Featured Research

from universities, journals, and other organizations

MEMS thermal sensor detects pre-atherosclerotic lesions

Date:
March 7, 2011
Source:
Springer Science+Business Media
Summary:
New method could sensitively detect pre-atherosclerotic regions that otherwise showed no clinical signs of atherosclerosis.

MEMS Thermal Sensor.
Credit: Dr. Tzung Hsiai,USC

A new study published in the Annals of Biomedical Engineering shows that a MEMS thermal sensor deployed by an angiogram catheter can detect the earliest stages of atherosclerosis. The MEMS thermal sensor used convective heat transfer to detect pre-atherosclerotic regions of arteries that otherwise showed no clinical signs of atherosclerosis. Although diet and lifestyle changes can often reverse atherosclerosis in its earliest stages, no real-time means of detecting pre-atherosclerotic regions exists. The MEMS sensor method has the advantage of being both minimally invasive and sensitive. The technology has the potential for widespread and rapid application during diagnostic angiograms.

The study's lead author, Dr. Tzung Hsiai, an Associate Professor of Biomedical Engineering and Cardiology at the University of Southern California, said, "The innovation of this study lies in the convective heat transfer strategy to detect changes in output voltage signals in the non-obstructive, albeit inflammatory and otherwise considered normal arterial regions."

Scientists have demonstrated that frictional force acting on the walls of vessels by blood flow, known as shear stress, is intimately involved in oxidative stress and inflammatory responses that lead to atherosclerosis. In athero-prone regions, the flow is disturbed, yet detection of changing flow patterns in real-time remains a challenge.

Dr. Hsiai's group developed a micro-electro-mechanical system (MEMS) by depositing titanium and platinum on a flexible polymer membrane and patterning them to form the sensing elements. They deployed the sensor via an angiogram catheter into the aortic and abdominal arteries of rabbits that had eaten a high fat, high cholesterol diet, and a control group that had eaten a normal diet.

An electric current passed through the sensing element and generated a thermal layer in the flow field, from which convective heat transfer was measured as a function of the voltage signals. In the regions of atherosclerotic lesions, blood flow is disturbed. This causes changes in convective heat transfer from the sensing element to the flow field, and thus, changes in voltage signals. The sensor measured a high voltage upstream from the part of the blood vessel that harbored the atherosclerotic plaque, and a low voltage downstream.

The scientists concluded that the MEMS thermal sensor method could sensitively detect pre-atherosclerotic regions that otherwise showed no clinical signs of atherosclerosis. The authors integrated mathematical simulations, fluoroscopic images, and dissection of the aortas to verify their results.

Once the MEMS thermal sensors have identified the atherosclerotic lesion, doctors can identify whether this lesion is a vulnerable or stable plaque. A vulnerable plaque could rupture, which blocks the arteries and causes heart attacks and strokes. Doctors perform angioplasty and implant stents to prevent blockage of vessels. However, lifestyle changes and medication can manage stable plaque. According to Dr. Hsiai, "Despite imaging modalities, we have yet to develop a means to differentiate vulnerable from stable plaque. If we can differentiate vulnerable from stable plaque during a diagnostic angiogram, we can avoid unnecessary complications from angioplasty and stenting, and deliver an enhanced risk-to-benefit profile for our patients. It could also reduce health costs by eliminating unnecessary procedures and for treating procedure-related complications."


Story Source:

The above story is based on materials provided by Springer Science+Business Media. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fei Yu, Lisong Ai, Wangde Dai, Nora Rozengurt, Hongyu Yu, Tzung K. Hsiai. MEMS Thermal Sensors to Detect Changes in Heat Transfer in the Pre-Atherosclerotic Regions of Fat-Fed New Zealand White Rabbits. Annals of Biomedical Engineering, 2011; DOI: 10.1007/s10439-011-0283-8

Cite This Page:

Springer Science+Business Media. "MEMS thermal sensor detects pre-atherosclerotic lesions." ScienceDaily. ScienceDaily, 7 March 2011. <www.sciencedaily.com/releases/2011/03/110307101448.htm>.
Springer Science+Business Media. (2011, March 7). MEMS thermal sensor detects pre-atherosclerotic lesions. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2011/03/110307101448.htm
Springer Science+Business Media. "MEMS thermal sensor detects pre-atherosclerotic lesions." ScienceDaily. www.sciencedaily.com/releases/2011/03/110307101448.htm (accessed July 29, 2014).

Share This




More Health & Medicine News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
$15B Deal on Vets' Health Care Reached

$15B Deal on Vets' Health Care Reached

AP (July 28, 2014) A bipartisan deal to improve veterans health care would authorize at least $15 billion in emergency spending to fix a veterans program scandalized by long patient wait times and falsified records. (July 28) Video provided by AP
Powered by NewsLook.com
Two Americans Contract Ebola in Liberia

Two Americans Contract Ebola in Liberia

Reuters - US Online Video (July 28, 2014) Two American aid workers in Liberia test positive for Ebola while working to combat the deadliest outbreak of the virus ever. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
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:
from the past week

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