What is MRI?

MRI, or magnetic resonance imaging, is a way to take detailed pictures of the body using powerful magnets. Unlike other forms of imaging (such as X-ray, CT, and fluoroscopy), there is no ionizing radiation emitted from the MRI machine.

In order to create the magnetic field to take your pictures, we need to use a ton of electricity. Because an MRI machine requires so much energy, it saves on overall power usage by leaving the magnet running all the time, rather than constantly turning it on and off everyday. Therefore the magnet is always on!

The electricity flows through miles and miles of tightly wound wires (or coils) inside the MRI machine. When the electricity runs through the machine, this causes the wires to begin to vibrate, giving off those loud banging and buzzing noises that your child will hear while being scanned. The electricity moving through those wires gives off a magnetic field. The MRI technologists are able to manipulate the different frequencies emitted by the magnetic field to match frequencies in our bodies. Since hydrogen molecules are present in almost every organ of the body, we match the frequency of our machine with the frequency of our hydrogen molecules. The two frequencies now resonate together, hence the name magnetic resonance imaging. When the frequencies of your child’s body and the magnetic field are in sync, we are able to collect data and form that data into pictures of your child’s internal organs.

Tips for your child’s MRI visit:

1. Remember the magnet is always on! You cannot bring metallic objects into the MRI scanning room.  The strong magnetic force will pull the object into the scanner, making it a dangerous flying object.  If there are questions about what items are appropriate to take with you into the scanner, please feel free to ask your MRI technologist.
2. The MRI machine is loud. Cincinnati Children’s offers your child multiple options to help cope with the commotion of the scanner. Your child can watch a movie or television show, listen to the radio, or wear earplugs.
3. Small motions are a big deal. It is very important for your child to hold completely still when we are taking pictures.  We are trying to tune the magnet with your child’s hydrogen molecules (which are extremely small) and the smallest movement can have a great impact, making the pictures blurry. Please let your technologist know if there is anything he or she can do to make your child more comfortable during the scan.