Overview & Description
Magnetic Resonance Imaging, also called MRI, is a noninvasive imaging technique. Somewhat like an x-ray, it is used to view organs, soft tissue, bone, and other internal body structures. In an abdominal MRI, the person's body is exposed to radio waves while in a magnetic field. Cross-sectional pictures of the abdomen are produced by the energy given off from hydrogen atoms in the body's cells. A person is not exposed to harmful radiation during this test.
liver
spleen
pancreas
kidneys
bladder
prostate
reproductive organs
adrenal glands
abdominal blood vessels
This test may be recommended:
to look for benign or cancerous tumors or lesions
to look for abnormal or damaged organs and other tissues
to see how tumors are responding to treatment
to clarify the results of other imaging tests, such as ultrasound or abdominal CT scans
if other imaging tests or certain contrast agents should not be used
People who have certain medical devices and pieces of metal, such as pins or screws in bones or other implants, may not be able to have an MRI. Metal interferes with the magnetic field. Tattoos may cause problems, too. And MRI is not usually done during pregnancy. All of these issues should be discussed with the person's doctor or a specialist in imaging techniques called a radiologist.
has any drug allergies or history of allergic reaction to medicines
is allergic to shellfish, or foods with added iodine such as table salt
has experienced claustrophobia, or anxiety in enclosed spaces. If this is a problem, mild sedating medicine may be given.
A woman will also be asked if she might be pregnant.
As the test begins, the person lies on a flat platform. The platform then slides into a doughnut-shaped magnet where the scanning takes place. To prevent image distortion on the final images, the person must lie very still during the entire test.
Most often, a special dye called a contrast agent is given prior to or during the test. The contrast agent is used to enhance internal structures and improve image quality. Most often, this dye is injected into a vein in the arm.
The scanning process is painless. However, the part of the body being scanned may feel a bit warm. This feeling is harmless and to be expected. The person hears loud banging and knocking noises during many stages of the exam. Earplugs are provided for people who find the noises disturbing.
After the test, the person is asked to wait until the images are viewed to see if more images are needed. If the pictures look OK, the person can leave.
Who is a candidate for the test?
An abdominal MRI may be done to check organs and other tissues in the abdomen, including the:This test may be recommended:
People who have certain medical devices and pieces of metal, such as pins or screws in bones or other implants, may not be able to have an MRI. Metal interferes with the magnetic field. Tattoos may cause problems, too. And MRI is not usually done during pregnancy. All of these issues should be discussed with the person's doctor or a specialist in imaging techniques called a radiologist.
How is the test performed?
Before the test, the doctor will ask if the person:A woman will also be asked if she might be pregnant.
As the test begins, the person lies on a flat platform. The platform then slides into a doughnut-shaped magnet where the scanning takes place. To prevent image distortion on the final images, the person must lie very still during the entire test.
Most often, a special dye called a contrast agent is given prior to or during the test. The contrast agent is used to enhance internal structures and improve image quality. Most often, this dye is injected into a vein in the arm.
The scanning process is painless. However, the part of the body being scanned may feel a bit warm. This feeling is harmless and to be expected. The person hears loud banging and knocking noises during many stages of the exam. Earplugs are provided for people who find the noises disturbing.
After the test, the person is asked to wait until the images are viewed to see if more images are needed. If the pictures look OK, the person can leave.
Preparation & Expectations
What is involved in preparation for the test?
A person may be told not to eat or drink for 6 hours before the test. Specific instructions from the imaging center or radiologist may differ, though, and should be followed.Some people find it helpful to bring earplugs or ask for a special set of headphones to wear during the MRI. This muffles clicks and banging noises.
Results and Values
What do the test results mean?
After a radiologist analyzes the test results, a report is sent to the person's doctor. He or she should then discuss the results with the person who had the test.Attribution
Author:Francesca Coltrera, BA
Date Written:
Editor:Crist, Gayle P., MS, BA
Edit Date:09/30/02
Reviewer:Lanita Dawon, MD
Date Reviewed:08/20/01
American Medical Association Health Insight. "Magnetic resonance imaging (MRI)." www.ama-assn.org/insight.
Berkenblitt R. "Open MRI rises to challenge of abdominal imaging." Diagnostic Imaging Supplement, Open MRI; October 1999. www.digmag.com.
Beth Israel Deaconess, Harvard Medical School. "MRI scans (magnetic resonance imaging)." www.radiology.bidmc.harvard.edu.
Pagana KD, Pagana TJ. Mosby's Diagnostic and Laboratory Test Reference, 4th ed. St. Louis, MO: Mosby, Inc., 1999.
Date Written:
Editor:Crist, Gayle P., MS, BA
Edit Date:09/30/02
Reviewer:Lanita Dawon, MD
Date Reviewed:08/20/01
Sources
American College of Radiology and Radiological Society of North America. "MR Imaging (MRI)-Body." www.radiologyinfo.org.American Medical Association Health Insight. "Magnetic resonance imaging (MRI)." www.ama-assn.org/insight.
Berkenblitt R. "Open MRI rises to challenge of abdominal imaging." Diagnostic Imaging Supplement, Open MRI; October 1999. www.digmag.com.
Beth Israel Deaconess, Harvard Medical School. "MRI scans (magnetic resonance imaging)." www.radiology.bidmc.harvard.edu.
Pagana KD, Pagana TJ. Mosby's Diagnostic and Laboratory Test Reference, 4th ed. St. Louis, MO: Mosby, Inc., 1999.
