Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

French, Swiss Research Groups Demonstrate New "Phase" in Biological Imaging

10.08.2005


The Beginnings of a New Phase in Medical Imaging? Phase-Contrast Imaging Device Provides 3-Dimensional Views of Hard-to-Image Biological Objects



In a development that could help usher in a new kind of medical imaging for clinics and hospitals, researchers have demonstrated a practical x-ray device that provides 2- and 3-dimensional images of features in soft biological tissue that are ordinarily hard to discern with conventional x-ray imaging. Performed by researchers at the Paul Scherrer Institut in Switzerland and the European Synchrotron Radiation Facility in France, this work may help make practical new medical applications, such as the ability to detect cancerous breast tissue directly, rather than the hard-tissue calcifications that are produced in later stages of the disease. The new x-ray demonstration appears in the 8 August issue of Optics Express, an open-access journal published by the Optical Society of America.

X-rays excel at imaging hard tissue--such as teeth--as well as the differences between hard and soft tissue--such as bones and skin in the human hand. However, x-rays are not good at distinguishing between different types of soft tissue, such as normal and cancerous cells in the breast. While x-ray mammography detects the hard “calcifications” that are the byproducts of breast tumors, researchers wish to be able to detect the tumor cells directly-potentially leading to better and earlier diagnosis of breast cancer.


This is just one of the potential biomedical applications of an emerging technique called phase-sensitive x-ray imaging. Normal x-ray pictures, such as those at dental offices, are “absorption-based” images: they rely upon the fact that the teeth absorb many more x-rays than the rest of the mouth. However, soft tissue does not absorb x-rays very well, making absorption imaging unsuited to the task of capturing the details of soft structures in such organs as the breast and kidney.

Optics researchers have long known that x-rays have the potential to make detailed images of soft biological tissue through a technique known as “phase” imaging. X-rays, a form of electromagnetic wave like light, can be visualized as a series of peaks and valleys like a water wave. When an x-ray encounters the boundary of two types of material, such as normal tissue and cancerous tissue, it will undergo a “phase shift”: the peak of the wave will move backward by a small amount relative to the position where it would be if there were no sample in the beam. By measuring the phase shifts as x-rays pass through the boundaries of different kinds of tissue, researchers can obtain detailed pictures of soft biological tissue.

In a demonstration that could bring this approach much closer to medical applications, a new phase-based imaging device combines three desirable attributes-compact size (only a few centimeters in length), large field of view (up to 20x20 cm^2), and the ability to use x-rays over a broad spectrum of energies. Crucially, the design uses a pair of gratings-each a thin slab of material with narrow, closely spaced parallel lines etched deeply into them, like little slits carved into the inch marks of a ruler.

In the setup, a stream of x-rays passes through the object to be imaged and it undergoes a series of phase shifts, which distorts the stream in a precise way. The distorted x-ray stream then passes through the first grating and is diffracted; the grating slices the x-ray stream into multiple waves that combine and interfere to produce a series of fringes (bright and dark stripes). The second grating extracts from this pattern precise information on the inner details of the object (see accompanying article for more information).

Using this technique, the researchers imaged a small spider, revealing internal structures that would be difficult to image with any other method. The researchers believe that the modest requirements of this technique, both in terms of x-ray source, laboratory space, and materials, may make phase-based imaging practical for a wide range of biological and medical applications.

| alfa
Further information:
http://www.opticsexpress.org

More articles from Physics and Astronomy:

nachricht JILA researchers make coldest quantum gas of molecules
22.02.2019 | National Institute of Standards and Technology (NIST)

nachricht (Re)solving the jet/cocoon riddle of a gravitational wave event
22.02.2019 | Max-Planck-Institut für Radioastronomie

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: (Re)solving the jet/cocoon riddle of a gravitational wave event

An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.

In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

JILA researchers make coldest quantum gas of molecules

22.02.2019 | Physics and Astronomy

Understanding high efficiency of deep ultraviolet LEDs

22.02.2019 | Materials Sciences

Russian scientists show changes in the erythrocyte nanostructure under stress

22.02.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>