A hundred years ago, when Wilhelm Conrad Roentgen showed the world a photo of his wife's hand... with bones revealed, it was met with amazement.

But now a new type of x-ray photograph not only reveals bones... but muscle, nerves, blood vessels and cartilage flesh.

Because of the fuzzy nature of conventional x-rays, anomalies in breast x-rays are examined by two or sometimes three radiologists.

Conventional x-ray photography has depended on the absorption of x-rays in different tissues to form an image.

Dense tissue, like bones, absorbs more x-rays while soft material like flesh, absorbs less, to create an image of light and dark areas, with images of soft tissue that lack detail and appear fuzzy. But now, with a new technique, it is possible to obtain pin sharp pictures.

A team led by CSIRO's Dr Stephen Wilkins developed a method based on using a tiny point source of radiation, much smaller than is used in conventional x-ray machines.

Instead of measuring absorption, it relies on information from the bending or refraction of x-rays as they pass through tissue. And this bending or "phase shift" information forms a much sharper and magnified image.

The method relies on a tiny point, and therefore weaker, source of radiation. Because the images are sharper, a lower radiation dose may be possible, making it safer.

"We're very impressed and staggered by some of the results we've been able to achieve where we've been able to see features that are totally invisible in normal x-rays."

More accurate pictures means that subtle abnormalities are more finely portrayed, not only in medicine but also in areas such as the microelectronics and aerospace industries.

"We have a start-up company that's been formed, called x-ray Technologies, and their aim is to bring these techniques to the market place... There are so many different applications we can't possibly work on all of them at the same time."

Dr Steve Wilkins
CSIRO Materials Science
and Engineering
Private Bag 33
Clayton South MDC VIC 3169
Steve.Wilkins@csiro.au