
- If your study requires contrast, your technologist will place an intravenous (IV) line into your arm or hand to administer the contrast. IV placement may be uncomfortable and may cause bruising later but for most this is not the case. A saline solution drip may be used to help keep the IV line open.
- The technologist will leave the MRI room where you are and conduct the exam from a computer in a control room. You will be able to speak with the technologist at all times. The technologist has direct visualization of you and the room. They will keep you informed of what is happening as your exam progresses.
- When the procedure begins, the table moves you into the magnet, which is a cylinder-shaped machine.
- MRI scanners are constructed with short tunnels that are open on both ends. Most people do not find this to be uncomfortable, but if you are anxious, please mention this to your scheduler. ARA may be able to schedule your exam on one of our open-bore or short-bore MRI scanners or plan for you to have light sedation. Our clinical staff are experts at helping people through MRI exams with minimum anxiety.
- During the exam you might feel warmth in the body part being examined. If this becomes very uncomfortable, let your technologist know.
- When the images are being taken, you will hear loud knocking, tapping or thumping sounds. Earplugs or headphones with music are provided before the test begins.
- In rare cases, some patients experience side effects from the contrast material, such as nausea or headache. If you experience any discomfort, let the technologist know.
- You will be required to change into a gown. If possible, leave all jewelry and metal objects at home.
- Unless you are told otherwise, you may follow your normal diet and routine before the exam. You should take all your medications as usual.
- Some MRI exams require a prep which may include no food or drink for a specified time before the exam. Your scheduler will inform you of preparations if needed. If you are not given special instructions, you may follow your normal diet and routine before the exam.
- Ask your doctor for specific directions about your daily medications if you have been asked to refrain from taking them.
- Be sure to tell your technologist about any illness or allergies you may have. Also, provide a list of your current medications.
- Be sure to tell your scheduler and technologist if you are or might be pregnant.
- If you suffer from claustrophobia, panic attacks or anxiety, you might choose to receive sedation before the exam. Please mention this to your scheduler when making your appointment.
- Before you schedule an MRA, refer to the section Can I have an MRI if I have metal in my body? to get more information about metal devices, implants or any other metal that might be affected by the magnet.
- In some cases, an X-ray may be taken before the MRA to detect any metal that could be located inside your body.
A radiologist, a physician specifically trained to interpret radiological examinations, will analyze the images and send a signed report to the provider who referred you to ARA. The physician will then share the results with you.