What’s an MRI (Magnetic Resonance Imaging)?

An MRI (magnetic resonance imaging) is a safe and painless test that uses magnets and radio waves to make detailed pictures of the body's organs, muscles, soft tissues, and structures. Unlike a CAT scan, an MRI doesn’t use radiation.

MRIs are done in hospitals and at radiology centers. Help your child prepare for an MRI by explaining the test in simple terms. Talk about what part of the body will be scanned and explain that the equipment will probably make knocking and buzzing noises.

What Happens Before an MRI?

Often, an MRI needs no special preparation. Metallic objects can heat up and be dangerous in an MRI, so your child will remove anything with metal, such as eyeglasses, jewelry, belts, or piercings. Electronic devices are not permitted in the MRI room. Braces and dental fillings won't be affected by the scan.

You'll be asked if your child has any internal metal clips from previous surgery or anything else that might cause a problem near a strong magnetic field.

Tell the MRI technician if your child has an illness or allergy, has had previous drug reactions, or is pregnant.

You can stay in the MRI room with your child until the test begins. In some centers, parents can stay during the test. Otherwise, you’ll join the technician in a nearby room or stay in a waiting room. Often, parents can watch through a window and talk to their child through an intercom during breaks between scans. This can soothe kids if they’re awake in the MRI machine.

Does My Child Need Sedation for an MRI?

To get the best MRI results, kids must stay completely still during the scan. So some might need sedation, especially infants and young kids who might have trouble holding still. They’ll need to stop eating or drinking before the test to make sure the stomach is empty. 

Kids usually get sedation medicines through an IV line and will sleep during the entire test. Sedation also can help kids who are claustrophobic (afraid of close spaces). To relieve anxiety before and during the test, some patients take an oral sedative beforehand.

Kids who get sedation are monitored by a machine that checks their heartbeat, breathing, and oxygen level throughout the MRI.

If sedation is recommended for your child, discuss its risks and benefits with your doctor.

What Is Contrast Solution?

To detect specific problems, your child might get a contrast solution through an IV line. The solution is painless as it goes into the vein but can feel cold. It highlights certain areas of the body, such as blood vessels, so doctors can see them in more detail.

The contrast solution is safe for most people, but rarely, allergic reactions can happen. Talk to your doctor about the benefits and risks of its use. Before the scan, the technician will ask if your child is allergic to any medicines or food. The MRI site should have medical staff who know how to handle an allergic reaction.

If your child has decreased kidney function, be sure to discuss this with the radiologist and technician before your child gets contrast solution, as it can cause some rare complications.

What Happens During an MRI?

In most MRIs, the scanner consists of a large donut-shaped magnet with a tunnel in the center. This is sometimes called a “closed MRI.” Patients lie on a table that slides into the tunnel. Some centers have MRI scanners with larger openings (an “open MRI”), which are helpful for patients who don’t like tight spaces.

The technician will get your child into the right position on the table. After the table slides into the tunnel, the technician will take images. 

Repetitive sounds from the machine are normal. Your child might get headphones to listen to music or earplugs to block the noise and can use a call button in case they get uneasy during the test.

Your child will have to lie still on the MRI table for 20-90 minutes, depending on the test. If they feel cold lying on the MRI table, your child can ask for a blanket.

If your child has a brain MRI, a special plastic device called a coil may be placed around their head. This looks a little like a helmet and will help your child keep the head still.

When the exam is over, the technician will help your child off the table. If your child had sedation, they might go to a recovery area. Most sedation wears off within 1-2 hours. Contrast material, if used, should pass through the body in about 24 hours.

Unless sedation was used or you're told otherwise, your child can return to normal routines and diet right away.

When Are Test Results Ready?

MRI images are viewed by a radiologist who's specially trained in reading and understanding the scans. The radiologist will send a report to your doctor, who will discuss the results with you and explain what they mean. In most cases, results can't be given directly to the patient or family at the time of the test.

Are There Any Risks From MRIs?

MRIs are safe and easy. No health risks are associated with the magnetic field or radio waves, since the low-energy radio waves use no radiation. The scans can be repeated without side effects.

What if I Have Questions?

If you have questions about the MRI or the results of the test, speak with your doctor. You can also talk to the MRI technician before the exam.