CSIRO scientists have achieved a world first with a new method for taking x-ray pictures that give sharper images of soft tissue and reduce the x-ray dosage received by patients.
Dr Stephen Wilkins and his team from the Division of Materials Science and Technology, developed the method based on the capacity of materials to change the phase of the x-rays that pass through them. It can be used to get pin-sharp pictures from objects that absorb x-rays only weakly.
Conventional x-rays work because some materials absorb x-rays better than others. Bone, for example, absorbs x-rays better than skin and muscle. This is why, in ordinary x-rays, bones stand out, and soft tissues appear wispy and translucent. Sometimes, though, it's necessary to get good x-ray pictures even when differences in absorption are very small - scanning lungs for tumours for example. This is where the new technique comes in.
Until now, this kind of radiography has been possible only with sophisticated and expensive x-ray optics and very pure x-ray sources - the x-ray equivalent of a laser. But the researchers have found a way of coaxing the information needed from conventional x-ray sources.
The work provided this week's cover story for the international science magazine Nature, with a goldfish as seen in colour by the new x-ray technique. The fish x-ray shows sharply defined edges of soft-tissue structures such as ligaments, nerve canals and cartilage. These would not show up on a normal x-ray picture or would appear as poorly resolved cloudy images.
"The potential of the new technique is enormous, " Dr Wilkins said. "Apart from application in a very wide range of industrial inspection problems, it should give doctors the means for early detection of breast and lung cancers and to target treatments more precisely, using better, safer and cheaper radiography."
Digitized JPEG colour image of the goldfish available from Wendy Parsons 06 276 6615 (w) mobile 0419 208 194
Contacts: Dr Steve Wilkins 03 9542 2918 (w) 03 987 80298 (h) or Dr Andrew Tim Stevenson 03 9542 2777(w) 059 961884