MRI is a fast growing imaging technique, which has been largely used for the past 20 years. For its usefulness in medical diagnosis and the monitoring of many diseases, more than 30,000 IRM systems are nowadays used all around the world. On average, every one of us would have to get 4 MRI scans in his whole life.
Magnetic Resonance Imaging is based on the combination of electromagnetic waves:
- A permanent static magnetic field (0.2 -> 7T in clinical applications);
- Some magnetic field gradients ;
- And some radiofrequency waves.
These high power electromagnetic waves generate risks for people who operate in the MRI environment. To limit, it is necessary:
- to follow the safety rules. It is necessary to train the personnel susceptible of working within the MRI environment (MRI radiographers, radiologists, surgeons, firemen, maintenance personnel…);
- and to assess the interactions between the MRI systems and the devices by MRI compatibility testing.
MRI safety and compatibility testing
Depending on its materials and geometry the devices introduced in an MRI environment may undergo large forces, warm up, vibrate or even malfunction (for active devices). These interactions generate potentially significant risks. Artifacts may also appear on the MRI images, preventing the diagnosis in the area.
Authorities require to take those phenomena into account, especially for the marketing of implantable devices or any devices potentially introduced in the MRI environment. In most cases a testing campaign should be conducted to measure each of these phenomena.