Magnetic Resonance Imaging (MRI)
- Published: 27 March 2012
Magnetic resonance imaging (MRI) is primarily used in medical imaging to visualize the structure and function of the body. It provides detailed images of the body in any plane. MRI has much greater soft tissue contrast than Computed Tomography (CT) making it especially useful in neurological, musculoskeletal, cardiovascular and oncological diseases. Unlike CT, it uses no ionizing radiation. The scanner creates a powerful magnetic field which aligns the magnetization of hydrogen atoms in the body. Radio waves are used to alter the alignment of this magnetization. This causes the hydrogen atoms to emit a weak radio signal which is amplified by the scanner. This signal can be manipulated by additional magnetic fields to build up enough information to reconstruct an image of the body.