What is mr angiography?
Magnetic Resonance Imaging (MRI) is a method of producing extremely detailed pictures of body tissues and organs without the need for x-rays. The electromagnetic energy that is released when exposing a patient to radiofrequency waves in a strong magnetic field is measured and analyzed by a computer, which forms two- or three-dimensional images that may be viewed on a TV monitor. MR angiography (MRA) is an MRI study of the blood vessels.
It utilizes MRI technology to detect, diagnose, and aid the treatment of heart disorders, stroke, and blood vessel diseases. MRA provides detailed images of blood vessels and sometimes requires a special form of contrast material that is used to make the images even clearer. The procedure is painless, and the magnetic field is not known to cause tissue damage of any kind.
how should I prepare for the procedure
The magnetic field used for MRA can possibly pull on any metal object or heat up any electronic device in the body, such as a cardiac pacemaker, vascular access port, metal plate, pins, screws or staples. You will be given a screening sheet to fill out regarding these issues. The radiologist or technologist should know about any such item and also whether you have ever had a bullet/shrapnel in your body; whether you have ever worked with metals; or if you have had a joint replacement.
If there is any question, an x-ray can be taken to detect metal objects. The radiologist should also know if you have dental fillings, braces, or dental implants in your mouth, which could distort images of the facial region or brain. You will be asked to remove hairpins, jewelry, eyeglasses, hearing aids and any dental work that can be taken out. Some wigs have metallic threads and must be removed. Red dyes used in tattoos and permanent eyeliner may contain metallic iron, but this is rarely a problem. You should report any drug allergies to the radiologist or technologist and should mention if there’s any possibility that you might be pregnant.
You can eat normally before the exam unless you are having an MRA of the Abdomen or Runoff. The rules vary at different MRI facilities, so be sure to check with your medical center about eating and drinking before the exam. Medications may be taken as usual. Some patients may feel uncomfortably confined (claustrophobic) during the exam. If you feel a sedative is necessary, you must bring a driver to your appointment. You will wear a lightweight medical gown or a set of scrubs for the exam.
how is the procedure performed
The patient is placed on a special table and positioned inside the opening of the MRI unit. A typical exam consists of five to ten imaging sequences, each taking two to 15 minutes. Each sequence provides a specific image orientation and a specified degree of image clarity or contrast. Depending on the type of exam being done, the total time needed can range from 15 to 45 minutes, not counting the time needed to change clothing, have an IV put in and answer questions. When contrast material is needed, a substance called gadolinium is given by IV injection during one of the imaging sequences. It highlights blood vessels, making them stand out from surrounding tissues. The radiologist and technologist leave the examining room during the actual imaging process, but the patient can communicate with them at any time using an intercom.
how do i get the results
After your study is over, the images will be evaluated by one of our board-certified Radiologists with expertise in MR Imaging. A final report will be sent to your doctor, who can then discuss the results with you in detail. Should you have any questions regarding your MRA scan, we will be happy to discuss them with you.