Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Seeking a mechanical solution to nation’s number-one children’s illness

26.02.2004


Biomedical engineers at Lehigh University and Children’s Hospital of Pittsburgh probe causes of eustachian tube dysfunction in hopes of finding new treatments for ear infections



It will come as no surprise to parents that the most common illness among small children in America today is the middle-ear infection.

Each year, Americans spend $5 billion on ear infections. Doctors often prescribe two different antibiotics for the same infection. For more serious cases, they perform 500,000-plus surgeries annually, by inserting a tube in the ear drum to alleviate pressure caused by infections.


Nonetheless, about 20 percent of children have repeated episodes of ear infections that persist into adolescence and even adulthood. Chronic infections can lead to loss of hearing and balance, as well as to more critical inner-ear infections.

Meanwhile, researchers scramble to develop new antibiotics as bacteria become resistant to existing drugs.

Samir Ghadiali, professor of mechanical engineering and mechanics at Lehigh University in Bethlehem, Pa., thinks there is a better way to tackle the problem.

Ghadiali, a member of Lehigh’s Bioengineering and Life Sciences Program, studies the biomechanical and biophysical properties that govern the eustachian tube, which connects the middle ear to the back of the nose and the upper throat and which helps to regulate air pressure inside the ear.

Ghadiali’s work is an example of the growing role played by engineers in the quest to find and test new remedies for medical problems.

Although eustachian tube dysfunction is the primary cause of middle-ear disease, he says, antibiotics and ear tubes do not seek to improve the tube’s function.

"The goal of our research is to identify the causes of eustachian tube dysfunction," says Ghadiali. "We hope this leads to the development of novel treatment therapies that target the underlying cause of middle-ear disease."

The eustachian tube is a complex system of muscle, cartilage, and fat tissue. In healthy adults, it opens and closes three or four times a day, and more frequently when an excursion into higher altitudes causes a change in air pressure and triggers the ears to pop. An infection causes the ears to pop more frequently, but a more serious affliction may prevent the eustachian tube from opening and closing altogether.

Ghadiali applies engineering principles, such as fluid dynamics and solid mechanics, and engineering tools, including finite element analysis and mathematical modeling, to simulate how the eustachian tube opens.

"If we can open the eustachian tube," he says, "this will help prevent bacteria from accumulating and inflammation from occurring in the middle ear. An infection may clear up regardless of the antibiotic. This will decrease the number of pills that doctors need to prescribe."

Ghadiali collaborates with doctors and medical researchers at Children’s Hospital of Pittsburgh (CHP), where he is a former research professor. At CHP, Ghadiali designed a testing apparatus to measure the mechanical properties of the eustachian tube. He also developed mathematical models to interpret and quantify those properties.

Mathematical models, says Ghadiali, allow researchers to study the eustachian system more efficiently and across a much wider range of situations than can be done by merely doing physical experiments in a laboratory. The models also enable researchers to change the parameters of their experiments in a more precise manner.

After researchers run a computer simulation on their model, says Ghadiali, they do a corresponding physical experiment in the lab to see how closely their results match. If a simulation faithfully reproduces the experiments, the model on which it is based can be used in other tests.

One goal of Ghadiali’s research is to answer a question that has long baffled doctors - why the eustachian tube opens and closes easily in some people and not in others.

Engineers, he says, can answer that question by modeling the functioning of a healthy eustachian tube and using the model to predict the physical behavior of a diseased tube.

"Up until recently, researchers have visualized the ear’s interior and speculated why the eustachian tube does or does not open," Ghadiali says. "We are attempting to push past this limitation by taking the same imaging data [from people who do not have ear infections] and creating mathematical models. By going from the image to the model, we can simulate whether or not the tube will open and we can quantify certain parameters, such as how long the tube will stay open."

Ghadiali also hopes to apply his models to each of the six or seven distinct "patient populations" identified by doctors as having eustachian tubes that, for differing reasons, resist opening. By learning why the tube does not open in a specific group, he says, researchers believe they can fashion a solution for that particular group.

Chronic ear infections are often a developmental phenomenon, Ghadiali says, because anatomy changes as a person ages. Ghadiali and his colleagues are examining children from a few months to 2 years old, those aged 2 to 6, those aged 7 to 12, and teenagers, as well as patients who have undergone cleft-palate surgeries, another group which is prone to chronic infections.

From a mechanical engineering standpoint, says Ghadiali, many physical parameters could cause ear infections. These include the elastic properties of tissues, the size of tissues, and the adhesion properties on the surface of the eustachian tubes.

"We don’t know which of these are crucial in the different patient populations," says Ghadiali. "Until we do, we’re operating in the dark. We can design therapies, such as tissue engineering to modify elasticity of tissues, but we don’t know which therapy to use."

Ghadiali is also investigating, at the molecular level, the mucus buildup that is triggered by the presence of certain proteins and that could play a role in ear infections.

"We are enhancing all of our mathematical models to account for these molecular-adhesion forces. This is a multi-scale fluid dynamics problem."

Ghadiali has a Ph.D. in biomedical engineering from Tulane University.

Kurt Pfitzer | EurekAlert!
Further information:
http://www.lehigh.edu/

More articles from Health and Medicine:

nachricht 'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers
16.02.2018 | National University of Science and Technology MISIS

nachricht New process allows tailor-made malaria research
16.02.2018 | Eberhard Karls Universität Tübingen

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

Im Focus: Autonomous 3D scanner supports individual manufacturing processes

Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).

Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Fingerprints of quantum entanglement

16.02.2018 | Information Technology

'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers

16.02.2018 | Health and Medicine

Hubble sees Neptune's mysterious shrinking storm

16.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>