What should you know about an open MRI machine?

MRI uses a strong magnetic field and radio waves to create images; it does not use x-rays. An open design leaves more space around some or all of the body, which may help people who feel anxious in a narrow scanner. The design varies between centres, and an open scanner may not be appropriate for every examination or may produce images differently from a conventional system.

The scan itself does not diagnose cancer on its own. A radiologist interprets the images alongside your symptoms, examination and other tests. If an image shows an area that needs closer assessment, your care team may discuss another scan or a biopsy.

Tell the imaging team about metal fragments, implanted devices, clips, pumps, hearing devices, pregnancy or possible pregnancy, and previous reactions to contrast material. Remove jewellery, watches, cards and other metal items before entering the scan room. You may need to change clothes and follow instructions about food or drink if contrast or sedation is planned.

During the scan, remain as still as you can and use the call button if you need help. Ear protection reduces the tapping and knocking sounds. Ask whether you can see the machine beforehand or bring a support person to the appointment.

Contact the imaging service promptly if you develop a rash, swelling, breathing difficulty or severe dizziness after contrast. Seek urgent medical help for trouble breathing, fainting, sudden weakness, a new seizure or a severe headache. These symptoms need assessment regardless of whether an MRI is scheduled.

Ask which type of scanner is planned, whether it can answer the clinical question, whether contrast is needed, how long you should expect to remain still, and when the report will be shared. You can read more about the [MRI Scanner](/technology/mri-scanner/) and [MRI Scan](/treatments/diagnostics-and-staging/mri-scan/).