Directing Light and Learning from Sound to Guide Surgeries

Muyinatu (Bisi) Bell, Johns Hopkins University

Just like programming a robot requires meticulous planning, coding, and execution, these same requirements are ever present when designing and controlling the individual optical and acoustic components of photoacoustic imaging systems. Photoacoustic imaging utilizes light and sound to make images by transmitting laser pulses that illuminate regions of interest, which subsequently absorb the light, causing thermal expansion and the generation of sound waves that are detected with conventional ultrasound transducers. The Photoacoustic and Ultrasonic Systems Engineering (PULSE) Lab is developing novel methods that use photoacoustic imaging to guide surgeries with the ultimate goal of eliminating surgical complications caused by injury to important structures – like major blood vessels and nerves – that are otherwise hidden from a surgeon’s immediate view.

In this talk, I will describe our novel light delivery systems that attach to surgical tools in order to direct light toward the surgical site. I will also introduce how we learn from the physics of sound propagation in tissue to develop acoustic beamforming algorithms that improve image quality, using both state-of-the-art deep learning methods and our newly developed spatial coherence theory. These light delivery and acoustic beamforming methods hold promise for robotic tracking tasks, visualization and visual servoing of surgical tool tips, and assessment of relative distances between the surgical tool and nearby critical structures (e.g., major blood vessels and nerves that if injured will cause severe complications, paralysis, or patient death). Impacted surgeries and procedures include neurosurgery, spinal fusion surgery, hysterectomies, and biopsies.

Speaker Biography

Muyinatu Bell is an Assistant Professor of Electrical and Computer Engineering with a joint appointment in the Biomedical Engineering Department at Johns Hopkins University, where she founded and directs the Photoacoustic and Ultrasonic Systems Engineering (PULSE) Lab. Dr. Bell earned a B.S. degree in Mechanical Engineering (biomedical engineering minor) from Massachusetts Institute of Technology (2006), received a Ph.D. degree in Biomedical Engineering from Duke University (2012), and conducted research abroad as a Whitaker International Fellow at the Institute of Cancer Research and Royal Marsden Hospital in the United Kingdom (2009-2010). Prior to joining the faculty, Dr. Bell completed a postdoctoral fellowship with the Engineering Research Center for Computer-Integrated Surgical Systems and Technology at Johns Hopkins University (2016), where she was co-mentored by faculty in the Computer Science Department and the School of Medicine. Dr. Bell has published over 40 scientific journal articles and conference papers, holds a patent for short-lag spatial coherence beamforming, and is the recipient of numerous awards, grants, and fellowships, including the NIH K99/R00 Pathway to Independence Award (2015), MIT Technology Review’s Innovator Under 35 Award (2016), and the NSF CAREER Award (2018).