Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bubbles go high-tech to fight tumors

24.07.2006
Bubbles: You’ve bathed in them, popped them, endured bad song lyrics about them. Now, University of Michigan researchers hope to add a more sophisticated application to the list—gas bubbles used like corks to block oxygen flow to tumors, or to deliver drugs.

The process of blocking blood flow to a tumor is called embolization, and using gas bubbles is a new technique in embolotherapy. What makes it so promising is that the technique allows doctors to control exactly where the bubbles are formed, so blockage of blood flow to surrounding tissue is minimal, said Joseph Bull, assistant professor of biomedical engineering at U-M.

The research of Bull and collaborator Brian Fowlkes, an associate professor in the Department of Radiology in the U-M Medical School, is currently focused on the fundamental vaporization and transport topics that must first be understood in order to translate this developmental technique to the clinic.

In traditional embolotherapy techniques, the so-called cork that doctors use to block the blood flow—called an emboli—is solid. For instance, it could be a blood clot or a gel of some kind. A major difficulty with these approaches is restricting the emboli to the tumor to minimize destruction of surrounding tissue, without extremely invasive procedures, Bull said. The emboli must be delivered by a catheter placed into the body at the tumor site.

Gas bubbles, on the other hand, allow very precise delivery because their formation can be controlled and directed from the outside, by a focused high intensity ultrasound.

This envisioned technique is actually a two-step process, Bull said. First, a stream of encapsulated superheated perfluorocarbon liquid droplets goes into the body by way of an intravenous injection. The droplets are small enough that they don’t lodge in vessels. Doctors image the droplets with standard ultrasound, and once the droplets reach their destination, scientists hit them with high intensity ultrasound. The ultrasound acts like a pin popping a water balloon. After the shell pops, the perfluorocarbon expands into a gas bubble that is approximately 125 times larger in volume than the droplet.

"If a bubble remained spherical its diameter would be much larger than that of the vessel," Bull said. "So it deforms into a long sausage-shaped bubble that lodges in the vessel like a cork. Two or three doses of bubbles will occlude most of the (blood) flow." Without blood flow, the tumor dies.

Because the bubble is so big, it’s critical to get the right vessel in order not to damage it.

"How flexible the vessel is plays a very important role in where you do this," Bull said. That is the subject of a paper coming out on gas embolotherapy in the August issue of the Journal of Biomechanical Engineering.

Bull’s post doctoral student Tao Ye was a co-author on the paper.

The technique could be very valuable in treating certain cancers, such as renal cancer and hepatocellular carcinoma, the most common form of liver cancer, causing about 1,250,000 deaths annually. However, cirrhosis of the liver makes it difficult to treat by the conventional method of removing the tumor and surrounding tissue, because so much of the liver is already damaged. This cancer has a high mortality rate.

Laura Bailey | EurekAlert!
Further information:
http://www.umich.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>