What is the bore size of an MRI scanner?

During an MRI, the table moves through the scanner's cylindrical opening while the selected body area is positioned within the imaging region. The bore is not the same as the table width or the room around the machine. Space can also feel different depending on the body coil, padding and the position needed for your examination.

Some scanners have a wider opening or a shorter tunnel, while others are designed for particular examinations. A wider opening does not automatically suit every body area or provide the same image quality for every question. The radiology team chooses equipment and positioning according to the examination requested.

When booking, ask the centre for the scanner's bore dimensions, table weight limit and the space required for the body part being examined. Share any concerns about body size, shoulder width, pain when lying flat or difficulty entering enclosed spaces. Staff can advise whether another scanner, position or centre may be appropriate.

Wear clothing without metal and follow instructions about food, drink and medicines. During the scan, you can communicate with the radiographer and use an alarm button. Practise slow breathing and agree on a signal if you need the scan paused.

Contact the imaging centre before arriving if you are unsure that the table or bore will accommodate you; this allows a safe plan to be made. Seek urgent medical care for sudden weakness, a seizure, severe breathing difficulty or a sudden severe headache rather than waiting for a routine MRI appointment.

Ask which scanner will be used, whether your body area needs a coil, and whether the table has a stated weight limit. Ask what support is available for claustrophobia, whether a support person can be present, and whether another imaging option could answer the same clinical question.