What Is an MRI Scanner Used For?

The scanner uses a strong magnetic field and radio waves rather than X-rays. It can distinguish soft tissues, such as the brain, muscles, nerves, breasts and organs, and can show the size and position of an area that needs assessment.

Depending on the clinical question, images may be taken with or without contrast material. MRI can help a team plan a biopsy or treatment, check how a tumour relates to nearby structures, and compare changes over time. The scan itself does not treat cancer.

Tell the imaging team about metal implants, a pacemaker, medication pumps, shrapnel, kidney problems, pregnancy, or a previous reaction to contrast material. Remove metal objects before entering the scanner room. Some people may need a short period without food or drink, depending on the planned examination.

During the scan, you lie still on a movable table while the machine makes loud tapping sounds. Ear protection is provided, and you can usually communicate with the team. Ask whether an open scanner or support for claustrophobia is available if enclosed spaces worry you.

Contact the imaging service promptly if you develop a new rash, swelling, breathing difficulty, severe dizziness or other concerning symptoms after contrast material. Seek urgent medical help for trouble breathing, fainting or sudden weakness. Follow the appointment instructions if pain, fever or another symptom is changing while you wait for imaging.

Ask what area will be scanned, whether contrast is planned, how long the appointment may take, and when results will be discussed. You can also ask how the findings will affect the next step in your care.