Scientists have developed an X-ray imaging method that could
drastically improve the contrast of computed tomography (CT)
scans whilst reducing the radiation dose deposited during the
scan. The new method is based on the combination of the high
contrast obtained by an X-ray technique known as grating
interferometry with the three-dimensional capabilities of CT. It
is also compatible with clinical CT apparatus, where an X-ray
source and detector rotate continuously around the patient
during the scan. The results are published in Proceedings of the
National Academy of Sciences (PNAS) dated June 4-8, 2012. The
conventional way of producing X-ray images is to shine an X-ray
beam on the investigated object and measure the transmitted
intensity behind it. This is the method that W.C. Röntgen
developed in 1895, just after he discovered X-rays. To the
present day, it is commonly used, for example, in hospitals and
for security screening at airports. However, since this
technique relies on variations in how the differ