Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ultrasound for open leg ulcers

05.12.2007
For skin transplants to “take root”, it needs to be ensured that the patient’s tissue is properly irrigated with blood. Low-frequency ultrasound can promote this effect. Researchers have developed the first device that permits variable control of the ultrasound frequency.

Minor skin wounds might hurt a lot, but they usually heal within a matter of days. For diabetics, the slightest scratch can have more serious consequences. In many cases the wound takes a long time to heal and spreads to the entire lower leg: Specialists refer to this as an “open leg ulcer”. The main reason is poor circulation, which causes insufficient oxygen and other nutrients to be transported to the wound.

In many cases, the only solution is a skin transplant of healthy tissue. To ensure that the transplant is accepted, the surgeon has to clean the wound and artificially stimulate the blood flow in the surrounding tissue – often using low-frequency ultrasound. Unlike the ultrasound used in prenatal examinations, which operates at frequencies of several hundred kilohertz, the frequencies used here are measured in tens of kilohertz. Devices operating at fixed frequencies are already available. But what effect does the treatment have on the patient’s circulation? The only empirical data that exists at present is based on patient surveys.

Researchers at the Fraunhofer Institute for Machine Tools and Forming Technology IWU in Dresden teamed up with colleagues from IMM Ingenieurbüro Mittweida and Smart Material GmbH Dresden to carry out a systematic study of this method. How often, for how long, and at what frequencies do wounds have to be treated to prepare them optimally for transplantation?

“We have developed a device that permits the frequency of the ultrasound waves to be varied between 20 and 120 kilohertz, and also has an output regulator,” says IWU team leader Dr. Gunther Naumann. “To stimulate the blood flow in the deeper epidermal layers, we need a lower frequency than that required to clean the wound in the subcutaneous zone.”

Another unique feature of the new ultrasound device is that it is equipped with a measuring system that directs light into the wound using special probes. The red region of the color spectrum of the reflected light indicates the concentration of oxygen in the blood – which in turn reveals how efficiently the tissue is being irrigated.

“Our observations have shown that the oxygen concentration continues to rise for 30 minutes after treatment. But we need to conduct further investigations to determine whether a sustained higher level can be reached after repeated treatment,” Naumann reports.

A prototype of the new device has been installed for use in clinical trials in the Department of Dermatology and Allergology at the academic teaching hospital in Dresden-Friedrichstadt. Ten patients have been treated so far. The study is to be continued in 2008.

Press Office | alfa
Further information:
http://www.fraunhofer.de
http://www.fraunhofer.de/EN/bigimg/2007/md12fo3g.jsp
http://www.fraunhofer.de/EN/bigimg/2007/md12fo3g2.jsp

More articles from Medical Engineering:

nachricht Smartphones as ophthalmoscopes save sight: Cost-effective telemedical eye screening of people with diabetes in India
09.07.2019 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Shorter courses of proton therapy can be just as effective as full courses prostate cancer
08.07.2019 | University of Pennsylvania 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: Megakaryocytes act as „bouncers“ restraining cell migration in the bone marrow

Scientists at the University Würzburg and University Hospital of Würzburg found that megakaryocytes act as “bouncers” and thus modulate bone marrow niche properties and cell migration dynamics. The study was published in July in the Journal “Haematologica”.

Hematopoiesis is the process of forming blood cells, which occurs predominantly in the bone marrow. The bone marrow produces all types of blood cells: red...

Im Focus: Artificial neural network resolves puzzles from condensed matter physics: Which is the perfect quantum theory?

For some phenomena in quantum many-body physics several competing theories exist. But which of them describes a quantum phenomenon best? A team of researchers from the Technical University of Munich (TUM) and Harvard University in the United States has now successfully deployed artificial neural networks for image analysis of quantum systems.

Is that a dog or a cat? Such a classification is a prime example of machine learning: artificial neural networks can be trained to analyze images by looking...

Im Focus: Extremely hard yet metallically conductive: Bayreuth researchers develop novel material with high-tech prospects

An international research group led by scientists from the University of Bayreuth has produced a previously unknown material: Rhenium nitride pernitride. Thanks to combining properties that were previously considered incompatible, it looks set to become highly attractive for technological applications. Indeed, it is a super-hard metallic conductor that can withstand extremely high pressures like a diamond. A process now developed in Bayreuth opens up the possibility of producing rhenium nitride pernitride and other technologically interesting materials in sufficiently large quantity for their properties characterisation. The new findings are presented in "Nature Communications".

The possibility of finding a compound that was metallically conductive, super-hard, and ultra-incompressible was long considered unlikely in science. It was...

Im Focus: Modelling leads to the optimum size for platinum fuel cell catalysts: Activity of fuel cell catalysts doubled

An interdisciplinary research team at the Technical University of Munich (TUM) has built platinum nanoparticles for catalysis in fuel cells: The new size-optimized catalysts are twice as good as the best process commercially available today.

Fuel cells may well replace batteries as the power source for electric cars. They consume hydrogen, a gas which could be produced for example using surplus...

Im Focus: The secret of mushroom colors

Mushrooms: Darker fruiting bodies in cold climates

The fly agaric with its red hat is perhaps the most evocative of the diverse and variously colored mushroom species. Hitherto, the purpose of these colors was...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

Tracking down climate change with radar eyes

17.07.2019 | Earth Sciences

Researchers build transistor-like gate for quantum information processing -- with qudits

17.07.2019 | Information Technology

A new material for the battery of the future, made in UCLouvain

17.07.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>