Primary Children's Hospital


Magnetic resonance imaging (MRI) is a safe and painless test that uses a magnetic field and radio waves to produce detailed pictures of the body's organs and structures. MRI differs from CT scan in that it does not use ionizing radiation.

MRI images are created when the hydrogen atoms within the body are introduced into a magnetic field, and struck with short, precisely tuned radio waves. The reaction from theses atoms creates a slight radio wave which is picked up by a powerful antenna and sent to a computer. The computer performs millions of calculations, resulting in high resolution, cross-sectional images of the body. These images can be converted into two or three-dimensional (3-D) pictures of the area of interest. This helps doctors to pinpoint problems within the body.

MRI is used to detect a variety of conditions, including problems of the brain, spine, spinal cord, chest, abdomen, pelvis, wrists, hands, ankles, knees, feet, muscles, and joints. In some cases, it can provide clear images of body parts that can't be seen as well with an X-ray, CT scan, or ultrasound. It is particularly valuable for diagnosing problems with the eyes, ears, heart, and nervous system.

An MRI's ability to highlight contrasts in soft tissue makes it useful in deciphering problems with joints, cartilage, ligaments, and tendons. MRI can also be used to identify infections and inflammatory conditions and to rule out problems such as tumors.

Special Instructions and preps for you child's exam

In many cases, undergoing an MRI requires no special preparation. Before the exam the technician will ask your child to remove any objects containing metal, such as eyeglasses, jewelry, belts, or clothing with metal zippers or snaps. Metallic objects often produce a bright or blank spot on the images. For this reason, electronic devices are not permitted in the MRI room. Braces and dental fillings are safe, but may interfere with some scans. You will also be asked questions to make sure your child doesn't have any internal metal clips from previous surgery or anything else that might cause a problem near a strong magnetic field. If there is any chance that your child may have metal in their eyes please inform the technologist.

To obtain the highest quality MRI images, your child will need to be completely still during the scan. To help with this, your child will have the option to listen to music or watch a movie through our special MRI safe goggles. For young children who are likely to have difficulty staying still for the test, sedation medications can be given by our nurse through an IV to help them to stay asleep during the entire test. Sedation is also helpful if a child is claustrophobic.

If your child’s exam is scheduled with sedation, fasting will be required. A nurse will contact you 1 to 2 days before the procedure to give you age specific instructions for preparing your child. If you have questions and would like to speak with a nurse regarding sedation procedures please call 801-662-1870. 

MRI imaging is painless; although some studies will require an IV to be started, either to give sedation medication, or contrast solution. The exam will take approximately 30 to 90 minutes, depending on the part of the body being imaged. The technologist will place your child into position on the movable MRI scanning table. The table will slide into the MRI scanner and the technician will begin to take images. If your child feels cold while lying on the MRI table, a blanket can be provided.

You can stay in the MRI room with your child until the test begins. When the exam is about to begin, you will be asked to stay in a waiting room. The technician can talk to your child through an intercom between scans. This can soothe your child if he or she is uneasy during the MRI procedure.

Your child may need to be given a contrast solution through an IV (Watch a video on how an IV is placed). Contrast is used to highlight certain areas of interest within the body such as tissue and blood vessels, so the pediatric radiologist can see these structures with more detail. The contrast solution used for MRI is safe and painless, and allergic reactions are very rare in children. The technician will ask if your child is allergic to any medications or food before the contrast solution is given.

As the exam proceeds, your child will hear repetitive and sometimes loud sounds from the machine. These sounds are normal. Your child will be able to communicate with the technician in case he or she becomes uneasy during the test. If sedated, your child will be under the direct supervision of a nurse at all times, who will continually monitor the heartbeat, breathing, blood pressure, and oxygen level.

When the exam is over, the technician will help your child off the table; if sedation was used, your child will be moved to our recovery area where he or she will be monitored by a nurse until the affects of the sedation have worn off. Most sedation will wear off within 1 to 2 hours, and any contrast material should pass through the body in about 24 hours. Discharge instructions, emergency contact information, and follow up instructions will be given to you before you leave.

MRI images will be viewed and interpreted by a pediatric radiologist who specializes in reading images of infants and children. The radiologist will promptly send a report to your doctor, who will discuss and explain the results of your child’s test with you.

Results are usually available in 2 to 3 days. If the MRI scan was done on an emergency basis, the results can be made available more quickly. In most cases, results cannot be given directly to the patient or family at the time of the test.

MRIs are safe and easy. No health risks have been associated with the magnetic field or radio waves, since the low-energy radio waves use no radiation. The procedure can be repeated without side effects. Certain implanted medical devices such as pacemakers, shunts, implanted pumps, cochlear implants and other internal monitoring devices will need to be evaluated carefully prior to having an MRI.

You can help your child to prepare for an MRI by explaining the test in simple terms before coming to the hospital. Make sure you explain what part of the body will be examined and that the equipment will probably make knocking and buzzing noises.

If your child will be awake for the test, be sure to explain the importance of lying still. It may also help to remind your child that you will be nearby during the entire test. A short video is available to help you and your child understand an MRI.

If you have questions about the MRI procedure, please speak with your doctor. You can also talk to our Child Life Specialist, MRI technician, or the attending pediatric radiologist before the exam.

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