New Technology Promises Compact High-Intensity Therapeutic Ultrasound

George Lewis with his newest portable ultrasound device.

George Lewis, Jr. is a 23 year old, third-year PhD candidate in Biomedical Engineering at Cornell University. During his first year of graduate study, George took part in an NIBIB-funded T35 summer clinical immersion program at Weill Cornell Medical College directed by Dr. Yi Wang, Professor of Radiology at Weill Cornell Medical College and Professor of Biomedical Engineering at Cornell University. During that time, George, like his biomedical engineering classmates, shadowed clinician mentors and participated in short-term research projects directly related to their mentors’ clinical practice. They also were directly exposed to the clinical environment, helping to acquaint them with clinical needs and the challenges of using biomedical technology in the clinical setting.

From discussions with clinical mentors in the Department of Nephrology and the William Randolph Hearst Burn Center at Weill Cornell Medical center, Lewis became interested in the possible uses of therapeutic ultrasound for tissue ablation and blood loss reduction during surgical operations. He also was made aware of the clinical importance of developing a portable ultrasound cauterization unit that could be used to facilitate non-suture wound closure and the occlusion of bleeding blood vessels. These discussions inspired him to examine the limitations of current ultrasound technology. Despite the growing interest in and development of many new therapeutic ultrasound applications, Lewis found that basic ultrasound transducer hardware had not changed much in the past 50 years. Moreover, most ultrasound transducers now in use, because of their relative inefficiency, required high power amplifiers to achieve the necessary acoustic output for therapeutic applications.

Lewis and Dr. William Olbricht, Professor of Chemical and Biomolecular Engineering at Cornell University, have recently created a novel design for an inexpensive, portable ultrasound device that is a significant improvement over existing devices. By developing an ultrasound transducer with almost double the efficiency of traditional transducers, Lewis and Dr. Olbricht were able to build a pocket-sized, battery-powered ultrasound device that is smaller, considerably more efficient, and many times less expensive than existing devices with similar function. This portable ultrasound device has the potential to replace “plug-in” systems used in medical research. The complete system cost $140 to build, and is capable of field service on its internal battery, making it especially useful for ambulatory, military, and telehealth medical applications. Lewis and Dr. Olbricht hope that their new ultrasound technology, now undergoing animal trials (see below), one day will be developed into practical portable clinical devices that emergency room doctors could use to stabilize a gunshot wound, military medics could carry to cauterize bleeding wounds, or dentists could use to enable the body to instantly absorb locally injected anesthetics.

Lewis’ current PhD research is focused on using therapeutic ultrasound to non-invasively ablate cancerous tissue and to enhance the delivery of chemotherapeutic drugs across the blood-brain barrier. His and Dr. Olbricht’s new ultrasound unit also is being tested in a clinical setting at Weill Cornell Medical College. Under the direction of Jason Spector, Director of Weill Cornell's Laboratory for Bioregenerative Medicine and Surgery and assistant professor of plastic surgery, Peter Henderson is using one of the devices in experiments that aim to minimize injury that occurs when tissues do not receive adequate blood flow. Their laboratory is performing tests in animals to determine whether low doses of hydrogen sulfide, known to be toxic at high doses, might be able to minimize such injury by slowing cellular metabolism.