There are many advantages to having MRI physics evaluations. The procedure is noninvasive and exposes you to no radiation. While some studies require contrast dye to which some patients may have a reaction, the imaging scan itself usually produces no side effects.
Nevertheless, MRI has its own requirements. Before you have a scan performed, there are things you need to know.
1. MRI Takes Place in an Enclosed Space
Generally speaking, the MRI scan requires you to remain in an enclosed space for the duration of the study. This can make it difficult for people with claustrophobia. If you feel uncomfortable with enclosed spaces, your doctor may offer you sedation during the scan. Another option is an open MRI machine that does not subject you to enclosed spaces. These are less widespread than traditional MRI machines and may only be available for scanning certain body parts.
2. You Must Remove All Metal
MRI uses powerful magnets, so any metal on your body may interfere with the scan and potentially subject you to injury. You should remove any accessories that contain metal before the scan:
- Hearing aids
Even partial dentures may interfere with the scan and need to be removed.
You should also not wear any clothing that contains metal, such as underwire bras or jeans with zippers or rivets. Metal particles are sometimes found in cosmetics, so it is safest not to wear any make-up. Braces and fillings pose no danger but may distort images. The scan may last longer because the technician may have to take extra images for accuracy.
3. You Must Stay Completely Still
An MRI scan can take between 20 minutes and an hour to complete, depending on factors such as the body part to be scanned. During the scan you must stay completely still. Any movement will show up on the images as an artifact, and it may affect the accuracy of the study.
Following the MRI scan, you can usually return to your normal activities right away. However, if you receive sedation, you may need some time to recover.