Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New method of using nanotube x-rays creates CT images faster than traditional scanners

07.08.2006
Scientists at the University of North Carolina at Chapel Hill have developed a new method to create computed tomography (CT) images using carbon nanotube x-rays that works much faster than traditional scanners and uses less peak power.

The work is another step toward developing scanners for medical imaging and homeland security that are smaller, faster, and less expensive to operate, said Dr. Otto Zhou, Lyle Jones Distinguished Professor of Materials Science, in the curriculum in applied and materials sciences and the department of physics and astronomy, both in UNC's College of Arts and Sciences.

"The current CT scanners take images sequentially, which is slow and inefficient. Using the nanotube x-ray technology, we show in this paper the feasibility of multiplexing - taking multiple images at the same time," Zhou said.

Carbon nanotubes, made of layers of carbon atoms, can be as small as one nanometer - one billionth of a meter - in diameter. The UNC team uses them in this work because they can emit electrons without high heat.

The new development is published in the current edition of the journal Applied Physics Letters. The lead author of the paper is Dr. Jian Zhang, a postdoctoral research associate in the UNC School of Medicine's department of radiation oncology. In addition to Zhou, other authors - all from UNC - are Dr. Sha Chang, associate professor of radiation oncology; doctoral candidate Guan Yang and Dr. Jianping Lu, professor of condensed matter physics, both of the department of physics and astronomy; and Dr. Yueh Lee, an intern at the medical school and an adjunct assistant professor in physics and astronomy.

Traditional CT scanners use a single x-ray source that takes approximately 1,000 images from multiple angles by mechanically rotating either the x-ray source or the object being scanned at high speed.

In 2005, Zhou and colleagues created a scanner with multiple x-ray sources, called a multipixel scanner. The machine required no mechanical motion but switched rapidly among many x-ray sources, each taking an image of the object from a different angle in fast succession.

The team's newest innovation combines this multiple-x-ray-source innovation with a principle called multiplexing, in which all the x-ray sources are turned on simultaneously to capture images from multiple views at the same time.

"Let's take a simple case where suppose you need 10 images," Zhou said. "Let's say each view take one second. In the conventional step-and-shoot method used for the current CT scanners, you take one shot, and the first pixel stays on for one second. Then we turn on the second pixel, and that stays on for one second." The whole process would take 10 seconds.

"With multiplexing, we can have all the x-ray pixels on at the same time for maybe 2 seconds. You still get all the images, only faster, and we need only about half of the original x-ray peak power," Zhou said.

Multiplexing is a known concept used by, for instance, cellular phones. Millions of cell phone signals travel along the same frequency band, then are separated into coherent messages at their destinations.

"What makes the multiplexing CT scanning possible is the novel multi-pixel x-ray source we developed and the ability to program each x-ray pixel electronically," Zhou said.

In this study, Zhou and colleagues took images of a computer circuit board using a prototype multiplexing scanner, then compared the images to those generated by a traditional x-ray scanner. The images showed little difference in resolution or clarity, but the prototype multiplexing scanner got the job done faster.

"For this paper we built a prototype or demonstration scanner that gives a limited number of views, to image a simple object," Zhou said. "Our next step is to develop a small CT scanner for small animal imaging."

The work was funded by the National Cancer Institute (through the Carolina Center of Cancer Nanotechnology Excellence) and the National Institute of Biomedical Imaging and Bioengineering (both part of the National Institutes of Health); the Transportation Security Administration; and Xintek, Inc.

Clinton Colmenares | EurekAlert!
Further information:
http://www.unc.edu

More articles from Medical Engineering:

nachricht 3-D visualization of the pancreas -- new tool in diabetes research
15.03.2017 | Umea University

nachricht New PET radiotracer identifies inflammation in life-threatening atherosclerosis
02.03.2017 | Society of Nuclear 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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>