As an undergraduate student in China, Hong Chen knew what she wanted to do with her life: she wanted to work on things that could have an impact on human health or patient care. She was told, however, that that goal was too big to achieve.
Chen did not let the discouragement stop her and found a way to reach her goal that would set her apart from others.
"I thought if I wanted to make an impact, ultrasound is the area I want to get into, because it is probably the most widely used imaging tool in medicine," says Chen, assistant professor of biomedical engineering in the School of Engineering & Applied Science and of radiation oncology in the School of Medicine. "After I got into the ultrasound field, I realized that ultrasound is not only used for imaging, but also for therapy. The more I get into the field, the more I realize this is the technique that is going to revolutionize medicine."
Ultrasound, an affordable imaging technique that uses sound waves to take images inside the body, has been in use for nearly 100 years and is commonly used in medicine today, from providing one's first photo while in the womb to helping physicians make diagnoses. Chen is working to use that proven technology to deliver drugs directly to where they are needed.
"The new application of ultrasound is in therapy — that's where amazing things happen," she says. "One technique, called image-guided focused ultrasound, is used to identify where the disease area is, perform the treatment using focused ultrasound and monitor the area to make sure the treatment is delivered safely at the right location."
Chen leads a working group of physicians, other researchers, postdoctoral researchers and graduate students in which she blends her expertise as a biomedical engineer developing new ultrasound and magnetic resonance (MR) image-guided techniques with clinical applications at the School of Medicine. The team already is using the techniques in clinical trials with healthy volunteers to determine its feasibility on humans.
The focused ultrasound can focus on a spot, such as a tumor, as small as a grain of rice, says Chen, who joined the Washington University faculty in July 2015 and became a member of the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine earlier this year.
"The concept is like using a magnifying glass in the sunlight – you can focus the light where you want it," she says. "With the focused ultrasound transducer, we can focus the soundwave through the skin deep into the body. It has the advantages of being a safe and noninvasive therapeutic technique with deep penetration through the body, even the skull."
The Radiation Oncology Department at the School of Medicine has installed an MR-guided high-intensity focused ultrasound system in the Center for Advanced Medicine.
"In the past, they would use a thermometer in the patient to measure temperature," she says. "Now, we don't have to do that because the MR thermometry can provide a 3-D image of the temperature instead of measurement at a single point, offering more precise treatment."
Chen and her team plan to build a portable ultrasound therapy system that can be taken to other researchers' labs to collaborate and to hospital operating rooms. A startup company to create the portable systems may also be in the works.
Chen's determination to reach her goals began at Xi'an Jiaotong University in Shaanxi, China, where she earned bachelor's and a master's degrees in biomedical engineering and the newest member of the university's McDonnell International Scholars Academy. Knowing she wanted to pursue a doctorate, she began contacting researchers worldwide about her interest in focused ultrasound. One of the researchers with whom she communicated was Larry Crum, principal physicist and research professor at the University of Washington. They met at a conference in Beijing, and Crum invited her to work in his lab. Her training there was heavy on the fundamentals and physics aspects of the field. She went to Columbia University in New York where she got preclinical research training through postdoctoral research with Elisa Konofagou, professor of biomedical engineering and radiology.
Chen was drawn to WashU because of its strong position in the imaging field in both the School of Engineering & Applied Science and the School of Medicine, with research ranging from the microscopic, such as the imaging of tissues and cells, to the macroscopic imaging of the whole body, and from basic research to clinical application.
"I believe WashU provides the best research environment I could ever hope for, because it gives me the opportunity to bridge the gap between engineering and medicine," she says. "On my team, there are already physicians, cancer biologists and other physicists."
Chen will share her knowledge of ultrasound imaging with undergraduate students this fall in what is the first course on the subject taught in the Department of Biomedical Engineering. Already, the course has generated a buzz among students, who also have flocked to work in her lab. She has "an army of undergraduates," a graduate student, a technician and a postdoctoral researcher working in her lab.
"I always tell my undergraduates that I have the best ones from each year," she says. "They can accomplish things that are beyond my expectations. I believe the undergraduates here at WashU are amazing."
Chen says she wants to give everyone interested in working in her lab the opportunity to work in it to gauge interest in research and because she wanted to work in a lab as an undergraduate but did not have the opportunity.
"I tell everyone in my group that the moment they join my group, they are a scientist," she says. "I don't care if you are an undergrad or a postdoc, you are a scientist."
Chen's mentor, Crum, was her role model on how to run a lab.
"What I learned from him is that if I want to be a great scientist, I have to be a great person," she says. "You have to not only have great scientific achievements, but be a great person who cares about your mentees and other people. Otherwise, your research won't go very far."
The School of Engineering & Applied Science at Washington University in St. Louis focuses intellectual efforts through a new convergence paradigm and builds on strengths, particularly as applied to medicine and health, energy and environment, entrepreneurship and security. With 90 tenured/tenure-track and 40 additional full-time faculty, 1,300 undergraduate students, more than 900 graduate students and more than 23,000 alumni, we are working to leverage our partnerships with academic and industry partners — across disciplines and across the world — to contribute to solving the greatest global challenges of the 21st century.