Abstract

Photoacoustic imaging has gained widespread popularity in molecular and preclinical applications, yet it is often excluded from conversations among primary care physicians, surgeons, and interventional radiologists. As an imaging modality that relies on light transmission, optical absorption, and the subsequent generation of sound waves, three primary challenges hinder its clinical advancement: (1) acoustic clutter noise artifacts; (2) limited optical penetration depths; and (3) restrictive system designs that fix light sources relative to acoustic receivers.

In this talk, I propose the integration of optical, acoustic, and robotic principles to overcome existing challenges. Acoustic clutter, which plagues ultrasound and photoacoustic images alike, is mitigated with a novel short-lag spatial coherence (SLSC) beamformer that I developed, resulting in improved image quality and an effective tripling of optical penetration depths. It is advantageous over conventional methods when applied to longstanding and emerging clinical practices, including transcranial, prostate, and vascular photoacoustic imaging, as well as liver, fetal, and cardiac ultrasound imaging. I will describe the acoustic theories that enable these improvements and demonstrate feasibility with data from computer simulations, phantoms, ex vivo tissue, and in vivo animal and human studies.  Finally, I will show that autonomous or cooperative robotic control relies on this optimal image quality to enhance the maneuverability of system components, and thereby facilitate the flexible separation of light delivery from acoustic reception. This work promises to expand the technical envelope of photoacoustic imaging systems and revolutionize clinical standards of care.

Speaker Bio

Dr. Muyinatu A. Lediju Bell is a postdoctoral fellow at Johns Hopkins University. She received her Ph.D. in Biomedical Engineering from Duke University in 2012 and earned her B.S. in Mechanical Engineering with a minor in Biomedical Engineering from the Massachusetts Institute of Technology in 2006. Dr. Bell is a recipient of numerous awards and fellowships including a Whitaker International Fellowship to spend a year abroad conducting research in the United Kingdom (2009), the UNCF-Merck Graduate (2011) and Postdoctoral (2012) Research Fellowships, and the Ford Foundation Postdoctoral Fellowship for her commitment to using diversity as a resource for enriching the education of all students (2012). Her research interests include ultrasound and photoacoustic imaging, image-guided surgery, medical robotics, and medical device design.