by Staff Writers
Karlsruhe, Germany (SPX) Mar 19, 2014
How does the hip joint of a crawling weevil move? A technique to record 3D X-ray films showing the internal movement dynamics in a spatially precise manner and, at the same time, in the temporal dimension has now been developed by researchers at ANKA, KIT's Synchrotron Radiation Source.
The scientists applied this technique to a living weevil. From up to 100,000 two-dimensional radiographs per second, they generated complete 3D film sequences in real time or slow motion.
Three-dimensional radiographs represent internal structures, but do not provide any information about movement sequences. Conventional computer tomography is not efficient enough to reproduce movement in a spatially precise manner and, at the same time, in the temporal dimension.
Every individual three-dimensional image, called tomogram, is reconstructed from hundreds of two-dimensional radiographs. "To produce highly resolved tomograms at such recording speed, we had to adjust every setting screw, from the X-ray source to the pixel detector and we optimally attuned all process steps to each other," Tomy dos Santos Rolo says.
The doctoral student is the leading developer of the experimental setup. By making the 3D image frequencies approach the image rates known for 2D cine films, he reached the world record in high-speed tomography, i.e. a real 3D film with microscopic magnification.
For scientific evaluation, the three-dimensional contours of anatomic structures have to be clearly visible. This is achieved by the so-called phase contrast. If highly parallel X-rays pass the biological examination object, wave optics phenomena occur, which highlight the inner and outer contours.
"It is these contours that matter to us. We want to distinguish individual functional elements that move relative to each other. That is why we need sharp contours," Alexey Ershov, the expert for image analysis in the team, says.
From the X-ray source to movement analysis, all process stages are designed to filter out image noise without reducing contrast. This also applies to the mathematic algorithms optimized for radiography. They reconstruct three spatial and one temporal dimension and derive exact movement patterns from the data.
In line with the first moving images - cinematography -, the scientists call their method "cinetomography". In the late 19th century, movements of big animals were studied. Today, researchers can analyze internal biological processes of small organisms, as is now demonstrated for the recently discovered screw joint of the weevil. Insects, spiders, and crustaceans make up more than 80% of all species.
Cinetomography cannot only be used to image in four dimensions biological and biotechnological processes, but also combustion processes relevant to industry.
Tomy dos Santos Rolo, Alexey Ershov, Thomas van de Kamp, and Tilo Baumbach: In vivo X-ray cine-tomography for tracking morphological dynamics, PNAS Early Edition (2014), DOI: 10.1073/pnas.1308650111
Karlsruhe Institute of Technology
Space Technology News - Applications and Research
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.|