Breaking Limits in Photoacoustic Imaging: Deeper, Faster, and More colorful

Junjie Yao, Ph.D.

Assistant Professor

Biomedical Engineering

Duke University

Seminar Information

Seminar Date
December 2, 2022 - 2:00 PM


Junjie Yao


By acoustically detecting the optical absorption contrast in biological tissues, photoacoustic imaging (PAI) has proven increasingly powerful for multi-scale anatomical, functional, and molecular imaging. In PAI, a short-pulsed laser beam illuminates the biological tissue to generate a small but rapid temperature rise, which leads to emission of ultrasonic waves due to thermoelastic expansion. The wideband ultrasonic waves are detected to form a high-resolution tomographic image that maps the original optical absorption in the tissue. My talk will focus on several major new fronts of PAI that have collectively enabled fast, deep, and high-sensitivity biomedical applications in functional neuronal imaging, drug testing, early cancer detection, and interventional therapy. First, PAI has broken the penetration limit and achieved super-deep (~10 cm) imaging by using advanced internal light delivery, extending its applications ready into internal organ imaging on large animal models. Second, by innovating novel scanning technologies, PAI has been accelerated by more than 1000 times in imaging speed with a large field of view and high spatial resolution, allowing for the monitoring of highly dynamic biological processes, particularly for brain activities. Third, by adapting novel fabrication technologies in optics and acoustics, miniaturized PAI has achieved handheld, wearable and head-mounted imaging with high spatial–temporal resolutions and high throughput. Lastly, taking advantage of switchable or tunable near-infrared photoacoustic-specific probes, PAI has improved its sensitivity and specificity by more than 1000 times, enabling highly sensitive detection of malignant cancer, tissue hypoxia, and neuronal activities.

Speaker Bio

Dr. Junjie Yao is currently Assistant Professor of Biomedical Engineering at Duke University, and a faculty member of Duke Center for In Vivo Microscopy, Duke Cancer Institute, Duke Institute of Brain Sciences, and Fitzpatrick Institute for Photonics. 

Dr. Yao received his B.S. (2006) and M.S. (2008) degrees in Biomedical Engineering from Tsinghua University (Beijing, China), and his Ph.D. degree in Biomedical Engineering at Washington University in St. Louis in 2013 under the mentoring of Dr. Lihong V. Wang. Dr. Yao is the receipt of the 2019 IEEE Photonic Society Young Investigator Award, 2021 National Jewish Fund Faculty Fellowship, and 2022 NSF CAREER Award. 

Combining light and sound, Dr. Yao’s research interest is in developing photoacoustic tomography (PAT) technologies in life sciences, especially in high-speed functional brain imaging, deep-tissue molecular imaging, and early-stage cancer detection. Dr. Yao has received research funds from various agencies including NIH, NSF, AHA, and CZI. More information about Dr. Yao’s research at