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 New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia

nachricht New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>