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 Space radiation won't stop NASA's human exploration
18.10.2017 | NASA/Johnson Space Center

nachricht Study shows how water could have flowed on 'cold and icy' ancient Mars
18.10.2017 | Brown University

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>