Magnetics Resonance Imaging

Magnetic resonance imaging (MRI) is the diagnostic tool that currently offers the most sensitive non-invasive way of imaging the brain, spinal cord, or other areas of the body. It is the preferred imaging method to help establish a diagnosis of MS and to monitor the course of the disease. MRI has made it possible to visualize and understand much more about the underlying pathology of the disease.

Benefits

• MRI is a noninvasive imaging technique that does not involve exposure to ionizing radiation.
• MR images of the soft-tissue structures of the body—such as the heart, liver and many other organs— is more likely in some instances to identify and accurately characterize diseases than other imaging methods.

How it works

Unlike a computed tomography (CT) scan or conventional X-ray, MRI does not use radiation. Instead, MRI uses magnetic fields and radio waves to measure the relative water content in tissues — both normal tissue and abnormal — in the body . MRI works in the following way:

1. A very strong magnetic field causes a small percentage of the hydrogen protons in water molecules to line up in the direction of the magnetic field. The percentage lined up is small, but large enough to give a strong signal for imaging.
2. Once the hydrogen protons have been lined up, radio waves and some additional but weaker magnetic fields are used to knock them out of line.
3. When the radio waves are stopped, the protons relax back into line. As they relax, the protons release resonance signals that are transmitted to a computer.

The Inventor of MRI is Raymond Vahan Damadian

Cite: http://www.nationalmssociety.org/Symptoms-Diagnosis/Diagnosing-Tools/MRI