Why Magnetic Resonance Imaging (MRI) and not Computed Tomography (CT) or Electron Beam Tomography (EBT) screening?

MRI scanning takes advantage of the natural magnetic properties of the tissues in your body. The scanner is a strong magnet that sends radio waves through the body. The magnetic tissues in the body then send a faint radio signal back. The receiver collects all those signals and the computer builds a picture of what is inside. It produces no radiation and has no cancer risk.

EBT and CT scans of the entire body are a sophisticated form of traditional X-ray technology. They take about 1000 X-rays of the body at different depths and angles over a 45 second period, and use a computer to compile these into a three dimensional image. (These are not the same as MRIs which do not expose the body to radiation). EBT may have a slightly lower dose of radiation but is still dangerous.

The leading medical manufacturers – Philips and Siemens advise the use of MRI only for total body scans. They invented the Total Imaging Matrix which is a new technique to have a precise look into the human body without the use of dangerous X-ray. The Radiation Advisory Council of NSW, Australia, the NSW Environment Protection Agency, the Royal Australian and New Zealand College of Radiologists, the Radiation Health and Safety Advisory Council of Australia and the Committee on Medical Aspects of Radiation in the Environment all say the same thing : having full-body CT or EBT scanning as a screen when you are unwell is unnecessary and even potentially dangerous.

Their reasons? These scans have a very high incidence of false positives. In other words, when the scan does find something (which can be as high as 90% of the time), it has to be investigated with further costly and often invasive procedures. The finding is usually a benign tumour, cyst or scar tissue but the person has incurred the cost and the discomfort of further tests – plus the stress of waiting for results.

These scans also have a high incidence of false negatives. That is, they may give the person a clean bill of health, even though the person may have a hidden cancer. That’s because full body CT scans are not as effective at detecting cancers as more traditional screening procedures e.g. colonoscopies to detect bowel cancer. The person may end up with a false sense of security; convinced they don’t have cancer and therefore do not need to see their doctor or have the screening procedures recommended by health authorities. The end result is that they may be putting themselves at increased risk.