One of the ways to determine if a patient has a disc herniation is with an x-ray- specifically a lumbar MRI will pin point exactly the nerve root responsible for the pain down your leg. MRI stands for Magnetic Resonance Imaging and it a very telling tool when it comes to looking at disc herniations. When looking at a lumbar spine MRI we can assess if the intervertebral disk spaces are of normal height, and the disks do not project past the posterior surface of the vertebral bodies in any segment. Here is a normal Lumbar MRI:
The patient lies inside a large, cylinder-shaped magnet. Radio waves 10,000 to 30,000 times stronger than the magnetic field of the earth are then sent through the body. This affects the body's atoms, forcing the nuclei into a different position. As they move back into place they send out radio waves of their own. The scanner picks up these signals and a computer turns them into a picture. These pictures are based on the location and strength of the incoming signals.
Our body consists mainly of water, and water contains hydrogen atoms. For this reason, the nucleus of the hydrogen atom is often used to create an MRI scan in the manner described above
History Of MRI
It was on July 3, 1977 that the first MRI exam was ever performed on a human being.
It took almost five hours to produce one image. The images were, by today's standards, quite ugly. Dr. Raymond Damadian, a physician and scientist, along with colleagues Dr. Larry Minkoff and Dr. Michael Goldsmith, labored tirelessly for seven long years to reach this point. They named their original machine "Indomitable" to capture the spirit of their struggle to do what many said could not be done.
This machine is now in the Smithsonian Institution. As late as 1982, there were but a handful of MRI scanners in the entire United States. Today there are thousands. We can image in seconds what used to take hours.