Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New phase-contrast microscopy developed at PSI enhances X-ray images.

10.05.2006


Innovations for society

Imaging techniques are increasingly at the forefront of progress in science and technology. The Paul Scherrer Institute (PSI) is among the leaders in this development. Imaging techniques turn objects visually inside out, allowing ever greater precision– for instance in medical diagnosis. They also contribute to a better understanding of the mechanisms of certain diseases, like Alzheimer’s or osteoporosis. Further applications occur in materials research, where imaging processes are a decisive factor in achieving results that ultimately – as with medical progress – benefit society.

The new phase-contrast microscopy developed at PSI enhances the sensitivity and contrast of classical X-ray images. Traditional techniques are based on the different X-ray absorbance of different materials, which enables the structure of dense body-matter like bones to be readily differentiated from that of lighter tissue. Low-absorbance materials, however, produce low-contrast images, which makes it difficult to visually reproduce fine details using conventional X-ray methods.

It has been discovered, however, that X-rays not only lose intensity when passing through a sample, they also undergo a phase shift, because the speed of light waves in matter differs from their speed in a vacuum. This phase shift is sensitive to the smallest changes in tissue, which means that phase signals can be used to substantially heighten the contrast of an X-ray picture.

Safer early diagnosis of breast cancer

Enhanced contrast enables the X-ray dose to be significantly reduced, which is particularly relevant to mammography techniques in screening for breast cancer. Phase-contrast microscopy is readily adaptable to existing X-ray equipment and could, therefore, trigger a major improvement in future X-ray diagnostic techniques.

Another aspect of medical technology currently at the top of PSI’s research programme is X-ray microtomography, a process that provides a detailed image of the interior of a sample. PSI results are of particularly high quality because the Swiss Light Source (SLS) particle accelerator generates X-rays of unparalleled intensity. The more intensive the X-ray beam, the better and faster the microtomography. Three dimensional images with a resolution of one thousandth of a millimeter (1 micrometer) can currently be produced within minutes.

Top quality 3D images

The PSI equipment can take snapshots of aluminum alloys, ceramics, and prehistoric embryos, as well as bones affected by osteoporosis. A joint research project of PSI, ETH Zurich, the University of Zurich and Novartis is looking for traces of Alzheimer’s disease in blood vessels. Scientists have recorded changes to blood vessels in the brains of young mice with Alzheimer’s disease. This might indicate that the -origins of the disease are connected with insufficient blood supply to the brain – in other words that the protein deposits typical of Alz-heimer’s might be caused by lack of oxygen. Achieving a resolution of 1–15 micrometers, PSI’s 3D imaging of mouse blood vessels is an important tool in researching this hypothesis.

PSI’s two neutron radiography instruments, NEUTRA and (since 2005) ICON, are basically no more than large-scale cameras. But they have special powers – they can see through objects without destroying them. So can X-ray devices; but the difference is that neutrons can do this with heavy metals like lead or uranium. And they have other advantages, too. For examining finely structured organic substances (and water) the neutron beam is definitely the instrument of choice.

Roman swords and dino vertebrae

The equipment is often used for routine jobs like the examination of welds and seams, or testing for corrosion, or for electro-chemical and geological research. But questions also come from archaeologists interested in Celtic coins or in the workmanship of Roman swords, from palaeontologists studying the cervical vertebrae of dinosaurs, and even from engineers testing bullet-proof vests.

Last year PSI spent almost SF 270 million not only on its in-house research projects, but also in academic training, and in its function as one of the top user laboratories worldwide. In 2005 a record number of more than 1400 scientists from 50 different countries used our large scale facilities for their experiments, and the number of user-visits was also substantially higher than in the previous year. The quality of PSI’s experimental facilities and equipment, as well as our advice and consultation services, is clearly a factor that attracts scientists in increasing numbers to Villigen.

Juanita Schlaepfer-Miller | alfa
Further information:
http://www.psi.ch/medien/medien_news_e.shtml

More articles from Medical Engineering:

nachricht UTSA study describes new minimally invasive device to treat cancer and other illnesses
02.12.2016 | University of Texas at San Antonio

nachricht Earlier Alzheimer's diagnosis may be possible with new imaging compound
02.11.2016 | Washington University School of Medicine

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>