Magnetic Resonance Angiography (MRA)
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 radio 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 without using any contrast material, although today a special form of contrast usually is given to make the MRI images even clearer. The procedure is painless, and the magnetic field is not known to cause tissue damage of any kind.
Because of the strong magnetic field used for MRI, it will pull on any iron-containing object in the body. MRI staff will ask whether you have:
- A heart pacemaker or implanted defibrillator, implanted port, infusion catheter (often referred to by brand names such as Port-o-cath, Infusaport or Lifeport), intrauterine device (IUD),
- Any metal plates, pins, screws or surgical staples in your body.
- A bullet or shrapnel in your body, or ever worked with metal. If there is any question of metal fragments, you may be asked to have an x-ray that will detect any metal objects.
- Any drug allergies and whether you have undergone any surgery in the past.
MRI causes no pain, but some patients find it uncomfortable to remain still during the examination. You may hear a loud “knocking” noise during the exam, which is normal. You may bring or request earplugs. If you are pregnant, think you may be pregnant, or are breast feeding, inform the technologist before your procedure begins.
IF YOU HAVE EVER BEEN DIAGNOSISED WITH RENAL FAILURE, INFORM THE TECHNOLGOIST BEFORE THE TEST BEGINS.
For the most up to date information, visit www.radiologyinfo.org, a website dedicated to radiology information from the patient perspective.