MRI scanners use strong magnetic fields, radio waves, and field gradients to generate images of the organs in the body. While the hazards of x-rays are now well-controlled computed body tomography with mri correlation pdf most medical contexts, MRI still may be seen as superior to CT in this regard. MRI is widely used in hospitals and clinics for medical diagnosis, staging of disease and follow-up without exposing the body to ionizing radiation.
MRI often may yield different diagnostic information compared with CT. There may be risks and discomfort associated with MRI scans.
Compared with CT scans, MRI scans typically take longer and are louder, and they usually require that the subject enter a narrow, confining tube. In addition, people with some medical implants or other non-removable metal inside the body may be unable to undergo an MRI examination safely. Certain atomic nuclei are able to absorb and emit radio frequency energy when placed in an external magnetic field.