Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) uses a magnetic field and radio waves to produce cross-sectional images of the body. By taking a series of such images, MRI creates a three-dimensional view of your body, which the radiologist interprets to diagnose injury or disease. There is no exposure to x-rays.

How do I prepare for this examination?

You should follow your usual routine, eat normally, and take any regular medications. You will be asked to fill out a questionnaire, and a technologist will explain the exam to you. You must remove any metal objects, such as jewelry, watches, hairpins, glasses, dentures, or anything with metal clips or parts. You must leave any ATM or charge cards with magnetic strips outside the scanner.

Are there reasons not to have an MRI scan?

Because of the strength of the magnetic field used, the following patients should not undergo MRI scanning:

  • Patients with implanted devices such as pacemakers, internal pumps, neuro-stimulators, and middle-ear prosthesis
  • Patients who have had brain surgery for aneurysms
  • Patients with metal shavings in the eye
  • Patients with any of the above or other metal clips or objects in the body should inform the technologist before going to the scanner.

How is this procedure done?

You will be taken into a room that contains an MRI unit. You will be asked to lie down on a padded table. The table will slide forward, positioning the part of your body to be examined into the center of the magnet. You can be seen and heard during the entire scan by the technologist who monitors the exam.The MRI unit will make a slight vibration of the table and a loud tapping noise, which will come and go throughout the exam. These are normal, so don’t be alarmed. Normal test times are between 30 and 45 minutes, though some exams may take longer. The most difficult part of the procedure is lying very still. This is very important because any movement creates blurry pictures and usually longer scan times, as they need to be repeated. Occasionally a contrast agent is used, usually near the end of the procedure. This agent is injected through a vein in the arm. This helps to differentiate tissue and organs, making for a more accurate diagnosis.

When will I get the results of this test?

After completion of the study, the radiologist will carefully examine all the images before dictating a report. Your physician will receive a report within 24 to 48 hours. In order to protect confidentiality, only your doctor can relate the final results. If you have any other concerns regarding this test, please call the Radiology Department at 541-222-1700.