Magnetic Resonance Imaging (MRI) is a non-invasive medical imaging technology that provides two-dimensional cross-sections from which three-dimensional information about the body can be reconstructed. You might need an MRI scan in order to diagnose problems with internal organs and tissues. It is most commonly used to collect information about brain and spinal cord damage but can also be used for other organs such as liver and heart, for example.
MRI scans are the result of several decades of technological development that ultimately led to a Nobel Prize for its creators Paul Lauterbur and Peter Mansfield in 2003. MRI is an improvement on Computed Axial Tomography (CT or CAT) scans because it allows access to information about organ chemistry and metabolism as well as to more a detailed picture of organ anatomy. MRI scans produce images of the human body using the principle of nuclear magnetic resonance of protons.
This process relies on the discovery that some nuclei only take up certain orientations when placed in a magnetic field. By aligning the protons of, typically, hydrogen atoms in the body in this way and then applying a radio wave pulse to the tissue, radio emissions can then be detected. This allows the construction of a proton density map of the body. By studying the details generated by this process a diagnosis of problems with the organ or tissue in question can then be provided.
But how does it compare to a CT scanner? A limitation of the MRI technique is that it is better suited for use in the analysis of non-calcified tissue rather than calcified tissue such as bone. This type of scan can, however, can be used in any plane, not just on the axial plane like in a CT scanner, for example. Also, MRI has adaptable functionality for achieving image contrast through changing scanning parameters.
In terms of particular problems that patients might have, MRI can be used for a variety of diagnostic tasks. One example is that of sports-related joint injuries. Other examples include the examination of inflammations and cysts, and the diagnosis of strokes. All of the organs of the body such as liver and kidneys can be analyzed using MRI. But it is the non-invasive nature of the technique that makes it particularly useful for highly sensitive areas of the body where damage through probing must be kept to a minimum. This is why it is of particularly prevalent use in diagnosing brain damage.