MRI stands for magnetic resonance imaging. It is a way of looking inside the body at tissues that wouldn’t otherwise be visible. MRI uses non-ionizing radio frequency (RF) signals. It is not an X-ray, which uses radiation to acquire its images. MRI works best for seeing non-calcified (non bone) tissue.
MRI scanners produce a series of two-dimensional cross-sections (slices) of tissue. It can also be used to show a 3-D reconstruction of the anatomy. By changing the way the tissue is scanned, tissue contrast can be altered and enhanced in various ways to detect different features.
Signal intensity changes when there are changes in the soft tissues. Sometimes the signal intensity increases. In other cases, the signal intensity decreases. Advances in MRI techniques and software has made it possible to see these signal changes.
Doctors are still studying MRIs to see if it is possible to link the degree of signal intensity with the patient’s symptoms and/or the results of treatment. Most doctors agree that signal changes indicating spinal cord compression is a sign that surgery is needed.
In the case of spinal cord compressions, the more intense the signal change, the slower the patient’s recovery and the worse the results. Less intense signal changes predicts a faster, easier recovery.