Magnetic resonance imaging (MRI) is a technique that uses a magnetic field and radio waves to create detailed images of the organs and tissues within your body.
Most MRI machines are large, tube-shaped magnets. When you lie inside an MRI machine, the magnetic field temporarily realigns hydrogen atoms in your body. Radio waves cause these aligned atoms to produce very faint signals, which are used to create cross-sectional MRI images — like slices in a loaf of bread.
The MRI machine can also be used to produce 3-D images that may be viewed from many different angles.
MRI is a noninvasive way for your doctor to examine your organs, tissues and skeletal system. It produces high-resolution images that help diagnose a variety of problems.
MRI is the most frequently used imaging test of the brain and spinal cord. It’s often performed to help diagnose:
An MRI may be used to check for tumors or other abnormalities of many organs in the body, including the:
MRI may be used to help evaluate:
The presence of metal in your body may be a safety hazard or affect a portion of the MRI image. Before receiving an MRI, tell the technologist if you have any metal or electronic devices in your body, such as:
MRI images are stored as electronic data files and usually reviewed on a computer screen. A radiologist interprets these images and sends a report to your doctor within a 48 hour period.