In medicine, there are different methods in diagnostics to show the internal structures of the body. In addition to ultrasound, which works with sound waves, X-rays and computed tomography (CT), which uses X-rays to generate images, magnetic resonance imaging (MRI) is a form of non-invasive diagnostics. Imaging is performed with the help of a strong magnetic field and radio waves. Studies have shown that neither the magnetic field nor the radio waves pose a risk to the patient. These primarily affect metals in or on the body, which is why they should generally be discarded before MRI imaging.
Is there radiation during an MRI?
In contrast to X-rays or computed tomography (CT), there is no radiation when imaging with MRI. MRI works with the help of a strong magnetic field and radio waves, which are therefore not harmful to the body and are not felt by the patient during an examination. That is why MRI (compared to other imaging methods) is a preferred form of examination for children and during pregnancy, among others.
Can the strong magnetic field be harmful to me?
The strong magnetic field (magnetic field strengths of up to 3 Tesla possible) is usually not harmful to the patient. It serves to align the atomic nuclei, which return to their original position at different speeds depending on the type of tissue. This process is not felt by humans and studies have shown no risks for the patient.
However, the magnetic field does affect metals that are in the body (e.g. implants) or on the body (e.g. piercings, clothing, jewelry). Depending on the size, stability and location of the metals, the magnetic field can cause considerable risks for the patient.
Attraction and movement is possible especially in small and unstable metallic structures. These can press on surrounding tissue in the body and injure it. In addition, there is a risk that implants are removed from their position by the magnetic field and are therefore no longer functional. It is also possible to cancel out the magnetic effect of individual implants (e.g. many cochlear implants use magnets). Therefore, all metallic objects should be removed or put down before an examination and possible risk factors should be discussed with the treating physician in advance.
