Featured Research

from universities, journals, and other organizations

Duke Engineers Developing Ultrasound Devices Combining 3-D Imaging With Therapeutic Heating

Date:
November 6, 2005
Source:
Duke University
Summary:
Duke University engineers are developing technology that may enable physicians to someday use high frequency ultrasound waves both to visualize the heart's interior in three dimensions and then selectively destroy heart tissue with heat to correct arrhythmias.

Duke University engineers are developing technology that may enable physicians to someday use high frequency ultrasound waves both to visualize the heart's interior in three dimensions and then selectively destroy heart tissue with heat to correct arrhythmias.

"No one else has developed a way for ultrasound to combine therapy and imaging in a catheter, let alone 3-D imaging," said Stephen Smith, the biomedical engineering professor who heads the project at Duke's Pratt School of Engineering.

Smith's group described work that developed initial laboratory prototypes in two research papers published in October 2005 in the journal "IEEE Transactions on Ultrasonics, Ferroelectronics and Frequency Control" and the journal "Ultrasonic Imaging."

In an interview, he said his group's technique may improve on doctors' most widely used method for destroying -- or "ablating" -- aberrant tissue that makes hearts beat irregularly. That current technique employs radio waves emitted from the end of an electrode probe that touches and excessively heats tissue selected for destruction.

After threading that internal probe into the heart through arteries, physicians must now rely on fluoroscopic imaging -- X-ray movies -- to help point the device. "However, a fluoroscope cannot image soft tissue at all," Smith said. "So the heart is just a fuzzy background." Under those circumstances, fluoroscopy can provide physicians "only a very gross guidance," he added.

Duke biomedical engineers previously pioneered techniques rendering the kind of soft tissue internal images that enable fetuses to be seen in the womb. They have also pioneered the use of ultrasound to create 3-D images of the heart and other organs.

During the past five years other researchers have followed up by developing tiny internal ultrasound imaging probes than can provide physicians better visual guidance than X-rays for internal surgery, Smith said. But those previous tiny probes acquire only two-dimensional images, which still have shortcomings for pinpoint tissue ablation, he said.

Meanwhile, other researchers have separately crafted probes using stronger ultrasound waves to heat internal tissues for ablation rather than for imaging. But combining ablation with 3-D imaging in one device is new, he said.

"The nice thing about ultrasound ablation is that you don't have to touch the tissue," Smith said. "The sound waves propagate through the blood and can ablate the tissue from a distance of a centimeter or two."

His group's new work builds on its previous success at miniaturizing ultrasound 3-D imaging probes to a dime-sized array of hundreds of individual ultrasound sound sending and receiving elements, called transducers. Such probes are small enough to insert inside the esophagus to render images of the whole heart.

Smith said his team has now built dual-function imaging-plus-ablation ultrasound probes as small as three millimeters -- less than half the size of a dime. "We started using very tiny cables, fitting as many as two hundred into a three millimeter catheter," he said. "This advance in cable technology has allowed us to incorporate both 3-D imaging and ablation in the same catheter.

"The ability to build these tiny matrix arrays is a technology that we've developed at Duke for the past decade and now the ultrasound community is following in our footsteps."

In another paper prepared for an October 2003 IEEE ultrasonics symposium, Smith and his former graduate student Kenneth Gentry -- now a postdoctoral researcher at the University of Wisconsin -- described using a prototype device to first image and then raise the temperature of a tissue-mimicking rubber by 25 degrees Fahrenheit. That temperature increase was enough to ablate real tissue, he said. According to that earlier symposium paper, the prototype was also ablation tested on a piece of beef muscle and imaging tested within a fixed sheep heart.

According to Smith, the ablation beam emerging from the same 112-transducer array was 50 times more energetic than the imaging beam. "So far, we've been taking turns at imaging for an instant and than ablating in the next instant," he said.

He acknowledged that further miniaturization and other design work will be necessary to build a device small enough to be inserted through vascular pathways into real hearts for visualization and ablation trials.

"We've had the design intuition that allows us to do and describe some preliminary experiments," he said. "But we have not yet made a practical device that could even be used in a live animal."

###

Other colleagues involved in the work include Mark Palmeri, another former Pratt biomedical engineering graduate student who just received his Ph.D., and Nasheer Sachedina, a former biomedical engineering undergraduate now in medical school at the University of Miami.


Story Source:

The above story is based on materials provided by Duke University. Note: Materials may be edited for content and length.


Cite This Page:

Duke University. "Duke Engineers Developing Ultrasound Devices Combining 3-D Imaging With Therapeutic Heating." ScienceDaily. ScienceDaily, 6 November 2005. <www.sciencedaily.com/releases/2005/11/051106180548.htm>.
Duke University. (2005, November 6). Duke Engineers Developing Ultrasound Devices Combining 3-D Imaging With Therapeutic Heating. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2005/11/051106180548.htm
Duke University. "Duke Engineers Developing Ultrasound Devices Combining 3-D Imaging With Therapeutic Heating." ScienceDaily. www.sciencedaily.com/releases/2005/11/051106180548.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Portable Breathalyzer Gets You Home Safely

Portable Breathalyzer Gets You Home Safely

Buzz60 (Oct. 21, 2014) Breeze, a portable breathalyzer, gets you home safely by instantly showing your blood alcohol content, and with one tap, lets you call an Uber, a cab or a friend from your contact list to pick you up. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins