What is an MRI?

female physician looks at mri scans on computer screens

The MRI machine is a large, tube-shaped machine that uses a large magnet, radiofrequencies, and computers to form two-dimensional (2D) images of the body area being studied. Cross-sectional views can be done to show more details. MRI does not use radiation, like X-rays or computed tomography (CT scans), and may be used instead of a CT scan when organs or soft tissue are being studied. An MRI may be done with or without “contrast.” Contrast refers to a substance taken by mouth or injected into an intravenous (IV) line that causes the particular organ or tissue under study to show up more clearly on the scan.

Who cannot undergo an MRI?
What information should you share before an MRI?
What happens during an MRI?
How do I find out my test results?