How Does an MRI Scan Work?
The process is entirely painless, and you won’t feel the magnetic fields or radio waves, but the machine can be noisy, making sounds like loud knocking or humming.
Magnetic Field
The MRI machine creates a powerful magnetic field around you, temporarily realigning the hydrogen atoms in your body.
Radio Waves
The machine then sends radio waves toward the aligned atoms, which causes them to produce faint signals.
Image Formation
The MRI machine detects these signals and uses a computer to convert them into detailed images of the scanned area.
Preparing for the MRI Scan
Before the scan, you may be asked to change into a hospital gown to ensure no metal is present on your clothing. All metallic items, such as jewelry, wallets, and watches, need to be left outside the MRI room since they can interfere with the machine. The MRI technician will go through a checklist with you, especially if you have any medical implants, as certain types of metal implants may not be compatible with the MRI’s magnetic field.
The MRI Scan Process
An MRI scan typically takes between 15 and 90 minutes, depending on the area being scanned and the number of images needed. Some MRI scans may require a contrast agent, injected through an IV, which makes certain tissues show up more clearly in the images. This is commonly used for brain, heart, and blood vessel scans.
Getting Positioned
Once in the MRI room, you’ll be guided to lie down on a sliding table that moves you into the machine. Depending on the part of the body being scanned, you may go entirely into the machine or partially in.
Staying Still
It’s essential to stay as still as possible during the scan because movement can blur the images. The MRI technician will communicate with you through an intercom to guide you or reassure you if needed.
Noise and Ear Protection
MRI machines can produce loud sounds during a scan, which is primarily caused by the rapid switching of magnetic coils within the machine.
Communication During the Scan
Most MRI machines have an intercom system, so you can speak to the technician if you need anything. They will also check on you periodically.
