Mechanical Engineering and Medicine Collide

By Charlie Chermak

Have you ever been curious how asthma medication travels throughout your body or how blood flow is affected by plaque buildup in your arteries? New research in the field of fluid mechanics is bringing fresh insights to these not-so-simple phenomena that occur within our bodies. On November 15, 2019 at the University of Wisconsin-Madison, Dr. Jenn Stroud Rossmann, Professor of Mechanical Engineering at Lafayette College, presented her latest research for the Mechanics Seminar Series in a presentation titled, “Modeling biological flows in diseased vessels.” In this presentation, Stroud Rossman, a fluid mechanician who studies the motion of liquids and gases, illustrated the potential of advanced engineering tools to empower doctors to more effectively diagnose and treat a variety of health problems.

The study of blood flow, or hemodynamics, brings together a variety of disciplines. Stroud Rossmann set the stage for her research findings by providing an introduction to the tools she uses in her research, which are rooted in fluid mechanics. They utilize a series of equations that govern the flow of fluids, or liquids and gases, which she affectionately described as “gorgeous.” Using advanced computing as the mathematical workhorse behind the scenes, her research is capable of accurately representing, or modeling, the flow of blood through models of diseased blood vessels that contain plaque, otherwise known as atherosclerosis or “hardening of the arteries.” This allows the specific biological mechanisms by which certain diseases occur to be more clearly understood, which is a critical component of diagnosis and treatment in the world of medicine.

Two examples from her presentation, blood flow through the carotid artery and the flow of asthma medicine within the airways, convey the unique insights her type of work can produce to better understand common yet complex biological processes.

The carotid arteries are the blood vessels that bring blood to your head and neck. They contain a unique fork in the road, or bifurcation, that is a common location for plaque buildup, or atherosclerosis. This can lead to dangerous blood flow blockage, or carotid stenosis. Due to limitations in imaging technology, it can be difficult for doctors to identify and diagnose this condition. Using relatable terms like “oozing toothpaste,” Stroud Rossman demonstrated how her research is helping to identify high-risk areas in these arteries where problems are likely to occur. Specifically, her research found that there are areas where periodic forces can actually break off chunks of calcified plaque. As a result of her research, doctors will be better equipped to identify unhealthy carotid bifurcations and consider treatment options for their patients.

Another example Stroud Rossman discussed applies her fluid mechanics toolkit to the study of asthma. Using these tools, her team accurately modeled the travel of inhaled asthma medicine throughout the lungs, a phenomenon more complicated than one might expect. The complexity stems from the interaction between the asthma medicine droplets and the lining of mucus within the airways. Despite the complexity of this biological phenomenon, her research was able to model the scenario effectively. She even provided health tips to any people with asthma in the audience, encouraging the use of a quiet, deep breath to facilitate the flow of the medicine droplets deep within the lungs.

Using a combination of clear, conversational language and robust academic methods, Stroud Rossman vividly conveyed the value of fluid mechanics research in medicine and the power it can provide for the diagnosis and treatment of disease.