One of the finest examples of man’s ability to build incredible things in good time is the MRI. Yes, the Magnetic Resonance Imaging machine, that round machine in an enclosed room that generates images of the inside of your body that your doctor will use to tell you how bad your tug-of-war injury really is (Yes, we really got a case recently of an arm with Clinical History: “H/o Tug of War”). The MRI is a pretty incredible piece of engineering, that went from concept to full-fledged product in just over a decade, and has since gone on to revolutionized diagnosis. With this post, we want to give you an understanding of the history and clear the mystery behind the magic of the MRI.

Magnetic resonance imaging (MRI) is a medical imaging technique that uses magnetism and radio waves to produce images of the anatomy and the physiological processes of the body. It is used to find problems such as tumors, bleeding, injury, blood vessel diseases, pinched nerver and infection (just to name a few). It can be used to provide further information for the results of an X-ray, ultrasound scan or CT scan. Over 25000 scanners are estimated to be in use worldwide.

Didn’t pay attention in Physics? No Problem!

MRI works on the principle called Nuclear Magnetic Resonance (NMR), which was independently discovered in 1946 by Felix Bloch, a Swiss physicist and Edward Mills Purcell, an American physicist (both were awarded the Nobel Prize for their discovery in 1952). The concept is quite simple actually: every material has some protons (positively charged ions) that align itself in the presence of a magnetic field, just like a bar magnet. Alignment excites these protons and on release of the field, they release some energy, which can be measured and used to determine the type of material. NMR was primarily used to study the molecular structure of a pure material and the composition of the mixture. Then came along American physicist and pioneer of Magnetic Resonance Imaging, Hermann Y. Carr, who described the first technique that could produce a one-dimensional MR image in his doctorate thesis in 1952.

Great, understood NMR. But what about MRI??

The above question is on your mind, isn’t it? But 5C always has you covered, in Teleradiology or on this blog!

MRI creates a strong magnetic field and the small biological “magnets” in the human body consisting of protons located in the nucleus of the hydrogen atom are magnetized. The proton possess fundamental magnetic properties.

First, MRI creates a steady state of magnetism within the human body by placing the body in a steady magnetic field. Second, the MRI stimulates the body with radio waves to change the steady-state orientation of protons. Third, the MRI machine stops the radio waves and registers the body’s electromagnetic transmission. Fourth, the transmitted signal are used to construct internal images of the body by computerized axial tomography.

An MRI image is not a photograph. It is actually a computerized map or image of radio signals emitted by the human body. MRI is superior to CAT scan because CAT scan is using ionizing radiation, MRI uses harmless radio waves. The only unusual preparation is that all removable metallic objects must be left outside the scanning room, including removable hearing aids, dentures and other prosthetic devices. Credit cards can be damaged by the MRI because magnetic codes can be affected by the MRI magnet.

Back to The History, and Impact of course

In 1971, an American physician Raymond Damadian found that the hydrogen nuclei of water in cancer tissue and healthy tissue showed a difference in relaxation time. Hence cancer and the normal tissue could be differentiated using nuclear magnetic resonance, and this was the beginning of the MRI revolution in human disease diagnosis.

Due to all the technology required (there’s a lot that goes on… Superconductors and what not. Why do you think it costs a few Crore Rupees?), the first human MRI wasn’t done till 1977, and since then, with the help of developments in processing power, MRI flourished. By 1987, realtime MR Imaging of the Heart was a reality.

5C as a diagnostics company truly understands the immense role that MRI has had in helping patients with faster and more accurate diagnosis. 5C has supported several critical MRIs, which have lead to immediate isolation of the problem and treatment which saved lives. Is that magic? It truly is.