No X-ray dose
For people who can be scanned, MRI does not add the radiation of a CT or an X-ray. That is why it is repeated when doctors need to watch a joint, a brain or a liver lesion over time.
The real safety questions
- Pacemakers, defibrillators, cochlear implants and stimulators. Some are allowed only on strict conditions.
- Unknown metal in the eye or older aneurysm clips.
- Pregnancy, where MRI is reserved for a real question and contrast is usually avoided.
- Gadolinium, which needs caution in serious kidney disease.
The safety form is the protection. Fill it in properly, and bring implant cards. A scan that is delayed because a device could not be identified is a scan that was kept safe.